U.S. patent number RE30,086 [Application Number 05/944,048] was granted by the patent office on 1979-08-28 for plastic emulsion food spread.
This patent grant is currently assigned to Lever Brothers Company. Invention is credited to Norman J. Carlile, Theodorus J. Van Selm.
United States Patent |
RE30,086 |
Carlile , et al. |
August 28, 1979 |
Plastic emulsion food spread
Abstract
Margarine and low fat emulsion food spreads have been prepared,
the fat phase of which consists essentially of randomized palm oil.
The randomization is usually carried out on palm oil alone and
enables a substantial amount of palm oil to be incorporated into
the fat phase without the onset of excessive post-hardening
effects. The randomization also minimizes the amount of expensive
vegetable oils such as sunflower oil which have hitherto been found
necessary adjuncts with palm oil in such products, particularly in
recently-developed soft spreads which can be spread directly at
domestic refrigerator temperatures. The major part of the spreads
of the invention preferably consist of a fat of melting point
25.degree.-30.degree. C., particularly derived from vegetable
oils.
Inventors: |
Carlile; Norman J. (Wirral,
GB), Van Selm; Theodorus J. (Krimpen aan den Ijssel,
NL) |
Assignee: |
Lever Brothers Company (New
York, NY)
|
Family
ID: |
27258039 |
Appl.
No.: |
05/944,048 |
Filed: |
September 18, 1978 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
357750 |
May 7, 1973 |
03939282 |
Feb 17, 1976 |
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Foreign Application Priority Data
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May 10, 1972 [GB] |
|
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21794/72 |
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Current U.S.
Class: |
426/603;
426/607 |
Current CPC
Class: |
A23D
7/001 (20130101) |
Current International
Class: |
A23D
7/00 (20060101); A23D 003/00 () |
Field of
Search: |
;426/602,603,604,607 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hart; Charles N.
Assistant Examiner: Therkorn; Ernest G.
Attorney, Agent or Firm: Farrell; James J. Kurtz; Melvin H.
Schultz; Ira J.
Claims
What is claimed is:
1. A plastic emulsion food spread comprising an aqueous phase and a
fat phase in the form of an emulsion in which the fat phase is
partly crystallized and comprises by weight of the fat phase, from
about 5% to about 40% of a triglyceride composition, the fatty acid
residues of which are in random distribution and consist
essentially of the acid residues of palm oil, and a major
proportion of an additional fat where said fat is selected from the
group consisting of corn, cottonseed, groundnut, safflower,
sunflower, sesame and soybean oils.
2. A food spread according to claim 1 which contains from about 15
to about 30 wt % palm oil, based on total fat phase.
3. A food spread according to claim 1 wherein said spread is in
soft tub form, having a penetration range from C.sub.5 less than
900 grams cm.sup.2 to C.sub.20 between 50 and 150 grams
cm.sup.2.
4. A food spread according to claim 1 wherein said spread comprises
a low fat spread containing by weight of the spread a major
proportion of aqueous phase dispersed in a minor proportion of fat
phase.
5. A method of preparing a water-in-oil emulsion food spread having
an enhanced palm oil content, comprising dispersing an aqueous
phase in a fat phase to form an emulsion and chilling, working and
resting the emulsion to crystallize at least part of the fat phase,
wherein the fat phase is prepared by randomizing palm oil and
blending, by weight of said fat phase, from about 5 to about 40% of
said palm oil with a major proportion of an additional vegetable
oil selected from the group consisting of corn, cottonseed,
groundnut, safflower, sunflower, sesame and soybean oils.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to margarines and like edible emulsion food
spreads of which the fat phase contains palm oil. It is
particularly concerned with spreads which are soft enough to be
spread at domestic refrigerator temperatures, including those which
on account of their low fat contant are in demand in low calory
diets. The more stable of these, like margarine, are of the
water-in-oil variety and are similarly prepared, by chilling,
working and resting the previously prepared emulsion, which may
contain additional flavouring, colouring, vitamin and emulsifier
components similar to those found in conventional margarine. These
combined operations are nowadays carried out in a continuous
fashion, in scraped surface heat exchangers of the Votator type and
partially crystallise the fat to form a network in which the
globules of the aqueous phase are retained, thus stabilising the
emulsion against undesirable accretion of the droplets with
consequent emulsion breakdown and multiplication of bacterial
growth.
