U.S. patent application number 12/338446 was filed with the patent office on 2009-06-25 for methods and compositions for digestion of organic waste.
Invention is credited to Lewis A. Spencer, Jeffrey W. Young.
Application Number | 20090162923 12/338446 |
Document ID | / |
Family ID | 40789112 |
Filed Date | 2009-06-25 |
United States Patent
Application |
20090162923 |
Kind Code |
A1 |
Young; Jeffrey W. ; et
al. |
June 25, 2009 |
Methods and Compositions for Digestion of Organic Waste
Abstract
The present invention relates to a process wherein organic
material derived from plant and animal material is processed to
recover nutritional elements. In particular, there is provided a
process for releasing nutritional elements from plant and animal
material comprising the steps of treating the material with one or
more enzymes to digest said material under appropriate conditions
and separating the resulting liquid hydrolysate from the undigested
material.
Inventors: |
Young; Jeffrey W.; (Pompano
Beach, FL) ; Spencer; Lewis A.; (South Dartmouth,
MA) |
Correspondence
Address: |
FOLEY HOAG, LLP;PATENT GROUP, WORLD TRADE CENTER WEST
155 SEAPORT BLVD
BOSTON
MA
02110
US
|
Family ID: |
40789112 |
Appl. No.: |
12/338446 |
Filed: |
December 18, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61015531 |
Dec 20, 2007 |
|
|
|
Current U.S.
Class: |
435/267 |
Current CPC
Class: |
C05F 17/20 20200101;
Y02A 40/216 20180101; Y02A 40/20 20180101; C05F 17/70 20200101;
C13K 1/02 20130101; C05F 5/00 20130101; Y02A 40/209 20180101; Y02P
20/145 20151101; Y02W 30/43 20150501; Y02W 30/40 20150501; C05F
17/986 20200101; C05F 9/00 20130101; C13K 1/06 20130101; Y02A
40/214 20180101; C05F 9/04 20130101 |
Class at
Publication: |
435/267 |
International
Class: |
C12S 3/00 20060101
C12S003/00 |
Claims
1. A process for the release of nutritional elements from organic
waste comprising the steps of: (a) adding to said organic waste at
least one enzyme or at least one mixture of enzymes; (b) incubating
the organic waste of step (a) under appropriate conditions
resulting in at least partial release of the nutritional elements
as a liquid hydrolysate; and (c) separation of the undigested waste
from the resulting liquid hydrolysate.
2. The process of claim 1, wherein the organic waste is fresh food
waste.
3. The process of claim 1, wherein at least two or more, such as
three, four, five, six, seven, eight, nine, or ten enzymes are
added to the organic waste in step (a).
4. The process of claim 3, wherein the two or more enzymes are
added together or sequentially to the organic waste in step
(a).
5. The process of claim 4, wherein the two or more enzymes are
selected from the group consisting of xylanase, asparaginase,
cellulase, hemicellulase, glumayase, beta-glumayase (endo-1,3(4)-),
urease, protease, lipase, amylase, phytase, phosphatase,
aminopeptidase, amylase, carbohydrase, carboxypeptidase, catalase,
chitinase, cutinase, cyclodextrin glycosyltransferase,
deoxyribonuclease, esterase, alpha-galactosidase,
beta-galactosidase, glucoamylase, alpha-amylase, alpha-glucosidase,
beta-glucosidase, haloperoxidase, invertase, laccase, mannosidase,
oxidase, glucose oxidase, pectinolytic enzyme, pectinesterase,
peptidoglutaminase, peroxidase, polyphenoloxidase, proteolytic
enzyme, protease, ribonuclease and transglutaminase.
6. The process of claim 1, wherein the enzymes are selected from
the group consisting of enzymes originating from microbial
fermentation, enzymes derived from a microorganism, and enzymes
derived from plants.
7. The process according to claim 1, wherein the incubating organic
waste of step (b) is under a constant movement.
8. The process according to claim 1, wherein the temperature of the
incubating organic waste of step (b) is between 70.degree. F. and
162.degree. F.
9. The process according to claim 8, wherein the temperature of the
incubating organic waste of step (b) is between 125.degree. F. and
140.degree. F.
10. The process according to claim 1, wherein the incubating
organic waste of step (b) is incubated for between 0 hours and 2.5
hours.
11. The process according to claim 10, wherein the incubating
organic waste of step (b) is incubated for between 45 minutes and
1.5 hours.
12. The process according to claim 1, wherein the incubating
organic waste of step (b) outputs a liquid hydrolysate that is
greater than 70 percent by weight relative to the weight of the
input incubating organic waste.
13. The process according to claim 13, wherein the incubating
organic waste of step (b) outputs a liquid hydrolysate that is
greater than 90 percent by weight relative to the weight of the
input incubating organic waste.
14. The process according to claim 1, wherein the separation step
of step (c) excludes undigested material of greater than 1
millimeter in diameter from the liquid hydrolysate.
15. The process according to claim 14, wherein the separation step
of step (c) excludes undigested material of greater than 0.5
millimeter in diameter from the liquid hydrolysate.
16. A process for the release of nutritional elements from organic
waste comprising the steps of: (a) adding to said organic waste at
least one enzyme or at least one mixture of enzymes; (b) incubating
the organic waste of step (a) under appropriate conditions
resulting in at least partial release of the nutritional elements
as a liquid hydrolysate; (c) separation of the undigested waste
from the resulting liquid hydrolysate; and (d) stabilization of the
liquid hydrolysate resulting from step (c).
17. The process of claim 16, wherein the organic waste is fresh
food waste.
18. The process of claim 16, wherein at least two or more, such as
three, four, five, six, seven, eight, nine, or ten enzymes are
added to the organic waste in step (a).
19. The process of claim 18, wherein the two or more enzymes are
added together or sequentially to the organic waste in step
(a).
20. The process of claim 19, wherein the two or more enzymes are
selected from the group consisting of xylanase, asparaginase,
cellulase, hemicellulase, glumayase, beta-glumayase (endo-1,3(4)-),
urease, protease, lipase, amylase, phytase, phosphatase,
aminopeptidase, amylase, carbohydrase, carboxypeptidase, catalase,
chitinase, cutinase, cyclodextrin glycosyltransferase,
deoxyribonuclease, esterase, alpha-galactosidase,
beta-galactosidase, glucoamylase, alpha-amylase, alpha-glucosidase,
beta-glucosidase, haloperoxidase, invertase, laccase, mannosidase,
oxidase, glucose oxidase, pectinolytic enzyme, pectinesterase,
peptidoglutaminase, peroxidase, polyphenoloxidase, proteolytic
enzyme, protease, ribonuclease and transglutaminase.
21. The process of claim 16, wherein the enzymes are selected from
the group consisting of enzymes originating from microbial
fermentation, enzymes derived from a microorganism, and enzymes
derived from plants.
22. The process according to claim 16, wherein the incubating
organic waste of step (b) is under a constant movement.
23. The process according to claim 16, wherein the temperature of
the incubating organic waste of step (b) is 70.degree. F. and
162.degree. F.
24. The process according to claim 23, wherein the temperature of
the incubating organic waste of step (b) is 125.degree. F. and
140.degree. F.
25. The process according to claim 16, wherein the incubating
organic waste of step (b) is incubated for 0 and 2.5 hours.
