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Patent 1057571 Summary

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(12) Patent: (11) CA 1057571
(21) Application Number: 1057571
(54) English Title: LOW FAT SPREAD
(54) French Title: ANALOGUE DE LA MARGARINE PAUVRE EN MATIERES GRASSES
Status: Term Expired - Post Grant Beyond Limit
Bibliographic Data
Abstracts

English Abstract


Abstract of the disclosure
The invention provides water-in-oil type low-fat
spreads of excellent organoleptic properties, acceptable
microbiological stability, and a good emulsion stability
even under refrigerator conditions.
The low-fat spread, which has a pH value of less than
6, comprises 38-50% of plastic fat, preferably butterfat,
0.1-1.5% of partial glycerides, preferably substantially
completely saturated monoglycerides, and an aqueous phase
containing 1-23% of edible soluble milk proteins and high-
molecular non-dairy substances e.g. hydrocolloids, the
weight ratio of milk proteins to non-dairy substances being
15:1 to 1:5, preferably 8:1 to 1:3.


Claims

Note: Claims are shown in the official language in which they were submitted.


THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. Low-fat spread of the water-in-oil type comprising 38 to
50% of plastic fat, 0.1 to 1.5% of partial glycerides, and the
balance of an aqueous phase of a pH value of less than 6, the
aqueous phase containing 1 to 23% of edible, soluble milk
proteins and edible non-dairy high-molecular substances of a
molecular weight of 104 - 106, selected from the group consisting
of non-dairy animal and vegetable proteins and carbohydrates
and derivatives of said proteins and carbohydrates, the weight
ratio of soluble milk proteins to non-dairy high-molecular
substances being from 15:1 to 1:5.
2. Low-fat spread of the water-in-oil type comprising 38 to
50% of plastic fat including butterfat, 0.1 to 1.5% of partial
glycerides and the balance of an aqueous phase of a pH value of
4.5 to 5.8, said aqueous phase containing edible soluble milk
proteins and edible non-dairy high-molecular substances of a
molecular weight of 104 - 106, selected from the group consisting
of vegetable proteins, single cell proteins, gelatine, poly-
saccharides, including their alkylated derivatives, starch,
cellulose, CMC, vegetable gums and their corresponding salts,
the weight ratio of soluble milk proteins to non-dairy high-
molecular substances being from 8:1 to 1:3.
3. Low-fat spread according to claim 1 in which the fat content
is from 39 to 45%.
4. Low-fat spread according to claim 3 in which the fat
contains a mixture of butterfat and vegetable fat of a poly-
unsaturated fatty acid content of 40% or more.
5. Low-fat spread according to claim 1 in which the weight
ratio of soluble milk proteins to non-dairy high-molecular
substances is from 5:1 to 1:1.5.
6. Low-fat spread according to claim 1 in which the pH value

is from 4.8 to 5.2.
7. Low-fat spread according to claim 1 in which the total
content of edible soluble milk proteins and non-dairy high-
molecular substances is from 2 to 16% of the aqueous phase.
8. Low-fat spread according to claim 1 in which the non-dairy
high-molecular substances are hydrocolloids.
9. Low-fat spread according to claim 8 in which the hydro-
colloid content is from 0.2 to 3% of the aqueous phase.
10. Low-fat spread according to claim 1 in which the content
of soluble milk proteins is 1.0 to 6.0% of the aqueous phase
11. Low-fat spread according to claim 1 in which the lactose
content is no more than 4% of the aqueous phase.
12. Low-fat spread according to claim 1 in which the partial
glycerides are substantially completely saturated monoglycerides.
16

Description

Note: Descriptions are shown in the official language in which they were submitted.


