US3187019A - Brominated oils - Google Patents

Description

United States Patent of Illinois No Drawing. Filed Jan. 24, 1%4, Ser. No. 339,889 6 Claims. ((11. 260-348) The present invention is directed to the manufacture of brominated oils; more particularly, it is concerned with the manufacture of brominated oils of much improved stabilities.

Brominated oils are used to adjust the specific gravity of citrus oils so that a flavoring emulsion can be made which will stay suspended in beverages. As well as flavor, the emulsion provides cloud to give the drinks good appearance.

Citrus oils used as flavoring agents are insoluble in water and have a specific gravity of about 0.85, while they are used in beverages with a specific gravity of about 1.0 for dietetic drinks or about 1.03 to 1.06 for sugar-sweetened drinks.

Brominated oils are dense liquids which can be blended with the citrus oils to balance the specific gravity with respect to the finished drink. From this oil mix, an emulsion can be prepared which will have good stability in the beverage.

Unfortunately, brominated oils suffer from the grave disadvantage of having low stability; in fact, the stability of known brominated oils is so low that manufacturers routinely mark their product as having a limited shelflife because it will gradually degrade when exposed to air or normal summer temperatures for prolonged periods of time. Upon degradation, color, acidity and/or rancidity develop and obviously the product is no longer acceptable to the food and beverage industries.

It is thus an object of the present invention to provide a bromine-ted oil oat high stability. It is a particular object to provide a method of manufacturing a brominated oil with high stability against formation of color and acids. It is 'a further object to provide a brominated oil with an extended shelf-life and which does not develop discoloration or increased acidity upon storage.

These and other objects are accomplished by the method of the present invention whereby an unsaturated oil, in which 8797% of the initially present canbon-to-c-arbon unsaturations are brominated, is treated with an epoxidizing agent such as peracetic acid, periormic acid, or other organic per-acids, until substantially all doublc-bonds are saturated. The excess acid is then neutralized by the addition of a base and the formed insoluble by-prod-ucts are removed by filtration, centrifugation, or other separation techniques.

In a general embodiment of the present invention, an unsaturated oil such as sesame oil, safilower oil, cottonseed oil, olive oil, corn oil, soybean oil, or a mixture of such unsaturated oils, is treated with bromine whereby the amount of bromine added is calculated in such a way that an unsaturation of about 343% of the initial unsaturation remains in the oil. The treatment with bromine is carried out at a temperature between 10 and 30 C. under agitation. Ordinarily, the bromination takes place almost instantaneously and the completion of the reaction is easily detectable by the disappearance off the red color of the free bromine. Brominations of unsaturated oils are described in more detail in the Journal of Laboratory and Clinical Medicine, volume 16, pages 36 if, of 1930, and numerous more recent publications. However, the prior methods require neutralization at the end of the bromination, while in the method of the present application, neutralization is neither required nor desired at this point. The reaction mixture is directly 3,187,019 Patented June 1, 1%65 treated with 1-3% by weight of commercial 40% per.- acetic acid or a similar amount of another organic peracid at a temperature between 0 and 40 C. The mixture is stirred :for at least one hour at this temperature and the excess acid is then removed by neutralization with a base or an alkaline agent such as sodium carbonate, potassium carbonate, calcium hydroxide, and the like. Preferably, an alkaline agent is selected which has the capability of forming a hydrate. This agent is then added in its anhydrous form so that any water formed as by-product is absorbed and gets eliminated in the subsequent removal step for the salt. After filtration, the oil is very light-colored, stabilized against acid and color development, and bland in taste like the original unsaturated oil.

For the purpose of illustration, reference is made to the following example:

Example To 125 grams of sesame oil of iodine value is added 83 grams of bromine under thorough agitation while the temperature is maintained below 30 C. by means of external cooling. After the red color of the bromine disappears, 4 grams of 40% commercial peracetic acid is added and the mixture is stirred for 2 hours at room temperature. Thereafter, the excess acid is removed by the addition of suflicient sodium carbonate to neutralize the mixture. The reaction mixture is then filtered and a pale-yellow pure oil is obtained. This oil is stable to discoloration and the formation of acids for more than six months, as shown by frequent color inspections and titrations with dilute sodium hydroxide.

The above outlined process can also be carried out in the presence of a solvent but the use of such a solvent is not recommended because the subsequently necessary elimination thereof produces additional costs and with most solvents, a last trace is almost impossible to remove, leaving an objectionable odor in the oil.

