Studies were made on low molecular weight components in the short chain triglyceride (SC-TG) fraction separated from crude lipids extracted from soybean seedlings of the fourth day, chiefly on the axis TG fraction. Fatty acids (FA) in the subfraction of SC-TG were composed chiefly of C16 : 0, followed by C14 : 0, and less amounts of C18 : 0 and C18 : 1 (Table-5). Considerable numbers of oxygenated FA were found in the aldehydogenic fraction obtained by acid methanolysis of TG (Table-8). Aldehydes present in a subfraction of SC-TG were chiefly C14 : 0, followed by C16 : 0, C18 : 8, and C18 : 1 (Table-1). Diols found in TG and SC-TG subfractions were C2C9 (Tables-8 and 9). The SC-TG fraction may be deviled into two main fractions : (1) A fraction comprising of com pounds such as short chain carbonyl compounds, alkanes, and alcohols with molecular weights less than 156 (Table-12); and (2) a fraction comprising of compounds such as TG having short chain FA and two types of diol derivatives, the diester type and 1-alkenyl ether ester type (Tables-13 and 14) with a molecular weight range of 470<600.

The objectives of the present study were to test the new analytical method, which has been developed by Urakami et al., for evaluation of oils used for frying various food items, simulating conditions actually encountered in family cooking and to compare the results obtained with those of model systems reported previously.Food items used were parsley, fritters of carrot and burdock, sweet potato, cuttlefish, and shrimp. They were fried continuously for 35min. per batch at 160180°C and frying was repeated 11 times, allowing the used oils to stand at room temperature for varying lengths of time. P/AP (the absorbance ratio of a polar one fraction at 233nm to apolar), AV, IV, and viscosity were determined at intervals.Despite some fluctuation of the last 3 values, particularly after standing 4 months, P/AP valnes showed a steady increase. This results give the good reliability for the new method in evaluation of an extent of deterioration. Large amounts of water depleted from food items and their large surface areas promoted deterioration of oils in such a manner as to give similar P/AP value in half of the period required for previous model system.

Polar fractions of fatty acid methyl esters (PFA) prepared from soybean oil heated 30 h by frying whale meat (Wh) and potato (Po) were subjected to fractionation by TLC and silicagel column chromatography (CC), monitoring each fraction for its UV-absorbance (at 233 nm). Highly UV-active fractions were analyzed by GLC and GC-MS to compare with the chromatographic patterns obtained from Wh and Po and to comprehend the nature of UV-active components. The fractions with Rƒ in a range of 0.230.96 by TLC (developed with petroleum ether-diethyl ether-ethanol 50 : 50 : 2) contributed nearly 90% of the total UV-absorption of PFA and amounted 5669%(on the weight basis) of PFA. These fractions showed strong intensities of absorption at 790795 and 765770 cm-1 in the IR region. The chromatograms obtained from both samples were quite similar, indicating similar nature of components being involved in both samples. The most remarkable UV-active subfractions obtained by CC (Rƒ 0.810.96) as well as five subsequent fractions (Rƒ up to 0.73) were found to be composed of short chain esters, chiefly C11C15, having UV-active conjugated systems such as diene, enal (or enone), and formylenol. Compounds having a carbonyl or a hydroxyl group in their mid-chains were also detected in GLC fractions eluted at high temperatures. On the other hand, a subfraction with its Rƒ 0.590.67 was found to be composed of chiefly C18 compounds either in an normal chain or cyclohexyl form having the conjugated systems as mentioned above and also a keto or hydroxyl group. Other compounds found were 8-phenyloctanal, C6 and C8-esters carring in their molecules the 5-oxo-1-cyclopentenyl residue, and dioctyl phthalate.

The purified lipid fraction (1.26% on the wet weight basis) from the nuts ofGinkgo biloba was found to be 90.6% neutral lipids, 7.5% polar lipids, and a very small amount of glycolipids. Main fatty acids in the triglyceride fraction were oleic and linoleic acids, and those in the phospholipid fraction were palmitic acid in addition to these unsaturated acids. The enzymic hydrolysis of the triglyceride and individual phospholipid fractions showed that only the triglyceride and phosphatidylcholine fractions contained relatively large amounts of unsaturated acids in their β-positions. The gas liquid chromatography-mass spectrometric analysis of the fatty acids of the steroid ester fraction indicated the presence of lignoceric, cerotic, montanic, and melissic acids as well as a lactone and compounds suspected to be phenolic acids containing long chain diols.

Soybean oils were heated at 180°C 5 hr/day up to 2030 hr by frying the following food items with an approximately equal in surface area ; potato, chicken, soybean curd, mackerel, whale meat, and green pepper. Amounts of water depleted from each food item was kept at a level of 25ml/hr/500g oil. Polar (P) and apolar (Ap) fractions were separated by TLC by applying either oil itself or its fatty acid methyl esters (the former is called the TG and the latter the FAMe method) and both fractions were monitored directly on the plate by an UV dual wavelength thin layer chromatoscanner at 230nm. Absorbances (expressed in terms of grams of oil or FAMe used for the chromatography) of P fractions increased with increase in heating time, while those of Ap remained fairly constant at low levels. Ratios of P/Ap for fresh oils remained less than 1 by both methods. At 20 hr of heating (which is considered to be a maximum useful life of the oil under the experimental conditions) the ratios by the TG and FAMe method were 47 and 24, respectively, depending on the freshness of oils used. Of the two methods, the TG method was found to be more convenient and an amount of sample necessary for a single analysis was only 0.2mg and the time required for examination of 24 samples/plate was 12 hr.

