U.S. patent application number 10/523151 was filed with the patent office on 2005-11-03 for method for production of peptides/amino acids produced by said method and use of the same.
This patent application is currently assigned to Aminotech AS. Invention is credited to Carlsson, Tomas.
Application Number | 20050244567 10/523151 |
Document ID | / |
Family ID | 31982173 |
Filed Date | 2005-11-03 |
United States Patent
Application |
20050244567 |
Kind Code |
A1 |
Carlsson, Tomas |
November 3, 2005 |
Method for production of peptides/amino acids produced by said
method and use of the same
Abstract
According to a first aspect there is a method for producing a
protein-free product comprising free amino acids and short
peptides, wherein raw protein materials are crushed and hydrolysed
with endogenous enzymes and passed through different separation
processes, including coagulation of protein residues, in order to
obtain the desired product. The invention further comprises the
product obtained and uses thereof. According to a second aspect, a
protein product enriched with free amino acids and short peptides
is produced, wherein the raw protein materials are ground and
hydrolysed with endogenous enzymes, and wherein the hydrolysate
undergoes various separation processes. The product obtained
comprises proteins, short and long peptides, free amino acids and
minerals and has a low fat content and salt content. According to a
third aspect, hydrolysation of a protein-containing raw material
and separation of amino acids/peptides is carried out, wherein the
hydrolysation is effected by using the endogenous enzymes of the
protein-containing raw material. The hydrolysate is passed through
a membrane filter, wherein peptide/amino acids follow a permeate
stream, whilst the active enzymes continuously break down any
protein residues that are deposited on the membrane surface. The
enzymes are passed together with retenate back to the hydrolysis.
Furthermore, an amino acid and peptide product and an oil product
are described and the use thereof is disclosed.
Inventors: |
Carlsson, Tomas; (Lesja,
NO) |
Correspondence
Address: |
VOLPE AND KOENIG, P.C.
UNITED PLAZA, SUITE 1600
30 SOUTH 17TH STREET
PHILADELPHIA
PA
19103
US
|
Assignee: |
Aminotech AS
Lesja
NO
|
Family ID: |
31982173 |
Appl. No.: |
10/523151 |
Filed: |
January 27, 2005 |
PCT Filed: |
July 29, 2003 |
PCT NO: |
PCT/NO03/00260 |
Current U.S.
Class: |
426/656 |
Current CPC
Class: |
A23V 2002/00 20130101;
B01D 61/002 20130101; A23J 1/04 20130101; C11B 1/10 20130101; A23V
2002/00 20130101; C12P 21/06 20130101; C01B 25/32 20130101; B01D
2315/10 20130101; B01D 61/022 20130101; A23J 3/341 20130101; A23K
20/147 20160501; C11B 3/003 20130101; A61K 38/01 20130101; A23V
2300/34 20130101 |
Class at
Publication: |
426/656 |
International
Class: |
A23J 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 29, 2002 |
NO |
20023601 |
Jul 29, 2002 |
NO |
20023602 |
Jul 29, 2002 |
NO |
20023603 |
Claims
1. A method for recovering peptides/amino acids and oil/fat from
one or more protein-containing raw materials wherein the method
comprises the following steps: a. grinding the raw materials; b.
heating the ground raw materials to a temperature in the range of
40-62.degree. C., preferably 45-58.degree. C.; c. optionally before
and/or after the heating step, separating oil/fat from the raw
materials in order to obtain a first oil product; d. adding water,
the water having approximately the same or the same temperature as
the raw materials, and wherein the pH of the water is adjusted by
adding calcium; e. hydrolysing the raw materials with endogenous
enzymes in order to prepare a hydrolysate: f. optionally during the
hydrolysation step, adding a pH adjuster in order to maintain the
desired pH value of the hydrolysate; g. heating the hydrolysate to
75-100.degree. C., preferably 85-95.degree. C.; h. removing large
particles from the hydrolysate, including non-hydrolysed proteins,
which can be returned to the hydrolysis; i. optionally separating
off fat/oil in order to obtain a second oil product; j. coagulating
the proteins; k. removing the coagulated proteins; l. optionally
separating off fat/oil in order to obtain a third oil product; m.
optionally concentrating the remaining amino acids and short
peptides; and n. optionally drying the concentrate in order to
obtain dry short peptides and amino acids.
2. The method according to claim 1, wherein the water added in step
d comprises 10-40%, preferably 20-30% water of a total reaction
mixture.
3. The method according to claim 1, wherein the method takes place
as a closed process.
4. The method according to claim 1, wherein the pH adjuster in step
f is nitrogen gas, calcium or bone meal.
5. The method according to claim 1, wherein the method further
comprises dividing the large particles from step h into bone
portions for producing hydroxy apatite, protein residues that can
be returned to the hydrolysis, and other solid particles.
6. The method according to claim 1, wherein the peptide and amino
acid product has a fat content of <0.1% and a salt content of
<1%.
7. The use the method according to claim 1 for producing a
pharmaceutical product.
8. The use the method according to claim 1 for producing a food
product.
9. The use the method according to claim 1 for producing a feed
product.
10. The use the method according to claim 1 for producing a
biotechnological product.
11. The use the method according to claim 1 for producing hydroxy
apatite.
12. Amino acids/peptides prepared by the method of claim 1, wherein
the amino acids/peptides do not contain allergens and DNA traces,
and that the fat content is <0.1% and the amino acids/peptides
have a salt content of <0.5% by weight.
13. Hydroxy apatite produced by the method of claim 5, wherein the
hydroxy apatite does not contain allergens and DNA traces.
14. The first oil product produced by the method of claim 1, is
cold-pressed and is of foodstuff quality.
15. A method for recovering peptides/amino acids from one or more
protein-containing raw products, wherein the method comprises the
following steps: a. grinding the raw materials; b. heating the
ground raw materials to temperatures in the range of 40 to
62.degree. C., preferably 45 to 58.degree. C.; c. optionally before
and/or after the heating step, separating oil/fat from the raw
materials in order to obtain a first oil product; d. adding water,
the water having approximately the same or the same temperature as
the raw materials, and wherein the pH of the water is adjusted by
adding calcium; e. hydrolysing the raw materials with endogenous
enzymes in order to prepare a hydrolysate; f. optionally during the
hydrolysation step, adding a pH adjuster in order to maintain the
desired pH value of the hydrolysate; g. heating the hydrolysate to
75-100.degree. C., preferably 85-95.degree. C.; h. removing large
particles from the hydrolysate including non-hydrolysed proteins;
i. optionally separating off fat/oil in order to obtain a second
oil product; j. removing the proteins and long peptides; k.
concentrating the remaining amino acids and peptides; l. returning
proteins and long peptides to the concentrate in order to obtain a
protein product; and m. optionally drying the protein product in
order to obtain a dried product containing proteins, free amino
acids and short and long peptides.
16. The method according to claim 15, wherein the water added in
step d comprises 10-40%, preferably 20-30% water of a total
reaction mixture.
17. The method according to claim 15, wherein the method takes
place as a closed process.
18. The method according to claim 15, wherein the pH adjuster in
step f is nitrogen gas, calcium or bone meal.
19. The method according to claim 15, wherein the method further
comprises dividing the large particles from step h into bone
portions for producing hydroxy apatite, protein residues and other
solid particles.
20. The method according to claim 15, wherein the protein product
comprises 5-95% by weight of free amino acids, preferably 30-60% by
weight.
21. The method according to claim 15, wherein the protein product
contains less than 0.5% by weight of fat.
22. The method according to claim 15, wherein the protein product
contains less than 1% by weight of salt.
23. The use of the method according to claim 15 for producing a
veterinary medical product.
24. The use of the method according to claim 15 for producing a
food product.
25. The use of the method according to claim 15 for producing a
feed product.
26. The first oil product produced by the method of claim 15,
wherein the oil is cold-pressed and is of foodstuff quality.
27. A method for recovering peptides/amino acids and oil/fat from a
protein-containing raw material, wherein the method comprises the
following steps: a. grinding the raw materials; b. heating the
ground raw materials to temperatures in the range of 40-62.degree.