26. The process according to claim 25, wherein the incubating
organic waste of step (b) is incubated for 45 minutes and 1.5
hours.
27. The process according to claim 16, wherein the incubating
organic waste of step (b) outputs a liquid hydrolysate that is
greater than 70 percent by weight relative to the weight of the
input incubating organic waste.
28. The process according to claim 27, wherein the incubating
organic waste of step (b) outputs a liquid hydrolysate that is
greater than 90 percent by weight relative to the weight of the
input incubating organic waste.
29. The process according to claim 16, wherein the separation step
of step (c) excludes undigested material of greater than 1
millimeter in diameter from the liquid hydrolysate.
30. The process according to claim 29, wherein the separation step
of step (c) excludes undigested material of greater than 0.5
millimeter in diameter from the liquid hydrolysate.
31. The process according to claim 16, wherein the stabilization
step of step (d) comprises addition and mixing of the liquid
hydrolysate with an acid source.
32. The process according to claim 31, wherein the acid source is
selected from the group consisting of hydrochloric, sulfuric,
phosphoric, acetic, stearic, propionic, tartaric, maleic, benzoic,
or succinic acids.
33. The process according to claim 31, wherein the pH of the liquid
hydrolysate is less than 7.0.
34. The process according to claim 33, wherein the pH of the liquid
hydrolysate is 3.5.
35. A process for the release of nutritional elements from organic
waste comprising the steps of: (a) adding to said organic waste at
least one enzyme or at least one mixture of enzymes; (b) incubating
the organic waste of step (a) under appropriate conditions
resulting in at least partial release of the nutritional elements
as a liquid hydrolysate; (c) coarse separation of the undigested
waste from the resulting liquid hydrolysate; (d) stabilization of
the liquid hydrolysate resulting from step (c); and (e) fine
separation of the undigested waste from the resulting liquid
hydrolysate.
36. The process of claim 35, wherein the organic waste is fresh
food waste.
37. The process of claim 35, wherein at least two or more, such as
three, four, five, six, seven, eight, nine, or ten enzymes are
added to the organic waste in step (a).
38. The process of claim 37, wherein the two or more enzymes are
added together or sequentially to the organic waste in step
(a).
39. The process of claim 38, wherein the two or more enzymes are
selected from the group consisting of xylanase, asparaginase,
cellulase, hemicellulase, glumayase, beta-glumayase (endo-1,3(4)-),
urease, protease, lipase, amylase, phytase, phosphatase,
aminopeptidase, amylase, carbohydrase, carboxypeptidase, catalase,
chitinase, cutinase, cyclodextrin glycosyltransferase,
deoxyribonuclease, esterase, alpha-galactosidase,
beta-galactosidase, glucoamylase, alpha-amylase, alpha-glucosidase,
beta-glucosidase, haloperoxidase, invertase, laccase, mannosidase,
oxidase, glucose oxidase, pectinolytic enzyme, pectinesterase,
peptidoglutaminase, peroxidase, polyphenoloxidase, proteolytic
enzyme, protease, ribonuclease and transglutaminase.
40. The process of claim 35, wherein the enzymes are selected from
the group consisting of enzymes originating from microbial
fermentation, enzymes derived from a microorganism, and enzymes
derived from plants.
41. The process according to claim 35, wherein the incubating
organic waste of step (b) is under a constant movement.
42. The process according to claim 35, wherein the temperature of
the incubating organic waste of step (b) is 70.degree. F. and
162.degree. F.
43. The process according to claim 42, wherein the temperature of
the incubating organic waste of step (b) is 125.degree. F. and
140.degree. F.
44. The process according to claim 35, wherein the incubating
organic waste of step (b) is incubated for between 0 hours and 2.5
hours.
45. The process according to claim 44, wherein the incubating
organic waste of step (b) is incubated for between 45 minutes and
1.5 hours.
46. The process according to claim 35, wherein the incubating
organic waste of step (b) outputs a liquid hydrolysate that is
greater than 70 percent by weight relative to the weight of the
input incubating organic waste.
47. The process according to claim 46, wherein the incubating
organic waste of step (b) outputs a liquid hydrolysate that is
greater than 90 percent by weight relative to the weight of the
input incubating organic waste.
48. The process according to claim 35, wherein the separation step
of step (c) excludes undigested material of greater than 1
millimeter in diameter from the liquid hydrolysate.
49. The process according to claim 48, wherein the separation step
of step (c) excludes undigested material of greater than 0.5
millimeter in diameter from the liquid hydrolysate.
50. The process according to claim 35, wherein the stabilization
step of step (d) comprises addition and mixing of the liquid
hydrolysate with an acid source.
51. The process according to claim 50, wherein the acid source is
selected from the group consisting of hydrochloric, sulfuric,
phosphoric, acetic, stearic, propionic, tartaric, maleic, benzoic,
or succinic acids.
52. The process according to claim 50, wherein the pH of the liquid
hydrolysate is less than 7.0.
53. The process according to claim 52, wherein the pH of the liquid
hydrolysate is 3.5.
54. The process according to claim 35, wherein the separation step
of step (e) excludes undigested material of greater than 300
microns in diameter from the liquid hydrolysate.
55. The process according to claim 54, wherein the separation step
of step (e) excludes undigested material of greater than 149
microns in diameter from the liquid hydrolysate.
56. The process according to claims 1, 16, or 35, wherein the
organic waste of step (a) is first ground into particles less than
3/8 inch in diameter.
57. The process according to claims 1, 16, or 35, wherein the
liquid hydrolysate is used as a nutraceutical, organic fertilizer,
pharmaceutical, aquaculture feed, animal feed, or biostimulant.
Description
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application Ser. No. 61/015,531, filed on Dec. 20, 2007; the entire
contents of the application is incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] The processing and disposal of organic waste streams are
increasingly important topics of environmental, economical and
technological concern. Organic waste is generated from different
activities, such as industrial activities (e.g., organic waste from
food processing manufacturers, restaurants, and grocery stores),
agricultural activities (e.g., organic waste from gardens, farms,
or cattle farms), and domestic activities (e.g., household waste).
There are increasing problems in the handling of these plant and
animal organic waste streams due to the continuously increasing
amount produced. The problems are global in nature, but are
particular acute in areas with very dense human populations and in
areas with intense livestock production.
[0003] Traditional solutions to the problem of disposing of organic
waste, such as landfill, incineration, or composting, are
associated with various problems, e.g., processing space, building
and operating costs, consumption of time resources, and
environmental pollution. Thus, there is an environmental and
industrial need to find methods and processes that, as opposed to
disposal, allow for the recovery, release and/or utilization of the
valuable nutrients in organic waste.
[0004] In this respect, several solutions have been proposed in the
art. However, none is suitable for the processing of fresh organic
waste, e.g., fresh food waste, as presented, for example, in
supermarket organic waste, into nutrients that are in a
bioavailable form. For example, discussed in US Publication
26194299 (Brinch-Pedersen et al.) is a method for recycling slurry
or sewage waste material (e.g., manure) derived from human, animal
and industrial areas which must first be separated into liquid and
solid fractions. U.S. Pat. No. 6,121,032 (Cooney Jr. et al.)
teaches processes and compositions which may be used for
facilitating the decomposition of foodstuff waste solids which are
to be provided to a sewage treatment system (e.g., garbage disposal
and septic tanks).
