ヤシ油配合脂肪の冷蔵中における劣化

抄録

Storage tests were carried out on commercial confectioner's fat containing coconut oil, at-20, 5 and 30°C for 12 months. while the confectioner's fat stared at-20 and 30°C showed no anychange during the 12 months, that stored at 5°C became rancid in 23 months and its acid valueincreased.
1) Samples stored at 5°C began to generate peculiar rancid odor characteristic of coconut oil after about 2 months and the acid value increased. This rancidity became stronger with increasingcontent of coconut oil and with increasing degree of hydrogenation.
2) There was no change in P.O.V. and the Co.V. was higher inthe samples stored at 30°C.
3) Acidity of the distillate from steam distillation of the samples stored at 30°C was almostthe same as that of the original sample, but that from the sample at 5°C was distinctly higher and the distillate did not contain oily matter which suggests the presence of a lower acid. Therefore, the distillate from vacuum distllation of samples stored at 5°C was examined by gas chromatographicanalysis and the products detected were C₄, C₆, C₈ and C₁₀ acids, with the largest amount far C₄acid, This fact suggests that the rancid odor is due mainly to these acid.