AU604494B2 - Enzymatic hydrolysis of beef tallow - Google Patents

Description

By: Registered Patent Attorney APPUICATiON ACCEPTED AND AME

NDMENTS

To: The Commissioner of PatentsCATION ACCEPTED AND AMENDMES..

'COMMONWEALTH OF AUSTRALIA ALLOWED S II I I. :-Vi COMMONWEALTH OF AUSTRA Patents Act 1952 COMPLETE S P EC IF I CAT I ON

(ORIGINAL)

Application Number Lodged Complete Specification Lodged Accepted Published This document contains the amendments made under Section 49 and is correct for printing.

Priority Related Art *4 17 September 1986 Name of Applicant COLGATE-PALMOLIVE COMPANY Address of Applicant 300 Park Avenue, New York, New York, 10022, United States of America Actual Inventor/s Edward Albert Tavss; Edward Eigen Address for Service F.B. RICE CO., Patent Attorneys, 28A Montague Street, Balmain N.S.W. 2041 Complete Specification for the invention entitled: ENZYMATIC HYDROLYSIS OF BEEF TALLOW The following statement is a full description of this invention including the best method of performing it known to us:ine Dasic appucanon reierrea LU I paragrapd u u us Loci ,araLnun is/athe first application made in a Convention country in respect of the invention the subject of the application.

New York, New York Declared at 2 (Z this 29th day of July 1987 CO TfCA P NLE COMPANY H.SC ylvester Assiitant General Counsel------- Industrial Property F. B. RICE CO, I I Background of the Invention and Prior Art This invention relates to the process of converting high melting fats, such as high grade beef tallow, into a high yield of fatty acids and glycerol, comprising the hydrolysis of Sbeef tallow in the presence of a minor amount of coconut oil by means of the castor bean lipase enzyme, at low temperatures, of about 25-50 0 C, and preferably about 37 0 C, for use in the production of soap. The high yield of fatty acids (98% conversion to Sfatty acids and glycerol), and the utilization of low temperature, in this process is accomplished by the addition of a minor amount c of coconut oil or other vegetable oil, which permits the emulsi- 'I fication of the beef tallow at lower temperatures, (37 0 This 0 iprocess eliminates undesirable thermal products and provides a savings in energy without resorting to undesirable additives.

SThe fatty acid and glycerol mixture is free of undesirable extraneous materials, because the coconut oil additive also hydrolyzes into fatty acids and glycerol.

Soap manufacturing is usually accomplished by saponification of high grade beef tallow with lye. This is a high C) temperature reaction which has become expensive in recent years SI due to the sharp rise in fuel costs. Hence, a low temperature reaction was sought, and enzymatic hydrolysis with lipases was investigated, as a substitute for the lye process, The optimum conditions of lipase reactions is usually Sas an emulsion at 370C. Unfortunately, the problem is that fats Ssuch as high grade beef tallow, do not start melting until at least 41 0 C to 500C. Therefore, they do not form emulrions at 37 0 C in water without additives. It is apparently fol this E A

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reason that in systems containing only beef tallow, water, and a Slipase preparation, the yields of fatty acids are always low or Snot -reported. Moskowitz et al, J. Agric. Food Chem., 25 1146 1 (1977). Constantin et al, Biochim. et Biophys. Acta, 43, 103 (1960). Ralston, Fatty Acids and Their Derivatives, pp. 274-279, Wiley (1948). Haley et al, J. Am. Chem. Soc., 43, 2664 (1921).

Raising the temperature of the lipase reaction did I not solve this problem, because of the rapid loss of stability of lipases at elevated temperatures. For example, pancreatic lipase loses 36% of its activity after 10 minutes at 50 0

C

S° because enzymes are denatured at raised temperatures.

In an attempt to overcome this problem, the reaction Ssystem was modified by the addition of metallic additives such as calcium and magnesium salts, which did give higher yields, i. as disclosed in Constantin et al (supra); Altschul et al, I Federation Proc., 18, 180 (1959); Kokusho et al, C C Jpn Kokai Tokkyo Koho 79, 95, 607 (1979); Benzonana et al, I Biochim. Biophys. Acta, 164, 47 (1968). However, the metal <j sodps formed in this reaction are hard soaps which provide i unsatisfactory foaming and cleansing action. Haley et al (supra) added petroleum ether as a fat solvent in order to get better physical contant between enzyme and substrate (beef I tallow) to increase or accelerate hydrolysis. This process however is one of considerable danger due to the high explosion potential of the solvent.

