Phase equilibrium data pertaining to the extraction of cottonseed oil with ethanol and 2-propanol

Summary Basic phase relation data have been obtained relative to the extraction of cottonseed oil with ethanol and 2-propanol, especially as affected by water in the solvent. Mutual solubility diagrams have been constructed for cottonseed oil with ethanol and 2-propanol of various aqueous concentrations. Tie-line data at 30° C. have been obtained for the ternary ethanol-cotton-seed oil-water and 2-propanol-cottonseed oil-water systems. These combined data will be of assistance in the selection of the most desirable temperatures and moisture concentrations in the solvent extraction of cottonseed with these alcohols. Comparison with results previously published for soybean oil suggests that the mutual solubility data for cottonseed oil and aqueous ethanols are applicable to other vegetable oils over a wide range of iodine values. In general, the results indicate that 2-propanol is the more desirable solvent since complete miscibility with the oil can be attained at temperatures below its normal boiling point even at moisture contents as high as 10% by weight whereas ethanol can tolerate only about 1.5% of water. High moisture contents result in more effective separation of the oil from the solvent when the miscella is cooled after extraction. Constant boiling aqueous ethanol and 2-propanol present the disadvantage of requiring greater than atmospheric pressure during extraction in order to attain complete miscibility with the oil. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

Detection of adulteration of cottonseed oil by gas chromatography

To detect adulterant vegetable oils in cottonseed oil, soybean, rapeseed, and ricebran oils were mixed into cottonseed oil extracted experimentally from seeds. These adulterated oils and the component oils were analyzed for sterols, fatty acids, and triglycerides by gas chromatography. In sterol analysis, stigmasterol was determined for adulteration with soybean and ricebran oils. Brassicasterol content seemed to be reliable as the indicator of adulteration for rapeseed oil. In fatty acid analysis, erucic acid for rapeseed oil and linolenic acid for soybean and ricebran oils were proof of adulteration. Triglyceride analysis was not so reliable as sterol analysis for detecting contamination, except that triglycerides with carbon-58, 60, and 62 indicate adulteration with rapeseed oil. Rapeseed oil (5%) and soybean and ricebran oils (10%) were the limits of detection for adulteration in cottonseed oil. Analysis of cottonseed oil from six refineries did not show positive indications of adulteration.     

Beef tallow in shortening preparations

Summary Experimental shortenings were prepared from various mixtures of tallow and cottonseed oil. Three series of shortenings were produced by somewhat different procedures: a) mixtures of tallow and cottonseed oil were hydrogenated and then catalytically rearranged; b) mixtures of hydrogenated tallow and cottonseed oil were rearranged; and c) mixtures of hydrogenated tallow and cottonseed oil were rearranged in the presence of 0.43% glycerine. Certain combinations and treatments of tallow and cottonseed oil produced shortenings which compared reasonably well with standard vegetable shortenings. Presented at the 29th Fall Meeting of The American Oil Chemists’ Society, Philadelphia, Pa., Oct. 10–12, 1955. A laboratory of the Eastern Utilization Research Branch, Agricultural Research Service, U. S. Department of Agriculture.     

The nutritive value of the Brazil nut oil

The chemical composition of the decorticated Brazil nut in the natural and fat-free state was determined, and the results confirm that this seed contains significant amounts of oil and protein. In three growth experiments carried out in rats, the Brazil nut oil had a nutritive value comparable to that of butterfat and the common table oils, olive oil, cottonseed oil, and corn oil. The use of levels of the Brazil nut oil up to 20% of the diet did not reduce growth or food consumption of rats. Heat treatment of the oil up to 120 min. at 140°C. did not reduce its nutritive value. The coefficient of digestibility of the Brazil nut oil was similar to that of the other oils, fresh and heated. The digestibility of the Brazil nut oil averaged 98% and was not affected by the heat treatment. The data indicate that Brazil nut oil is comparable to other animal and vegetable fats and oils in common use for human consumption. International Cooperation Administration fellow and Research Assistant. INCAP Publication I-150.     

Impacts of roasting oily seeds and nuts on their extracted oils

During industrial processing of seeds and nuts to produce edible oils, roasting is often applied before oil extraction. Moreover, seeds and nuts are generally consumed as snack food after appropriate roasting. These processes affect both the seeds and their extracted oils in many ways. Beside changes in macronutrients such as protein denaturation/degradation, oil oxidation, sugar pyrolysis and Maillard reactions, minor constituents such as fatty acids, sterols, phenolic compounds and tocols are also affected by roasting. On the other hand, studies have shown that antioxidant capacity of the roasted seeds and oxidative stability of the extracted oil could be greater than that of the unroasted counterpart. These improvements are attributed to the formation of Maillard reaction products, inactivation of oil degrading enzymes and facilitation of phytochemical extraction as a result of roasting.     

