US2063602A - Stabilization of animal and vegetable fats and oils - Google Patents

Description

-Patented Dee. s, 1936 A PATENT OFFICE STABILIZATION OF ANIMAL AND VEGETABLE FATs ANn on.s

Jam s K. Hunt and George H. Latham, Wilmmgton, Del., assignors to E. I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware No Drawing. Application February 15, 1935,

Serial No. 6,644

20 Claims.

This invention relates to the stabilization of animal and vegetable fats and oils and particularly unsaturated fatty glycerides.

It is well known that animal and vegetable fats and oils tend to become rancid and discolor on storage. It is not definitely known just what causes this deterioration. It has been suggested that this deterioration is due to oxidation or to the. action of micro-organisms or to hydrolytic reactions caused by enzymes or due to minute amounts of impurities. Such deterioration is highly objectionable and renders the fats and oils unfit for many uses. Many attempts have been made to overcome this deterioration. It has been proposed to add various substances to the fats'and 'oils to inhibit or retard such deterioration. Among 'such substances are certain aromatic amino compounds. These substances have not proved to be entirely satisfactory for the reason that the compounds are too expensive, too volatile, discolor the fats and oils, are toxic, or give the fats and oils an objectionable odor or taste.

An object of our invention is to provide a new class of compounds to be incorporated in animal and vegetable fats and oils which will retard or inhibit deterioration of the fats and ,oils and will not have the disadvantageous properties of prior compounds employed for this purpose. A furwill be particularly suitable for use in edible fats and oils. Other objects are to provide new compositions of matter and to advance the art. Still other objects will appear hereinafter.

These objects may be accomplished in accordance with our invention which comprises incorporating in animal and vegetable fats and oils small amounts of sugar amines. By a sugar amine, we mean an amine of a reducing sugar containing a carbon chain of at least five carbon atoms. These amines may be employed as the free bases or as the salts of aliphatic acids, particularly the long chain fatty acids. The free bases may be represented by the formula wherein R represents a carbon atom of a sugar nucleus containing a carbon chainof at least ther object is to provide such compounds which 1 five carbon atoms and each of R1 and R2 represents hydrogen or a carbon atom of an organic group. The sugar amines may also be defined as amino alcoholsin which the alcohol radical is a normal open-chain radical containing at 5 least five carbon atoms and having a hydroxyl group attached to each carbon other than the one attached to the nitrogen. The sugar amines may be employed as their aliphatic ethers or esters, that is, the lfydrogens of one or more of the OH groups may be replaced by alkyl, hydroxy alkyl or acyl radicals, such as ethyl, hydroxy ethyl or acetyl radicals. However, such ether and ester type compounds are generally less effective and hence are less desirable.

Some of the simple primary sugar amines are known and the methods of preparing them are also known. Some of the simple secondary and tertiary amines and the methods of preparing them are known. Some of the secondary and tertiary amines and methods for preparing them are disclosed in the copending applications of P. L. Salzberg and R. B. Flint, Serial Nos. 635,- 045; 635,046 and 635,047 filed September 27, 1932. issued as Patents 2,016,962, 1,994,467 and 2,016,- 963, respectively.

In general, the method of preparing the secondary and tertiary amines comprises reacting the sugar with a primary or secondary amine and hydrogen at superatmospheric pressures and temperatures in the presence of hydrogenating catalyst. For example, methyl glucamine may be prepared by placing 80 parts of methyl amine, 100 parts of commercial glucose and 80 parts of water into a pressure vessel with 9 parts of a reduced nickel catalyst comprising reduced nickel supported on kieselguhr, the reduced nickel comprising of the catalyst. Hydrogen may be then introduced to a pressure of 2000 lbs. and the ingredients agitated vigorously during the heating. Hydrogen absorption begins at 100 C. and is complete in fifteen minutes. The maximum temperature during this time should be about 120 C. The product may be separated from the 45 catalyst by filtration, and the filtrate evaporated until crystallization occurs. Methyl glucamine may be recrystallized from this residue as a white solid melting at 127-128 C. The reaction taking place may be represented as follows:

NHOH:

Under certain conditions sugar amines may be alkylated by reacting with an alkyl halide or an alkyl sulfate at room temperature or slightly above room temperature in order to form secondary and tertiary amines such as dodecyl glucamine and dodecyl methyl glucamine. How ever, this process is generally less satisfactory for I the preparation of pure monoalkyi sugar amines than the one given above.