lOS757~
The invention relates to water-in-oil type low-fat
spreads and to processes for their preparation.
Particularly the invention relates to butterfat-
containing low-fat spreads or low-fat spreads containing fat
blends, e.g. margarine fats, or blends of butterfat and
vegetable fat.
The low-fat spread of the present invention comprises
38 to 50~ of plastic fat, 0.1 to 1.5~ of partial glycerides,
and the balance of an aqueous phase of pH value of less than 6,
the aqueous phase containing 1 to 23% of edible, soluble milk
proteins and edible non-diary high~molecular substances, the
weight ratio of soluble milk proteins to non-dairy high-
molecular substances being from 15: 1 to 1:5.
A great advantage of the present invention is that it
can provide water-in-oil type low-fat spreads which remain
stable even at refrigerator temperature, e.g. about 4-8C, and
which have an excellent taste, closely resembling that of
butter, and which from a microbiological point of view have
acceptable keeping qualities.
Proteinaceous water-in-oil type low-fat spreads have
been disclosed e.g. in German Patent Application No. 1,200,113;
such products, however, require a very specific proteinaceous
aqueous phase with a pH value of 5-6; besides, they do not
contain non-dairy high-molecular substances and do not always
sufficiently match the desired butter-like taste. It should
be realized that proteins when merely added to an acidified
aqueous phase will increase the pH value to a level that, from
the point of view of microbiological keeping qualities, is
unacceptable; this also applies to the proteinaceous water-
in-oil type low-fat spreads disclosed e.g. in U.S. Patent
Specification No. 3,366,492. Since, moreover, in the products
disclosed in the last-mentioned specification no partial
glycerides are present, the physical stability of the wat~r-
D

lOS7S7~
in-oil emulsion, particularly at relatively low temperatures,
is not sufficiently guaranteed.
In this specification by "soluble milk proteins" are
understood proteins, particularly unmodified proteins, which
are for at least 80~ soluble when dispersed in water at ambient
temperature (20C) in a proportion of 1 gram per litre; such
proteins are e~g. native milk proteins and those milk proteins
that have been obtained by ultra-filtration, gel filtration
or dialysis of milk products, e.g. whole milk, skim milk,
buttermilk, whey etc.
By "edible non-dairy high-molecular substances" are
understood soluble or water-dispersible (for at least 80~ at
20C) non-dairy animal and vegetable proteins and/or carbo-
hydrates and derivatives of said proteins and carbohydrates,
of a molecular weight of 104 or more, e.g. 104- 106.
Suitable examples thereof are e.g. vegetable proteins,
e.g. soya and rapeseed proteins, single cell proteins, gelatine,
polysaccharides including their alkylated derivatives, starch,
cellulose, CMC and vegetable gums, e.g. carrageenan, pectin,
alginates, guar gum, agar-agar, locust bean gum and/or their
corresponding salts.
Preferably the fat content of the low-fat spread of the
invention is from 39 to 45 per cent of the emulsion. Suitably
the fat comprises butterfat and the emulsion can be prepared by
blending butter with a suitable additional aqueous phase under
conditions that favour the formation of a water-in-oil type
emulsion. The emulsion can also be prepared by phase inversion
of an oil-in-water emulsion in a manner known per se.
Advantageously the fat phase of the low-fat spread accord-
ing to the invention contains a mixture of butterfat andvegetable fat, e.g. fat of a polyunsaturated fatty acid content
of 40% or more, for instance sunflower oil, safflower oil, corn
oil, wheat germ oil, soyabean oil etc.
--3--

