Kernel fatty acid and triacylglycerol composition for three almond cultivars during maturation

The kernel oil content, kernel FA and TAG composition, kernel moisture content, and kernel weight as well as fruit weight of three almond cultivars (Achaak, Mazetto, and Perlees) were monitored during the maturation of kernels. Lipid fractions of all almond samples were extracted using a mixture of chloroform and methanol. FAME and TAG contained in these fractions were analyzed by GC and HPLC, respectively. The ratio of kernel to fruit weight appears to be a good indicator of almond kernel development. The total lipid content of developing almond kernels exhibited a sigmoidal pattern with time, similar to seeds and kernels of other higher plants; the cultivar Achaak showed a higher rate of lipid accumulation. The proportion of oleic acid (0) dominated at the later stage of maturation for all three almond cultivars. Although there was no significant difference in the FA composition for the three cultivars studied, marked differences were observed in their TAG profiles. Ten TAG species identified were LLL, LLO, LnOO, LOO, LOP, PLP, OOO, POO, POP, and SOO, where L represents linoleic acid; Ln, linolenic acid; P, palmitic acid; and S, stearic acid. The difference in the TAG profile can be useful for distinguishing various cultivars. The oil of Mazetto cultivar kernels exhibited a TAG composition comparable to that of olive oil.