Other amines which may be employed for preparing secondary and tertiary sugar amines coming within our invention are monoethyl amine, diethyl amine, monopropyl amine, dipropyl amine, monobutyl amine, dibutyl amine and monoand,di-amines of the higher saturated aliphatic type such as dodecyl and octadecyl amine, phenylethyl amine, monoand di-benzyl amine-qr other aralkyl amines, and aryl amines such as aniline, toluidine, and naphthylamine and mixed amines such as phenyl ethyl amine, methyl benzylamine and the like. Thus R1 and R2 in the formulae may be methyl, ethyl, isopropyl, butyl amyl, isoamyl, octyl, dodecyl, cetyl, cyclohexyl, .cyclohexanol, phenyl, phenylol, naphthyl, and the like.

Among the sugars which may be employed to produce amines coming within our invention are: glucose, fructose, xylose, ribose, lyxose, lactose, arabinose, mannose, rhamnose, galactose. sorbose, sorbinose, gulose, and talose.

The sugar nucleus may be alkylated by the usual methods of preparing ethers such as by treating with an alkyl halide or alkyl sulfate such as ethyl chloride or diethyl sulfate to replace the hydrogens of one or more of the OH groups by the alkyl group. The degree of alkylation will depend primarily upon the proportions empl y o I The sugar nucleus may also be acylated. The method of preparing such compounds comprises treating the sugar or sugar amine with an acid halide or anhydride such as acetyl chloride or acetic anhydride under anhydrous conditions and at superatmospheric temperatures. The resulting compounds are esters in which the hydro gens of one or more of the OH groups are replaced by the acid radical. The degree of acylation will depend primarily upon the proportions tion the preferred modes of carrying the same of the ingredients employed.

The hydrogens of one or more of the OH groups of the sugar radical may be replaced by hydroxy alkyl groups by reacting the sugar or the sugar amine with an alkylene oxide such as ethylene oxide in the cold. For example, 50 parts of glucamine may be dissolved in 50 parts of water and cooled to 20 C. 17.2 parts of ethylene oxide may then be "added. The reaction takes place without heating. The formula of the re-. action product is not definitely kno but it is believed that the reaction probably takes place as follows:

The salts of the sugar amine bases may be prepared by melting the acid and the base together or, where either the acid or the base or both are liquids, merely by mixing.

In general, we have found'the secondary amines and their salts to be most efiective. This is particularly true of those compounds in which each group is an organic group devoid of acidic substituents. Also, the sugar amines containing long chain aliphatic hydrocarbon'groups are aside as indicated above.

more soluble in the oils and fats and less soluble in water than the amines which do not contain these groups. Further, the aliphatic acid salts, particularly those of' long chain fatty acids are generally more soluble in the oils and fats than the free bases. By the term "long chain", as employed herein and in the claims, we mean carbon chains of at least 8 carbon atoms.

The proportion of amine employed in any oil will depend upon the particular oil, the particular amine and the degree of stabilization desired. We have found that from about 0.1% to 1.0% is satisfactory in most cases. The amounts to be used in practice may vary from about 0.001% up to 2% or more. It will generally be preferred to employ amounts of not more than about 0.1% in edible fats and oils.

Some of the compounds which we have found to be particularly satisfactory for our purpose are as follows:

methyl glucamine CH1OH(CHOH)(QHr-IL'-CH1 glucamine CH:OH(CHOH)4OH:NH:

dodecyl methyl glucamine CH;OH(CHOH)4CH:- C1|Hu H I dodecyl glucamine onlomonomlonr-i s-cunu H amyl glucamine CH:H(OHOH) OHgI IC5Hu H butyl xylamine CHIOH(CII-OH)QCHI NLOQHT H methyl lructamine CH:0H(CHOH)zCH-l"I-CH:

HQOH

H methyl gelactamine CH1OH(CHOH)(CHFI-CH1 H H methyl glucamine steal-ate CH 0H(CH0H)4CH:-I i

OOCCnHu In order to more clearly ustrate our inveninto eifect, and the advantageous results to be obtained thereby, the following examples are iven Example 1 ethylene oxide ,---a

filter paper 5" 2" were saturated with the well shaken solution and the excess oil absorbed between clean white blotting paper. The impregnated filter papers were placed in carefully cleaned, glass-stoppered bottles and stored at 65 C. in the dark, and in duplicate experiments, at room temperatures (25-30" C.) in diffused llght. The control or blank tests were similarly carried out on the control portion of oil set All tests were run in Days for rancidity to develop at Discoloration Agent of oil 65 0. Room temp.