[0005] In contrast to the above-identified solutions proposed in
the art, it is one signifimayt object of the present invention to
provide a process for releasing and recycling important nutritional
elements derived from organic waste in a bioavailable form. The
inventors of the present invention have found that there is a large
potential for using various kinds of enzymes for solubilizing
important nutritional elements present in organic waste (e.g.,
fresh food waste), thereby facilitating the release and increased
availability of the important nutritional elements in a
bioavailable form.
[0006] The process of the invention has the advantages of being
capable of 1) giving a very high degree of released valuable
nutritional elements from organic waste, including undenatured
protein, natural oils, active enzymes, plant hormones, aerobic
bacteria, and aerobic fungi, 2) reducing the overall cost and time
for the treatment of waste, 3) increasing environmental
sustainability and 4) sequestering of the carbon molecules.
[0007] In particular, the sequestering of the carbon molecules is
accomplished by keeping the carbon within the end product in
accordance with the following principles:
[0008] 1. The use of fresh organic waste with minimized
decomposition prevents the formation of gas (e.g., carbon dioxide
(CO.sub.2) and/or methane (CH.sub.4)). Therefore, at the start of
the enzymatic digestion processes as described herein, all of the
original carbon content of the organic waste (e.g., fresh food
waste) is present;
[0009] 2. The process is done rapidly and aerobically. in order to
minimize decomposition;
[0010] 3. The resulting hydrolysate may be stabilized (e.g., using
acid stabilization) such that decomposition of the enzymatically
digested organic material has been minimized and stabilized and is
therefore still `fresh` when it is applied to the soil;
[0011] 4. The resulting hydrolysate may be applied to soil as a
fertilizer and this `fresh` product--hydrolyzed food in its natural
state--may become food for aerobic soil microbes living in the root
zone of the plant. Soil microbes may turn the carbon in this
material into plant available nutrients. The carbon is taken up
directly into the plant and converted into plant material such that
the carbon originally present in the initial organic waste is
sequestered and incorporated back into plants; and
[0012] 5. By supplanting the use of petro-chemical fertilizers
and/or compost, carbon sequestration accomplished as described
herein helps to prevent the leaching of carbon into the water
supply or into the atmosphere by the 50-80% of all chemical
fertilizers, including reduction of ammonia volatilization, which
turns urea into ammonia gas, and denitrification, where nitrate-N
is converted into gaseous forms (nitric oxide, nitrous oxide,
dinitrogen). Similarly, supplanting of composting produces similar
benefits as a typical compost pile will reduce its size by 50%, of
which some signifimayt portion is due to the leaching of carbon
into the groundwater and more still is gassed off as carbon dioxide
and methane.
SUMMARY OF THE INVENTION
[0013] The present invention is based, in part, on the discovery
that the processes described herein provide for releasing and
recycling important nutritional elements derived from organic waste
in a bioavailable form.
[0014] Accordingly, in one aspect, the invention features a process
for the release of nutritional elements from organic waste
comprising the steps of: (a) adding to said organic waste at least
one enzyme or at least one mixture of enzymes; (b) incubating the
organic waste of step (a) under appropriate conditions resulting in
at least partial release of the nutritional elements as a liquid
hydrolysate; and (c) separation of the undigested waste from the
resulting liquid hydrolysate. In one embodiment, the organic waste
is fresh food waste.
[0015] The enzymes used in step (a) may comprise at least two or
more, e.g., three, four, five, six, seven, eight, nine, or ten
enzymes. The two or more enzymes may be added together or
sequentially to the organic waste in step (a). In another aspect,
the two or more enzymes may be selected from the group consisting
of xylanase, asparaginase, cellulase, hemicellulase, glumayase,
beta-glumayase (endo-1,3(4)-), urease, protease, lipase, amylase,
phytase, phosphatase, aminopeptidase, amylase, carbohydrase,
carboxypeptidase, catalase, chitinase, cutinase, cyclodextrin
glycosyltransferase, deoxyribonuclease, esterase,
alpha-galactosidase, beta-galactosidase, glucoamylase,
alpha-amylase, alpha-glucosidase, beta-glucosidase, haloperoxidase,
invertase, laccase, mannosidase, oxidase, glucose oxidase,
pectinolytic enzyme, pectinesterase, peptidoglutaminase,
peroxidase, polyphenoloxidase, proteolytic enzyme, protease,
ribonuclease and transglutaminase. These enzymes may be selected,
for example, from the group consisting of enzymes originating from
microbial fermentation, enzymes derived from a microorganism, and
enzymes derived from plants.
[0016] The incubating organic waste of step (b) may be under
constant movement. In another aspect, the temperature of the
incubating organic waste of step (b) is between 70.degree. F. and
162.degree. F. (e.g., between 125.degree. F. and 140.degree. F.).
In yet another aspect, the incubating organic waste of step (b) may
be incubated for between 0 hours and 2.5 hours (e.g., between 45
minutes and 1.5 hours). In one embodiment, the incubating organic
waste of step (b) may output a liquid hydrolysate that is greater
than 70 percent (e.g., greater than 90 percent) by weight relative
to the weight of the input incubating organic waste.
[0017] The process separation step of step (c) may exclude
undigested material of greater than 0.5 millimeters (e.g., greater
than 1 mm) in diameter from the liquid hydrolysate.
[0018] In another aspect, the invention features a process for the
release of nutritional elements from organic waste comprising the
steps of: (a) adding to said organic waste at least one enzyme or
at least one mixture of enzymes; (b) incubating the organic waste
of step (a) under appropriate conditions resulting in at least
partial release of the nutritional elements as a liquid
hydrolysate; (c) separation of the undigested waste from the
resulting liquid hydrolysate. In one embodiment, the organic waste
is fresh food waste; and (d) stabilization of the liquid
hydrolysate resulting from step (c).
[0019] The enzymes used in step (a) may comprise at least two or
more, e.g., three, four, five, six, seven, eight, nine, or ten
enzymes. The two or more enzymes may be added together or
sequentially to the organic waste in step (a). In another aspect,
the two or more enzymes may be selected from the group consisting
of xylanase, asparaginase, cellulase, hemicellulase, glumayase,
beta-glumayase (endo-1,3(4)-), urease, protease, lipase, amylase,
phytase, phosphatase, aminopeptidase, amylase, carbohydrase,
carboxypeptidase, catalase, chitinase, cutinase, cyclodextrin
glycosyltransferase, deoxyribonuclease, esterase,
alpha-galactosidase, beta-galactosidase, glucoamylase,
alpha-amylase, alpha-glucosidase, beta-glucosidase, haloperoxidase,
invertase, laccase, mannosidase, oxidase, glucose oxidase,
pectinolytic enzyme, pectinesterase, peptidoglutaminase,
peroxidase, polyphenoloxidase, proteolytic enzyme, protease,
ribonuclease and transglutaminase. These enzymes may be selected,
for example, from the group consisting of enzymes originating from
microbial fermentation, enzymes derived from a microorganism, and
enzymes derived from plants.
[0020] The incubating organic waste of step (b) may be under
constant movement. In another aspect, the temperature of the
incubating organic waste of step (b) is between 70.degree. F. and
162.degree. F. (e.g., between 125.degree. F. and 140.degree. F.).
