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The lipids extracted from beef and pork muscle were fractionated into triglycerides, cephalins, and a mixture of lecithins and sphingomyelins. The fatty acid composition of these fractions was determined, and the possible effect of phospolipids on meat flavor was evaluated.Cold-water extracts of lean beef and lean pork contain desirable meat-flavor precursors. These extracts do not, however, contain any appreciable proportion of the lipids present in the lean meat. Lipids, particularly the phospholipids, are among the more unstable constituents of lean meat; and Younathan and Watts (1960) have recently suggested that the phospholipids play a major role in accelerating flavor deterioration in cooked meats. This paper is concerned with the effect on flavor of the lipids present in lean meat prior to preparation for consumption. Our studies have therefore been made on aged lean beef and lean pork. The meat tissue lipids have been separated into neutral lipids and phospholipids, the fatty acids present in these fractions determined, and the possible contribution of these fractions to either desirable or undesirable flavor evaluated. EXPERIMENTAL Extraction of lipids from muscle. As in previous flavor studies (Hornstein and Crowe, 1960; Hornstein et al., 196Ob), fresh meat 'was aged 10 days at 36-38°F. Several of the muscles were then dissected and stored at 0°F.As needed, samples of meat were thawed, fat was removed, and the trimmed muscle was cut into small sections. The extraction procedure was essentially that of Folch et al. (1957). One hundred grams of the diced meat were blended for 5 min with 900 ml of cold 2:l chloroform-methanol (all solvents are reagent grade and all solvent ratios are v/v) in an Oster blender (mention of trade names is for identification and implies no endorsement). The slurry was immediately filtered, then mixed with 0.2 its volume of water in a Z-L separatory funnel, and allowed to stand overnight at >S"C. The separation into two phases was clean-cut. The lower phase was drained and, without further washing, dried over anhydrous sodium sulfate, concentrated to a small volume on a rotary evaporator at room temperature under partial vacuum, quantitatively transferred with several ml of chloroform to a tared 125-ml Erlenmeyer flask, and dried on the rotary evaporator.Residual solvent was removed under high vacuum. The weighed residue was redissolved in 20 ml of 2O:l chloroform-methanol.Small amounts of undissolved material were removed by centrifugation. Separationof neutral fat from phospholipids by column chromatography.Fifty grams of silicic acid (Mallinckrodt AR loo-mesh) heated overnight at 130°C were slurried with chloroform and poured into a 2.5 X 90-cm column fitted with a sintered-glass disc. Air bubbles were removed by stirring the mixture with a long glass rod. The silicic acid was allowed to settle and the chloroform drained under slight nitrogen pressure. When the column was compact and with at least 15 cm of liquid above the interface, anhydrous sodium sulfate was added to f...

Diminuition of the fat reserve and concomitant increase of carbohydrate during germination of oil seeds have been well established (3, 7, 10, 11, 12, 13,16). Few studies, however, have compared illuminated and unilluminated seedlings, or have controlled the environmental conditions to the degree necessary for calculation of a rate constant and for prediction of fat content at various stages of growth. MacLachlan (9) found a greater utilization of fat during soybean germination in the light than in the dark. He concluded that there was no preferential utilization of unsatuirated fatty acids, because no change was observed in the average unsaturation of the fatty acids in the cotyledons. But Holman (6), also using soybeans , reported a decrease in the iodine value of the fat reserve and a preferential utilization of linoleic and linolenic acid. Crombie and Comber (2) found that during the germination of seeds of the watermelon (Citruillus vulgaris) all the major fatty acids, except oleic, disappeared at rates proportional to the quantities present in the seed fat. Oleic acid was metabolized relativelv faster than the other fatty acids. A better understanding of the relations of fats to general metabolism may be expectedI to result from quantitative physiological and chemical studies of germinating fatty seeds. The extent to which reserve fats and current photosynthate contribute to the material and energy requirements for seedling growth represents one aspect of the broad problem. There is also a need for more analytical data on the changes that occur in the fatty acid composition of the glycerides as the fat reserve is utilized. The experiments reported in this paper were un-dertaken to study the rate of utilization and the composition of the fat reserve during cotton seed germination under various growth condlitions. To correlate the decrease in fat content with the growth of the seedlings, measurements were made of the development of the root, hypoeotyl, and cotyledon. MIATERIALS AND METHODS Cotton seeds of the 1953 crop (Gossypium hirsu-tum L., var. Fox, kindly supplied by the Delta and Pine Land Co. of Scott, M\iss.) were reduced in moisture to 6 % by drying with calcium oxide and then stored in sealed metal containers at 10 C (18). Small lots of seed were delinted in sulfuric acid for three minutes, rinsed thoroughly, soaked for 30 minutes in distilled water, and then allowed to germinate in the dark at 30 ± 10 C on wet filter paper. After 22 hours the seedlings with roots 7 to 12 mm long were supported on a layer of bobbinet (cloth netting with hexagonal mesh 3 by 3 mm) stretched over a glass rod frame provided with 4-cm legs. The frame was placed in a Pyrex dish which was filled to the level of the bobbinet with a culture solution having the following composition: 0.0040 M Ca (NO3)2 .4 H,0, 0.0030 M KNO3, 0.0016 M MgSO4 7 H20, 0.0012 I KH2PO4, 0.0005 M (NH4)2SO4, 0.00004 I FeCl2 4 H20, 0.00002 M K3C;H507 HaO (potas-sium citrate), and the following amounts in parts per million, of the microtrophic elements:...

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