C., preferably 45-58.degree. C.; c. optionally before and/or after
the heating step, separating oil/fat from the raw materials in
order to obtain a first oil product; d. adding water which has
approximately the same or the same temperature as the raw
materials, and wherein the pH of the water is adjusted by adding
calcium; e. hydrolysing the raw materials with endogenous enzymes
in order to prepare a hydrolysate; f. optionally during the
hydrolysation step, adding a pH adjuster in order to maintain the
desired pH value of the hydrolysate; g. removing solid particles
and non-hydrolysed proteins which can be returned to the hydrolysis
from the hydrolysate; h. periodically or continually separating off
fat/oil in order to obtain a second oil product; i. optionally
treating the hydrolysate against microorganism growth, preferably
with UV treatment; j. separating off the molecular weight fraction
of peptides/amino acids desired by membrane filtration, preferably
of crossflow type; k. routing the portions of the hydrolysate that
do not penetrate the membrane filter in point j back to the
hydrolysis in step e; l. concentrating and optionally drying the
permeate in order to obtain peptides/amino acids; and m. wholly or
partly returning the distillate from the concentration to the
permeate side of the membrane filter.
28. The method according to claim 27, wherein the method takes
place as a closed process.
29. The method according to claim 27, wherein the pH adjuster in
step f is nitrogen gas or bone meal.
30. The method according to claim 27, wherein the method further
comprises dividing the solid particles from step g into hydroxy
apatite, protein residues and other solid particles.
31. The method according to claim 27, wherein the second oil
product recovered in step h is passed through a filter, and any
heavy portions (e.g., stearic acid) are removed in order to obtain
a cold-pressed, protein-free sterile oil.
32. A method for the hydrolysation of one or more
protein-containing raw materials and the separation of amino
acids/peptide, characterised in that the hydrolysation is carried
out using the endogenous enzymes of the protein-containing material
or materials; and that the hydrolysate is passed through a
membrane-like filter, wherein peptides/amino acids follow a
permeate stream, whilst the active enzymes continuously break down
any protein residues that are deposited on the membrane surface and
the enzymes are passed together with the retenate back to the
hydrolysis.
33. A method for removing peptides and amino acids from a
hydrolysis mixture, characterised in that the hydrolysis mixture
comprising active enzymes, amino acids, peptides and non-converted
proteins is passed through a membrane filter, wherein amino acids
and any peptides are filtered off and the active enzymes present
act to break down proteins that are deposited on the membrane
filter.
34. The use of the method according to claim 27 for producing a
pharmaceutical product.
35. The use of the method according to claim 27 for producing a
biotechnological product.
36. The use of the method according to claim 27 for producing a
food product.
37. The use of the method according to claim 27 for producing a
feed product.
38. The use of the method according to claim 30 for producing
hydroxy apatite.
39. Amino acids/peptides produced by the method according to claim
27, wherein the amino acids/peptides do not contain allergens and
DNA traces, are virtually fat-free and have a salt content of
<0.5% by weight.
40. The oil produced by the method according to claim 31, wherein
the oil does not contain allergens or DNA traces.
41. The hydroxy apatite produced by the method according to claim
30, wherein the hydroxy apatite does not contain allergens or DNA
traces.
Description
FIELD OF INVENTION
[0001] The present invention relates to aspects concerning:
[0002] a) a method for producing a protein-free product containing
peptides, free amino acids and minerals from raw animal or aquatic
materials, and the products and their use as animal feed and/or in
products for the biotechnological, pharmaceutical and food
processing industries. An oil product that is a result of the
aforementioned method is also described.
[0003] b) a method for producing a protein product enriched with
free amino acids and short peptides, the product obtained and its
use as animal feed and/or in products for veterinary medical use
and in the food processing industry. An oil product that is the
result of the aforementioned method is also described.
[0004] c) a method for recovering peptides, free amino acids and
minerals from raw animal or aquatic materials.
[0005] In the industry it is known to produce peptides and amino
acids by acid hydrolysis, and using biotechnological and/or
chemical/technical, both natural and synthesised, concentrated
enzymes. The present invention is a way of using the naturally
occurring decomposing enzymes from raw animal or aquatic materials
in an industrial process that yields a product of pharmaceutical
quality, biotechnological quality, foodstuff quality or veterinary
medical quality.
[0006] By the term "pharmaceutical quality" is meant products for
intravenous use and products that are classified as medicine for
humans and animals or natural medicine.
[0007] By the term "biotechnological quality" is meant products
that can be used, for example, as culture media or catalysts in the
culturing of cells, bacteria, fungi and algae.
[0008] By the term "foodstuff quality" is meant products that are
used for human consumption either as an additive or as an
independent product.
[0009] By the term "veterinary medical quality" is meant products
that are classified as medicine for animals.
[0010] The invention may optionally also be used to produce feed
products in the form of an additive or as independent products.
BACKGROUND
[0011] Amino acids and peptides are well known in the
pharmaceutical, natural medicine and veterinary medical industries
as constituents of products such as intravenous foods and as
special foods for relieving certain trauma. To date, it is chiefly
extracts from blood plasma and protein hydrolysate produced using
pancreatic enzymes from pigs and calves that have been used in this
area. The invention provides the pharmaceutical industry with the
possibility of obtaining a supply of amino acids and peptides of a
hitherto unknown quality.
[0012] Amino acids and ultrashort peptides are also used for
biotechnological processes, for example, when a highly potent
culture medium is to be produced. A limitation for all industry
that cultivates single cell organisms or cell substrates from
higher organisms is the supply of culture media of adequate
quality. Defects or a high price are limiting factors. Moreover,
amino acids or peptides produced by biotechnological methods
generally contain growth-inhibiting substances which can be avoided
by using the products produced by the method of the invention. The
combination of spectra of natural amino acids and biological
micronutrients/minerals produced by the process described yields a
unique product for the preparation of culture media for the
biotechnological industry. Moreover, the technique can recycle
proteins from many types of cultures back to amino acids and
peptides which can then be reused.
[0013] Peptides/amino acids are used in the food processing
industry as binders, emulsifiers, flavouring additives and the
like. The uses are considerable and are increasing. The most used
peptides and amino acids in the food processing industry derive
from soya beans and milk. Amino acids and peptides from soya and
milk in particular are known for causing allergenic reactions which
can only be avoided by using another peptide/amino acid composition
which does not derive from these sources, or a peptide/amino acid
composition from soya or milk that has been sufficiently modified
so as not to cause these reactions. Therefore, there is a great
need for a method which provides a composition of amino acids and
peptides that can also derive from soya and/or milk, but which do
not cause allergenic reactions. Products from most animal sources
have not attained the same degree of utilisation as there are no
extraction techniques that maintain the functionality of the
product whilst removing undesired quality-reducing components such
as salt and fat.
[0014] Many different compositions of proteins, peptides and amino
acids deriving from different sources are used in the production of
animal feed. The composition of the peptides, the amino acids and
the proteins is also very important in the production of feed as
the animals' growth potential is dependent upon a balanced feed
intake. Therefore, in this area too, there is a great need for a
method which produces any desired composition that provides optimal
growth conditions for the animals.
[0015] In the following the term "endogenous" enzymes is used as a
term for the enzymes originating within the protein product as
opposed to the "exogenous" enzymes which are extraneous enzymes
added to the raw protein material during traditional hydrolysis.
One example of an "exogenous" enzyme is "Deterzyme APY", which is a
bacterial protease (E.C. 3.4.21) prepared by controlled
fermentation of Bacillus alcalophilus, and which can be purchased
from a number of suppliers. The term "endogenous" enzymes is also
used to mean enzymes extracted from other similar natural enzyme
materials or raw materials, preferably from cold-blooded
animals.
[0016] The term "hydrolysate" is used in the text below as a
designation for the raw materials that are being processed, i.e.,
that the warmed and pH-adjusted mixture of raw material and water
constitutes the hydrolysate. This applies in particular to aspects
a) and b) of the invention.
[0017] There are a number of patents in the field of the invention,
as for example RU 2103360 which describes a nutrient medium for
culturing eucaryotic cells and a method for preparing a hydrolysate
from fish internals which is prepared by proteolytic hydrolysis.
This hydrolysis process is carried out at a high pH adjusted with
sodium hydroxide, by using temperature inactivation, filtering and
drying in which the fish offal is mixed with distilled water in a
ratio of 1:1. The hydrolysis is carried out at a temperature of
+40.degree.-+42.degree. C. until a weight percentage of amino
nitrogen of 5.5-6-5% and a weight percentage of free amino acids of
50-60% are obtained.
[0018] SU 1755417 also discloses a method for the production of
hydrolysates from raw fish material in a fermenter to which a
fermentation preparation is added, followed by a filtering and
drying of the hydrolysate produced, wherein non-crushed raw
material is used that is fed periodically into the fermenter.