Norconidendrin: A new antioxidant for fats and oils

Summary and Conclusions The preparation of norconidendrin from western hemlock sulfite waste liquor has been described. Norconidendrin has been shown to possess antioxidant activity in both hydrogenated and unhydrogenated cottonseed and peanut oils, in a peanut oil essentially free of natural antioxidants, and in lard. Its activity in these products is comparable with that of other polyphenolic antioxidants. Norconidendrin, as well as the other polyphenols tested, exhibited greater antioxidant activity in the particular peanut oils used than in several other vegetable oils and still greater activity in substrates which contained only small amounts of natural antioxidants. The effectiveness of norconidendrin was found to be appreciably enhanced by the addition of acid-type synergists. It may be added either before or after deodorization with approximately equal effectiveness. When added before deodorization, it contributes no odor, color, or flavor to the finished oil. Practical applications of norconidendrin in preserving food products should be postponed until toxicity studies have been conducted. Presented before the 38th Annual Meeting of the American Oil Chemists' Society, New Orleans, Louisiana, May 20–22, 1947. One of the laboratories of the Bureau of Agriculture and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

Spectrophotometric estimation of soybean oil in admixture with cottonseed and peanut oils

Conclusion A spectrophotometric method has been described for the determination of soybean oil in admixture with cottonseed oil. The method provides a simple and rapid means of detecting gross adulteration of one oil with another and permits an accurate determination of linolenic acid for use as a criterion of the economic value of an oil mixture and as a guide in oil processing. The factor limiting the precision of the method is variation in composition of the cottonseed and soybean oils in the mixtures to be analyzed. Variations in composition affect the proportion of measured triene conjugation, due to the linolenic acid content of the soybean oil and the apparent linolenic acid content of the cottonseed oil. Thus, for unknown mixtures only average value corrections can be made for apparent linolenic acid content and the accuracy of a particular analysis will depend upon how well the composition of the oils in the particular mixture follows those of the average mixture. The method described can be extended to mixtures other than those of soybean and cottonseed oils. Thus, soybean oil may be determined in admixture with a peanut oil. In general, any oil which has an unsaturated fatty acid capable of producing triene conjugation upon alkali isomerization can be determined in the presence of any other oil containing no appreciable quantity of unsaturated fatty acids which can produce triene conjugation by such treatment. Presented before The American Oil Chemists’ Society, New Orleans, Louisiana, May 10–12, 1944. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

Chemical evaluation of egyptian citrus seeds as potential sources of vegetable oils

Seeds of the citrus fruits orange, mandarin, lime and grapefruit were analyzed. Petroleum ether-extracted oils of such seeds amounted to more than 40% of each. Physical and chemical properties of the extracted oils are presented. Samples of the extracted oils were saponified and the unsaponifiables and fatty acid fractions isolated. The isolated unsaponifiables and fatty acids were analyzed by GLC. GLC analysis of the unsaponifiables revealed compositional patterns differ-ent in number, type and relative concentration of fractions according to type of citrus seed oil, depending on the solvent system used for oil extraction and unsaponifiable matter isolation. The compositional patterns of the unsaponifiables were similar to that of cottonseed oil. Mandarin and grapefruit oils are free of cholesterol. The data demonstrate that the fatty acid compositional patterns of the oils differ; Mandarin seed oil contains the largest number of fatty acids, and grapefruit seed oil contains the lowest. The total amounts of volatile fatty acids in these oils are generally higher than those of other edible oils. Lime seed oil is similar, in the degree of unsaturation, to soybean oil. The orange oil pattern is similar to cottonseed oil. The amount of total essential fatty acids in lime seed oil is the highest of the oils studied.     