Since solid fats are very difficult to emulsify, a study on the selection of emulsifiers of natural (solid) fats was made by Lobreva, et al, -3- Micro -biologiya, 48, 53 (1979) in an attempt to increase lipolytic activity on fats. The emulsifying agents disclosed herein for the lipolysis of animal fats such as lard, beef and lamb fatsl are-Triton X-100, Triton X-305, egg albumen gelatin, gum arabic, lecithin and Tween-60. Not all of these agents reaction did not give a high yield of fatty acids and glycerol.

Furthermore, said emulsifying agents have the disadvantage of providing undesirable materials to the hydrolysis mixture.

Sf The use of the castor bean lipase in the hydrolysis of fats, and its preparation, are well known in the art, as disclosed in U.S. Patent No. 2,485,779, wherein a solvent extracted, ground castor bean meal, prepared at a temperature not exceeding S120 0 F is used in the partial hydrolysis of fish oil. Diethyl Sether extracted, ground castor seed kernels have been used in the hydrolysis of low quality industrial fats, as disclosed in S Trosko et al, Maslo-Zhir, Prom-st, 1977, 27; and in the hydrolysis; of sunflower oil, as disclosed in Meerow et al, Prikl. Biokhem.

Mikrobiol., 12 934 (1976). Castor bean lipase prepared by cen- _U 1 trifuging a homogenate of the kernels into a fatty layer which .c 'is extracted by ether in the presence of a saturated salt solution has been used in the hydrolysis of cottonseed oil, mono- and diolein, castor oil and a cottonseed oil emulsion, as disclosed in Altschul et al, (supra)l Haley et al, (supra) discloses a method of preparing a castor bean lipase by extracting the hull-free kernels with petroleum ether Shydrolysis of fats and oil. Ralston,. Fatty Acids and Their Derivative, Wiley, p. 276 (1948) discloses variations in the -4-

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method of preparing an active lipase from castor beans for use in the hydrolysis of fat containing 40-50% water, and in the Spresence of a small amount of acetic acid or an activating salt such as manganese sulfate. The general method includes grinding the dehulled seeds in water, filtering the solids, and centrifuging Sto form an emulsion. One variation thereof is grinding the dry seeds in cottonseed oil and centrifuging the mixture.

Another method includes extracting the macerated beans with petroleum ether, drying, pulverizing and sifting the product, which retains its original activity, over a period of ten years.

However, there is no disclosure of the low temperature hydrolysis of high melting point fats such as beef tallow with a non-stereospecific animal or vegetable lipase, particularly the castor bean lipase, in the presence of a vegetable oil emulsifying agent such as coconut oil at an acidic pH and a low temperature under 50 0

C.

Summary of the Invention It has now been found that the low temperature enzymatic hydrolysis of high melting fats such as beef tallow, utilizing a non-stereospecific animal or vegetable lipase enzyme, such as castor bean lipase, and a vegetable oil emulsifying agent such as coconut oil provides the almost quantative hydrolysis of the mixture of said beef tallow and coconut oil into fatty acids and glycerol free of extraneous undesirable materials.

Neutralization with sodium hydroxide forms a high grade soap free of contaminants).

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Accordingly, it is an object of the present invention to provide a process of hydrolyzing high melting fats, such as high grade beef tallow, into a high yield of fatty acids and glycerol, at a low temperature, with a non-stereospecific lipase such as castor bean lipase, in the presence of a vegetable oil emulsifying agent.

SAnother object of this invention is to provide a process of converting high melting beef tallow into fatty acids and Sglycerol, in high yield, at low temperatures by hydrolyzing a i mixture of beef tallow and a minor amount of coconut oil with the castor bean lipase enzyme.

SStill another object of this invention is to provide an enzymatic hydrolysis process of converting a mixture of a high melting fat and a low melting vegetable oil into a reaction mixture of fatty acids and glycerol free of undesirable minerals, i.e. thermal products and additives.

Another object of this invention is to provide an enzyme system to hydrolyze beef tallow and coconut oil 4 nto fatty acids (and glycerol) and neutralizing said fatty acids with NatH, Na2CO 3 or NaHC0 3 to form soap.

Additional objects and advantages will be apparent from a consideration of the following description and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention.