[0019] RU 1559466 describes a method for the production of
hydrolysates, which requires the crushing of fish products or scrap
from the processing thereof, mixing with water, heating the
mixture, adding a proteolytic fermentation preparation, fermenting,
filtering and drying, wherein raw materials and water are mixed in
a ratio of 2:1-1:1, and heated to a temperature of
+40.degree.-+45.degree. C., whilst fermentation is carried out over
a period of 0.5-2.5 hours using the exogenous enzyme protosubtilin
G3x.
[0020] Reference is also made to FR 2168259 which describes an
enzymatic hydrolysis of fish proteins that is carried out by
crushing fresh fish into a fine paste without adding water.
Exogenous enzymes are added and the paste is hydrolysed for about
15 hours depending upon desired solubility. The product is
stabilised for 5-20 minutes at +90.degree.-+100.degree. C., and is
filtered, pasteurised and centrifuged. The process yields products
of a high nutritional value.
[0021] As shown in the above, different techniques are known for
releasing proteins, peptides and amino acids from fish which are
suitable for food production. Moreover, it is also known to prepare
oil/fat from raw materials from both plant and animal sources.
SUMMARY
[0022] According to aspect a), the object of the present invention
is to provide a method for producing a protein-fee protein
hydrolysate based on the use of natural enzymes without the
addition of any non-natural substances. This is in contrast to
other methods which use enzymes from many different sources, such
as from bacterial cultures or the like.
[0023] It is also an object that the process should provide a
product that is completely free of protein and DNA and other
allergenic substances and that this is done without adversely
affecting the utilisation of the raw materials. The method is also
intended to reduce the fat in the end product to such a low level
that the disadvantages of using raw fish materials are eliminated.
It is intended to produce a product that can be used in many
different areas where the use of products produced by known methods
has been limited or made impossible because of their fat
content.
[0024] It is also an object to utilise the raw materials to the
full and to ensure that the environmental stresses associated with
the production are minimal.
[0025] Thus, according to aspect a) of the invention there is
provided a method for recovering peptides/amino acids and oil/fat
from protein-containing raw materials characterised in that it
comprises the following steps:
[0026] a. grinding the raw materials;
[0027] b. heating the ground raw materials to a temperature in the
range of 40-62.degree. C., preferably 45-58.degree. C.;
[0028] c. optionally before and/or after the heating step,
separating oil/fat from the raw materials in order to obtain a
first oil product;
[0029] d. adding water, the water having approximately the same or
the same temperature as the raw materials, and wherein the pH of
the water is adjusted by adding calcium;
[0030] e. hydrolysing the raw materials with endogenous enzymes in
order to prepare a hydrolysate:
[0031] f. optionally during the hydrolysation step, adding a pH
adjuster in order to maintain the desired pH value of the
hydrolysate;
[0032] g. heating the hydrolysate to 75-100.degree. C., preferably
85-95.degree. C.;
[0033] h. removing large particles from the hydrolysate, including
non-hydrolysed proteins, which can be returned to the hydrolysation
step;
[0034] i. optionally separating off fat/oil in order to obtain a
second oil product;
[0035] j. coagulating the proteins;
[0036] k. removing the coagulated proteins;
[0037] l. optionally separating off fat/oil in order to obtain a
third oil product;
[0038] m. optionally concentrating the remaining amino acids and
short peptides; and
[0039] n. optionally drying the concentrate in order to obtain dry
short peptides and amino acids.
[0040] Preferred embodiments of the method according to aspect a)
of the invention are set forth in subsidiary claims 2-6.
[0041] The method according to the invention facilitates the
production of a peptide and amino acid product having a low fat
content, preferably less than 0.1%. Furthermore, the produced
product contains natural minerals of biological origin. The salt
content of the product is less than 1%.
[0042] The invention also comprises a use of one of the methods
according to the invention for producing a biotechnological
product, a pharmaceutical product, a food product, and a feed
product, as disclosed in respective claims 7-10.
[0043] The invention also comprises the use of the method according
to the invention for producing hydroxy apatite as disclosed in
claim 11.
[0044] The invention also makes possible the production of amino
acids/peptides prepared by the method according to the invention,
and characterised as disclosed in claim 12.
[0045] There is also provided hydroxy apatite produced by the
method according to the invention and characterised in that it does
not contain any allergens and DNA traces, as disclosed in claim
13.
[0046] In addition, there is also provided an oil produced by the
method according to the invention and characterised in that it does
not contain allergens and DNA traces as disclosed in claim 14.
[0047] On the one hand, the present invention solves the problem of
producing products with a broad quality spectrum which varies from
their use for food products to their use in products that are to
meet the requirements for pharmaceuticals and the like, for
instance.
[0048] On the other hand, the present invention solves this problem
by using the endogenous enzymes of the raw materials and adapting
the production conditions to these enzymes.
[0049] The process differs essentially from the prior art
hydrolysis processes in that it may be carried out or is carried
out:
[0050] without any additives, such as chloroform, in order to
prevent unwanted bacterial growth;
[0051] without the addition of sodium hydroxide;
[0052] with the possibility of hot and cold recovery of
oil/fat;
[0053] with the possibility of controlling the spectrum of free
amino acids and peptides in the end product in selecting raw
materials for the process by choosing specific raw materials;
[0054] with the possibility of controlling the result of the
process, as regards the amino acid and peptide composition by means
of the applied process parameters such as temperature and pH;
[0055] without the addition of acid during the hydrolysation
process;
[0056] with a flexible combination of different raw materials;
[0057] by using an adapted concentration step for separating off
the product fractions; and in that
[0058] by removing proteins and large peptides that are not fully
hydrolysed through coagulation;
[0059] by filtering and separating off the coagulated proteins,
[0060] through the use of an adapted concentration technique,
and
[0061] by using a shorter time for hydrolysis,
[0062] it yields a product containing minerals and micronutrients
of biological origin.
[0063] According to aspect b), the object of the present invention
is to provide a method for producing a protein product containing
free amino acids and short and long peptides based on the use of
natural enzymes without the addition of any non-natural substances.
This is in contrast to other methods which use enzymes from many
different sources, such as from bacterial cultures and the
like.
[0064] Furthermore, the method is also intended to reduce the fat
in the end product to such a low level that the disadvantages of
using raw fish materials are eliminated. It is intended to provide
a product that is capable of use in many different areas where the
use of products produced by known methods has been limited or made
impossible because of their fat content.
[0065] Furthermore, it is an object to utilise the raw materials to
the full and to ensure that the environmental stresses associated
with the production are minimal.
[0066] Thus, as disclosed in claim 15, there is provided a method
for recovering a protein product containing peptides and free amino
acids from one or more protein-containing raw products,
characterised in that it comprises the following steps:
[0067] a. grinding the raw materials;
[0068] b. heating the ground raw material to temperatures in the
range of 40-62.degree. C., preferably 45-58.degree. C.;
[0069] c. optionally before and/or after the heating step,
separating oil/fat from the raw materials in order to obtain a
first oil product;
[0070] d. adding water, the water having approximately the same or
the same temperature as the raw materials, and wherein the pH value
of the water is adjusted by adding calcium;
[0071] e. hydrolysing the raw materials with endogenous enzymes in
order to prepare a hydrolysate;
[0072] f. optionally during the hydrolysation step, adding a pH
adjuster, for example, calcium, nitrogen or bone meal, in order to
maintain the desired pH value of the hydrolysate. A caustic
solution is not used for pH adjustment;
[0073] g. heating the hydrolysate to 75-100.degree. C., preferably
85-95.degree. C.;
[0074] h. removing large particles from the hydrolysate including
non-hydrolysed proteins;
[0075] i. optionally separating off fat/oil in order to obtain a
second oil product;
[0076] j. removing the proteins and long peptides;
[0077] k. concentrating the remaining amino acids and peptides;
[0078] l. returning proteins and long peptides to the concentrate
in order to obtain a protein product; and
[0079] m. optionally drying the protein product in order to obtain
a dried product containing proteins, free amino acids and short and
long peptides;
[0080] Preferred embodiments of the method according to aspect b)
of the invention are set forth in attached sub-claims 16-22.
[0081] The protein product produced by the method of the invention
is characterised in that it contains 5-95% by weight of free amino
acids, preferably 30-60% by weight, whilst the remaining 95-5%
comprises proteins and minerals, the minerals being natural
minerals of biological origin.
