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Two methods were compared for quantitative determination of trace amounts of mesityl oxide and diacetone alcohol in acetone-extracted oilseed meals and flours. In the first, a simple, rapid and direct gas chromatographic procedure, a 0.04 g sample of oilseed meal or flour was placed between 2 small glass wool plugs in a liner of the injection port of a gas chromatograph. Water-saturated molecular sieve 5A (1.1 g) was added over the glass wool sandwich, and the liner was placed in the heated injection port and firmly secured. Mesityl oxide and diacetone alcohol, and other volatiles, were eluted rapidly from the sample onto the column by the combined action of heat, moisture, and carrier gas. The components then were resolved readily by temperature-programed gas chromatography on a 2 ft × 1/4 in. Porapak P column. The second method, which is time consuming and tedious, is a modification of the Todd azeotropic distillation procedure and was included, for comparison, as a conventional measure of the concentrations of mesityl oxide and diacetone alcohol. Samples of oilseed meals and flours were analyzed by both methods. The results are compared, and the relative merits of the two procedures are discussed.

Lauryl alcohol and 6-hydroxycaproic acid have been prepared from the ozonolysis products from both petroselinic acid and its ethyl ester by reduction with sodium borohydride. Satisfactory conversion of the ozonolysis product from ethyl petroselinate to lauryl alcohol and ethyl 6-hydroxycaproate was also achieved by catalytic hydrogenation, but the hydrogenation product was contaminated with small amounts of diethyl adipate and ethyl laurate as indicated by gas liquid chromatography. A procedure has been devised using ion exchange resin for the conversion of sodium 6-hydroxycaproate to 6-hydroxycaproic acid without the concomitant formation of lactones or polyesters.

Epoxidized jojoba oil has been evaluated as a light and heat stabilizer for vinyl chloride containing plastics and its properties, intercompared with those of other epoxides representative of three major classes of oxirane stabilizers. The results obtained show that epoxidized jojoba oil is a satisfactory thermal and ultraviolet stabilizer for both TCP and DOP plasticized stocks and has no adverse effects on the plasticizer properties of these materials. In general, epoxidized jojoba oil was found to be equivalent to or, in some instances, superior to the other epoxides tested.

The relation between fatty acid compositions, tocopherol contents, and autoxidative stabilities of a series of 16 crude oils from different varieties of peanuts has been investigated. It was found that the relative linoleic acid content of the oils is one of the major factors affecting the variations in the stabilities of the oils tested. With the exception of the oils from Runner peanuts the tocopherol compositions of the oils were not found to vary significantly, either in the nature and distribution of individual tocopherols, or in total tocopherol contents. The enhanced stability of the oils from the Runner peanuts may be due in part to the higher tocopherol contents of these oils. There is some evidence that crude peanut oils contain some non-tocopherol antioxidant and/or synergist.

The reaction of mercaptoacetic acid with methyl linoleate and with linoleic acid was investigated. The reaction proceeded at low and erratic rates, with and without catalysts, such as peroxides at various temperatures, but could be accelerated by use of a large excess of mercaptoacetic acid.

The acrylic and methacrylic acid esters of the mixed alcohols of jojoba oil have been prepared. These esters polymerize and copolymerize in the pattern of other acrylate and methacrylate esters. All are somewhat soft and show some promise as adhesives. The polymers crosslink and become insoluble on exposure to air.

Ten maleinated jojoba oil derivatives were screened as plasticizers in a standard polyvinyl resin formulation and as softeners for Buna-N rubber. Three of these, the methyl and butyl esters and hydrogenated methyl esters of maleinated jojoba acids, were comparable to the reference standard, DOP, as primary plasticizers for the vinyl resin. Three others were satisfactory only as secondary plasticizers. Six of the derivatives were comparable to the reference softener, dibutyl sebacate, as softeners in a Buna-N formulation and yielded rubbers meeting the low temperature flexibility requirements (−40°C.) of the automotive industry. Two of the six, those made with the butyl and hydrogenated butyl esters of maleinated jojoba acids, met the still more stringent low-temperature requirements of the aircraft industry (−55°C.).

cis-5-Eicosenoic acid and its methyl ester have been epoxidized. Preparation of an hydroxylactone through lactonizaton of both the 5,6-epoxy acid and the 5,6-dihydroxy acid has been investigated. 5-Eicosenoic acid has also been converted to γ-lactone through use of perchloric orp-toluenesulfonic acid. The preparation of several other related new compounds is described.

A simple, direct, gas chromatographic technique is described for the quantitative determination of residual hexane in extracted vegetable oils. The method if rapid and sensitive to one ppm hexane. The inlet liner of a gas chromatograph was packed with 1 1/2 in. glass wool, and 25 mg oil was added onto it. The sample was capped with a small plug of glass wool, and the liner was inserted in the heated inlet of the gas chromatograph. Residual hexane rapidly eluted onto the Poropak P column by heat, and carrier gas was resolved in 20 min by temperature programing between 70–180 C. The method appears useful for monitoring continuous solvent removal processes.