SThe objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

To achieve the foregqOng and other objects and in accordance with the present invention, as embodied and broadly -6- L i 1d i described herein, the process of this invention of converting high melting fats into fatty acids and glycerol comprises Shydrolyzing an emulsified mixture of a high melting beef tallow and about 10-25% by weight of the mixture of a vegetable oil, preferably coconut oil, in an aqueous medium, with a nonstereospecific animal or vegetable lipase enzyme, at a temperature of about 25-50 0 C, preferably 37 0 C, and at a pH of about 4-5.5, and recovering a final reaction mixture consisting of fatty acids, glycerol and lipase. The mixture is agitated for S) a sufficient period of time,Aabout 2 to 48 hours, to obtain Ssubstantially complete hydrolysis into fatty acids aid glycerol.

SThe final reaction mixture is free of undesirable materials, Sand consists of three layers, a fatty acid top layer, a lipase mixture middle layer, and an aqueous glycerin (sweet water) bottom layer. The layers may be separated. The fatty acid layer is skimmed off, neutralized with NaOH, Na 2 C0 3 or NaHCO 3 Ic and the resulting soap purified in the usual manner of soap manufacturers skilled in the art. The bottom layer is separated Sand the glycerine removed. The middle layer, containing more t than 50% of the original lipase still being active, is reused after adding a lesser quantity of fresh lipase.

The present invention also relates to a process of producing a high grade soap, free of undesirable additives, whict comprises hydrolyzing an emulsified mixture of a high melting fat and about 10-25% by weight of a vegetable oil in an aqueous medium, with a non-stereospecific animal or vegetable lipase at a temperature of about 25-50oC and at a pH of about 4-5.5, agitating the mixture for a period of time to obtain substantially complete hydrolysis into fatty acids and glycerol S separating the fatty acids from the glycerol, and neutralizing -7said fatty acids with an alkaline material to form a soap, free of undesirable additives. More specifically, the final reaction mixture consists of three layers, a fatty acid top layer, a lipase mixture middle layer and an aqueous glycerin bottom layer, and the process includes separating the top layer of fatty acid fran the final reaction mixture, and neutralizing said fatty acids with an alkaline material selected from the group consisting of sodium hydroxide, sodium carbonate and sodium bicarbonate to form a sodium soap substantially free of contaminants. The S resulting soap and glycerine is much lighter in color than the corresponding colors after sulfuric acid hydrolysis of fats or the high temperature sodium hydroxide saponification of fats.

More specifically, present invention relates to a process of hydrolyzing a high melting fat into a high yield of fatty acids for use in the production of soap free of undersirable additives, which comprises reacting a mixture of about S90-75% of a high melting beef tallow and about 10-25% coconut oil, with castor bean lipase, in about 20-50% water acidified to

S

r a pH of about 4-5.5 with a weak acid such as acetic acid, SCj phosphoric acd, phosphorous acid and carbonic acid, and at a temperature of about 37 0 C, agitating the reaction mixture for about 3-48 hours, to obtain a final reaction mixture consisting of three layers, a fatty acid top layer, a lipase mixtur in the middle layer and an aqueous glycerin bottom layer, separating the layers and neutralizing said fatty acids to form soap.

The middle layer which contains active castor bean lipase is r.eused intthe hydrolyzation process.

-8- The lipase enzyme used as a catalyst in the present hydrolysis process may be any animal or vegetable lipase which is non-stereospecific, i.e. the lipase must split the beta (middle carboxyl linkage) glyceride linkage at about the same rate as splitting the alpha (outer carboxyl) linkages. Suitable examples of non-stereospecific lipase enzymes are derived from castor bean, Candida cylindracea, Propionibacterium acnes, Rhizopus arrhizus, Staphylococcus aureus, Aspergillus flavus and Geotrichum candidum. Most lipases are stereospecific and therefore are ineffective, e.g., procine pancreatic lipase. Normally the extent of hydroylsis with these enzymes does not exceed 70%, whereas the non-stereospecific enzymes affect substantially complete hydrolysis.

The preferred lipase enzyme utilized herein is the castor bean lipase (ricinus communis). It is insoluble in water, and its activity is materially reduced by contact with water. The enzyme is stabilized by the presence of i 20 fats. It is rapidly inactivated by alkalis and functions only in a neutral or slightly acidic medium. This enzyme is activated by the presence of acids, preferably weak acids, such as acetic acid, phosphoric acid, phosphorous acid, carbonic acid, etc, which exerts the greatest accelerating effect. Accordingly, the optimum temperature for ricinus lipase action is abovt 37 0 C, and is inactivated at temperatures abovoi about 50°C. The amount of lipase used in the hydrolysis process is about i 3-15% of the substrate (fat and oil) by weight, if the lipase activity (LA) is unknown. If the LA is known, approximately on LA unit is used for every microequivalents of potential acid. (See N. Pelch and M.C. Kranz, Anal Biochem, 112, 219-222 (1981) for a procedure for determination of lipase activity).