[0082] Furthermore, the protein product has a fat content of less
than 0.5% by weight and a low salt content, typically less than 1%
by weight.
[0083] The invention also comprises a use of the method according
to the invention for producing a veterinary medical product, a food
product and a feed product, as disclosed in respective claims 23,
24 and 25.
[0084] There is also provided an oil, characterised in that it is
the first oil product produced by the method according to the
invention and is of a foodstuff quality, as disclosed in claim
26.
[0085] On the one hand, the present invention according to aspect
b), among others, solves the problem of providing products having a
broad quality spectrum which varies from their use for food
production to the use of the products of pharmaceutical
quality.
[0086] On the other hand, according to aspect b), the present
invention solves this problem by using the endogenous enzymes of
the fish and adapting the production conditions to these
enzymes.
[0087] The process differs essentially from previously known
hydrolysis processes in that it may be carried out/is carried
out:
[0088] without additives, such as chloroform, in order to prevent
undesirable bacterial growth;
[0089] without the addition of sodium hydroxide;
[0090] with the possibility of hot and cold recovery of
oil/fat;
[0091] with the possibility of controlling the spectrum of free
amino acids and peptides in the end product in selecting raw
materials for the process by choosing specific raw materials;
[0092] with the possibility of controlling the result of the
process, as regards amino acid and peptide composition, by means of
the applied process parameters such as temperature and pH;
[0093] without the addition of acid during the hydrolysis;
[0094] with a flexible combination of different raw materials;
[0095] by using an adapted concentration step for separating off
product fractions; and in that
[0096] through the use of adapted concentration technique; and
[0097] by using a shorter time for hydrolysis; it yields a product
that contains minerals and micronutrients of biological origin.
[0098] The methods according to aspects a) and b) that are
described are a natural hydrolysis of proteins with the purpose of
obtaining dried end products having different compositions of short
peptides and free amino acids. The process yields finished products
that contain from 5% to 100% free amino acids, optionally without
proteins and long peptides (aspect (a)). In addition, the methods
describe the recovery of oils/fat.
[0099] According to aspect c) of the present invention, the object
is to provide a method for producing a protein hydrolysate based on
the use of natural enzymes without the addition of any non-natural
substances. This is in contrast to other methods that use enzymes
from many different sources such as bacterial cultures and the
like.
[0100] Furthermore, it is an object that the process according to
aspect c) should provide a product that is completely free of
protein and DNA and other allergenic substances, and that this is
done without adversely affecting the utilisation of the raw
materials. The method is also intended to reduce the fat in the end
product to such a low level that the disadvantages of using raw
fish materials are eliminated. It is intended to produce a product
that can be used in many different areas where the use of products
produced by known methods has been limited or made impossible
because of their fat content.
[0101] It is also an object to utilise the raw materials to the
full and ensure that the environmental stresses associated with the
production are minimal.
[0102] Thus, according to aspect c) of the invention there is
provided a method, as disclosed in claim 27, for recovering
peptides/amino acids and oil/fat from a protein-containing raw
material, characterised in that it comprises the following
steps:
[0103] a. grinding the raw materials;
[0104] b. heating the ground raw materials to temperatures in the
range of 40-62.degree. C., preferably 45-58.degree. C.;
[0105] c. optionally before and/or after separating oil/fat from
the raw material in order to obtain a first oil product;
[0106] d. adding water which has approximately the same or the same
temperature as the raw material, and wherein the pH of the water is
adjusted by adding calcium;
[0107] e. hydrolysing the raw materials with endogenous enzymes or
enzymes from similar raw materials, preferably from cold-blooded
species, in order to prepare a hydrolysate;
[0108] f. optionally during the hydrolysation step adding a pH
adjuster in order to maintain the desired pH value of the
hydrolysate;
[0109] g. removing solid particles and non-hydrolysed proteins
which can be returned to the hydrolysis from the hydrolysate;
[0110] h. periodically or continually separating off fat/oil in
order to obtain a second oil product;
[0111] i. optionally treating the hydrolysate against microorganism
growth, preferably with UV treatment;
[0112] j. separating off the molecular weight fraction of
peptides/amino acids desired by membrane filtration, preferably of
crossflow type;
[0113] k. routing the portions of the hydrolysate that do not
penetrate the membrane filter in point j back to the hydrolysis in
step e;
[0114] l. concentrating and optionally drying the permeate in order
to obtain peptides/amino acids;
[0115] m. wholly or partly returning the distillate from the
concentration step to the permeate side of the membrane filter.
[0116] Preferred embodiments of the method according to the
invention are set forth in attached sub-claims 28-31.
[0117] The term "membrane filter" is used in this context to mean
membrane-like filters such membrane filters, osmotic filters,
ultrafilters, electrostatic filters, crossflow filters and the
like. These should preferably be characterised by a cut-off value
of less than or equal to 10,000 daltons.
[0118] Moreover, there is provided a method, as disclosed in claim
32, for the hydrolysation of one or more protein-containing raw
materials and the separation of amino acids/peptides, which is
characterised in that the hydrolysation is carried out using the
endogenous enzymes of the protein-containing raw material or
materials and that the hydrolysate is passed through a membrane
filter, wherein peptides/amino acids follow a permeate stream,
whilst the active enzymes continuously break down any protein
residues that are deposited on the membrane surface and that the
enzymes are passed together with the retenate back to the
hydrolysis.
[0119] Another feature of the invention is a method, as disclosed
in claim 33, for separating peptides and amino acids from a
hydrolysis mixture, which is characterised in that the hydrolysis
mixture comprising active enzymes, amino acids, peptides and
non-converted proteins is passed through a membrane filter, wherein
amino acids and any peptides are filtered off and the active
enzymes present ensure that proteins deposited on the membrane
filter are broken down.
[0120] The invention also comprises a use of one of the methods
according to the invention for producing a pharmaceutical product,
a biotechnological product, a food product and a feed product, as
disclosed in respective claims 34-37.
[0121] The invention also comprises the use of the method according
to the invention for producing hydroxy apatite, as disclosed in
claim 38.
[0122] Furthermore, there are provided amino acids/peptides
produced by the method according to the invention and characterised
in that they do not contain allergens and DNA traces, as disclosed
in claim 39.
[0123] There is also provided an oil produced by the method
according to the invention and characterised in that it does not
contain allergens and DNA traces, as disclosed in claim 40.
[0124] Lastly, there is provided hydroxy apatite produced by the
method according to the invention and characterised in that it does
not contain allergens and DNA traces, as disclosed in claim 41.
[0125] On the one hand, the present invention according to aspect
c) solves the problem of providing products having a broad quality
spectrum which varies from their use for food production to their
use in products that are to satisfy the requirements for
pharmaceuticals and the like, for instance.
[0126] On the other hand, the present invention solves this problem
by using the endogenous enzymes of the raw materials and adapting
the production conditions to these enzymes.
[0127] This aspect c) of the invention combines the use of
endogenous enzymes with a technique for recovering specific
size-determined molecules from simple amino acids to large peptides
of slightly less than 10,000 daltons.
[0128] The invention involves retaining the enzymes in the
fermentation process whilst the amino acids and peptides released
are separated off.
[0129] The invention also means that the hydrolysation process can
be run continuously with the addition of more raw materials during
the process.
[0130] The process differs essentially from prior art enzymation
processes in that it is carried out or may be carried out:
[0131] without additives, such as chloroform in order to prevent
undesirable bacterial growth;
[0132] without the addition of sodium hydroxide;
[0133] with the possibility of hot and cold recovery of
protein-free and sterile marine oil/fat;
[0134] with the possibility of controlling the spectrum of free
amino acids and peptides in the end product in selecting raw
materials for the process by choosing of specific raw
materials;
[0135] with the possibility of controlling the result of the
process, as regards amino acid and peptide composition, by means of
the applied process parameters such as temperature and pH;
[0136] without the addition of acid;
[0137] with a flexible combination of different raw materials;
[0138] by using an adapted concentration step for separating off
product fractions; and in that
[0139] by using a continuous enzyme degradation process;
[0140] without coagulation of proteins and/or peptides when using
acid or a base; and
[0141] by size grading of the peptides produced;
[0142] it yields a product that contains minerals and
micronutrients of biological origin.
[0143] Thus, there is provided a method for recovering
peptide/amino acids, minerals and oil or fat from protein materials
preferably of aquatic origin.
