GB1564681A

GB1564681A - Process for degumming fatty glycerides

Info

Publication number: GB1564681A
Application number: GB412678A
Authority: GB
Original assignee: Cadbury India Ltd
Current assignee: Mondelez India Foods Pvt Ltd
Priority date: 1978-02-01
Filing date: 1978-02-01
Publication date: 1980-04-10

Description

(54) A PROCESS FOR DEGUMMING FATTY GLYCERIDES (71) We, CADBURY INDIA LIMITED, a Company incorporated under the Indian Companies Act, of "Cadbury House" Bhulab hal Desai Road, Bombay 400 026, Maharashtra, India, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to the pre-treatment of fatty glycerides and in particular -to the degumming of certain non-traditional fatty glycerides like crude sal seed fat.

A number of methods exist for removing gums, resins, proteins and phosphatides from crude oils and fats. If the crude oil is not properly degummed, subsequent steps involved in the process of refining such as neutralisation, bleaching, deodorisation will not proceed smoothly and the final products will not be of high quality. Crude oils can be deslimed by treatment with steam, water or electrolytes, followed by settling, centrifugation or filtration with absorbents or other aids.

Most solvent extracted oils contain considerable amount of phosphatides and other mucilaginous materials which during storage form deposits in the storage tanks. A high gum content of the crude oil also increases refining losses considerably, as the gums will emulsify a considerable amount of neutral oil which is lost in the soap stock. Therefore, a separate degumming operation is necessary for solvent extracted oils.Thus, solvent extracted soya bean and cottonseed oils are degummed with special reagents, such as acetic anhydride and phosphoric acid prior to alkali treatment Crude sal fat obtained by solvent extraction contains varying amounts of non-glyceride impurities, such as free fatty acids, non-fatty materials generally classified as "gums" or phosphatides, colour pigments (chlorophyll) and certain undesirable phenolic compounds called ellagitannins in trace amounts. The unsaponifiable matter content in solvent extracted crude sal fat varies from 1% to 4% and even more than this sometimes. The alcoholic extract of sal seeds gives a positive test for the presence of phenols which has been identified as ellagic acid by ultra-violet and infra-red spectral data. Ellagic acid occurs widely in the plant kingdom.Ellagitannins are complex ester glycosides and occur largely in myrobalans and oak galls.

Crude sal fat when processed by conventional refimng techniques without subjecting it to a degumming operation is difficult to alkalirefine, bleach and deodorise, leaving a residual "tanny" flavour in the processed fat.

However, if processed sal fat, which exhibits properties very similar to cocoa butter, is to be used in confections, it should be free from any undesirable "tanny" flavour atter deodons- ation.

The present invention provides a method of degumming crude sal fat to remove the undesirable phenolic compounds and other nonglyceride impurities prior to alkali-refining.

Accordingly, the present invention provides a process of degumming crude fatty glycerides, especially crude sal fat, which comprises adding sodium acetate and acetic acid buffer to the normally solid crude fatty glycerides in molten fcrm and separating degummed fatty glycerides from the mixture so obtained.

When sal fat is subjected to the process of the present invention, the undesirable tannins and phenols especially ellagic acid, are removed along with gums and mucilaginous matter. The degumming is preferably carried out in the presence of a sodium acetate/acetic acid buffer in the pH range of 3.0 to 5.0, preferably at pH 4.5. This reagent, when added to crude sal fat as a 10% solution in quantities varying between 0.1 to 0.5% by weight of the fat, complexes ellagic acid and other phenols having properties similar to those of ellagic acid. The loose complex so formed is removed in the degumming operation along with gums and mucilaginous matter. The removal of ellagic acid and similar phenols from raw sal fat by this procedure has been confirmed by analysis using the spectroscopic properties of ellagic acid.

Preferably the crude sal fat is degummed by using a reagent, such as phosphoric acid and/ or citric acid, in addition to the sodium acetate/acetic acid buffer. The amount of phosphoric acid and/or citric acid used may lie in the range of 0.01% to 1% by weight of the crude fat.

The advantages of degumming raw sal fat by using the reagent of the present invention can be summarised as follws: a) Refining losses are reduced markedly.

b) Degummed and alkali-refined fat is easy to bleach.

c) The deodorised fat is free from undesir able "tanny" taste or any other odour re version.

d) The processed fat possesses good stability towards oxidative rancidity.

The invention is illustrated by means of the following Examples: EXAMPLE 1 0.5 by weight of sodium acetate/acetic acid reagent as a 10% aqueous solution was used as the degumming agent. It was added to the crude melted sal fat, at about 40or, with agitation. The temperature of the mixture was then raised to about 60or, with agitation and the mixture allowed to settle. The degummed melted fat was siphoned out by means of a skim pipe. The degummed melted fat was given a 10% by weight hot water wash and, after settling, the aqueous phase was removed.

TABLE 1 Ultra Violet Spectrascopic Analysis of Degummed Sal Fat Absorbance at Crude Fat Degummed Fat 255my 0.615 0.415 366 my 0.122 0.0278 EXAMPLE 2 This Example illustrates the invention as applied to crude sal fat in the presence of citric and phosphoric acids.