A simple, rapid elution gas chromatographic method was used for quantitative determination of acetone or 2-propanol in finely ground, extracted oilseed meals and flours. In the procedure, a 0.05 g sample of oilseed meal or flour was placed between 2 small glass wool plugs in a liner of the injection port of a gas chromatograph. Water (250 μl) was added over the glass wool sandwich, and the liner was placed in the heated injection port and firmly secured. Acetone or 2-propanol and other volatiles were rapidly eluted from the sample onto the column by the combined action of heat, moisture, and carrier gas. The components then were resolved by temperature programmed gas chromatography (GC) on a 1 ft x 1/4 in. Porapak Q column. A second gas chromatographic method, a volatilization procedure, was included in the study for comparison as a measure of the concentrations of acetone or 2-propanol. Samples of oilseed meals and flours were analyzed by both methods. The rapid elution procedure proved to be a simple and effective means of detecting residual acetone or 2-propanol in the samples. The values were very similar to those obtained by the volatilization procedure.

1. The extraction, processing, characteristics, and stability properties of nine batches of hexane-extracted rice bran oil were investigated. The oils were refined, bleached, and deodorized and their color and stability determined. Samples of the bleached oils were hydrogenated to approximately shortening consistency, deodorized, and the stability of the hydrogenated products determined. 2. Pilot plant extractions of five batches of rice bran yielded crude oils equivalent to 91% of the hexane-soluble portions of the bran. 3. The nine crude oils whose content of free fatty acids ranged from 2.0 to 6.3% were refined by the cup method with losses ranging from 12.0 to 23.5% although the neutral oil content of six crude rice bran oils ranged from 89.9 to 92.6%. 4. The Lovibond color of the nine refined oils ranged from 35 yellow and 4.5 red to 70 yellow and 9.5 red, and the color of the bleached oils ranged from 15 yellow and 1.5 red to 35 yellow and 3.2 red. 5. Steam-refining, employed in conjunction with alkali-refining, proved effective as a means of reducing the losses in refining rice bran oil. 6. The nine batches of refined, bleached, and deodorized rice bran oils had iodine values ranging from 101.3 to 105.7 and stabilities averaging 24 hours. 7. Nine bleached oils hydrogenated to approximate shortening consistency had iodine values averaging approximately 66 and stabilities averaging 370 hours. 8. Refined, bleached, and deodorized rice bran oil is bland but has some tendency toward flavor reversion. 9. The most outstanding characteristics of rice bran oil is its exceptional stability after hydrogenation.

A rapid and direct gas chromatographic procedure is described for the quantitative determination of residual hexane in finely ground oilseed meals and flours. A 0.04 g sample of meal or flour is added between two small plugs of glass wool in a liner of the injection port of a gas chromatograph. The liner with the sample is placed in the heated injection port and firmly secured, and 80 μl of water is immediately injected just above the glass wool which covers the sample. Volatiles which are rapidly eluted from the sample are then analyzed by temperature-programmed gas chromatography on a 2 ft × 1/4 in. Porapak P column. The results are comparable to the results obtained by the simple and efficient but more time consuming volatilization procedure. Since results are obtained within 20 min, this rapid procedure is very useful in monitoring desolventization processes.

A simple, rapid and direct gas chromatographic technique was developed for the examination of volatiles in salad oils and shortenings at the 10 ppb level without prior enrichment. The liner of the inlet of the gas chromatograph is carefully packed with volatile-free glass wool to allow slow diffusion of the sample on the glass wool, but to prevent seepage onto the gas chromatographic column. The liner with sample is inserted in the heated inlet, and the volatiles are eluted rapidly from the samples as the carrier gas flows through the linear and sweeps the volatiles onto the column, which is temperature-programed between 55 and 190C to resolve the volatiles. Numerous samples of salad oils and shortenings were examined, and the better quality oils had only small amounts of volatiles.

Methylcis,cis-5,13-docosadienoate has been isolated from the mixed methyl esters of the fatty acid moiety ofLimnanthes douglasii oil by a combination of low temperature fractional crystallization and fractionation of mercuric acetate adducts. The methyl ester and its free acid have been characterized.

Petroselinic acid of a grade which is suitable for most laboratory applications has been prepared by a single crystallization of the mixed fatty acids of parsley seed oil from 90% ethanol. A product of higher purity has been prepared from this acid by application of urea segregation techniques for the removal of saturated materials. No evidence of the presence of unsaturated fatty acids other than petroselinic acid was found in either of these samples when their ozonolysis products were examined chromatographically. On the basis of iodine values, assuming the absence of other unsaturated materials, the purities of the two preparations are 96.0 and 99.4%.

A simple volatilization procedure was developed for the determination of residual acetone in oilseed meals and flours. One gram of meal or flour and 0.2 g of water containing 0.4 mg of methanol are added into a 100 ml serum bottle, which is sealed and heated at 70 C for 5 hr in an oven. A 1 ml aliquot of the headspace gas is then analyzed by gas chromatography. The concentration of residual acetone is easily determined by comparing the ratio of the peak areas of acetone to methanol of the chromatogram with a calibration curve. Results are reproducible within ± 10%, and concentrations of a few ppm can be detected. This technique is much simpler and requires less operator time than other procedures available.

Glassware cleaned with a synthetic detergent instead of hot or cold chromic-sulfuric acid leads to improved reproducibility of the stability of fats and oils determined by the active oxygen method. When the glassware used in this method is cleaned with hot chromic-sulfuric acid, chromium compounds are absorbed within the glass walls and subsequently diffuse into the oil or fat thereby leading to erratic results. A method is described for cleaning the glassware used with the fat stability method which has given reliable results in the hands of the authors for more than a year, during which it has been in almost daily use.

A simple and very sensitive technique was devised to analyze volatiles in vegetable oils by direct gas chromatography. A large sample of oil is diffused on glass wool in an injection port liner. After the liner is inserted in the injection port, the volatiles are rapidly swept into the column of the gas chromatograph for analysis.