[0144] The prior art differs from the present invention by means of
a basically different method for preparing fish proteins, which are
also found in different fractions containing peptides and amino
acids. The production conditions also differ essentially from this
art and with the present invention the use of exogenous enzymes is
avoided. In addition, as also taught in the previously mentioned
cited material, marine oils/fat of high quality are produced by the
present invention by developing a different specific method that is
not described in the prior art.
[0145] The method described is a natural enzymation of proteins
with the object of obtaining dried end products or liquid products
containing different compositions of peptides and free amino acids.
The process yields finished products which optionally contain from
5% to 100% free amino acids. The product does not contain allergens
and DNA traces. There are only very small amounts of fat, typically
less than 0.1%, and biological micronutrients. The method according
to the invention gives a product that is fully useful as culture
media for all types of cultures, including cells from higher
organisms.
[0146] The present invention permits a method without the use of
sodium hydroxide which can result in problems in the production of
amino acids and peptides on an industrial scale. Moreover, the
water ratio can be varied to a greater extent than in the prior
art, and the percentage by weight of free amino acids is also in a
larger range.
[0147] In comparison with this art, both crushed and non-crushed
starting material are used in the present invention, and there is
no addition of a fermentation preparation, but natural enzymes are
used that are already present in the raw material. Thus, the
endogenous enzymes of the raw protein material are used and this
results in a simpler, more stable and less expensive way of
carrying out the hydrolysis. In addition, the conditions must be
directly adapted to the activity conditions of the endogenous
enzymes which are also different from the prior art.
[0148] Another problem found in this industry in that exogenous
enzymes are expensive and may be of varying quality. The present
invention avoids this problem by a recycling of the endogenous
enzymes.
[0149] Furthermore, the active enzymes have a specific cleaning
function. Since they are retained in the filter, these enzymes act
on non-filtered proteins and peptides. The enzymes cause the
breakdown of these materials and therefore the filter has a longer
life compared with the traditional filtering processes used in
hitherto known hydrolysis processes. This is a great advantage as
regards the costs, life time and efficiency of the filters, the
quality of the products and the level of utilisation of the system
or process.
[0150] In addition, the method describes the recovery of oils/fat
and solids. One of the solids that can be obtained by the method
according to the invention is hydroxy apatite. Hydroxy apatite is
used, for example, in biochromatography and other biological
separation processes, in NMR and other detection processes, and is
thus a commercially interesting by-product of the process.
[0151] Choice of technique and process parameters will determine
what end product is obtained. In this way, it will be possible to
adapt products to the customer's requirements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0152] FIG. 1 shows a first embodiment of a plant in which the
hydrolysation process according to aspect a) of the invention is
used.
[0153] FIG. 2 shows a second embodiment of a plant in which the
hydrolysation process according to aspect b) of the invention is
used.
[0154] FIG. 3 shows a third embodiment of a plant in which the
hydrolysation process according to aspect c) of the invention is
used.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0155] The embodiments of the methods according to aspects a) and
b) of the invention respectively are explained in more detail in
the following with reference to FIGS. 1 and 2 respectively.
[0156] The raw materials are pumped in from tank 101; 201 through a
grinding system 102; 202 which gives the desired comminution of the
raw materials.
[0157] Oil/fat from the raw materials can be recovered before the
enzyme process is started. Here, for example, a cold recovery of
the oil could be used. It is also possible not to remove the oil
before enzymation. In that case, the raw materials are pumped
straight to the heat exchanger 105; 205 in by-pass stream D1;
D2.
[0158] Cold recovery of oil can be carried out by:
[0159] 1. centrifuging the raw materials and separating liquid and
solid particles into two different fractions in, for example, a
decanter centrifuge 103; 203;
[0160] 2. separating the oil from the liquid phase stream A1; A2
using, for example, a separator 104; 204;
[0161] 3. mixing the solid phase stream B1; B2 and the heavy phase
from the separation and pumping stream C1; C2 to the fermenter;
[0162] 4. the oil phase from the separation stream D1; D2 can be
pumped to tank 110; 210 via a sterile filter 109; 209 and thus does
not require further refinement in order to attain foodstuff
quality.
[0163] The materials can be pumped via either an "in-line"
continuous heat exchanger 105; 205 or a batch working heat
exchanger to the fermentation tank 106; 206. The fermentation tank
can also be used for heating if this is not done in a heat
exchanger before the materials are pumped in. Added to the raw
materials is a warmed and pH-adjusted water stream E1; E2 which is
heated via a heat exchanger 108; 208 to approximately the
temperature at which the fermentation is to take place. The
adjustment of pH is preferably done by passing the water through a
filter medium that releases calcium 107; 207.
[0164] Temperature and pH are monitored by sensors 111, 111'; 211,
211', or in another manner, in the fermenter during the process.
Adjustment to the desired pH is effected during the process
preferably using bone meal or calcium that is added from storage
tank 112, 212. Nitrogen 113, 213 may also be used for adjusting pH
during the process.
[0165] When the enzymation is finished, the hydrolysate is heated
preferably via a heat exchanger 114; 214, so that the enzymes are
inactivated.
[0166] If the hydrolysate contains bones or other solid particles,
these are removed preferably by using a screen device 115; 215. The
solid particles, stream F1; F2, can be separated into two or more
fractions by means of flotation 116; 216. The heavy fraction 117;
217 consists of bones (hydroxy apatite) that can be dried and/or
used prior to pH adjustment, cf. stream H1; H2. The light
fractions, stream G1; G2, are primarily proteins that are not
hydrolysed.
[0167] These light fractions G1 can be returned to the grinder 102,
as shown in FIG. 1, and used as raw material for a new hydrolysis
process or removed as a by-product.
[0168] As shown in FIG. 2, the light fractions G2 according to
aspect b) of the invention can be passed on separately and mixed
with a concentrate from the concentrator 222. Alternatively, they
can be dried as a separate product.
[0169] The fat that remains after the first fat separation is
separated off using, for example, a three-phase separator 118; 218.
The oil/fat stream I1; I2 is filtered in the filter 119; 219 and
can be taken to the tank 120; 220 for optional subsequent further
processing or the like.
[0170] As shown in FIG. 1, the hydrolysate, stream J1, is passed to
a mixing tank 121 wherein acid 122 (preferably phosphoric acid) is
added until the pH <5. Then calcium 123 is added so that long
peptides and proteins agglomerate. The proteins and calcium/calcium
phosphate are separated off using a centrifuge 124 and are passed
to a tank 125. This by-product can be dried at a high temperature
so that all protein residues are burned off.
[0171] The protein-free hydrolysate stream K1 is concentrated
preferably in a vacuum evaporator 126. The condensate, stream L1,
can be used as additive water, stream E1. The concentrate, stream
M1, can be dried in a spray dryer 127, preferably of the
Filtermate.RTM. type. Alternatively, the concentrate can be
extracted as liquid product stream N1.
[0172] As shown in FIG. 2, the hydrolysate, stream J2, can be
treated using a centrifuge 221 so that the proteins and long
peptides, stream N2, are separated off. These are mixed with the
concentrate, stream M2, of free amino acids and short peptides from
the concentrator 222. The condensate, stream L2, can be used as
additive water, stream E2. The concentrate, stream M2, with admixed
proteins and long peptides, can be dried in a spray dryer 223
preferably of the Filtermate.RTM. type.
[0173] Unless otherwise indicated all percentage disclosures herein
are given in percentages by weight.
[0174] The process is described in more detail below.
[0175] 1) Raw Materials:
[0176] The raw materials for the process may consist of protein
material preferably fish, fish products, shellfish, crustaceans,
molluscs and by-products from fish/the fishing industry, for
example, fish offal, and other marine organisms from fresh water
and salt water. The different raw materials can be used singly or
in a combination of products containing "enzyme material" and
"protein material". The "enzyme material" is the raw material that
contains the endogenous enzymes in a satisfactory amount and of a
satisfactory quality. The "protein material" describes raw
materials that do not contain the endogenous enzymes in a
satisfactory amount and of a satisfactory quality and which must
therefore be supplemented with the enzyme product in order to be
able to carry out the enzyme treatment. In some cases, the enzyme
material may be identical with the protein material. Previously
known processes describe a combination of offal and protein
material in the ratio of 1:1. The method described here makes it
possible to vary this ratio in order to obtain the desired result
in the end product.
[0177] The raw materials meet the statutory requirements for
starting products for the production of foods. Previously, the raw
materials have been classified as scrap by legislation and
definitions. Through good logistics and process routines it will be
possible in this case to have the raw material approved as a
foodstuff. This permits production on an industrial scale and the
use of the product in the food and/or pharmaceuticals industry.