Comparative absolute yields of crude and neutral oils from variously prepared cottonseed meats

Summary Experiments utilizing cottonseed meats of diverse origin and composition were conducted for the purpose of determining the effect of the method of meats preparation on the yields of crude and neutral oil obtainable from differently prepared, comparable meats by solvent extraction. Three methods of meats preparation were employed,i. e., simple flaking of raw meats “as is”, tempering of cracked meats prior to flaking, and cooking by the modified hydraulic method developed for use with the filtration-extraction process. Commercial hexane was used as the extraction solvent. The experiments were carried out by procedures which eliminated the effects of any variables other than the method of preparing the meats for extraction The results of the studies showed that the method used in preparing cottonseed meats for extraction had a significant effect on the yields of crude oil obtained but that the yields of neutral oil, the valuable constituent of crude oils, were virtually unaffected. Analyses of the crude oils showed that the differences in crude oil yields were caused by the relative amounts of non-neutral oil materials in the crudes from the differently prepared meats. The greatest yields of crude oil were obtained from raw flakes, intermediate yields from tempered flakes, and the smallest yields from cooked flakes. The impurities content in the respective crude oils followed the same order,i. e., crudes from raw flakes were highest in impurities and lowest in neutral oil, crudes from tempered flakes were lower in impurities and higher in neutral oil, and the crudes from the cooked meats were outstandingly low in impurities and high in neutral oil. Virtually equal amounts of neutral oil were obtained from equivalent quantities of comparable meats regardless of the method used in preparing the meats for extraction. Presented at the meeting of the American Oil Chemists’ Society, Chicago, Ill., September 24–26, 1956. One of the laboratories of the Southern Utilization Research Branch, Agricultural Research Service, U.S. Department of Agriculture.     

Hydrogenated cottonseed oil as a substitute for palm oil in the production of tin plate and cold reduced sheet steel

Summary Work has been reported on the development of a substitute for palm oil, which is used to the extent of about 40 million pounds annually in the production of tin and terne plate, and in the cold reduction process for the manufacture of strip steel. This investigation included an examination of the chemical and physical properties of virgin and spent palm oils, especially with respect to the effect of these properties on the action of these oils in the tin bath. Based on the results of this investigation, and on information and cooperation of various producers and consumers of tin plate, efforts were made to produce from cottonseed oil a product which would be equal to or superior to palm oil with respect to its performance in the tin bath. It was found that, of the various types of selectivity hydrogenated cottonseed oils which were investigated, one having an iodine number of approximately 50 was best adopted as a palm oil substitute for use in the tin bath. The effect of heating hydrogenated cottonseed oils on the viscosity, rates of free fatty acid formation, rate of volatilization, effect of flux, and other factors were determined. Based on these results and further evaluation of the hydrogenated cottonseed oils by various producers of tin plate, specifications were formulated covering a product which it is believed will provide optimum performance and maximum life in the tin bath. Presented before American Oil Chemists’ Society, Chicago, Illinois, October 8–9, 1942.     

Applicability of the stamm reaction for rancidty

Summary The Korpaczy modification of the Stamm reaction for detecting rancidity in fats has been applied to a variety of fats and oils, including hog and beet fat, cottonseed oil, a number of other vegetable and seed oils, and a group of marine oils. This reaction has been shown to be generally inapplicable to vegetable, seed and marine oils but applicable to lard and beef fat.     

Purity assessments of major vegetable oils based on δ13C values of individual fatty acids

The fatty acid compositions and δ¹³C values of the major fatty acids of more than 150 vegetable oils were determined to provide a database of isotopic information for use in the authentication of commercial maize oil. After extraction of oils from seeds, nuts or kernels, and methylation, fatty acid compositions were determined by capillary gas chromatography. All compositions were within the ranges specified by the Codex Alimentarius. Gas chromatography combustion-isotope ratio mass spectrometry was employed to determine the δ¹³C values of the major fatty acids of the oils. A large number of pure maize oils and potential adulterant oils from various parts of the world were studied to assess the sources of variability in δ¹³C values. Such information is vital to establishing the compound specific isotope technique as a reliable means of assessing vegetable oil purity. Variability in δ¹³C values was related to the geographical origin of the oil, year of harvest, and the particular variety of oil. This suggests that the ultimate δ¹³C values of fatty acids are determined by a combination of environmental and genetic factors.     