In yet another aspect, the incubating organic waste of step (b) may
be incubated for between 0 hours and 2.5 hours (e.g., between 45
minutes and 1.5 hours). In one embodiment, the incubating organic
waste of step (b) may output a liquid hydrolysate that is greater
than 70 percent (e.g., greater than 90 percent) by weight relative
to the weight of the input incubating organic waste.
[0021] The process separation step of step (c) may exclude
undigested material of greater than 0.5 millimeters (e.g., greater
than 1 mm) in diameter from the liquid hydrolysate.
[0022] The process stabilization step of step (d) may comprise
addition and mixing of the liquid hydrolysate with an acid source.
In one embodiment, the acid source may be selected from the group
consisting of hydrochloric, sulfuric, phosphoric, acetic, stearic,
propionic, tartaric, maleic, benzoic, or succinic acids. In another
embodiment, the pH of the liquid hydrolysate is less than 7.0
(e.g., the pH of the liquid hydrolysate is 3.5).
[0023] In yet another aspect, the invention features a process for
the release of nutritional elements from organic waste comprising
the steps of: (a) adding to said organic waste at least one enzyme
or at least one mixture of enzymes; (b) incubating the organic
waste of step (a) under appropriate conditions resulting in at
least partial release of the nutritional elements as a liquid
hydrolysate; (c) coarse separation of the undigested waste from the
resulting liquid hydrolysate. In one embodiment, the organic waste
is fresh food waste; (d) stabilization of the liquid hydrolysate
resulting from step (c); and (e) fine separation of the undigested
waste from the resulting liquid hydrolysate.
[0024] The enzymes used in step (a) may comprise at least two or
more, e.g., three, four, five, six, seven, eight, nine, or ten
enzymes. The two or more enzymes may be added together or
sequentially to the organic waste in step (a). In another aspect,
the two or more enzymes may be selected from the group consisting
of xylanase, asparaginase, cellulase, hemicellulase, glumayase,
beta-glumayase (endo-1,3(4)-), urease, protease, lipase, amylase,
phytase, phosphatase, aminopeptidase, amylase, carbohydrase,
carboxypeptidase, catalase, chitinase, cutinase, cyclodextrin
glycosyltransferase, deoxyribonuclease, esterase,
alpha-galactosidase, beta-galactosidase, glucoamylase,
alpha-amylase, alpha-glucosidase, beta-glucosidase, haloperoxidase,
invertase, laccase, mannosidase, oxidase, glucose oxidase,
pectinolytic enzyme, pectinesterase, peptidoglutaminase,
peroxidase, polyphenoloxidase, proteolytic enzyme, protease,
ribonuclease and transglutaminase. These enzymes may be selected,
for example, from the group consisting of enzymes originating from
microbial fermentation, enzymes derived from a microorganism, and
enzymes derived from plants.
[0025] The incubating organic waste of step (b) may be under
constant movement. In another aspect, the temperature of the
incubating organic waste of step (b) is between 70.degree. F. and
162.degree. F. (e.g., between 125.degree. F. and 140.degree. F.).
In yet another aspect, the incubating organic waste of step (b) may
be incubated for between 0 hours and 2.5 hours (e.g., between 45
minutes and 1.5 hours). In one embodiment, the incubating organic
waste of step (b) may output a liquid hydrolysate that is greater
than 70 percent (e.g., greater than 90 percent) by weight relative
to the weight of the input incubating organic waste.
[0026] The process separation step of step (c) may exclude
undigested material of greater than 0.5 millimeters (e.g., greater
than 1 mm) in diameter from the liquid hydrolysate.
[0027] The process stabilization step of step (d) may comprise
addition and mixing of the liquid hydrolysate with an acid source.
In one embodiment, the acid source may be selected from the group
consisting of hydrochloric, sulfuric, phosphoric, acetic, stearic,
propionic, tartaric, maleic, benzoic, or succinic acids. In another
embodiment, the pH of the liquid hydrolysate is less than 7.0
(e.g., the pH of the liquid hydrolysate is 3.5).
[0028] The process separation step of step (e) may exclude
undigested material of greater than 149 microns (e.g., greater than
300 microns) in diameter from the liquid hydrolysate.
[0029] In still another aspect of the invention, the organic waste
to be digested in any of the processes described herein may first
be ground into particles prior to enzymatic digestion (e.g., first
ground into particles less than 3/8 inch in diameter). In another
embodiment, the liquid hydrolysate resulting from any of the
processes described herein may be used as a nutraceutical, organic
fertilizer, pharmaceutical, aquaculture feed, animal feed, or
biostimulant. In still another embodiment, the liquid hydrolysate
resulting from any of the processes described herein may be used as
an enhanced feedstock of bioavailable nutrients for anaerobic or
aerobic fermentation useful for the production of chemicals (e.g.,
biogases, biofuels, and alcohols).
[0030] In yet another aspect, the present invention provides an
enzyme mixture comprising at least two enzymes, e.g., such as
three, four, five, six, seven, eight, nine or ten enzymes, selected
from the group consisting of xylanase, asparaginase, cellulase,
hemicellulase, glumayase, beta-glumayase (endo-1,3(4)-), urease,
protease, lipase, amylase, phytase, phosphatase, aminopeptidase,
amylase, carbohydrase, carboxypeptidase, catalase, chitinase,
cutinase, cyclodextrin glycosyltransferase, deoxyribonuclease,
esterase, alpha-galactosidase, beta-galactosidase, glucoamylase,
alpha-amylase, alpha-glucosidase, beta-glucosidase, haloperoxidase,
invertase, laccase, mannosidase, oxidase, pectinolytic enzyme,
peptidoglutaminase, peroxidase, polyphenoloxidase, proteolytic
enzyme, protease, ribonuclease and transglutaminase, or
combinations thereof.
[0031] In a still further aspect, the invention relates to the use
of the enzyme mixture according to the invention for releasing
nutritional elements from organic waste according to any of the
processes described herein.
DETAILED DESCRIPTION OF THE INVENTION
[0032] It is a primary object of the present invention to provide a
process for releasing and recycling important nutritional elements
derived from organic waste in a bioavailable form.
[0033] The inventors of the present invention have found that it is
possible to utilize the resources present in organic waste by
turning them into important and valuable nutritional elements. The
methods and compositions of the invention allow the release of
nutritional elements from organic waste through treatment with
enzymes that, for example, and without limitation, degrade fats and
oils (e.g., lipases), protein (e.g., proteases), starch (e.g.,
carbohydrases), sugars (e.g., glucose oxidases), fruit/pectin
(e.g., pectinesterases), cellulose (e.g., cellulases), and/or
hemicellulose (e.g., hemicellulases).
[0034] In addition, the inventors realized that bioavailability of
the released nutrients derived from the enzymatically digested
organic material may be improved by incorporating the step of
stabilizing the liquid hydrolysate that is reacted by the enzymatic
digestion of the organic material.
[0035] One will realize that the fresh organic material to be
digested may be an important element for the methods of the present
invention, in order to recycle important nutritional elements
within using an enzymatic digestion process.