[0178] 2) Pre-treatment of the Raw Materials:
[0179] The raw materials are pumped in from a tank, through a
grinding system, which gives the desired comminution of the
materials. The grinding gives a larger working surface for the
enzymes and it releases the enzymes of the raw materials more
quickly.
[0180] Oil/fat from the raw materials can be recovered before the
enzyme process is started. Here, for example, a cold recovery of
the oil could be used.
[0181] Cold recovery of oil can be done by:
[0182] 1. centrifuging the raw materials and separating liquid and
solid particles into two different fractions;
[0183] 2. separating the oil from the liquid phase;
[0184] 3. mixing the solid phase and the heavy phase from the
separation step and pumping them to the fermenter;
[0185] 4. further processing the oil phase from the separation to
give a finished, customer-specific product that does not require
further refinement in order to attain foodstuff quality.
[0186] The materials can be pumped via either an "in-line"
continuous heat exchanger or in a batch working heat exchanger to
the fermentation tank. The fermentation tank may also be used for
heating if this is not done in a heat exchanger before the
materials are pumped in. If it is desirable to mix different types
of raw materials in a certain ratio, these products can be pumped
in and mixed at the same time. The amount of different raw
materials can be controlled by means of flow meters and/or level
control in the fermenter.
[0187] Moreover, it is possible that the raw materials are not
ground or that the raw materials can avoid being mixed at the same
time, in that a known amount of raw material A is pumped into a
mixing tank and a known amount of raw material B is then pumped
into the same tank.
[0188] It is desirable that the raw materials should be heated to a
temperature that is favourable for the enzymes that are required to
be most active in the hydrolysis process. This temperature range
extends from 40-62.degree. C. The optimal range in most cases will
be 45-58.degree. C. The use of different temperatures will allow
the effect of different enzymes to be obtained and will permit
control of the amino acid composition.
[0189] The invention provides possibilities for the
recovery/separation of the fat during the process, after
hydrolysis, in order to obtain a low fat content in the end
product.
[0190] The fat separation can be done before and/or after
coagulation of the proteins. A typical fat content of the end
product is less than 0.1% in dried peptide/amino acid products.
[0191] Well-known techniques such as decantation, separation and/or
chemical methods can be used for fat separation.
[0192] 3) The Hydrolysis Process:
[0193] The mixture of heated raw materials is pumped into
hydrolysis vessels or tanks. Warmed and pH adjusted water that has
approximately the temperature at which the fermentation is to take
place is added to this mixture. The amount of water can be varied
according to the raw material and desired result. In the prior art
an amount of 50% of the total amount was used, i.e., 50% raw
material and 50% water. In the method according to the invention
less water is used because of an optimisation of available enzyme
and protein material and temperature and pH. This method uses an
amount of from 10% to 40% added water. Optimally, the water added
will be between 20 and 30%. Less added water means that the
concentration of short peptides and free amino acids in the
hydrolysate after hydrolysis is higher, which means a saving in
process and energy costs.
[0194] The hydrolysate is kept in the fermentation tank(s) under
constant stirring and pumping. The purpose of this is to improve
the hydrolysis process. A failure to stir/pump the hydrolysate
during the process could result in there not being sufficient
control of the pH, temperature and the process itself. The
hydrolysis could proceed differently in parts of the hydrolysate
and some of the enzymes could be lost.
[0195] To check how far the hydrolysis has gone, amino-bound
nitrogen is analysed. The analysis can be done either directly in
the fermenter by means of automatic equipment or in a production
laboratory using well-known techniques such as formol titration or
the like. The use of time in the process can vary from 1 to 4
hours. The hydrolysis process is stopped when the percentage of
free amino acids no longer increases in the hydrolysate. This is to
avoid the formation of undesired ammonia, which results in a
reduction of the level of utilisation of the raw materials.
[0196] It is a prerequisite for the process that it is alkaline
enzymes that are at work. It is therefore essential that pH>7.00
during the hydrolysis. The pH range will be between 7.00 and 8.50.
An optimal hydrolysis process is obtained at a pH of 7.60 to 8.20.
If pH >8.1, but <8.4 during the whole process, free
tryptophan is excluded from the amino acid spectrum. Conversely, if
pH<7.6, but >7.4 during the whole process, tryptophan is
maximised to the total it is possible to recover, which is
determined by the raw material. If the temperature is
<46.degree. C. but >44.degree. C. and the pH is <7.8 but
>7.7 during the whole process, collagen is not dissolved to any
great extent, but is obtained in the form of solid particles.
[0197] For pH adjustment of the hydrolysate different bases can be
used, as for instance bone meal from previously recovered fish
bones, calcium and nitrogen/nitrogen gas, but not sodium hydroxide
according to aspect a).
[0198] HCl is not added to the process in the present invention.
The reason for this is that unwanted salts are formed. Also, the
costs of production will be higher. The prior art also describes
chloroform as an additive to prevent bacterial growth. This is not
used in the present process because of the short hydrolysis time.
The use of chloroform on an industrial scale is not desirable, but
possible.
[0199] An elevated temperature, preferably higher than 70 degrees,
is used to stop the hydrolysis. This temperature increase is
preferably effected using an "in-line" heat exchanger.
[0200] Coagulation of residual proteins is effected using a low pH.
Phosphoric acid can then be used as an additive to lower the pH to
the desired level, preferably between pH 3.2 and 5.5. After an
addition of phosphoric acid, optionally in combination with
heating/cooling, it will be possible to remove proteins and
peptides from the hydrolysate. Naturally, other methods for
denaturing proteins and peptides may also be used. For example,
electrical denaturation could be used.
[0201] Known filtration techniques can be used to segment the free
amino acid and short peptide content from denatured proteins and
long peptides. The different weight and different chemical
properties of the fractions can also be used to separate them
during separation. To facilitate this, calcium phosphate, calcium
hydroxide and calcium chloride may be used. This causes proteins
and peptides to "stick together". Thus, they become easier to
separate off owing to their increased density. The amount of
chemicals added will vary, both according to the protein and
peptide content and according to the content of other buffer agents
in the solution.
[0202] 4) Concentration:
[0203] It is then desirable to concentrate the finished
hydrolysate. This is done to remove water prior to the drying
process so that the capacity of the drying step is utilised to the
full. A pre-concentration before drying of up to 70% dry matter
(DM) is possible before crystallisation sets in.
[0204] A distillation process of the vacuum evaporation type is
well suited for this purpose, but any other forms of concentration
devices can be used. The vacuum evaporator concentrates the liquid
at a low temperature, thereby ensuring that the peptides or amino
acids are not damaged.
[0205] Evaporation can take place in the temperature range of
50-85.degree. C. Optimally, the range will be from 65-70.degree. C.
Moreover, the hydrolysate can be passed directly to the drying step
(see point 5) without passing through the concentration step or
concentration may be carried out in other ways than by boiling or
vacuum evaporation. Different types of filtration/ membrane/osmosis
plants could also perform this step.
[0206] 5) Drying/Granulation:
[0207] After concentration, the product can be dried if so desired,
but the product may also exist in liquid form or in any state
between dry and liquid form. Drying makes the product more
storage-stable, and it simplifies logistics and handling. The way
in which the product is dried is of importance for the end result.
A prepared peptide/amino acid product could be highly hygroscopic
and is therefore a challenge as regards this process. To make the
product easier to handle, it is desirable to have a granular
product.
[0208] In one embodiment of this process, drying and granulation
take place in two stages, but one-stage processes are of course
possible. The first stage comprises drying to a powder in a spray
dryer or similar, with a cooling step and then granulation by
adding liquid hydrolysate.
[0209] Granulation is effected in that granulates are "constructed"
by keeping the powder/product in vigorous motion using mechanically
rotating blades which give the product a fluid bed like character.
Then, the concentrate/hydrolysate is sprayed into this mass. This
allows the gradual construction of granulates. This all takes place
as a continuous process. At the end of the granulation process,
dried cold air is blown across or through the granulate. The
granulate is screened and the required fraction extracted.
Remaining fines are recirculated for further granulation.
Excessively large granulates are ground and screened again. Any
newly formed fines are returned to the granulation step.
[0210] As previously mentioned, the drying and granulation process
outlined above is just one of the embodiments that can be used to
dry and granulate the products of the method according to the
invention and anyone of ordinary skill in the art will understand
that any other suitable methods can be used to obtain a similar
result.