Choice of storage temperature, at room or low temperatures, for once heated oils and for fatcontaining processed foods at home has not drawn so much attention. Therefore, the conventional methods employed for fat analyses have been investigated if they can be used for detection of deterioration of heated soybean oil stored at low temperatures.Soybean oil heated for 30 min, 2 and 5 hr at 185°C was stored at 25, -5 and -25°C up to 150 days and each sample was analyzed for oxygen absorption (at 50°C), acid value, carbonyl value and fatty acid composion by gas liquid chromatography.The acid and carbonyl values of the samples stored in all the temperatures under consideration increased up to 3060 days, followed by decrease, indicating decomposition of acids and carbonyl compounds during the course of storage. Similarly, peroxide value of the samples stored at low temperatures increased up to 15 days, followed by decrease, whereas that of the samples stored at 25°C increased steadily. No significant differences in the proportions of fatty acids were observed between the samples before and after the storage when examined by gas liquid chromatography. However, the oxygen absorption curves obtained showed an absorption maxima or one or more plateaus when examined at a bath temperature of 50°C for 56 hr, and this may be attributed to the effects of some volatile compounds formed by heating and or autoxidation during storage. A white precipitate formed in the samples stored at -5°C was confirmed as triglycerides comprising relatively larger amounts of saturated fatty acids than those of soybeanoil.The decomposition of the oxygenated compounds as reflected by changes in acid, peroxide and carbonyl values in the samples stored at low temperatures suggests that these methods of analyses are not necessarily appropriate for detection of deterioration of oils stored at low temperatures, and therefore, further studies are necessary.

(1968). Changes in the Contents of Neutral Lipids and Composition of their Fatty Acids in Mung Bean Seedlings (Phaseolus Aureus) Archives Internationales de Physiologie et de Biochimie: Vol. 76, No. 5, pp. 823-832.

Authors previously reported that β-glycerylphosphoric acid (β-GP) exhibits antioxidant activity in methyl oleate but it does not decompose hydroperoxides. This report deals further study to elucidate mechanism for inhibition of autoxidation of unsaturated fatty acid esters by phosphate esters.Trimethyl, triethyl and tributyl phosphate (TBP) and β-GP were found as active in unsaturated fatty acid esters at a concentration range from 0.01 to 0.04%. Hexane solutions of methyl linoleate containing the same concentrations of TBP or β-GP showed a new absorption peak at 230 mμ, and the absorbancy at this peak tended to decrease as the concentration of the phosphate esters increased. Furthermore, another absorption bands at 34003350, 1929, 1090, 1050 cm-1 and 880 cm-1 were observed in the infrared region. The results appear to indicate that an interaction of the PO group of the phosphate esters possibly with the α-methylene group of the methyl linoleate molecule results in perturbation of the ir electrons of the double bonds of the latter. Therefore, a possible mechanism for the observed antioxidant activity of these esters involves either such an interaction or the formation of an unstable oil-soluble product as a result of such an interaction in early stages of autoxidation, rather than decomposition of hydroperoxides as has generally' been regarded for, the phosphate esters.

Since some of the phosphate esters derived by hydrolysis of Phosphatides have been found to show antioxidant activities in the dry unsaturated fatty acid esters, the authors examined whether they as well as some trialkyl esters of phosphoric acid show the activities in the water-unsaturated fatty acid ester system. Two techniques were employed : (1) Analytical grade filter paper was used for even distribution of the reactants, and increase in peroxide value (expressed as m mole of oxygen/100g substrate) with time was determined for examination of effects on pH. (2) The Warburg apparatus was employed for examination of optimum concentrations (in a range from 0.01 to 0.1%) for the phosphate esters at pH 7.8.In the case of 0.0006mM solution all the esters examined showed prooxidant activities instead of antioxidant at pH 4.0. On the other hand, at pH 5.5, glycerylphosphorylserine showed the strongest activity, followed by phosphorylcholine (PC). Glycerylphosphorylcholine (GPC) showed the activity comparable to that of glycerylphosphoric acid (GP), which is generally active in various fatty acid esters, whereas phosphorylethanolamine (PE) and glycerylphosphorylethanolamine (GPE) exhibited no antioxidant activity. At pH 0.6 the GPC was found to be strongly active among others such as PE, PC and β-GP. Contrary to the findings in the dry fatty acid ester system (unpublished work), the trimethyl and triethyl phosphates showed an antioxidant activity at pH 5.5, while tributyl phosphate was less strongly active. These results as well as those obtained in the alkaline pH probably indicate that the P=O and P-O- groups in the phosphates are also related to the antioxidant activity in addition to the P-OH groups as was formerly suggested.The following percentages may be taken as possible optimum concentrations in the water-methyl linoleate system; PG 0.03% or less in fresh or somewhat oxidized substrate, PE 0.03-0.04% in fresh, PC 0.03% in fresh, PGE 0.04% in fresh, and GPC 0.03-0.05% in either fresh or somewhat oxidized substrate.

Abstract Reduction of egg yolk lecithins with lithum aluminium hydride under the following reaction conditions resulted in release of choline in about 50% based on the total water-soluble phosphorus; mole ratios of lecithin: lithium aluminium hydride of 1 : 10 or 1 : 15 at 10–15°C for 60–120min. were used. Unexpectedly, the reaction did not give any glycerylphos-phoric acid. Instead, the analytical results indicated that a phosphorus-oxygen fission of the cholin-phosphate linkage is accompanied by reduction of the phosphate moiety.