Both the oral response developed upon eating margarine and similar
fat spread products and the textural response experienced upon
spreading them are largely determined by the composition of the fat
phase of the product. Great skill, much of it of an empirical
nature, is needed to devise the most appropriate fat composition,
often a blend of many fats, to meet these needs with economic
benefit. In recent times an even more stringent requirement needs
to be met for so-called soft margarines and similar spreads which
can be spread directly from storage in domestic refrigerators, ie
about 5.degree. C. This requirement calls for a particularly flat
hardness/temperature response and is a most exacting one to
meet.
2. The Prior Art
Palm oil is a cheap and abundant vegetable oil already in
widespread use in the Margarine Industry. The limitations imposed
upon the amount of palm oil that can be included in margarine and
like fat spreads relate to its tendency to confer on fat
compositions in which it is incorporated, its own slow
crystallising characteristics. This leads to the phenomenon of
post-hardening in which a product that is satisfactory in its
textural characteristics when it is initially prepared,
subsequently hardens on storage to affect both its oral response
when it is said to be grainy, and its ability to spread at ambient
or lower temperatures.
Interesterification as a technique for modifying the
characteristics of palm oil and to admit of its greater use in the
Industry is described in "Margarine" 2nd Edition, Andersen and
Williams, 1954 page 3/8-1/3 and the general description of the
technique is given on pages 54 etc. In this and in other
publications however the palm oil is corandomised with a comparable
amount of a second oil, either a lauric oil, vide British Pat. No.
874,675, a C.sub.16 -C.sub.18 vegetable oil in a fat formulation
that includes a substantial trans-acid content combined in the
triglycerides of the fat composition.
In other references, eg Seiden U.S. Pat. No. 3,353,964, similarly a
corandomised blend is disclosed, but between lauric fats and fats
of long-chain acids, ie C.sub.20 -C.sub.22.
Melnick U.S. Pat. No. 2,921,855 describes a corandomised blend,
used as a margarine fat, of a triglyceride oil rich in combined
polyunsaturated fatty acid, with a highly hydrogenated fat, while
Nelson U.S. Pat. No. 2,855,311 discloses the corandomisation of a
blend of palm oil with a variety of liquid oils.
In none of these prior disclosures does any suggestion appear that
a remedy to overcome the now widely-recognised problem of using
palm oil in substantial quantities in emulsion spreads may lie in
randomisation essentially of the oil itself, without recourse to
the profound changes brought about in modifying the properties of
this oil by distributing its own fatty acid moieties among those of
other, distinctly different fats.
This invention relates to edible fat compositions such as
margarines and shortenings in the preparation of which palm oil is
used.
Palm oil is readly available and low in cost among vegetable oils
and in several respects appears suitable for the preparation of
edible fat products such as margarines and shortenings. Its
widespread adoption for these purposes has however been handicapped
in the past by its slow rate of crystallisation, with the result
that, long after processing has been completed products containing
palm oil undergo hardening and suffer other undesirable changes
caused by the continued crystallisation of the oil.
It has now been found that margarine products containing
substantial quantities of palm oil may be prepared by randomising
the palm oil and preparing a fat blend therewith.
Preferably the palm oil is randomised alone, but it may be
corandomised with small amounts, not exceeding 10 weight % and
preferably less than 5 wt %, of other edible oils or fats, whether
of vegetable or animal origin, including marine oil. Similarly,
although the palm oil may be modified somewhat by fractionation or
other treatment before being randomised, this should essentially
impose no major modification upon the inherent characteristics of
the fat.