[0036] Thus, in an aspect of the present invention, there is
provided a process for releasing nutritional elements from organic
waste, the process comprising the steps of:
[0037] (a) adding to said organic waste at least one enzyme or at
least one mixture of enzymes;
[0038] (b) incubating the organic waste of step (a) under
appropriate conditions resulting in at least partial release of the
nutritional elements as a liquid hydrolysate; and
[0039] (c) separation of the undigested waste from the resulting
liquid hydrolysate.
[0040] In another embodiment, the process according to the
invention, comprises the steps of:
[0041] (a) adding to said organic waste at least one enzyme or at
least one mixture of enzymes;
[0042] (b) incubating the organic waste of step (a) under
appropriate conditions resulting in at least partial release of the
nutritional elements as a liquid hydrolysate;
[0043] (c) separation of the undigested waste from the resulting
liquid hydrolysate; and
[0044] (d) stabilization of the liquid hydrolysate resulting from
step (c).
[0045] In yet a further embodiment, the process according to the
invention, comprises the steps of:
[0046] (a) adding to said organic waste at least one enzyme or at
least one mixture of enzymes;
[0047] (b) incubating the organic waste of step (a) under
appropriate conditions resulting in at least partial release of the
nutritional elements as a liquid hydrolysate;
[0048] (c) coarse separation of the undigested waste from the
resulting liquid hydrolysate;
[0049] (d) stabilization of the liquid hydrolysate resulting from
step (c); and
[0050] (e) fine separation of the undigested waste from the
resulting liquid hydrolysate.
[0051] In some embodiments of the present invention the nutritional
elements or nutrients are selected from the group consisting of
plant nutrients, metals, minerals, carbohydrates, peptides, and
oils. In other embodiments, the plant nutrients are selected from
the group consisting of phosphate, calcium, potassium, and
nitrogen. In yet another embodiment of the present invention, the
plant nutrient is phosphate, such as organic phosphate or inorganic
orthophosphate.
[0052] In the present context, the terms "waste" and "organic
waste" are used interchangeably and refer to any type of discarded
organic material derived from human, animal or industrial areas. In
one embodiment, the waste is selected from the group consisting of
municipal sewage, household waste, slaughterhouse waste, human
waste, plant waste such as from gardening, animal waste and
industrial waste such as waste from the food, feed and
pharmaceutical industry, e.g. waste from fermentation processes,
brewing or production of recombinant enzymes. The waste may be
provided from waste holding facilities, i.e., facilities for
holding, storage or treatment of waste, including pits or lagoon
where animal waste is stored. In the present context, the terms
"fresh food waste" and "fresh food organic waste" are used
interchangeably and refer to waste which has the following
characteristics: 1. the fresh food waste is substantially firm with
a shiny color, 2. any flesh will substantially spring back when
pressed, 3. the fresh food waste is substantially free of
discoloration or darkening around the edges, 4. the fresh food
waste will smell substantially fresh and be substantially free of
any ammonia, "rotten egg," "fishy," or other foul smell, 5. juice
will not have substantially seeped from a substantial amount of
fruit, and 6. the fresh food waste has been kept substantially at
an appropriate temperature (e.g., constant refrigeration) to
maintain freshness. By contrast, "decomposition" or "decomposing
waste" refers to processes or material for which at least one of
the following characteristics is present: 1. the waste is
substantially soft with a dull color, 2. any flesh will not
substantially spring back when pressed or has lost its shape or
firmness, 3. the waste has substantial darkening around the edges,
or substantial brown, black, green or yellow discoloration, 4. the
waste emits a substantial foul odor, including, but not limited to
the scent of ammonia, "rotten egg," "fishy," vinegar, yeast, or
mold, 5. fungal (mold) or bacterial growth is substantially
present, or 6. the waste has not substantially been kept at an
appropriate temperature to ensure freshness. With regard to these
criteria, the terms "substantial" and "substantially" may refer to
50%, 55%, 60%, 65%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%,
79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%,
92%, 93%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, or
greater of the organic waste as a whole or characteristic of
particular elements of the organic waste under consideration.
[0053] The use of fresh food waste may be critical for obtaining as
high a content of nutrients as possible from the waste. Through
careful observation, the present inventors have identified
processes that minimize decomposition of organic waste such that it
is kept in a fresh state. In one embodiment, the processes of the
invention involves the use of organic waste, e.g., fresh food
waste, specifically subjected to handling conditions that minimize
degradation, decomposition, or an initial release of nutrients and
carbohydrates. In one embodiment, the fresh food waste may be
provided from waste holding facilities, e.g. facilities for
holding, storage or treatment of fresh food waste, including
supermarket facilities. For example, pre-weighed containers may be
filled with fresh food waste such that the weight of the fresh food
waste contents is known and tracked (e.g., by a barcode and/or
computer tracking system). The containers may be cleaned and
sterilized prior to being used to collect fresh food waste
according to methods well known in the art. In another embodiment,
the containers may be insulated in order to help ensure appropriate
temperatures required to maintain freshness, and/or hold relatively
small volumes of fresh food waste (e.g., 1,000 pounds or less),
and/or have sealable lids to help ensure freshness. In still other
embodiments, the containers may be collected frequently (e.g.,
three days per week) and transported to a processing facility,
optionally, using refrigerated conditions during transport (e.g.,
refrigerated trucks). The organic waste, e.g., fresh food waste,
may optionally be source separated into separate categories of
waste, e.g., vegetable waste versus animal meat waste. In the food
industry, the term "source separation" typically refers to the
sequestration of trash components (e.g., paper, plastic, "rubbish",
cardboard, glass, newspaper, and aluminum and steel mays) away from
organic waste. In addition to this common definition within the
art, the term "source separation" may alternatively refer to the
sequestration of different types of organic waste streams (e.g.,
bakery, deli, seafood, produce, and packaged goods) whether they
contain trash components or not. Through careful observation, the
present inventors determined that isolation of different types of
organic waste streams allows for the production of consistent and
defined commingled raw material for enhanced digestion by the
enzymes described herein. In this respect, the proportion of trash
components present within the raw organic material to be digested
may be 1%, 2%, 3%, 4%, 5%, 10%, 20%, 30%, 40%, 50%, or more by
weight or volume of the raw organic material or any range in
between to be digested since these components will subsequently be
removed when the resulting liquid hydrolysate is separated from the
undigested waste. In addition, the organic waste to be
enzymatically digested, e.g., fresh food waste, does not need to be
separated according to liquid and solid phases.
[0054] Optionally, the organic waste, e.g., fresh food waste, is
ground into particles of a defined average size. The ground
particles, on average, may have a length of any side less than 10
inches, 9 inches, 8 inches, 7 inches, 6 inches, 5 inches, 4 inches,
3 inches, 2 inches, 1 inch, 7/8 inch, 3/4 inch, 5/8 inch, 1/2 inch,
3/8 inch, 1/4 inch, 1/8 inch, 1/16 inch or less.
[0055] In a further step of the present invention, the organic
waste, e.g., fresh food waste, is subjected to an enzymatic
digestion step, which is achieved by treatment with one or more
appropriate enzymes. In one embodiment, two or more enzymes, e.g.,
three, four, five, six, seven, eight, nine or ten enzymes, are
added to the organic waste, e.g., fresh food waste.