[0211] Of course, it is also possible to add various additives to
the product, preferably in the granulation step.
[0212] The carrying out of the invention according to aspect c)
thereof will now be described in more detail.
[0213] The reference numerals in FIG. 3 represent the following
parts of the plant:
[0214] 301=Fermenter
[0215] 302=Separation unit for the removal of solid particles,
preferably a screen
[0216] 303=Separation unit, preferably a centrifuge of the decanter
type
[0217] 304=Flotation tank for separating proteins and hydroxy
apatite
[0218] 305=Separation unit for separating off oil, preferably a
centrifuge
[0219] 306=Filter unit for sterile filtration
[0220] 307=Tank for oil/fat
[0221] 308=Microorganism reduction unit
[0222] 309=Membrane filter unit
[0223] 310=Concentration unit
[0224] 311=Drying unit
[0225] 312=Grinding equipment
[0226] 313=Centrifuge, preferably of the decanter type
[0227] 314=Oil filter
[0228] 315=Tank for oil recovered prior to the hydrolysation
step
[0229] 316=Heat exchanger for heating raw materials
[0230] 317=Calcium dosing unit
[0231] 318=Heat exchanger for heating the water
[0232] 319=Device for supplying bone meal
[0233] 320=Device for adding nitrogen
[0234] 321=Container for recovered bone fraction.
[0235] In addition, FIG. 3 shows, together with the description of
the plant, an embodiment of the process of the invention according
to aspect c), in which the designations represent the following
streams:
[0236] A3=Stream including proteins, enzymes, oil/fat, peptides and
free amino acids. After the microorganism reduction unit 308, the
stream does not contain any solid particles, and has a considerably
reduced proportion of non-hydrolysed proteins and fat if the
separation units 302 and 302 have been used;
[0237] A31=Stream if separation unit 302 is used; after the unit
302 the stream no longer contains solid particles;
[0238] A32=Stream if separation unit 303 is not used;
[0239] B31=Stream including solids removed using screen;
[0240] B32=Stream including solids separated using centrifuge;
[0241] C3=Stream including oil/fat;
[0242] D3=Stream of distillate or the like for release of permeate
from the membrane filter 309;
[0243] E3=Stream of concentrated peptide-amino acid solution to the
drying unit;
[0244] E31=Stream of concentrated peptide-amino acid solution to
packing as a liquid product;
[0245] F3=Stream of raw materials to fermenter 301;
[0246] F31=Stream of raw materials when oil separation does not
take place before the hydrolysis;
[0247] G3=Stream of non-hydrolysed proteins returning to stream
A3;
[0248] H3=Stream of added water;
[0249] I3=Stream of oil recovered before the hydrolysation
step.
[0250] Unless otherwise indicated, all percentage disclosures are
given in percentages by weight.
[0251] The process is described in more detail below:
[0252] 1) Raw Materials:
[0253] The raw materials for the process may consist of protein
materials, preferably fish, fish products, shellfish, crustaceans,
molluscs and by-products from fish or the fishing industry, for
example, fish offal and other marine organisms from fresh water and
salt water. The various raw materials can be used singly or in a
combination of products containing "enzyme material and "protein
material". The "enzyme material" is the raw material containing the
endogenous enzymes in satisfactory quantity and of a satisfactory
quality. The "protein material" describes raw materials that do not
contain the endogenous enzymes in satisfactory quantity and of a
satisfactory quality, and which must therefore be supplemented with
the enzyme material in order to be able to carry out the enzyme
treatment. In some cases, the enzyme material may be identical to
the protein material. Prior art processes describe a combination of
offal and protein material in the ratio 1:1. The method described
in this application makes it possible to vary the ratio in order to
obtain the desired result in the end product.
[0254] The raw materials meet the statutory requirements for
starting products for the production of foods. Previously, the raw
materials have been classified as scrap through legislation and
definitions. Through good logistics and process routines, it will
be possible in this case to have the raw material approved as a
foodstuff. This facilitates production on an industrial scale and
the use of the product in the food processing and/or pharmaceutical
industry.
[0255] 2) Pre-processing of the Raw Materials:
[0256] The raw materials are pumped in from a tank, through a
grinding system 312 which gives the desired comminution of the
materials. The grinding gives a larger working surface for the
enzymes and releases the enzymes of the raw materials.
[0257] A first oil/fat from the raw materials can be recovered
before the enzyme process is started. Here, for example, a cold
recovery of the oil could be used.
[0258] Cold recovery of oil can be carried out by:
[0259] 1. centrifuging 313 the raw materials and separating liquid
and solid particles into two different fractions;
[0260] 2. separating the oil from the liquid phase, cf. 314 and
315;
[0261] 3. mixing the solid phase and the heavy phase from the
separation step and pumping them to the fermenter 301;
[0262] 4. further processing the oil phase from the separation step
to give a finished customer-specific product that does not require
further refinement in order to attain foodstuff quality.
[0263] The raw materials that are added to the fermenter 301 can be
stored in one or more buffer tanks after grinding. Different tanks
can be used for protein material and enzyme material.
[0264] The materials can be pumped via a heat exchanger 316 to the
fermentation tank 301. The fermentation tank 301 can also be used
for heating if this is not done in a heat exchanger before the
materials are pumped in.
[0265] Monitoring of the conditions in the fermenter 301 is done
continuously, either automatically or by manual sampling. The
addition of various additives is done so that the conditions for
the enzymation are kept as constant as possible within the range
that is optimal for the product that is to be produced.
[0266] 3) Enzymation Process:
[0267] Heated raw materials or non-heated raw materials in the form
of protein materials and enzyme materials are pumped into one or
more emzymation tanks. Warmed and pH-adjusted water that has
approximately the temperature at which the fermentation will take
place is added to this mixture. The amount of water can be varied
according to raw material and desired result, depending upon an
optimisation of available enzyme and protein material. The pH is
adjusted by the addition of, for example, nitrogen gas or bone
meal.
[0268] The warmed and pH adjusted mixture of raw material F3 and
water H3 will hereinafter be called "hydrolysate". The hydrolysate
is kept in the fermenter tank 301, optionally under constant and
vigorous stirring. The purpose of this is to enhance the enzymation
process. The hydrolysate is pumped continuously through the system
for removal of the desired amino acids and peptides.
[0269] To keep the conditions for the enzymation constant in the
fermentation tank 301, amino-bound nitrogen, total protein content
and pH are checked regularly.
[0270] Protein material and enzyme material are added as required
throughout the desired duration of the process.
[0271] It is a prerequisite for the process that it is alkaline
enzymes that are at work. It is therefore essential that pH>7.00
during the enzymation. The pH range will be between 7.00 and 8.50.
An optimal enzymation process is obtained at a pH of 7.60 to 8.20.
If pH >8.1, but <8.4 during the whole process, free
tryptophan is excluded from the amino acid spectrum. Conversely, if
pH<7.6, but >7.4 during the whole process, tryptophan is
maximised to the total it is possible to recover, which is
determined by the raw material. If the temperature is
<46.degree. C. but >44.degree. C. and the pH is <7.8 but
>7.7 during the whole process, collagen is not dissolved to any
great extent, but is obtained in the form of solid particles.
[0272] Different bases, such as bone meal from earlier production,
calcium and nitrogen, cf. 319 and 320, can be used for pH
adjustment of the hydrolysate.
[0273] By means of the present invention according to aspect c)
thereof, it is possible to continuously control the enzymation
process by using different parameters in order to maintain the
conditions at an optimal level.
[0274] At the end of the process, the enzyme activity must be
terminated by temperature inactivation or in some other way in
order to prevent ammonification.
[0275] 4) Control of Microorganism Growth:
[0276] The prior art describes chloroform as an additive for
preventing the growth of microorganisms, but it is preferably not
used in this process. In the method according to the invention, UV
or another suitable method that does not coagulate the enzymes is
used to kill bacteria and fungi. This is done to prevent a
substantial growth of microorganisms from consuming the liberated
short peptides and the free amino acids in the formation of new
proteins. Moreover, chloroform on an industrial scale is not
preferred.
[0277] 5) Removal of solid particles:
[0278] The invention involves that solid particles, over a certain
size, can be removed from the hydrolysate either continuously or
periodically by means of a screen system/filter. The screen system
302 can be omitted from or by-pass the system if the decanter
system 303 in the next production stage handles the whole solid
phase removal, or that product A3 which in the present situation is
being processed, does not contain solid particles that are suitable
for screening.