Crude sal fat containing 3% by weight of free fatty acids was degummed using sodium acetate acetic acid reagent as described in Example 1. It was then treated with 0.01% each of phosphoric acid and citric acid based on the weight of melted fat as a 10% solution.

The purpose of adding phosphoric acid or citric acid to the melted crude sal fat was to chelate any metallic impurities present in it and also to complete the degumming operation.

TABLE 2 Ultra Violet Spectrascopic Analysis of Degummed Sal Fat Absorbance at Crude Fat Degummed Fat 255 my 0.721 0.490 366 my 0.136 0.0745 The fat when degummed by the above methods was easy to refine, bleach and deodorise.

WHAT WE CLAIM IS: 1. A process of degumming crude fatty glycerides which comprises adding sodium acetate and acetic acid buffer to the normally solid crude fatty glycerides in molten form, and separating degummed fatty glycerides from the mixture so obtained.

2. A process according to claim 1, wherein the pH value of the sodium acetate/acetic acid buffer is in the pH range of 3.0 to 5.0.

3. A process according to claim 1 or 2, wherein the amount of the buffer used is 0.1 to 0.5 % by weight of the crude fatty glycerides.

4. A process according to claim 1, 2 or 3, wherein the crude fatty glycerides are also treated with phosphoric acid and/or citric acid.

5. A process according to claim 4, wherein the amount of phosphoric acid and/or citric acid used is 0.01 to 1% by weight of the crude fatty glycerides.

6. A process according to any of the preceding claims wherein the sodium acetate/ acetic acid buffer is added as a 10% aqueous solution, and the phosphoric acid and/or citric acid, when used, is added at a 10% aqueous solution.

7. A process according to any of the preceding claims wherein the crude fatty glycerides are crude sal fat.

8. A process of degumming crude fatty glycerides substantially as hereinbefore described in Example 1 or 2.

9. Degummed fatty glycerides, especially degummed sal fat, when produced by the process of any of the preceding claims.

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Claims

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in the range of 0.01% to 1% by weight of the crude fat.

The advantages of degumming raw sal fat by using the reagent of the present invention can be summarised as follws: a) Refining losses are reduced markedly.

b) Degummed and alkali-refined fat is easy to bleach.

c) The deodorised fat is free from undesir able "tanny" taste or any other odour re version.

d) The processed fat possesses good stability towards oxidative rancidity.

The invention is illustrated by means of the following Examples: EXAMPLE 1 0.5 by weight of sodium acetate/acetic acid reagent as a 10% aqueous solution was used as the degumming agent. It was added to the crude melted sal fat, at about 40or, with agitation. The temperature of the mixture was then raised to about 60or, with agitation and the mixture allowed to settle. The degummed melted fat was siphoned out by means of a skim pipe. The degummed melted fat was given a 10% by weight hot water wash and, after settling, the aqueous phase was removed.

TABLE 1 Ultra Violet Spectrascopic Analysis of Degummed Sal Fat Absorbance at Crude Fat Degummed Fat 255my 0.615 0.415 366 my 0.122 0.0278 EXAMPLE 2 This Example illustrates the invention as applied to crude sal fat in the presence of citric and phosphoric acids.

Crude sal fat containing 3% by weight of free fatty acids was degummed using sodium acetate acetic acid reagent as described in Example 1. It was then treated with 0.01% each of phosphoric acid and citric acid based on the weight of melted fat as a 10% solution.

The purpose of adding phosphoric acid or citric acid to the melted crude sal fat was to chelate any metallic impurities present in it and also to complete the degumming operation.

TABLE 2 Ultra Violet Spectrascopic Analysis of Degummed Sal Fat Absorbance at Crude Fat Degummed Fat 255 my 0.721 0.490 366 my 0.136 0.0745 The fat when degummed by the above methods was easy to refine, bleach and deodorise.

WHAT WE CLAIM IS: 1. A process of degumming crude fatty glycerides which comprises adding sodium acetate and acetic acid buffer to the normally solid crude fatty glycerides in molten form, and separating degummed fatty glycerides from the mixture so obtained.
2. A process according to claim 1, wherein the pH value of the sodium acetate/acetic acid buffer is in the pH range of 3.0 to 5.0.
3. A process according to claim 1 or 2, wherein the amount of the buffer used is 0.1 to 0.5 % by weight of the crude fatty glycerides.
4. A process according to claim 1, 2 or 3, wherein the crude fatty glycerides are also treated with phosphoric acid and/or citric acid.
5. A process according to claim 4, wherein the amount of phosphoric acid and/or citric acid used is 0.01 to 1% by weight of the crude fatty glycerides.
6. A process according to any of the preceding claims wherein the sodium acetate/ acetic acid buffer is added as a 10% aqueous solution, and the phosphoric acid and/or citric acid, when used, is added at a 10% aqueous solution.
7. A process according to any of the preceding claims wherein the crude fatty glycerides are crude sal fat.
8. A process of degumming crude fatty glycerides substantially as hereinbefore described in Example 1 or 2.
9. Degummed fatty glycerides, especially degummed sal fat, when produced by the process of any of the preceding claims.