[0056] In another embodiment, the enzyme(s) is selected from the
group consisting of xylanase, asparaginase, cellulase,
hemicellulase, glumayase, beta-glumayase (endo-1,3(4)-), urease,
protease, lipase, amylase, phytase, phosphatase, aminopeptidase,
amylase, carbohydrase, carboxypeptidase, catalase, chitinase,
cutinase, cyclodextrin glycosyltransferase, deoxyribonuclease,
esterase, alpha-galactosidase, beta-galactosidase, glucoamylase,
alpha-amylase, alpha-glucosidase, beta-glucosidase, haloperoxidase,
invertase, laccase, mannosidase, oxidase, glucose oxidase,
pectinolytic enzyme, pectinesterase, peptidoglutaminase,
peroxidase, polyphenoloxidase, proteolytic enzyme, protease,
ribonuclease and transglutaminase, or combinations hereof. The
addition of xylanase, asparaginase, glumayase, beta-glumayase
(endo-1,3(4)-) and cellulase results in a degradation of the cell
wall of the lignocellulosic material present in the waste, whereas
the protease degrades protein, lipase degrades lipid and starch is
degraded by the addition of amylase and carbohydrase. The skilled
artisan will appreciate that particular enzymes with substantially
the same functions as those enzymes listed above are well known in
the art, including the parameters required for determining optimal
enzymatic activity and determining cohabitability with other
enzymes such that all enzymes that cohabitat are functionally
active. For example, 0.01 g, 0.05 g, 0.1 g, 0.15 g, 0.2 g, 0.25 g,
0.3 g, 0.35 g, 0.4 g, 0.45 g, 0.5 g, 0.55 g, 0.6 g, 0.65 g, 0.7 g,
0.75 g, 0.8 g, 0.85 g, 0.9 g, 0.95 g, 1.0 g (i.e., the weight of 50
mL of enzyme given that the density of the enzymes solutions is
similar to that of water), 1.05 g, 1.1 g, 1.15 g, 1.20 g, 1.25 g,
1.30 g, 1.35 g, 1.40 g, 1.45 g, 1.50 g, 1.55 g, 1.60 g, 1.65 g,
1.70 g, 1.75 g, 1.80 g, 1.85 g, 1.90 g, 1.95 g, 2.00 g, or more or
any range in between of per each enzyme(s) (e.g., Asparaginase
(3,500 ASNU/g, Acrylaway.RTM. L, Novozymes, Inc.), Beta-glucanase
(endo-1,3(4)-) (100 FBG/g, Peelzym.RTM. or Viscozyme.RTM. L,
Novozymes, Inc.), Cellulase (700 EGU/g, Celluclast.RTM., 1.5L, Lot
#CCN03079, Novozymes, Inc.), Protease (2.4 AU-A/g, Alcalase 2.4
LFG.RTM., Lot #PLN05317, Novozymes, Inc.), Alpha-amylase (400
KNU-B/g, Ban 480L.RTM., Lot #ADN04234 or Liquozyme Supra.RTM., Lot
#NBPG002, Novozymes, Inc.), Lipase (100 KLU/g, Greasex 100L.RTM.,
Lot #LAP40013, Novozymes, lnc.), Pectinase (Pectinex 100L
Plus.RTM., Lot #KV5530100, Novozymes, Inc.), Glucoamylase
(Dextrozyme DX.RTM., Lot #NCPP0044, Novozymes, Inc.), and/or
Xyalanase (Shearzyme 500L.RTM., Lot #CDN00243, Novozymes, Inc.) may
be added per 8.times.10.sup.4 gram basis of organic waste.
[0057] If the enzymes are added together to the solid waste phase,
the enzymes may be added as a mixture or cocktail of enzymes or as
a composition comprising multiple enzymatic activities. Such a
mixture or composition may be a commercial product or be prepared
on site. In one embodiment, the mixture of enzymes comprises at
least two enzymes, e.g., three, four, five, six, seven, eight, nine
or ten enzymes, selected from the group consisting of xylanase,
asparaginase, cellulase, hemicellulase, glumayase, beta-glumayase
(endo-1,3(4)-), urease, protease, lipase, amylase, phytase,
phosphatase, aminopeptidase, amylase, carbohydrase,
carboxypeptidase, catalase, chitinase, cutinase, cyclodextrin
glycosyltransferase, deoxyribonuclease, esterase,
alpha-galactosidase, beta-galactosidase, glucoamylase,
alpha-amylase, alpha-glucosidase, beta-glucosidase, haloperoxidase,
invertase, laccase, mannosidase, oxidase, glucose oxidase,
pectinolytic enzyme, pectinesterase, peptidoglutaminase,
peroxidase, polyphenoloxidase, proteolytic enzyme, protease,
ribonuclease and transglutaminase, or combinations thereof.
Examples of mixtures or compositions are described herein.
[0058] In one embodiment of the present invention, the enzymatic
treatment is performed with an enzyme(s) selected from the group
consisting of an enzyme(s) which originates from microbial
fermentation, enzyme(s) derived from a microorganism, such as a
genetic engineered microorganism, or enzyme(s) derived from a
plant, e.g., a genetically engineered plant.
[0059] In accordance with the present invention, the organic waste,
e.g., fresh food waste, to be digested is kept under appropriate
conditions resulting in at least partial release of the nutritional
elements during the enzymatic digestion process. In the present
context, the expression "appropriate conditions" relates to a
specific temperature, time, pH, pressure, and mechanical force in
accordance with the enzyme or enzymes used. The organic waste may
be digested, i.e., bonds are cleaved, without, or with minimized,
decomposition.
[0060] In one embodiment, the process temperature, i.e., the
temperature during the enzymatic digestion, may be between
0.degree. F. and 165.degree. F., such as between 70.degree. F. and
162.degree. F., or 70.degree. F. and 155.degree. F., or 125.degree.
F. and 140.degree. F., or any range in between. In another
embodiment, the temperature during the enzymatic digestion is
132.5.degree. F. The process temperature should be below about
140.degree. F. in order to prevent decomposition of the protein
components within the digested sample. In some embodiments, the
temperature at which the enzymatic digestion step occurs is less
than about 140.degree. F. However, it will be appreciated that the
temperature employed may be within the optimum temperature of the
enzyme(s) used in the process. A skilled artisan will also
appreciate that lower incubation temperatures may be compensated
with longer incubation times or a higher relative concentration of
the enzymatic composition, or both.
[0061] In one embodiment, the process pH, i.e., the pH during the
enzymatic digestion, may be between 0 and 7.0 including any range
in between (e.g., 4.5 to 5.0). A skilled artisan will appreciate
that different enzymes optimally operate within different pH
ranges. In one embodiment, enzymes are selected such that they may
cohabitate and maintain their function in a neutral or acidic
environment. In general, organic waste digested using the processes
described herein have a pH within the range of 4.5 to 5.0. In many
cases, the enzymatic digestion treatment may be carried out with
satisfactory results without any adjustment of the pH before, or
during, the performance of the treatment. However, for some types
of waste materials, it may be advantageous to adjust the pH of the
waste material prior to or during enzymatic digestion. The pH may
be decreased, i.e., acidic conditions or the pH of the reaction
mixture may be increased by adding appropriate amounts of an acid
or base, respectively, and/or a buffer system according to methods
well known in the art. However, it will be appreciated that the pH
employed may be within the optimum pH range of the enzyme(s) used
in the process.