9 I 4J I An additional advantage in the use of the castor bean lipase in the hydrolysis reaction is the ability to recover (separate) said lipase from the final reaction mixture and recycle it for use with a fresh substrate (fat and oil). This capability results from the natural immobilization property of castor bean lipase.

The castor bean lipase cannot be obtained commercially, but can be prepared as disclosed in the prior art previously discussed. The castor bean lipase utilized herein is prepared by dehulling castor beans, extracting the endogenous oils by grinding the dehulled beans in the presence of low boiling petroleum ether, filtering the ground bean pomace and discarding the filtrate, i.e. ether layer containing endogenous oils, repeating the extraction and filtration steps two more times, air drying the filtered pomace and recovering a lipase preparation in the form of the pomace. Another method of preparing the castor bean lipase enzyme without allezgen may also be used. This method of preparation should be considered because of the presence of a potent allergen in the bean. The dehulled bean is macerated in water, rather than petroleum ether and then centrifuged.

The fat layer is separated from the aqueous layer, and the aqueous layer is discarded. Since the lipase is in the spherosomes along with the endogenous oil, it will remain in the fat layer. The fat layer is extracted with petroleum either and saturated NaCl solution. The petroleum ether contains the endogenous oil, and is discarded. The saturated NaC1 solution contains the lipase in particulate matter.

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L r The optimum conditions for activity of castor bean lipase is about 25-500C and preferably about 370 and a pH of 4 to 5.5. A dilute acid such as 0.1N acetic acid, or other weak acids may be added to bring the pH to approximately i ,The amount of the castor bean lipase enzyme used in the present ohydrolysis process should be sufficient to effect a substantial degree of conversion of the beef tallow/coconut oil mixture into fatty acids and glycerol. Amounts of about 3 to 15% and preferably about by weight of thetriglyceride substrate mixture is used.

SIt has unexpectedly been found that the addition of I a vegetable oil such as coconut, corn, soybean, linseed, olive and palm oil, to the high melting point beef tallow Senables the beef tallow to i emulsify at a lower temperature, about 37 0 The lipase enzyme hydrolyzes the emulsified tallow/vegetable oil mixture almost quantitatively at the lower temperature with a resultant i saving in energy. The vegetable oil such as coconut oil also hydrolyzes into fatty acids and glycerol. Thus, no undesirable extraneous materials are present in the reaction mixture, thereby yielding a substantially pure soap upon neutralization I of the fatty acids with sodium hydroxide, sodium carbonate or sodium bicarbonate. The coconut oil constitutes a lesser amount by weight than the beef tallow in a mixture thereof.

SThe weight ratio of beef tallow to vegetable oil is about 75-90% to about 25-10% vegetable oil.

-I1 The data ui Table I show that a mixture of high may be used in soaps, was hydrolyzed approximately 98% into fatty acids at the described conditions. This is in clear contrast to results reported in the literature (Haley et al, supra), in which beef tallow was reacted with castor bean liaebtwsonly hydrolyzed dfX)ut 3% (Table II). In the latter case, coconut oil was absent.

The combined results clearly show that the addition of coconut oil unexpectedly yields a high conversion of the high melting beef tallow into fatty acids. It is believed that the coconut oil lowered the melting point of the beef tallow enough so that it would form an emulsion at 37 0

C.

TableI Extent of Castor Bean Lipase Hydrolysis of Fats and Oils0berd 'ILit. Enzyme Hlydrolysis Value *Olive oil (control 186-196 185 fl83:17 Tallow:coco 203-213 203 ~)*Saponification Value is the weight (mg) of KOU required t& 4 4 4 saponify 1S of fat, and is indicative of the extent of hydrolysft, uof the fats and oils. Tal Hydrolysis of Beef Tallow by Castor Bean tipase k Duration of Experiment (hrs,) txtent of Hvdrtsi 4' 24 482 72

SI

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ii The saponification value is determined by conventional methods described in the literature, M. Applewhite, Kirk-Othmr. Encycl. Chem. Tech., 3rd Ed., 9, 795 (1980). The saponification procedure utilized herein comprises adding 30 ml of absolute ethanol to a 2 to 3g sample in a covered flask, warming on a steam bath (50-600C), adding ml standardized 0.5N alcoholic KOH solittion and boiling for one hour, adding phenolphthalein indicator solution aid titrating with standardized 0.5N HCI to the disappearance of the pink color, and the saponification value is determined.