S7~
Preferably the low-fat spread contains soluble milk proteins
and non-dairy high-molecular substances in a weight ratio of
8:1 to 1:3, particularly 5:1 to 1:1.5, especially about 2:1, at
a protein content of about 0.5 to 0.9~ (calculated on the weight
of the low fat spread). At a weight ratio of soluble milk
proteins to non-dairy high-molecular substances of 5:1 to 1:1.5,
the protein content in the aqueous phase can vary from about
0.4% (ratio 1:1.5; total content milk protein and non-dairy
high-molecular substances 1%) via 0.8% (ratio 5:1; same total
content of milk protein and non-dairy ingredients) and 9% (weight
ratio 1:1.5; total content high-molecular substances and
soluble milk protein 23%) up to about 19% (weight ratio 5:1;
total content ingredients in aqueous phase 23%).
The aqueous phase of the emulsion of the invention should
be acid, mainly for microbiological reasons, i.e. having a pH
value of less than 6.0, preferably 4.5 to 5.8, especially 4.8
to 5.2. The lower the pH value, the better the product is
resistant to storage in open or not sufficiently air-tight
containers; too low a pH value, i.e. below 4.5, should however,
be avoided for organoleptical reasons.
On physiological grounds, for organoleptical reasons, and
in some countries even prescribed by law, low-fat spreads,
particularly butter-based low-fat spreads, should contain
proteins. Since in fact proteins favour the formation of oil-
in-water emulsions, often coagulate at acid pH, and can give
rise to microbiological instability, they present a serious
problem.
Preferably the total content of edible soluble milk
proteins and non-dairy high-molecular substances is from 2 to
16% by weight of the aqueous phase, particularly 3.5 to 15% by
weight of the aqueous phase.
Preferably non-dairy high-molecular substances comprise
hydrocolloids, e.g. in a concentration of from 0.2 to 3~ by

57571
weight of the aqueous phase, preferably 0.5 - 1.5%, particularly
0.6 to 1.0%. Most suitable are hydrocolloids that interact
with the proteins and increase the solubility of the aqueous
phase.
It has further been observed that various hydrocolloids
can keep the proteins sufficiently soluble even if the product
is subjected to a heat treatment, e.g. a pasteurizing treatment.
Mixtures of two or more hydrocolloids are particularly
preferred, since the presence of such a mixture has often
proved to be more effective than the presence of one single
hydrocolloid.
Suitable hydrocolloid mixtures comprise e.g. (10% - 90%):
(90% - 10%) mixtures of pectin and one or more hydrocolloids
of natural origin, e.g. carageenan, agar-agar, guar gums, locust
bean gum, etc., and/or their corresponding salts. Mixtures of
pectin and carageenan are particulary preferred, since these
hydrocolloid mixtures have shown to be particularly effective
in stabilizing the low-fat spreads of the invention.
As previously shown, the content of soluble milk proteins
can vary within relatively wide limits.
The best products however generally have a soluble milk
protein content of about 1 to 6 per cent of the aqueous phase.
For reaso~s of organoleptical acceptability the lactose
content of the products of the invention should be no more than
about ~% by weight of the aqueous phase, preferably 0.1 to 1.5%
of the aqueous phase. A minimum lactose content further
improves the stability of the emulsion, particularly at a
relatively low pH and/or storage temperature. If desired -
e.g. for matching a sweet-butter taste impression - a little
lactose, or other suitable sweetening material can be added,
e.g. when lactose-reduced milk proteins or substantially lactose-
free proteins - such as solubilized caseinate are used -.
Most preferably, however, partially lactose-reduced milk

~05757~
proteins are used, e.g. proteins obtained by ultra-filtration,
gel filtration or dialysis of native milk proteins, by which
processes the proteins will retain about 10 or 15 to 20 or
25% of lactose (on dry matter).
Excellent results have been obtained by using either
partially lactose-reduced soluble milk proteins alone or
mixtures of such proteins with milk proteins that either by
salt formation (e.g. sodium caseinate) or complex building
(e.g. with sodium tripolyphosphate or citrate) were made
soluble.
The emulsion of the present invention should further
contain partial glycerides, as water-in-oil promoting emulsifiers,
particulary monoglycerides. Such partial glycerides should be
present in an amount of 0.1 - 1.5% of the emulsion, preferably
0.15 - 0.8%.
Suitably partial glycerides are used of saturated and un-
saturated fatty acids of which the proportion of unsaturated
fatty acid partial glycerides dominates the proportion of
saturated fatty acid partial glycerides and of which the
proportion of stearic acid partial glycerides dominates the
remainder of saturated fatty acid partial glycerides. Suitable
partial glycerides, especially monoglycerides of this type, are
disclosed in British patent specification No. 1,444,140.
Preferably substantially completely saturated partial
glycerides are used, which most preferably are dispersed in the
aqueous phase.
The addition of an effective amount of complexing agents
i.e. salts like alkali metal polyphosphates and citrates which
can react with polyvalent metal ions is advantageous,
especially when relatively hard water is used. Further, minor
ingredients e.g. salt, preservatives, flavouring agents,
colouring matter, etc., can be present in the low-fat spread
of the invention.
--6--