[0062] It has been the inventors' observation that by sustaining a
constant movement of the organic waste, e.g., fresh food waste, the
digestion is improved. Thus, in one embodiment, the enzymatic
digestion step, or during all the steps of the present process, is
under constant agitation, shear, and/or pressure. For example, an
enzymatic digestion apparatus may contain a rotating shaft driven
by a motor to which is fixed two screws oriented in opposite
directions such that mechanical shear forces are exerted against
the digesting organic material within the fixed enclosure.
[0063] The time allotted for the enzymatic digestion in the methods
of the present invention is such that nutrient recovery from the
digested organic waste occurs, e.g., fresh food waste, in a
bioavailable form. The process time is generally between 0 hours
and about 2.5 hours. The batch may be brought uniformally up to a
desired temperature. From that point, it may take between from
about 45 minutes to about 1.5 hours. The time is determined by when
the material has reached its maximum yield. In one embodiment, the
maximum yield occurs at 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%,
81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%,
94%, 95%, 96%, 97%, 98%, 99%, 99.5% or greater hydrolysis (i.e., %
weight of free flowing liquid hydrolysate relative to the total
input weight of the organic material to be digested) or any range
in between. In one embodiment, an enhanced yield occurs when the
batch is >90% hydrolyzed. In another embodiment, the conditions
in which the enzymatic digestion is performed are such that, upon
completion of the reaction, a hydrolysate containing peptides with
an average molecular weight less than 1, 10, 100, 200, 300, 400,
500, 600, 700, 800, 900, 1000 Daltons, such as less than 1, 1.5, 2,
2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, or 10
kiloDaltons.
[0064] After the enzymatic digestion step, the resulting
hydrolysate is filtered in order to remove undigested material
which may be collected and returned to another round of enzymatic
digestion. The separation step may be performed using a number of
methods to separate out undigested material of a given size. In one
embodiment, the hydrolysate is passed through a mesh attached to an
agitator, e.g., a vibratory sieve. The size of the undigested
material that is separated from the hydrolysate is determined by
the size of the openings created by the mesh or sieve. In
representative embodiments, the size of the openings in the mesh or
sieve precludes objects of greater than 10, 20, 30, 40, 50, 60 70,
80, 90, 100, 110, 120, 130, 140, 149, 150, 160, 170, 180, 190, 200,
300, 400, 500, 600, 700, 800, 900 microns or more in diameter, such
as objects greater than 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8,
0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
19, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150,
160, 170, 180, 190, 200, 300, 400, 500 or 1000 millimeters in
diameter or any range in between. In another embodiment, the
hydrolysate may be separated using known methods, such as
centrifugation, filter press, or air classifier methods.
[0065] The hydrolysate in which undigested organic matter of a
specified size has been separated may subsequently be subjected to
a stabilization step. In one embodiment, the hydrolysate is
stabilized with acid (e.g., liquid acid sources including, for
example, hydrochloric, sulfuric, phosphoric, acetic, stearic,
propionic, tartaric, maleic, benzoic, or succinic acids) such that
the hydrolysate has a pH of less than 7.0. In another embodiment,
the acidic pH of the hydrolysate is 3.5. Low pH inhibits microbial
and/or pathogenic activity during storage and transport of the
hydrolysate. An acid source is thoroughly blended in with the
hydrolysate for some amount of time (e.g., for at least 2 hours, 4
hours, 8 hours, 12 hours, 16 hours, 24 hours, or longer) in order
to stabilize the pH.
[0066] The stabilized hydrolysate may be separated in order to
remove undigested material. The separation step may be performed
using a number of methods to separate out undigested material of a
given size. In one embodiment, the hydrolysate is passed through a
mesh attached to an agitator, e.g., a mechanical agitator. The size
of the undigested material that is separated from the hydrolysate
is determined by the size of the openings created by the mesh. In
representative embodiments, the size of the openings in the mesh or
sieve precludes objects of greater than 10, 20, 30, 40, 50, 60 70,
80, 90, 100, 110, 120, 130, 140, 149, 150, 160, 170, 180, 190, 200,
300, 400, 500, 600, 700, 800, 900 microns or more in diameter, such
as objects greater than 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8,
0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
19, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150,
160, 170, 180, 190, 200, 300, 400, 500 or 1000 millimeters in
diameter or any range in between. In one embodiment, the size of
the openings in the mesh precludes objects of greater than 149
microns in diameter, as this ensures that the resulting hydrolysate
will be able to flow unimpeded through hydrolysate applicators,
such as drip irrigation, spray rig, and fertigation equipment
without generating. In another embodiment, the hydrolysate may be
separated using known methods, such as centrifugation, filter
press, or air classifier methods.
[0067] The filtered hydrolysate may be marketed in suitable
containers such as plastic or metal drums or it may be transported
in bulk in tanks. Prior to transport, the filtered hydrolysate may
be checked in a quality control step including, for example,
analyses of pH and gas levels. The filtered hydrolysate may also be
used in a variety of manners, including, for example, as
nutraceuticals, organic fertilizers, pharmaceuticals, aquaculture
feeds, animal feeds, and biostimulants. In one embodiment,
additives may be added to alter the qualities of the filtered
hydrolysate (e.g., addition of kelp, molasses, and humic acids). In
other embodiments, the hydrolysate may be concentrated such that
the hydrolysate has a dry solid residue cocnentration of at least
5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%,
70%, 75%, 80%, 85%, 90%, 95%, 99%, or greater or any range in
between. For example, the concentration may be performed in a
system for continuous concentration under vacuum, the degree of
concentration being monitored by a mass measuerer. Alternatively,
the hydrolysate may be concentrated to dryness, for example, by
spray-drying, thus producing a final product in powder form.
[0068] The separated hydrolysate resulting from the enzymatic
digestion process described herein, alone or further processed
according to the optional steps described herein, allows for the
recovery of nutrients from digested organic waste, e.g., fresh food
waste, in a bioavailable form. Such processing conditions the
nutrients for relatively rapid uptake by soil microorganisms and
plants, as contrasted with the more extended period required for
bio-degrading the cellular components of manures and organic wastes
incorporated into soils as fertilizers. Such processing also
conditions the nutrients for rapid metabolization when the filtered
hydrolysate is used as an aquaculture or animal feed.
[0069] In one embodiment, the process described herein may be
adapted and coupled with a process for producing biofuels, such as
biogas or alcohols. The concentrated nutrient availability in a
bioavailable form represents an enhanced feedstock for biogas
producing microorganisms. The hydrolysate may thus be used by one
or more microorganisms to produce fermentation products such as
ethanol. Any microorganism capable of converting a carbon source
(e.g., glucose) to a biofuel (e.g., ethanol) may be used in the
process according to the invention. For example, a suitable
microorganism may be a mesophilic microorganism (i.e. one which
grows optimally at a temperature in the range of 20-40.degree. C.),
e.g. a yeast also referred to as "baker's yeast", Saccharomyces
cerevisiae.
[0070] It will be understood, that a useful ethanol-fermenting
organism may be selected from a genetically modified organism of
one of the above useful organisms having, relative to the organism
from which it is derived, an increased or improved useful chemical
forming activity (e.g., biofuel-fermenting activity).