Calculation of iodine value from measurements of fatty acid methyl esters of some oils: Comparison with the relevant American Oil Chemists Society method

A new calculation method for the determination of iodine value (IV) from measurements of fatty acid methyl esters is proposed. The method is based on the quantitative determination of fatty acid methyl esters of vegetable oils by capillary gas chromatography. IV is a measure of the number of double bonds in the unsaturated fatty acids in one gram of oil. The analytical methodology of its evaluation includes the use of rather health dangerous reagents, and for that reason is mostly avoided by laboratory analysts. A calculation procedure to determine the IV of oils from their fatty acid methyl ester composition is in use based on the American Oil Chemists’ Society (AOCS) method Cd 1c-85. A new calculation procedure for IV, based also on the evaluation of the fatty acid methyl esters of oils, was developed. The application of the proposed calculation methodology was checked with olive oil, corn oil, soybean oil, cottonseed oil, and sunflower seed oil. The proposed calculation gave results in better agreement with the Wijs method than with the relevant AOCS method.     

Characterization of oils from low-gland and glandless cottonseed

New varieties of cotton which contain few or no gossypol pigment glands are being developed. Commercial production of such varieties should contribute to improving meal quality and reducing the color problems encountered with cottonseed oil. Samples of gland-containing, low-gland, and glandless seed grown in California were obtained, and the oils were extracted and characterized. With regard to the over-all characteristics the oils from the low-gland and glandless seed were indistinguishable from regular cottonseed oil. Iodine values, contents of unsaponifiables, cloud- and pour-points, response to the Halphen test, and similar characteristics resembled those of commercial cottonseed oil. No differences were found in behavior during winterization. Determination of the component fatty acids by gas chromatography showed the fatty acid composition of the oils to be typical. Determination of the positions of the double bonds in the unsaturated acyl groups showed no differences between the oils from gland-containing, low-gland, and glandless seed. Ultraviolet, visible, and infrared spectra of the oils revealed no differences other than the presence of gossypol in the crude oil from the gland-containing seed. The infrared spectra of the unsaponifiable fractions obtained from the oils showed some differences, which were not believed to be important. Presented at the fall meeting, American Oil Chemists’ Society, New York, N.Y., October 17–19, 1960. Trainee, Institute of International Education, UNESCO (present address: Union of Burma Applied Research Institute, Rangoon, Burma). One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U.S. Department of Agriculture.     

Variables affecting the yields of fatty esters from transesterified vegetable oils

Transesterification reaction variables that affect yield and purity of the product esters from cottonseed, peanut, soybean and sunflower oils include molar ratio of alcohol to vegetable oil, type of catalyst (alkaline vs acidic), temperature and degree of refinement of the vegetable oil. With alkaline catalysts (either sodium hydroxide or methoxide), temperatures of 60 C or higher, molar ratios of at least 6 to 1 and with fully refined oils, conversion to methyl, ethyl and butyl esters was essentially complete in 1 hr. At moderate temperatures (32 C), vegetable oils were 99% transesterified in ca. 4 hr with an alkaline catalyst. Transesterification by acid catalysis was much slower than by alkali catalysis. Although the crude oils could be transesterified, ester yields were reduced because of gums and extraneous material present in the crude oils. Presented at the American Oil Chemists’ Society annual meeting, Chicago, May 1983.     

Preparation of pure palmitic acid and a by-product plasticizer from cottonseed oil

Summary A laboratory process has been developed which permits the isolation of a highly purified palmitic acid from cottonseed acids through the recrystallization of its cyclohexylamine salt from acetone and subsequent regeneration of the acid. The by-product, predominantly cyclohexylamine salts of the unsaturated fatty acids, can be modified and converted to morpholides which have shown promise as vinyl plasticizers. The morpholine salts can be obtained as a direct byproduct by the use of an appropriate mixture of cyclohexylamine and morpholine with the composite acid. By using an amount of cyclohexylamine closely equivalent to the saturated fatty acid content and sufficient morpholine to make up the residual neutralization equivalent of the composite cottonseed acids, the saturated acids can be isolated as cyclohexylamine salts. The stripped mother liquor will consist essentially of the morpholine salts of the unsaturated acids. Pure palmitic acid is obtained by recrystallization of the cyclohexylamine salts. The complete process is applicable to fatty acids from other natural glyceridic oils in which the dominant saturated acid bears a ratio to the other saturated acids closely paralleling that in cottonseed oil. The process is not operable with partially hydrogenated oils. Presented at the 49th Annual Meeting of the American Oil Chemists’ Society, Memphis, Tenn., April 21–23, 1958. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

Solubility of tristearin and hydrogenated cottonseed oil in certain aceto- and butyroglycerides