None (untreated oil)- 5 22 Methyl glucamine. 77 37 None. None.

. Example? To aportion of 'melted lard, 1% of methyl 7, glucamine was added and stirred in at about 100 C. A second portion of the same lot of lard (containing no stabilizer) was used as a blank or control. After cooling, rancidity tests were run with these portions of lard at 65 C. as in Example 1. The untreated lard became rancid. in two days, whereas the treated lard required seven days to become rancid.

Example 3 A sample of cold pressed castor oil was divided into two portions. To one was added 0.5% of methylglucamine. The other portion was used as a blank or control. Both portions of oil were heated to 100 C., as this aided in dissolving the methylglucamine in the oil to which it was added. After cooling, filter papers were impregnated with the oils, and rancidity tests were made at 65 C. as in Example 1. The results are given in the following table:

Days for rancidity Discoloration Agent to develop at 65 C. oi oil None (untreat- 53 ed castor oil).

Methylgluca- 148 mine.

D efini tely yellow. None.

Note that, in this case, the inhibitor prevented the discoloration on aging that normally occurs in castor oil.

Example 4 A sample of air-blown cottonseed oil was divided into two portions. One portion was employ'ed as a blank or c'ontrol while to the other was added 1% of methylglucamine, based on the oil. Rancidity tests were run at 65 C. as in Example 1. The untreated oil became rancid in one day. The treated oil did not become rancid in 33 days.

' Example 5 A portion of China-wood oil was heated to 420 F., requiring 1 hour, held at that temperature for one hour and then cooled. To this oil was added 0.03% of cobalt as cobalt linoleate.

' Such a composition skins over in air very badly the untreated portion. It may be noted that,

when such oil skins over, the body of the oil is protected from the atmosphere by the film or skin.

Example 6 Refined cottonseed 011 containing 1% of glucamine was tested for rancidity at 65 0., as in Example 1 along with a portion of untreated cottonseed oil of the same lot. The untreated oil became rancid in six days, whereas the treated oil required ten days to develop rancidity. Neither of the oils discolored.

Example 7 Refined cottonseed oil containing 1% of ethanol glucamine was tested as in Example 1. Results:

Days for rancidity to develop Agent Discoloration 65 0. Room temperature None (untreated oil)- 4 8 None. Ethanolglucamine 7 15 None.

Example 8 -Refined cottonseed oil containing 1% of dodecyl methyl glucamine was tested as in Example 1. The results are given in the following table:

Time for rancidity to develop Discoloration Agent of on Room tem- 650 perature None (untreated oil).-- 4 8 None Dodecyl methylglucamine 7 11 None Example 9 Acetylated methyl glucamine was prepared by placing 312 parts (3 mols) of acetic anhydrlde and 31 parts of anhydrous sodium acetate in a reaction vessel and heating to reflux temperature. 75 parts of methylglucamine of a mole) was added in small portions. The boiling was continued for 25 minutes, the mixture cooled, poured into 1200 parts of ice water and was then neutralized with a 40% solution of potassium hydroxide. The precipitate, which settled out, was filtered oil and recrystallized from 150 parts of hot water. The melting point of the material was 114-115 C. Analysis indicated that the formula of the material was one of the following:

OH: NH-CH:

l N-COCH: CH1

(CHOCO CH1): l

(CHOCOCHQA CHzOC O CH3 I (31110 COCH:

. 1% of this material was incorporated in refined cottonseed oil and tested at room temperature as in Example 1. The untreated oil developed rancidity in eight days, whereas the treated oil required twelve days to develop this rancidity. Neither oil discolors.

Example 10 A pie crust was prepared consisting of approximately fat containing 1% methylglucamine. A check or control pie crust, containing the same amount of the same fat but without a stabilizer, was also prepared. Each pie crust was divided into portions, one of which was crushed and the other remained uncrushed. All

' indicate a rancid state of the lard).

Example 11 A portion of lard was treated with 0.1% methylglucamine, based on the weight of lard. Another portion of lard'was' untreated. Air was passed through the two portions at the same rate at 100 C. The time required for each sample to reach a peroxide value of 20 milli-equivalents of peroxide per .1000 g..of lard was determined (this peroxide value having been previously found to It was found that 7 hours was required for the control portion of lard to reach a peroxide value of 20, while the time required for the lard containing 0.1% methylglucamine was 54 hours. These tests were run according to the technique described in Oil 8: Soap, June, 1933, p. 105-9.