Saponification of fats and oils in the absence of lipase, to determine the maximum yield of soap available from fats and oils, was conducted on four substrates. Triolein and olive oil are standards used in literature. Beef tallow and coconut oil are components of the soaps prepared herein. The data in Table III shows that the observed results are in fairly good agreement with the literature values for the two standards and coconut oil, but low for beef tallow.

Table III Saponification Values (SV) Lit Obs.

Triolein 189 (calc) 190 Olive oil 186-196 182 Beef tallow 193-202 173 Coconut oil 250-264 253 -13- I 1

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i The advantages of the enzymatic hydrolysis process of present invention are multifaceted. Higher yields of fatty acids and glycerol are obtained, about 98% conversion. The use of lower temperatures resulted in considerable cost savings.

The use of vegetable oil such as coconut oil which also hydrolyzes into fatty acids arid glycerol yields fatty acids and glycerol free of undesirable additives. Said fatty acids yield a pure soap upon nuetralization with sodium hydroxide, carbonate, or bicarbonate. This low temperature hydrolysis reaction S' requires less utilization of energy, and therefore, less atmospheric pollution is produced. The use of a low reaction temperature in this process yields fewer undesirable thermal products, and a lighter color.

Detailed Descriptioniof the Invention I The following examples are merely illustrative of the invention and are not to be construed as limiting thereof.

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Example 1 Preparation of Enzyme Dehull 60g of castor beans. Grind the dehulled beans in a Waring blender in the presence of 600ml of low boiling (30-60 0 C) petroleum ether. The ether extracts endogenous oils Sfrom the beans. Filter and discard filtrate. Repeat extraction and filtration two more times. Air dry the crude lipase preparation.

Enzymatic Hydrolysis of Tallow/Coconut Mixture C Mix 1.6 7 g of the lipase preparation and 16.7g of an 83:17 mixture of high grade beef tallow and coconut oil, and cc of 0.IN acetic acid. Stir approximately 24 hours at 37°C. The final mixture consists of 3 layers, fatty acid on the top, lipase mixture in the middle, and sweet water (aqueous glycerine) on the bottom. The fatty acid layer is skimmed off, neutralized with NaOH, Na 2

CO

3 or NaHC0 3 and the resulting soap jpurified in the usual manner of soap manufacturers skilled in the art. The bottom layer is separated, and the glycerine removed.

The middle layer, containing more than 50% of the original S lipase still being active, is reused after adding a lesser Iquantity of fresh lipase.

SI Analysis of the extent of hydrolysis is determined I by adding 3.4 g of reaction mixture to 100 ml absolute alcohol, and tritrating to pH 9.5 with 0.1N alcoholic potassium hydroxide.

Results: 98% conversion to fatty acids and glycerol.

as I Lg LL I d U e L "a-.-LJW UU IL LU a L iL llL rI iLLL LIL I least 41°C to 50 0 C. Therefore, they do not form emulsions at 370C in water without additives. It is apparently foi this centrifuged. The fat layer is separated from the aqueous layer, which is discarded. The fat layer is extracted with 600 ml low boiling petroleum ether (30-60'C) and saturated NaC1 solution. The petroleum ether is discarded, and the NaC1 solution contains the lipase in particulate form. 1.67 g of this particulate lipase is used in the hydrolysis of the tallow/ coconut mixture in accordance with the process of Example 1.

Substantially complete hydrolysis into fatty acids and glycerol is obtained.

Example 3 The high melting beef tallow is melted at a temperature 1.67g of the lipase preparation of Example 1 is mixed with 16.7 g of the liquified fat and oil mixture, and 10 cc of 0.1N acetic acid for about 24 hours at 37oC. Substantally Suby complete hydrolysis into fatty acids and glycerol is obtained.

-16- .1 -16study on the selection of emulsifiers of natural (solid) fats was made by Lobreva, et al, -3m m -ilW~ ~c) Other weak acids may be substituted for the acetic acid in the examples, such as phosphoric, phosphorous or carbonic acid.

Lower melting point fats such as sheep tallow, industrial quality beef tallow, lard and butter may be used in the present lipase hydrolysis process.

Also, other vegetable oils such as corn, soybean, linseed, olive and palm oil may be substituted for the coconut oil in the examples.

It is understood that the foregoing detailed description is given merely by way of illustration and that variations may be made therein without departing from the spirit f the invention. The "Abstract" given above is merely for the convenience of technical searchers and is not to be given any weight with respect to the scope of the invention.