Summary Tristearin, triolein, 1,2-diaceto-3-olein, an acetoolein product, and 1,2-dibutyro-3-olein were prepared. Also a commercial, refined, and bleached cottonseed oil was hydrogenated to obtain products having iodine values of 29.3 and 1.1. Solubility measurements were made for the mixtures tristearin-triolein, tristearin-1,2-diaceto-3-olein, tristearin-1,2-dibutyro-3-olein, and for hydrogenated cottonseed oils in the aceto-olein product and cottonseed oil. In mixtures containing from 0.18% to approximately 30% of tristearin the solubility on a weight basis was unaffected by the nature of the oil. On a mole fraction basis the tristearin was most soluble in the triolein and least soluble in the 1,2-diaceto-3-olein. Hydrogenated cottonseed oil appeared to be about equally soluble, on a weight basis, in the aceto-olein product and cottonseed oil. Presented at the 45th annual meeting of the American Oil Chemists’ Society, San Antonio, Tex., April 12–14, 1954. One of the laboratories of the Southern Utilization Research Branch, Agricultural Research Service, United States Department of Agriculture.     

The difficultly extractable lipides of cottonseed meats,their composition and effect on the refining characteristics of the crude oils

Summary and Conclusions Crude lipides fractions were produced from raw, tempered, and cooked meats from two lots of cottonseed by a series of successive stepwise extractions, designed to obtain fractional portions of the total lipides in the order of the difficulty of their extraction. The proximate composition of the crude lipides fractions was determined. It was found that the composition of successive lipides fractions varied with the degree of exhaustiveness of extraction. The fractions obtained by more exhaustive extraction contained greater amounts of undesirable non-neutral oil material and lesser amounts of desirable neutral oil. It was also established that the method used in preparing meats for extraction was of paramount importance in its effect on the composition of the crude lipides obtained. The crude lipides fractions from raw and tempered meats contained large amounts of impurities while the crude lipides fractions similarly obtained from cooked meats were relatively low in impurities. Crude oils equivalent to varying degrees of total lipides extraction were reconstituted from the crude lipides fractions and evaluated for refining characteristics. The impurities content of the reconstituted oils varied as the degree of total lipides extraction and increases in the impurities content of the oils were generally reflected in disproportionate increases in refining losses and/or refined oil color. The oils obtained from the cooked meats at all degrees of extraction were outstandingly low in refining losses as compared to the oils from the raw and the tempered meats. Presented in two parts at the spring meeting, American Oil Chemists’ Society, New Orleans. La., Apr. 18–20, 1955, and at the fall meeting, Philadelphia, Pa., Oct. 10–12, 1995. One of the laboratories of the Southern Utilization Research Branch, Agricultural Research Service, U. S. Department of Agriculture.     

Additional physical properties of diglyceride esters of succinic and adipic acids

Summary Diglycerides of the fat-forming acids yield, on esterification with succinic, adipie, and other shortchain dibasic acids, a poteutially useful series of compounds ranging from hard, high-melting waxes to viscous oils which will not crystallize. A number of the properties of these compounds were determined in carlier investigations. In the present investigation additional properties of the 1,3-diolein and 1,3-distearin esters of succinic and adipic acids were determined. Surface and interfacial tensions were measured and found to be similar to those of cottonseed oil. The smoke points also were found to be similar to that of cottonseed oil. The ability of the compounds to thicken cottouseed oil was measured and found to be somewhat better than that of highly hydrogenated cottonseed oil at levels above about 12%, and the mixtures were relatively resistant to fat leakage. In hardness the distearin esters of succinic and adipic acid were comparable to carnauba wax and were over twice as hard as highly hydrogenated cottonseed oil. Permeability to water vapor was found to be greater than that of highly hydrogenated cottonseed oil and carnauba wax and about equal to that of cocoa butter. Presented at the 33rd Fall Meeting, American Oil Chemists' Society, Los Angeles, Calif., September 28–30, 1959. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

Vitamin E und Haltbarkeit von Pflanzenölen

Vitamin E and stability of vegetable oils. The main occurrence of vitamin E basing on its synthesis and its lipophilic character are vegetable oils, seeds, nuts and cereals. The most important task of tocopherols are their antioxidative capacity in food lipids. The antioxidative potential of tocotrienols in comparison to their corresponding tocopherols is lower. According to the chemical structure γ- and δ-tocopherol are more effective than α-tocopherol. An improvement of the antioxidative capacity is possible by controlled adding to tocopherol compounds as well as by the use of synergists like ascorbylpalmitate. For this improvement the composition of fatty acids, the tocopherol content in native oil and the circumstances of the oxidation should always be considered.