Substantially the same stability can be achieved by substituting the sesame oil in the above example with commercially available cottonseed, corn, olive, soy-bean or safflower oil. In all cases, the color remains the same over a period of six to twelve months, while a nonepoxidized but neutralized sample will turn dark enough to block light transmission within days or a few weeks. In all cases, the acidity determined by titration with 0.1 N aqueous sodium hydroxide remains constant for at least six months, while acid formation is apparent Within several weeks for the corresponding control samples which are 'brominated as above and neutralized but not epoxidized.

Actually, the amount of bromine for the bromination of the initial vegetable-oil does not have to be calculated for a substantial deficiency to produce a brominated oil with 3-13% of the initial unsaturation retained, since it is known that a complete saturation is generally somewhat more difiicult to achieve. Ordinarily, a slightly undercalculated equimolar amount will give excellent results. Actually, many of the commercially-available brominated oils fall into the above range of 313% re maining unsaturation which is reflected by an iodine number of from about 3-10; they represent excellent starting materials for the process of this invention.

It will be obvious to those skilled in the art that the estimated shelf-life of the birominated oils according to the present invention is of great importance [for the food and beverage industries where these brominated oils have been used in the past to blend with essential oils in order to attain a specific gravity as close as possible to the specific gravity of the liquid with which they are to be mixed as flavoring agent. To attain any desired specific gravity, the proportions of the brominated/ epoxidized oil of the present invention and the essential oil are calculated by the convenient and simple way of the Pearson-Square method.

For the purpose of this invention, almost any organic per-acid can be used for the epoxidation of the remaining double-bonds of the unsaturated oils. Among the most economical organic pereacids usetfiul for this purpose are performic, peracetic, perpropionic, .perbutyric, perbenzoic acids, and the like. Whatever acid is used for this purpose, it is preferably selected in such a way that it is Water-free. The used per-acid as Well as the normal carboxylic acid from which it is derived (and which is (formed again as a by-product) should be odorless, colorless and pure, and preferably of low toxicity even though the acid residue is subsequently eliminated by the neutraliz ation and filtration. The amount of the per-acid to be used should be at least 0.3% by weight of the brominated oil but 'it may be as high as 5% or even although no advantage is gained in using more than about 2% of the pure per-acid by weight of the brominated oil.

Others may practice the invention in any of the numerous ways which will-be obvious to those skilled in the art by thepresent disclosure. All such practice of the invention is considereda part hereof provided it falls withinthe scope of the appended claims. I claim:

1. The process of producing a stable oil essentially comprising the steps of adding at least 0.3% by weight of an organic per-acid to a brominated vegetable oil in which 87-97% of the initially present double bonds are saturated with bromine,

mixing said components at a temperature between 0 and 40 C. for a period of at least one hour, neutralizing said mixture, and

removing the immiscible lay-products from said mixture. 2. The process peracetic acid.

3. The processof claim 1 wherein the mixture is neutralized with an alkali metal carbonate.

' 4. The processiof claim 1 wherein the formed byproduct is removed by filtration.

5. A brominated vegetable oil wherein 87-97% of the initially present unsaturation -is saturated with bromine and substantially all remaining Mind. 7

6. An oil according to claim 5 wherein the initial unsaturated oil is selected from the group consisting of sesame oil, olive oil, corn oil, soybean oil, safflower oil and cottonseed oil.

of claim 1 wherein said per-acid is IRVING MARCUS, Primary Examiner.

NICHOLAS s. RIZZO, Examiner.

double-bonds are epox-

Claims (1)

1. THE PROCESS OF PRODUCING A STABLE OIL ESSENTIALLY COMPRISING THE STEPS OF ADDING AT LEAST 0.3% BY WEIGHT OF AN ORGANIC PER-ACID TO A BROMINATED VEGETABLE OIL IN WHICH 87-98% OF THE INITIALLY PRESENT DOUBLE BONDS ARE SATURATED WITH BROMINE, MIXING SAID COMPONENTS AT A TEMPERATURE BETWEEN 0* AND 40*C. FOR A PERIOD OF AT LEAST ONE HOUR, NEUTRALI2ING SAID MIXTURE, AND REMOVING THE IMMISCIBLE BY-PRODUCTS FROM SAID MIXTURE.