It is indeed an important feature of the invention that the fatty
acid composition of the oil remains unchanged, in contrast to the
effect of using fractionation methods. Similarly, the glyceride
composition of other fats present in the products of the invention
remain unchanged, in contrast to corandomisation methods which
change the glyceride composition of both the palm and the other
corandomised fats. For example, the glyceride components of palm
oil may be separated into a high melting stearine fraction and a
low melting oleine fraction by subjecting palm oil to fractional
crystallisation, the compositions of the fractions differing
markedly, to an extent depending upon the conditions of the
crystallisation. In accordance with U.S. Pat. No. 3,189,465 an
oleine fraction obtained in this way is blended with other fats in
margarine formulations. Again, stearine and oleine fractions may be
obtained by subjecting palm oil to directed interesterification,
carried out under conditions favouring the continued formation of a
limited range of glycerides, usually a stearine fraction separated
from the liquid phase by carrying out the process at comparatively
low temperatures. The stearine and oleine fractions obtained in
this way, while again differing markedly from one another, are
composed essentially of different combinations of the fatty acids
of the oil and thus contain different glycerides from those
originally present. The stearine fraction obtained in this way has
been proposed for use in shortening compositions.
In both fractionation and directed interesterification methods a
substantial proportion of the palm oil is described. The
disadvantages described may also be overcome, while utilising whole
palm oil, by subjecting it to hydrogenation, but the resultant
change in glyceride composition that this brings about leads to
unsatisfactory melting characteristics in margarine and similar
food spreads by producing a cloying sensation in the mouth due to
the presence of higher melting glycerides.
A further advantage of the invention is that no other fat need by
involved in the interesterification. This again provides
substantial economies and permits the use, in blends with the
randomised palm oil, of other fats in proportions providing optimum
melting characteristics whose own melting characteristics are
unmodified by corandomisation with the palm oil. The cool-melting
characteristics of lauric fats for example, which may be present in
the products of the invention are accordingly retained, since they
are blended instead of being corandomised with palm oil in
accordance with earlier proposals.
The invention is particularly useful in the preparation of
margarine and like emulsion fat spreads, which are often required
to meet rigid product specifications, especially as to their
melting and hardness characteristics. In particular, the so-called
soft margarines now in vogue are required to remain easily
spreadable, as table margarines, at domestic refrigerator
temperatures, ie about 5.degree. C., while yet being of plastic
consistency at ambient temperatures, which may be as high as
20.degree. C. These requirements imply a flat response to
temperature of hardness value. If this is measured in accordance
with the penetration method of Haighton, then a soft margarine may
be described as one having the penetration range from C.sub.4 less
than 900 g/cm.sup.2 and particularly less than 750 g/cm.sup.2, to
C.sub.20 between 50 and 150 g/cm.sup.2 according to the time of
year. A very small amount of whole or modified palm oil is
permissible in soft spreads, at most about 10 wt % beyond which the
product tends to unacceptable hardness.
The invention is particularly suitable for the preparation of fat
blends for soft margarines, meeting the above requirements for
hardness values with as much as 40 wt %, in contrast to
conventional formulations in which not more than 25 wt % is
practical in spread formulations, many of which nevertheless fail
to meet the above-stated requirements for soft spreads, unless a
substantial quantity, often as much as 40 wt % or even more, of an
expensive liquid vegetable oil, for example sunflower oil, is also
present. A particular advantage in the invention is that not only
is less oil of this kind necessary, but it may be totally replaced
by cheaper oils, for example soybean oil. Preferably the fat
compositions of the invention contain from 15 to 300 wt % palm oil,
preferably about 20-25 wt %. The dilatation values of palm oil
increase with randomisation, and amounts in excess of 40 wt % are
therefore less desirable.
In additon to meeting the above penetration characteristics, the
fat component of soft spreads is also required, for good consumer
response to fulfill palatability requirements provided by melting
characteristics thay may be expressed by dilatation values measured
in the manner described in J. Am. Oil Chem. Soc. (1954) 31, pp.