Erample 12 Samples of refined cottonseed oil, containing 1%, on the basis of the oil, of the following sugar amines, were tested for rancidity at 65 C. .as in Example 1 with results indicated below:

' Hours for rancidity Discolora- Antioxidant to develop at 65 0. tion of oil None (untreated oil) 176 None.

Dodecyl glucamlne 382 None. Amyl glucamine-- 360 None. Butyll xylamine I 528 None. Met yl fructamine.-- 494 None. Methylgalactamine- 260 None. Methyl glucamine stearate 528 None.

The above examples are merely illustrative of some of the compounds of our invention and some of the compositions in which they may be employed.- Our compounds may be employed to inhibit development of rancidity in other animal 'mayonnaise, salad 'oils and the like.

and vegetable fats and oils such as linseed oil,

China-wood oil, other esters of linoleic, linolenic, and eleostearic acids, cottonseed oil, castor oil, olive oil, rape seed oil, cod liver oil and other fish oils, coconut oil, palm oil, corn oil, peanut oil, sesame oil, neatsfoot oil, butter fat, lard, beef tile lubricants, clear lacquers for coating paper,

and the like. Furthermore, the edible oils are frequently employed in the preparation of pastries and otherbakery products, potato chips,

pounds will be found to be effective for inhibiting rancidity and discoloration of the oils and fats in these various tynesof compositions.

Our compounds have been brought into intimate contact with the skin without having any harmful effect thereon. Small amounts of the materialsthemselves have been eaten ,by human beings without any harmful effects being detected. Accordingly, it appears that our compounds are harmless or non-toxic to human beings; "They are derived from sugars which arev in themselves foodstufls. They do not-cause objectionable taste or odor or discoloration of the Our comfats and oils in which they are incorporated when employed in the proportions indicated. They have low volatility so that they have little tendency to volatilize during heating of the fats such as occurs during cooking or in deepfat frying 6 operations. Some of them are more soluble in the fats and oils than in water. For all of the above reasons, our compounds are particularly adapted for use in edible fats and oils. This is an important feature of our invention.

Other sugar amines falling within our invention are:.

Primary amines Fructamine Rhamnamine Xylamine Galactamine Ribamine Sorbinamine Lyxamine Sorbamine Lactamine Gulamine Arabinamine Talamine Mannamine Secondary amines Ethyl glucamine Methyl xylamine Isopropyl glucamine Butyl xylamlne N-butyl glucamine Benzyl xylamine Isobutyl glucamine Ethyl galactamine Octyi glucamine Methyl mannamme Benzyl glucumine Amyl arabinamine Cyclohexyl glucamine Diglucamine Cyclohexanol glucamine Dixylamine Phenylglucamine Difructamine 'Hydroxyplienyl glucamine Reaction product of glue- Napht hyl glucamines amine and xylose Tertiary amin'es D imethyl glucamine Octyl methyl glucamine Difurfuryl glucam ne Didodecyl xylamine Dimethyl fructamine Salts Glucamine stearate Methyl glucamine oleate Glucamine oleate Xylamme stearate As has been pointed out heretofore, our amines may be employed as the free bases or as'the salts of aliphatic acids and particularly of the long chain or fatty acids. Among the fatty acids which may be employed to form the salts of Eleostearic acid Abietic acid and the like Stearolic acid Some of the free amines of our invention are oil and fat soluble and substantially insoluble in water. This is particularly true of the sugar amines containing long chain hydrocarbon groups. These amines may be incorporated in the fats and oils merely by mixing. In stabilizing oils or fats in which the sugar amines are only slightly soluble, the sugar amine to be employed should be added and well stirred into the oil and the mixture allowed to stand until a saturated solution is obtained when the clear oil or fat can be decanted off or filtered, or the undissolved amine can be allowed to remain in the oil or fat or composition containing it, as a dispersion. In some cases the sugar amines will dissolve more readily in hot oil or fat. .The least soluble cangenerally be rendered soluble by employing them as their salts or soaps, particularly, of the fatty acids.

While we have disclosed the preferred form of our invention and the preferred modes of carrying the same. into effect, and indicated some of the variations and modifications that may be made 7 therein, it will be readily apparent to those skilled in the art that many other modifications and variations may be made therein without departing from the spirit of our invention. Accordingly, the scope of our invention is to be limited solely by the appended claims, construed as broadly as is permissible in view of the prior art.