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Claims (14)

1. A process of converting high melting fats into a high yield of fatty acids and glycerol which comprises hydrolyzing an emulsified mixture of a high melting beef tallow and a vegetable oil in the weight ratio of 75-90% tallow to 25-10% oil, n an aqueous medium, with an animal or vegetable lipase which is non-stereospecific at a temperature of 25-50 0 C and at a pH of 4-5.5, agitating for a sufficient period of time to obtain substantially complete hydrolysis into fatty acids and glycerol, and recovering a final reaction mixtu):e consisting of fatty acids, glycerol and lipase.

2. The process according to Claim 1, wherein the mixture is agitated for a period of 3-48 hours to obtain substantially complete hydrolysis into fatty acids and glycerol.

3. The process according to Claim 2, wherein the vegetable oil is coconut oil.

4. The process according to Claim 3, wherein the mixture of the beef tallow and coconut oil is in the weight ratio of 83:17. The process according to Claim 2, wherein the lipase constitutes 3-15% of the weight of the tallow and vegetable oil mixture.

6. The process according to Claim 2, wherein the lipase enzyme is derived from castor bean, Candida cylindracea, Propionibacterium acnes, Rhizopus arrhizus, Staphylococcus aureus, Asperigillus flavus and Geotrichum candidum.

7. A process according to Claim 6, wherein the lipase enzyme is a castor bean lipase which is prepared by dehulling the castor beans, extracting the lipase by grinding the dehulled beans in the presence of a low boiling petroleum ether, filtering the ground beans, AL extracting and filtering the lipase again, air drying the 'AL, filtered lipase and recovering a dried castor bean lipase. e t ,u kLLt.Lov L -E'Vt -J- cordance with the present invention, as embodied and broadly

8. A process according to Claim 6, wherein the enzyme is a castor bean lipase which is prepared by macerating the dehulled beans in water, centrifuging the mixture to form a fat layer and an aqueous layer, separating the fat layer from the aqueous layer, extracting the fat layer with petroleum evher and saturated sodium chloride solution, and recovering the lipase from the sodium chloride solution.

9. A process of producing high grade soap which comprises hydrolyzing an emulsified mixture of a high melting beef tallow and 10-25% of a vegetable oil, in an aqueous medium, in the presence of non-stereospecific lipase enzyme, at a temperature of 25-50 0 C and at a pH of 4-5.5, agitating the mixture for a period of time to obtain substantially complete hydrolysis into fatty acids Sand glycerol, separating the glycerol from the fatty acids, and neutralizing said fatty acid with an alkaline material to form a soap free of undesirable additives. S 10. A process according to Claim 9, wherein the alkaline neutralizing material is selected from the group consisting of sodium hydroxide, sodium carbonate and I 4sodium bicarbonate.

11. A process according to Claim 9, wherein the lipase Senzyme is castor bean lipase. S12. A process according to Claims 7, 8 and 11 wherein the castor bean lipase is separated from the fatty acids and glycerol and is recycled for use in hydrolyzing a fresh imixture of fat and oil.

13. A process according to Claim 9, wherein the vegetable oil is coconut oil.

14. A process of hydrolyzing a high melting fat into a high yield of fatty acids for use in the production of a soap free of undesirable additives, which comprises reacting a mixture of 90-75% by weight of a high melting beef tallow and 10-25% coconut oil with castor bean lipase 4-5.5, agitating the mixture for a period of time to obtain substantially complete hydrolysis into fatty acids and glycerol O separating the fatty acids from the glycerol, and neutralizing in 20-50% water acidified to a pH of 4-5.5 and at a v temperature of 37 0 C, agitating the reaction mixture for 3-48 hours to obtain a final reaction mixture consisting of three layers, a fatty acid top layer, a lipase mixture middle layer and an aqueous glycerin bottom layer, separating the top layer from the other layer and neutralizing said fatty acids with a sodium salt selected from the group consisting of sodium hydroxide, sodium carbonate, and sodium bicarbonate to form soap. A process according to Claim 14, wherein the middle layer containing acti'e castor bean lipase is reused in the hydrolyzation process.

16. A process according to Claim 14, wherein the water is acidified with a weak acid.

17. A process according to Claim 16, wherein the weak acid is citric acid.

18. A process according to Claim 14, wherein the fatty acids are neutralized with sodium hydroxide. DATED this 12 day of September 1990 COLGATE-PALMOLIVE COMPANY Patent Attorneys for the Applicant: F.B. RICE CO.