98-103. These should lie between about D.sub.5 =600 and D.sub.35
below 50. These requirements are met largely by an appropriate
choice of fats or oils with which the randomised palm is blended,
and hardness also by adjustment of the conditions under which the
fat emulsion is processed. In accordance with contemporary
practice, the spreads of the present invention are preferably
prepared from an emulsion of an aqueous phase in the fat phase,
followed by chilling and working the composition to crystallise the
fat, in "Votator" equipment including a scraped surface heat
exchange chiller. Other things being equal, greater amounts of palm
oil may be incorporated using longer residence times in the
Votator.
In addition to palm oil, the fat blends of the invention may
include a variety of other components. A proportion of unrandomised
palm oil may for example be present, but this should desirably not
exceed 10%, since it induces post-processing hardening during the
shelf-life of the spread, particularly within a few hours of
manufacture. Similarly the presence of unrandomised hardened palm
or palm fraction should not exceed 10 wt %.
Other semi-solid fats of the palmitic variety, eg cottonseed oil,
may be included in similar quantities and lauric fats, eg palm
kernel oil, babassu and coconut oils and their fractions, are all
suitable components. Several animal fats rich in palmitic acid are
also suitable, eg lard and tallow; others include marine oils, for
example herring and sardine oils, although these in 10% with
general practice may require hardening treatment by hydrogenation
to confer flavour stability. Again, however, preferably not more
than 10% and particularly not more than 5% by weight of these fats
should be present in the fat composition.
The major part, ie more than 50 wt % of the fat component of the
spreads according to the invention is composed of vegetable oils
which at ambient temperatures, ie 15.degree. C. are liquid, or
which are lightly hydrogenated to a melting point of
15.degree.-30.degree. C. These comprise for example corn,
groundnut, safflower, sunflower, sesame and soybean oil. The latter
in particular, being cheap is preferred. In keeping with widespread
practice, it is preferably hydrogenated at least in part to
stabilise the oil against deterioration, although the oil may
remain largely unsaturated with an Iodine Value of 90 or more.
Besides meeting the requirement for producing soft, palatable
spreads, the choice as well as the amount of liquid oil is
preferably governed by the widely accepted desirability of
incorporating within the composition glycerides of the
polyunsaturated, so-called essential acids. Preferably the fat
compositions of the invention consist of randomised palm oil and a
fat or fat blend having a melting point of 25.degree.-30.degree. C.
In this specification the melting point of a fat means the
temperature at which the fat becomes wholly melted, shown by slowly
heating the fat until it turns clear.
It will be understood that the inveniton may be applied in the
preparation of margarine and of other spreads having a lower fat
content than is required in margarine. These so-called low fat
spreads may contain as little as 40 wt % fat. The invention is also
applicable to shortening compositions in which whole randomised
palm oil is blended.
EXAMPLE 1
A margarine fat was prepared by blending various components in the
following amounts of weight:
______________________________________ Soybean Oil 18 Hardened
Soybean Oil 57 (53% slip m.pt. 28.degree. C. I.V.-105) ( 4% slip
m.pt. 36.degree. C. I.V.- 50) Interesterified Palm Oil 21 Hardened
Palm Oil 4 (Slip m.pt. 45.degree. C. I.V.-45)
______________________________________
A margarine emulsion was prepared by agitating the fat at
40.degree. C. in a mixture with 16% of an aqueous phase comprising
tap water and 0.5 wt % of lecithin and 0.1 wt % based on the fat in
the fat phase of a partial glyceride emulsifier and flavouring
agents, vitamins, colouring matter and salt in customary
amounts.