S7S7~
The low-fat spread of the invention can be prepared with
conventional equipment, but care should be taken that conditions
which adversely affect the physical stability of emulsions are
avoided.
During processing pasteurization of at least the aqueous
constituents is highly preferred.
The temperature and residence time of the aqueous phase
and/or the total emulsion in the pasteurization equipment
should be chosen in such a way that substantial precipitation
of the proteins is avoided.
Suitable pasteurization temperatures are from about 60 -
90C; the residence time should correspondingly be adjusted
to the selected temperature and local overheating should be
avoided, e.g. by intensive stirring.
Preferably the minor ingredients are dissolved or dispersed
in the aqueous phase, particularly under conditions of
sufficient shear forces so as to ensure that any gel structure
is substantially destroy~d. This treatment is preferably
effected before pasteurization of the aqueous phase and/or the
emulsion; otherwise insufficient pasteurization of gelled
particles can easily occur.
Alternatively at least part of the milk proteins can be
dispersed in the fatty phase of the low-fat spread; this
allows the expert after a little experimentation to prepare a
product which - depending on local taste-preference - is most
suitable.
The fat phase to be used can still contain part of the
aqueous phase, e.g. in case butter is used as starting material.
The water-in-oil emulsion according to the invention is
preferably prepared by combining melted butter or butterfat
with an aqueous phase containing all minor ingredients in
surface-scraped heat exchangers e.g. as described in "Margarine"
by A.J.C. Andersen, Pergamon Press, 2nd Ed. 1965.

~057571
The invention will now be illustrated by the following
Examples:
EXAMPLE I
A butter-based low-fat spread of the water-in-oil type was
prepared from the following constituents (all percentages are
by weight and based on the total product unless otherwise
specified):
40% fat (i.e. 25 kg or 47.8% butter, which contains 7.8%
aqueous phase)
3% water-soluble milk-proteinaceous powder (i.e. 1.5%
potassium caseinate, which is free from lactose, and
1.5% milk powder, obtained through dialysis, having
a protein content of 70% of the milk powder and a
lactose content of 25%)
0.4% of a hydrocolloid mixture of low methoxylated pectate
(80 parts) and carrageenan (20 parts)
0.5% of a 50/50 monoglyceride mixture of distilled un-
hydrogenated sunflower oil monoglyceride and dis-
tilled fully hydrogenated sunflower oil monogly-
ceride having an unsaturated fatty acid content
of 0.22%,
a stearic acid content of 0.22% and
a saturated fatty acid content of 0.28%
0.4% of common salt
7.8% of the aqueous phase derived from but:ter (see before)
47.9% of water.
The lactose content of the aqueous phase was about 0.8%.
The product was prepared as follows:
45.8% butter (percentaged based on ultimate product) was heated
in stirred vessel to 80C and local overheating which could
lead to denaturing of the butter proteins was carefully avoided.
Thereafter the product was rapidly cooled to 35~C.
The monoglyceride mixture was dispersed in the remaining

