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Dissociation of 5% solutions of calcium soaps of soya, tallow, stearic acid, and palm fatty acid distillate was studied by titration with 1 N HCl. Release of calcium ions was directly correlated with decrease in pH value. Estimated pKa values were 5.6, 4.6, 4.5, and 4.5 for calcium soaps of soya, palm fatty acid distillate, tallow, and stearic acid, respectively. Dissociation of 5% solutions in acetate buffer at pH values of 5.0, 5.5, 6.0, and 6.5 was measured in terms of release of soluble calcium. Dissociation was maximum at pH 5.0, minimum at pH 6.5, and dependent on unsaturation of fatty acids in the soaps. Soluble calcium in the acetate-buffered rumen fluid was higher than predicted from pKa of calcium soaps, due to formation of soluble calcium acetate; however, the relative patterns were similar to their pKa values. Unsaturated soaps are less satisfactory for maintaining normal rumen function, because dissociation is relatively higher. Calcium soaps of palm fatty acid distillate were satisfactorily stable to pH 5.5.

Fruit and kernel weights of developing almond kernels increased with age. The kernel contents had a translucent and jelly‐like appearance in the initial developmental stages, but solidified prior to the accumulation of dry matter, mainly oil, from 50 days after fertilisation (DAF). During kernel development the oil content displayed a double sigmoid pattern. Oleic and linoleic acids accumulated to similar levels, but the linolenic acid content decreased during development. Oil‐filling ([1‐14C]acetate incorporation) commenced at 50 DAF, and reached a maximum level at 70 DAF. The total polar lipid content was highest at 10 DAF, as determined by radioactive labelling, but from 30 DAF onwards a de‐novo synthesis was noted. Diphosphatidyl glycerol (Cardiolipin) acted as a temporary reservoir for the synthesis of phospholipids from 70 DAF, and thereafter the synthesis of phosphatidyl choline was enhanced. In the initial stages, the rate of synthesis of monogalactosyl diglycerides was greater than that of digalactosyl diglycerides, and a de‐novo synthesis of both was observed from 30 DAF. The synthesis of triacylglycerols corresponded well with the pattern of oil‐filling. The level of 14C radioactivity recorded in sterol esters was greater at the initial stages, but declined from 50 DAF, possibly because of the effect of dilution, as envisaged in the case of the triacylglycerols.

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In developing seeds of mustard (Brassica juncea L. cv. RLM 198) the period between 20 and 30 days after fertilization (DAF) was identified as the period of active lipid biosynthesis, although dry matter continued to accumulate until maturity. The period of lipid synthesis was associated with a decrease in starch, soluble sugars and protein, thus, giving rise to precursors for the biosynthesis of lipids. Besides decreasing the dry matter content (on both % and seed basis), Zn and S deficiency caused a significant (P > 0.05) reduction in oil content. As compared to control, the decrease in oil content was 11, 12 and 18% at 30 DAF and 4, 9 and 16% at maturity in Zn, S and (Zn+S) deficient treatments, respectively. Throughout the period of seed development, a significant decrease in starch and protein with a slight accumulation of soluble sugars was observed due to deficiency of Zn or S. The rate of [l‐14C]‐acetate incorporation into total lipids, which was maximal at 30 DAF, also displayed a significant decrease due to the abovementioned mineral deficiencies. Addition of Zn or S in vitro, enhanced the lipid synthesis at all stages of seed development. Under Zn and S deficiency, the phospholipids increased from 10 to 30 DAF and then declined until maturity. However, the proportion of glycolipids and free fatty acids increased, with a corresponding decrease in total glycerides. Further, in deficiency treatments, there was an increase in 22:1 with a corresponding decrease in 18:1, 18:2 and 18:3 in developing and mature mustard seeds.