[0071] An anaerobic or aerobic fermentation may employ one or more
fermenting microorganisms capable of degrading or converting
substances present in the organic waste to form, e.g., combustible
fuel, such as methane. In one embodiment of the present invention,
an initial treatment of the waste is performed using
methane-producing microorganisms (also known as methanogens), which
constitute a group of prokaryotes that are capable of forming
methane from certain classes of organic substrates, methyl
substrates or acetate under anaerobic conditions. It will be
appreciated that useful methanogenic bacteria may be selected from
a genetically modified bacterium of known methanogenic bacteria,
having, relative to the organism from which it is derived, an
increased or improved methane producing activity. Other useful
microorganisms which could be used in an anaerobic fermentation of
the waste include certain fermentative anaerobic bacteria capable
of converting, for example, glucose to products such as acetate,
propionate, butyrate, hydrogen and CO.sub.2, and so-called
acetogenic bacteria, which convert organic substances such as
propionate, butyrate and ethanol to acetate, formate, hydrogen and
CO.sub.2.
[0072] The process according to the invention is in particular
suitable for applications coherent with large-scale waste
management systems. When the process is performed for downstream
biogas production, excess heat from the biogas production plant may
be utilized as process energy in the incubation processes.
[0073] In a further aspect, the present invention provides the
nutritional element obtained in the process (e.g. hydrolysate)
according to the invention for use as nutraceuticals, organic
fertilizers, pharmaceuticals, aquaculture feeds, animal feeds, and
biostimulants.
[0074] In yet another aspect, the present invention provides an
enzyme mixture comprising at least two enzymes, e.g., three, four,
five, six, seven, eight, nine or ten enzymes, selected from the
group consisting of xylanase, asparaginase, cellulase,
hemicellulase, glumayase, beta-glumayase (endo-1,3(4)-), urease,
protease, lipase, amylase, phytase, phosphatase, aminopeptidase,
amylase, carbohydrase, carboxypeptidase, catalase, chitinase,
cutinase, cyclodextrin glycosyltransferase, deoxyribonuclease,
esterase, alpha-galactosidase, beta-galactosidase, glucoamylase,
alpha-amylase, alpha-glucosidase, beta-glucosidase, haloperoxidase,
invertase, laccase, mannosidase, oxidase, pectinolytic enzyme,
peptidoglutaminase, peroxidase, polyphenoloxidase, proteolytic
enzyme, protease, ribonuclease and transglutaminase, or
combinations thereof.
[0075] In a still further aspect, the invention relates to the use
of the enzyme mixture according to the invention for releasing
nutritional elements from waste.
[0076] This invention is further illustrated by the following
examples which should not be construed as limiting. The contents of
all references, patents and published patent applications cited
throughout this application are incorporated herein by
reference.
EXAMPLES
Example 1
[0077] The following example describes an exemplary process for
releasing nutritional elements in a bioavailable form from
enzymatic digestion of fresh organic waste. Fresh organic waste is
obtained and handled so as to minimize biological degradation,
which includes the steps of frequent waste pickup(e.g., before 36
hours after discarding as elapsed), materials are kept refrigerated
at all times, training personnel on source separation and being
able to identify decomposition and proper use of the specialized
containers, and specialized waste containers specifically designed
for each waste stream. The fresh food waste is ground to particles
less than 1/2 inch in length. An enzyme cocktail comprising 1 gram
(i.e., the weight of 50 mL of enzyme given that the density of the
enzymes solutions is similar to that of water) of each enzyme
(e.g., 1 g of Asparaginase (3,500 ASNU/g, Acrylaway.RTM. L,
Novozymes, Inc.), 1 g of Beta-glucanase (endo-1,3(4)-) (100 FBG/g,
Peelzym.RTM. or Viscozyme.RTM. L, Novozymes, Inc.), 1 g of
Cellulase (700 EGU/g, Celluclast.RTM., 1.5L, Lot #CCN03079,
Novozymes, Inc.), 1 g of Protease (2.4 AU-A/g, Alcalase 2.4
LFG.RTM., Lot #PLN05317, Novozymes, Inc.), 1 g of Alpha-amylase
(400 KNU-B/g, Ban 480L.RTM., Lot #ADN04234, Novozymes, Inc.), and 1
g of Lipase (100 KLU/g, Greasex 100L.RTM., Lot #LAP40013,
Novozymes, Inc.) is added per 8.times.10.sup.4 gram of organic
waste to be enzymatically digested. The mixture is then added to a
digestion tank an allowed to incubate for up to 2.5 hours,
generally between 45 minutes and 1.5 hours, and at a temperature of
between 125.degree. F. and 140.degree. F. under constant stirring
and atmospheric pressure. The mixture is incubated such that a
resulting liquid hydrolysate is typically greater than 90% or 95%
or more by weight relative to the weight of the initial organic
waste loaded. The hydrolysate is generally filtered from coarse
materials greater than 1/16.sup.th in. in diameter by mechanical
agitation and separation through a mesh. The coarse-filtered
hydrolysate is subsequently pumped to intermediate storage tanks
and mixed with acid in the ratio of 20 liters acid to 1000 liters
of hydrolysate for 4 hours or longer until the pH is less than 7.0
(e.g., until the pH is 3.5). After acid stabilization, the liquid
hydrolysate is fine-filtered by mechanical agitation and separation
through a mesh comprising pores of 100 US Sieve Mesh, which
excludes particles larger than 149 microns. Excluded material
resulting from either of the filtration steps may be re-digested,
composted, or used as a substrate for anaerobic digestion. The
fine-filtered hydrolysate is pumped into storage tanks until ready
for dispensation into smaller volumes for transport and sale.
Example 2
[0078] The following example demonstrates that nutritional elements
are released in a bioavailable form upon execution of the processes
as described herein. Unground material, using only alcalaise
enzymes produces a 66% yield of hydrolysate. The same yield was
achieved when processed at 125.degree. F., 13.degree. F.,
14.degree. F., and 160.degree. F. Each temperature range was
checked at 30 minutes intervals to determine what percentage of
hydrolysate was being achieved. Each digest was allowed to run for
31/2 hours before the experiment was stopped. Each test produced a
yield of 66% +/-2%.
[0079] The same tests were run as above with unground material and
using alcalaise and nature pepsim from squalus amaythias. Yields
from each test improved slightly to 71% +/-2%. Unground material
was subsequently processed at the same temperature and time ranges
as above using the 6 enzymes (main enzymes) from Lew's selection as
well as natural pepsim from squalus amaythias and resulted in a
maximum yield of 78% at 145.degree. F. for 2.5 hours. Finally,
material ground to less than 3/8'' in diameter, when processed
using the using the same enzyme set as the previous test, as well
as the same time and temperature range, produced a yield of
95%.
INCORPORATION BY REFERENCE
[0080] All publications, patents, and patent applications mentioned
herein are hereby incorporated by reference in their entirety as if
each individual publication, patent or patent application was
specifically and individually indicated to be incorporated by
reference. In case of conflict, the present application, including
any definitions herein, will control.
Equivalents
[0081] Those skilled in the art will recognize, or be able to
ascertain using no more than routine experimentation, many
equivalents to the specific embodiments of the invention described
herein. Such equivalents are intended to be encompassed by the
following claims.
* * * * *