1057S7~
2% butter and the mixture was heated to 80C. 45% water was
heated to 45C and the hydrocolloid mixture, the additional
proteins and common salt were dispersed. The monoglyceride/
butter mixture was dispersed in the water/hydrocolloid/protein/
salt mixture and the aqueous product obtained was freed from
gas by careful heating to 80C in an evacuated stirred vessel
and cooling it down to 35C.
The pasteurized aqueous phase was slowly (10 litres/min)
dispersed in the pasteurized butter, each of which had a
temperature of 35C.
The remainder of the aqueous phase (2.9%) was heated to
100C and citric acid was dissolved to provide a 10% aqueous
citric acid solution.
This solution was added to the fat/aqueous phase system
(the premix) and a pH of 5.15 - 5.3 was obtained.
The blend obtained was pumped into a Votator* A-unit
revolving at 1200 rpm at a pressure of 1 - 3 atm. and cooled to
20 - 23C. The emulsion obtained was then treated in a second
Votator* A-unit (revolving at 900 rpm) and cooled to 15 - 18C
and finally worked in a post-working unit (1200 rpm) (an
uncooled, stirred and closed vessel) and packed. (Before
feeding the emulsion into the Votator* units, pasteurized butter
of 35C was circulated through these units, in order to effect
a sufficient degree of seeding).
The product obtained had a very fine water partition (the
majority of the water particles were 1 - 3 microns in diameter
and no particles of a diameter above 6 microns were present),
was very stable even at refrigerator temperatures, was
excellently spreadable, and no water separation could be
detected.
After storage for two weeks in closed containers at ambient
temperature the product was organoleptically assessed by a
skilled taste panel and it was concluded that it was still very
* Trade Mark

lQS7~7~
similar to butter; no signs of deterioration could be observed
even after storage for 7 days in opened containers.
EXAMPLE II
Example I was repeated, except that the proteinaceous
powder consisted of potassium caseinate only (lactose-free) and
that the pH was adjusted to 5.4. The emulsion obtained was fed
through the Votator* units as previously described and re-
circulated three times; during passage through the Votator*
the emulsion was seeded with butter to initiate the crystalli-
zation.
The product obtained was somewhat inferior to that of
Example I, particularly in respect of the emulsion stability.
The organoleptic properties were acceptable.
EXAMPLE III
Example I was repeated, except that the total fat content
was 50~; all remaining proportions were correspondingly adjusted.
Apart from spreadability at refrigerator temperature, which
was worse, the product was assessed to be almost as good as that
of Example I.
EXAMPLE IV
Example I was repeated, except that 8% proteinaceou8 powder
and 1.0% of a mixture consisting of 50 parts of high methoxy-
lated pectin and 50 parts of a monodiglyceride were used, the
fatty acid composition of which had been determined by GLC in
peak area per cent:
3.3% lauric acid
1.5% myristic acid
75.0% palmitic acid
22 % stearic acid
0.8% other fatty acids
The mono:di:tri glyceride ratio amounted to 38.9:5.0:56.1 in
peak area per cent. All remaining proportions were correspond-
ingly adjusted.
* Trade Mark
--10--

`' 105'7S71
The sequence of the process and the processing conditions
were as described in Example I, except that firstly salt and
hydrocolloids and the monodiglyceride mixture and finally the
proteinaceous powder were added to the heated water, and that
all the butter of a temperature of 28C was mixed with the
aqueous phase.
The pH was adjusted to 5.9.
The product obtained was almost as good as that of Example
I, except that upon storage in opened containers the product
lp deteriorated after 3 days.
E~AMPLE V
- Example I was repeated, except that another monoglyceride
mixture was used.
To 4000 grams of fat were added:
3.2 g of a molecularly distilled monoglyceride
derived from fully hydrogenated sunflower oil,
having the following fatty acid composition:
palmitic acid 7%
stearic acid 93~
15.0 g of a molecularly distilled monoglyceride
derived from unhydrogenated sunflower oil,
having the following fatty acid composition:
palmitic acid 7%
stearic acid 5%
oleic acid 28%
linoleic acid 60%
The total monoglyceride mixture contained monoglycerides
of:
stearic acid, 3.72g
linoleic acid, 9.0 g
total saturated fatty acids, 5.0 g
total unsaturated fatty acids, 13.2 g
Calculated on the fat, 0.12% of saturated fatty acid
--11--