[0279] The removed particles B32 can then be separated according to
density through a flotation process 304 so that protein residues G3
can be fed back to the fermentation tank 301. Proteins float up and
can be skimmed off either mechanically or manually. The heavier
material ends up at the bottom of the flotation tank.
[0280] 6) Decantation of the Hydrolysate:
[0281] A decanter 303 can be used in the system before the oil
separator 305 and the membrane filter 309. This is done to simplify
the separation of fat from the hydrolysate in, for example, a
three-phase separator and thereby reduce the strain on the
subsequent membrane filter.
[0282] A separator does not work optimally if the content of solid
particles is too high, which means that the sludge phase is large.
The decanter is a machine constructed to separate solid particles
of a larger density than the liquid of which they are a part. In
the invention, it is primarily proteins that are separated, and so
it is desirable to pass them back to the fermentation tank for
further enzymation. The separated solid material can be floated
according to the same principle as that used in the screening
system. The same flotation device can be used, if desired. The
decanter 303 may be omitted or disconnected from the system if the
screen device that has already been mentioned handles the desired
separation or that products being treated do not give protein
residues that can be removed using a decanter.
[0283] 7) Separation:
[0284] The hydrolysate is separated using a three-phase separator
305 or other suitable centrifuging method that is suitable for
separating the lighter fat fraction from the hydrolysate. The
separation of fat takes place either continuously or periodically
depending on the amount of fat in the raw materials that are being
processed. A particularly important feature of the present
invention is that a very pure and high-quality fat fraction can be
recovered because the separation can be done continuously
throughout the process so that the fat released is not subjected to
oxidation longer than necessary when the lipoproteins are
decomposed by the hydrolysis. That the hydrolysis takes place under
alkaline conditions also helps to keep the quality of the fat high,
especially when nitrogen is used for pH adjustment.
[0285] 8) Membrane Filtration:
[0286] The invention involves the hydrolysate being pumped through
a device equipped preferably with a membrane filter 309 which
functions in a manner that allows molecules of a certain size to
penetrate the membranes, preferably less than 10,000 daltons. The
filtration is done so that the hydrolysate is either pumped through
a plurality of tubular membranes or past a plurality of planar
membranes.
[0287] The principle of osmosis is used for transport through the
membranes. Concentration of the unfiltered free amino acids and
peptides gives distilled water as a by-product and a part of this
is fed back to the filter at approximately the same pressure as the
hydrolysate on the other side of the membrane. By keeping the
concentration of amino acids and peptides lower on the permeate
side of the membranes, an osmosis-driven penetration through them
will be maintained. The flow of hydrolysate along the membranes
cleans them mechanically of deposits of protein residues and
peptides that are larger than those able to penetrate the
membranes.
[0288] 9) Concentration:
[0289] The finished hydrolysate filtrate must then be concentrated.
This is done to remove water before the drying process so that the
capacity of the drying step is utilised to the full, or that the
concentration level of incoming amino acids and peptides desired in
a liquid product is obtained.
[0290] A distillation process of the vacuum evaporation type is
well suited for this purpose, but any other forms of concentration
devices can be used to remove the desired peptides and amino acids
from the liquid in which they are dissolved during the membrane
filtration. The vacuum evaporator 310 concentrates the liquid at a
low temperature, so that the peptides/amino acids are not damaged.
A prerequisite for the function of the membrane filtration in
earlier stages being optimal is that the concentration device 310
is able to return a distillate that is as pure a possible. Thus,
the osmosis through the membranes will be optimal. Evaporation can
take place in the temperature range of +50-+85.degree. C.
Optimally, this range will be from +65-+70.degree. C. There may be
a risk of the condensate having a temperature that is too high to
be passed back to the filter or the fermentation tank. If this is
the case, a heat exchanger that reduces the temperature to the
desired level must be used.
[0291] 10) Drying:
[0292] After concentration, the product can be dried if so desired,
but it may also be in the form of a liquid product or any form
therebetween. Drying, cf. 311, makes the product more
storage-stable, and it simplifies logistics and handling. The way
in which the product is dried is of importance for the end result.
A prepared peptide/amino acid product could be highly hygroscopic
and is therefore a challenge as regards this process. A high
temperature in the drying process will also cause the product to be
of a more hygroscopic character.
[0293] Drying/granulation will take place in two stages. First, the
product is dried to a powder in a spray dryer or the like, with a
cooling step and then the product is granulated. Granulation is
effected in that granulates are "constructed" by keeping the
powder/product in vigorous motion by means of mechanical
fluidisation. Then, the concentrate/hydrolysate is sprayed into
this mass and the granulates are gradually built up. All this takes
place in a continuous process. At the end of the granulation
process dried cold air is blown across/through the granulate. This
results in it being harder and more readily soluble. The granulate
is then screened and the desired fraction is extracted. Particles
that are too small (fines) are passed back for further granulation,
whilst "oversize" particles are ground and screened again. Any
newly formed fines pass back for regranulation.
[0294] Ordinary conventional spray drying could also be used, but
this gives a fine powder with a large surface. This means that the
product behaves in a highly hygroscopic manner and it is therefore
difficult to handle it in large packages, storage etc.
[0295] Various additives can be added to the product during the
granulation process. Products that are not granulated can also be
produced, as can products that are not dried but simply
concentrated to the desired level.
[0296] Detailed Description of the Function of the Membrane
Filter:
[0297] The filter 309 may be constructed of planar or tubular
filter elements. The filter system is so constructed that the
filtrate, which consists of protein hydrolysate from the fermenter
from which solid particles and fat have been removed, but which
includes an enzyme complex, can freely circulate past the retenate
side of the membranes (crossflow filtering). Thus, a flow is
generated along the surface of the membranes which mechanically
minimises the risk of the formation of a blocking filter cake of
retenate deposited on the membranes. The filtrate circulating on
the retenate side of the filter membranes contains enzymes which
break down the proteins and large peptides that become lodged on
and in the membranes but are too large to penetrate the membranes
to the permeate side. The enzymes are prevented from penetrating
the membranes if the choice of membrane is made so that maximum
molecule size of the permeate is 9,800 daltons. Thus,
non-decomposed proteins are blocked and a protein-free sterile
product is obtained.
[0298] The choice of a membrane with blocking of smaller molecules
will result in a product having smaller peptides and a higher
percentage of free amino acids.
[0299] On the permeate side, a stream of preferably water is made
to pass along the membranes, corresponding to that on the permeate
side. The pressure may be equal on both sides of the membranes,
osmosis driving the permeate through the membranes. Dissolution
takes place in the liquid circulating on the permeate side.
[0300] The requirement for the osmosis to work is that the
concentration of amino acids and peptides is higher on the retenate
side of the membranes. This is achieved by the distillate from the
concentration plant being the liquid that is made to circulate on
the permeate side of the membrane. In principle, this can be
described as a reverse diafiltration where it is on the permeate
side that a pure water additive is used.
[0301] The concentration of the permeate can be done using another
membrane filter arranged for reverse osmosis (RO). The function of
the membrane filter will be the same.
[0302] A series of filters can be used to separate the different
fractions, with regard to maximum peptide size, but in the
succeeding filters there is no help from the enzyme complex to keep
the filter membranes free of filter cake on the retenate side. It
may be advantageous to filter in one stage in order to prevent
blocking.
[0303] Values that have been obtained in laboratory tests using a
dialysis membrane of standard hose-shaped type used in the hospital
area produced by the manufacturer Spectrum Laboratories:
[0304] In tests Spectra/Por 1 Regenerated Cellulose (RC) with
Molecular Weight Cut-Off (MWCO) or 6,000 to 8,000 Daltons (6 k to 8
k MWCO) were used. The flux through these membranes with a total of
DM (dry matter) on the retenate side of 14.7% at a temperature if
48.7.degree. C. and a pH of 7.85 was 3.7 ml/cm2/h at the start.
After 12 hours it was 3.8 ml/cm2/h and after 24 hours it was 3.8
ml/cm2/h. Blocking could not be registered even at 60 hours
operating time. No molecules of more than 9,000 daltons could be
identified in the permeate, with peptide size analysis before and
after concentration of the total of 23 litres of liquid with 36% DM
that was produced during the total of 60 hours. The largest peak on
the spectrogram was from 410-1350 daltons which without correction
gave 42% of the spectrogram area.
* * * * *