We claim:

1. Compositions comprising animal and vegetable fats and oils having incorporated therein a sugar amine compound in which the sugar radical containsat least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and to carbon and hydrogen solely, in an amount suffrcient to inhibit deterioration of the fats and oils on storage.

I 2. Compositions comprising animal and vegetable fats and oils having incorporated therein a secondary sugar amine compound in which the an amount suificient to inhibit deterioration of the fats and oils on storage.

3. Compositions comprising animal and vegetable fats and oils having incorporated therein a secondary sugar amine compound in which the sugar radical contains at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and to carbon and hydrogen solely and having one amino hydrogen replaced by an aliphatic group, in an amount suflicient to inhibit deterioration of the fats and oils on storage.

4. Compositions comprising animal and vegetable fats and oils having incorporated therein an amino alcohol compound in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount suflicient to inhibit deterioration of the fats and oils on storage.

5. Compositions comprising animal and vegetable fats and oils having incorporated therein a secondary amino alcohol compound in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount sufdcient to inhibit deterioration of the fats and oils on storage.

6. Compositions comprising animal and vegetable fats and oils having incorporated therein an amino alcohol compound in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to thgamino nitrogen and having a hydroxyl group attached to each carbon except thecarbon attached to the nitrogen and in which at least one amino hydrogen has been replaced by a hydrocarbon radical, in an amount sufficient to inhibit deterioration of the fats and oils on storage.

7. Compositions comprising animal and vegetable fats and oils having incorporated therein a secondary amino alcohol compound in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carton atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen and in which the ,other substituent of the secondary amino group is a hydrocarbon group, in an'amount.sufii cient to inhibit deterioration of the fats and oils on storage.

8. Compositions comprising animal and vegetable fats and oils having incorporated therein an N-aliphatic substituted amino alcohol compound in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount sufiicient to inhibit deterioration of the fats and oils on storage.

9. Compositions comprising animal and vegetable fats and oils having incorporated therein a mono N-aliphatic substituted amino alcohol compound in which the alcohol radical is an openchain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount sufiicient to inhibit deterioration of the fats and oils on storage.

10. Compositions comprising animal and vegetable fats and oils having incorporated therein a mono N-alkyl substituted amino alcohol compound in which the alcohol radical is an openchain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount sufficient to inhibit deterioration of the fats and oils on storage.

11. Compositions comprising animal and vege-- table fats and oils having incorporated therein an amino alcohol in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount sufficient to inhibit deterioration of the fats and oils on storage.

12. Compositions comprising animal and vegetable fats and oils having incorporated therein a secondary amino alcohol in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount sufiicient to inhibit deterioration of the fats and oils on storage.

13. Compositions comprising animal and vegetable fats and oils having incorporated therein a mono N-aliphatic substituted amino alcohol in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount sufficient to inhibit deterioration of the fats and oils on storage.

14. Compositions comprising animal and vegetable fats and oils having incorporated therein a mono N-alkyl substituted amino alcohol in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each a salt of an aliphatic acid and an amino alcohol in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount=sumcient to inhibit deterioration of the rats and oils on sttfiage.

16. Compositions comprising animal and vegetable fats and oils having incorporated therein a salt of a longchain aliphatic acid and an amino alcohol in which the alcohol radical is an openchain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen'and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount sufflcient to inhibit deterioration of the fats and oils on storage.

17. Compositions comprising animal and vegetable fats and oils having incorporated therein a salt of a long chain aliphatic acid and a mono N-aliphatic substituted amino alcohol in which the alcohol radical is an open-chain radical containing at least 5 carbon atoms one carbon atom being singly bonded to the amino nitrogen and having a hydroxyl group attached to each carbon except the carbon attached to the nitrogen, in an amount sumcient to inhibit deterioration of the fats and oils on storage.

18. Compositions comprising animal and vegetable fats and oils having incorporated therein methylglucamine in an amount sufficient to inhibit deterioration of the fats and oils on storage.

' 19. Compositions comprising animal and vegetable fats and oils having incorporated therein dodecylglucamine in an amount sumcient to inhibit deterioration of the fats and oils on storage.

20. Compositions comprising animal and vegetable fats and oils having incorporated therein Wmethylglucamine stearate in an amount suflicient to inhibit deterioration of the fats and oils on storage.

JAMES K. HUNT. GEORGE H. LATHAM.