1057571
monoglycerides and 0.33% of unsaturated fatty acid monogly-
cerides were present.
In contrast to the process described in Example I no
seeding with butter was necessary.
The product obtained was at least as good as that of
Example I.
EXAMPLES VI - XIII
Example I was repeated, except for the following differences:
.
Example Proteinaceous material added pH of open shelf
No. premix life at room
temp. in days
VI 2.5% K-caseinate and 0.5%
dialysed milk protein powder5.9 3
VII 2.5% Na-caseinate and 0.5%
ultrafiltrated milk protein
powder 5.9 3
VIII 2% K-caseinate and 1.0~ ultra-
filtrated milk protein powder5.7 4
IX 2.5% K-caseinate and 0.5%
ultrafiltrated whey protein
powder 5.6 5
X 0.3% Na-caseinate and 2.7%
whole milk protein powder 5.3 6
XI 1.5% Na-caseinate and 1.5%
whole milk protein powder 4.9 14
XII 2.8% K-caseinate and 0.2%
ultrafiltrated whey protein
powder 5.8 4
XIII 2.84~ Ca-coprecipitate *
dissolved by Na-tripoly-
phosphate and 0.16% ultra-
_ filtrated whey protein powder5.7
* The "coprecipitate" was obtained by addition of Ca-ions
to skim milk, heating the mixture to 90 - 100C, acidifying
it to pH 5.7 - 5.9, centrifuging and dissolving the dry matter
obtained with 0.3% trisodium polyphosphate (calculated on
protein) and heating the precipitate.
Excellent products were obtained; the importance of the
pH value in respect of the microbiological stability of the
-12-

OS'757~
products is evident from the above table.EXAMPLE XIV
Example I was repeated, except that 1.0% of hydrocolloid
was used consisting of pectin and guar gum in a weight ratio
of 1:2.
An excellent product was obtained.
EXAMPLE XV
Example IX was repeated, except that 0.8 per cent of sodium
caseinate, 0.2% whey protein and 2% hydrocolloid were used.
All other percentages were adjusted accordingly.
The resulting product was similar to that of Example I.
Even at a pH value of 4.5 it tasted less acid than sour-
cream-butter. A slightly mealy taste was observed after two
weeks' closed storage.
EXAMPLE XVI
Example I was repeated, except that in addition to the
ingredients described 6% of hot-swelling potato starch was
added to the aqueous phase (i.e. about 3.5% of the product).
The product obtained had a more margarine-like texture and
exhibited a bit more gluey mouth feel, which found a split
preference.
EXAMPLE XVII
Example I was repeated, except that the fat phase consisted
of 24% butterfat and 16% sunflower-seed oil and the water phase
was adjusted to pH 5.1.
In contrast to Example I the blend obtained had to be
cooled down to 6C in the Votator* A-unit in order to obtain a
stable emulsion. Product properties were similar to those of
the product of Example I, except that it was somewhat softer
at ambient temperatures.
EXAMPLE XVIII
Example I was repeated, except that no monoglycerides
were added to the fat phase but 0.5% of the saturated mono-
* Trade Mark
-13-

S~S71
diglycerides mentioned in Example IV was added to the water
phase. In this way a very good foam depression was achieved
on dispersing the ingredients in the water phase.
Product properties were similar to those of the product
in Example I.
EXAMPLE XIX
.
Example XVIII was repeated, except that the product
contained 3% dialysed milk protein only, and that the pH was
adjusted to 4.9.
An excellent, slightly sweeter product was obtained.
-14-

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Administrative Status

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Event History

Description Date
Inactive: IPC deactivated 2013-11-12
Inactive: IPC assigned 2013-01-31
Inactive: First IPC assigned 2013-01-31
Inactive: Expired (old Act Patent) latest possible expiry date 1996-07-03
Grant by Issuance 1979-07-03

Abandonment History

There is no abandonment history.

Owners on Record

Note: Records showing the ownership history in alphabetical order.

Current Owners on Record
UNILEVER LIMITED
Past Owners on Record
None
Past Owners that do not appear in the "Owners on Record" listing will appear in other documentation within the application.
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Document
Description 
Date
(yyyy-mm-dd) 
Number of pages   Size of Image (KB) 
Claims 1994-04-21 2 58
Abstract 1994-04-21 1 17
Drawings 1994-04-21 1 5
Descriptions 1994-04-21 13 446