The water-in-oil emulsion formed was supplied continuously at about
80 kg/hr to the first of series of three scraped surface chillers,
each 5 cm in diameter, 25.5 cms in length and having a chilling
surface of 0.04 m.sup.2. Between the first or second pair a
pre-crystalliser was interposed, comprising a vessel 3 liters in
capacity and also equipped with a close-fitting agitator but with
no chilling capacity. No material difference was observed between
the two pre-crystallizer positions. A post-crystalliser of similar
construction to the pre-crystalliser but half the size, followed
the third chiller unit. The equipment substantially reproduced on a
smaller scale the effect and operation of a full-size margarine
plant. Residence time in the crystallisers was 3 minutes.
The chilled emulsion emerged from the first chiller at about
17.5.degree. C. and gained about 1.degree. C. in the
pre-crystalliser, emerging at 16.degree. C. and 14.degree. C. from
the second and third chiller units and finally at
18.degree.-20.degree. C. from the post-crystalliser, from which it
was pour-filled into standard 250 gm tubs.
After storage for 3 days at 15.degree. C. and a day at the test
temperatures the product was tested for hardness. Dilatation values
of the fat were also obtained. The results of the tests are given
in Table I.
TABLE I ______________________________________ Hardness Temp.
.degree. C. (C values) Dilatation
______________________________________ 5 655 (617) 475 10 332 (344)
425 15 106 (125) 340 20 132 (144) 250 35 -- 50 40 -- 10
______________________________________
The product was of pleasing texture at temperatures from 5.degree.
to 20.degree. C., in which range it remained plastic and could be
readily spread. It melted quickly and readily on the tongue. The
melting point of the fat was 33.3.degree. C.
The experiment was repeated at twice throughput (11/2 minutes'
residence time) while maintaining the same temperature profile and
agitator speed. The corresponding characteristics of the product
are given in Table I in brackets.
A series of three comparative trials was carried out based on fat
compositions containing the same ingredients, except for the
substitution of the randomised palm oil by unrandomised palm oils
in the amounts 15, 21 and 25 wt %, the amounts of the remaining
ingredients being adjusted as little as possible, to obtain similar
dilatation values at 5.degree., 10.degree., 15.degree., 20.degree.,
25.degree. and 30.degree. C. These varied less than 10% of the
arithmetic mean of the four compositions and at 35.degree. C. the
values were 35, 35 25 and 55. Nevertheless, the hardened palm and
soybean oil content remained unchanged and the amount of soybean
oil was changed only comparatively slightly.
The melting points of the comparative fat compositions varied from
31.5.degree. to 33.5.degree. C. None of the margarine products from
these trials however, although prepared under the same conditions
as before, showed in hardness tests a C.sub.5 value less than 700
and a C.sub.20 value within the range 50-150, nor could these be
obtained by adjustments to the equipment in which the emulsions
were worked. In only one example was the C.sub.5 value less than
900 and most were well above 1,000. Similarly, the majority of the
C.sub.20 values were above 150.
EXAMPLE 2
A low fat table spread was prepared from an emulsion consisting of
40 wt % fat phase in which 60 wt % aqueous phase was dispersed,
conventional margarine additives including colouring matter and
emulsifiers being included. The emulsifier was chilled, worked and
rested in a series of Votator A and B units including a
precrystalliser unit in which a portion of the processed emulsion
containing crystallised fat was recirculated to mix with a fresh
emulsion.
The fat phase contained by weight the equal parts of refined
randomised palm oil and soybean oil, and half as much coconut oil.
In different products 25% or 50% of the soybean oil was first
selectively hardened to a fall of about 25 Iodine Value units to
improve flavour stability.
Samples of all the products exhibited satisfactory hardness and
dilation characteristics, after storage for several weeks at
10.degree. and 20.degree. C., for a soft spread, ie hardness at
5.degree. and 20.degree. C. below 900 and 50-100 and dilatations at
5.degree. and 35.degree. C. about 600 and below 50.
A comparable product with corresponding characteristics was made
using a fat phase almost 1/3 of which consisted of palm kernel oil
and more than 40% of sunflower oil. It contained in addition only
10% soybean oil. Not more than 15% non-randomised palm oil could be
included, part of which was selectively hardened to give better
dilatation characteristics.
* * * * *