This work investigated the effect of freeze-thaw (FT) pretreatment on the yield and quality of oil cold-pressed from perilla seeds. FT pretreatment ruptured the perilla seed coat and internal structure, resulting in an oil yield of 78.71%, about 2.5-times greater than the yield from untreated control perilla seeds. Acid values were relatively low (0.54 mg KOH/g) and not different in the FT-treated and control oil. Likewise, peroxide values were low (1.34 meq/kg) and not different amongst the treatment groups. Viscosity values (96.5 mPa s) were indicative of a light oil while color values (L*a*b*) indicated a light yellow-green color. The major unsaturated fatty acids were identified as linolenic acid (C18:3, ω−3), linoleic acid (C18:2, ω−6), and oleic acid (C18:1, ω−9). The most abundant volatiles were 1-(furan-2-yl)-4-methylpentan-1-one and 3-(4-methyl-3-pentenyl)-furan in both of the oil samples. However, the normalized relative intensity of the volatile compounds was reduced in the FT-treated PO. The acylglycerol profile in FT-treated and control PO was not different, yet another indication that FT pretreatment did not increase oil rancidity or oxidative instability. FT pretreatment on oil seeds before cold-pressing is an attractive technique for obtaining high oil yield without deteriorative effects on the quality characteristics of edible oil.

这项工作研究了冻融（FT）预处理对紫苏种子冷榨油的产量和品质的影响。FT预处理破坏了紫苏种皮和内部结构，导致油收率为78.71％，比未处理的对照紫苏种子的收成高约2.5倍。酸值相对较低（0.54 mg KOH / g），在FT处理的油和对照油中无差异。同样，过氧化物值低（1.34meq / kg），并且在各治疗组之间没有差异。粘度值（96.5 mPa s）表示浅色油，而颜色值（L * a * b *）表示浅黄绿色。主要的不饱和脂肪酸被鉴定为亚麻酸（C18：3，ω-3），亚油酸（C18：2，ω-6）和油酸（C18：1，ω-9）。在两个油样中，最丰富的挥发物是1-（呋喃-2-基）-4-甲基戊基-1-酮和3-（4-甲基-3-戊烯基）-呋喃。但是，在FT处理的PO中，挥发性化合物的标准化相对强度降低了。FT处理和对照PO中的酰基甘油谱无差异，这又表明FT预处理不会增加油酸败度或氧化不稳定性。在冷压之前对油料种子进行FT预处理是一种吸引人的技术，可在不影响食用油质量特性的情况下获得高油产量。还有一个迹象表明，FT预处理不会增加油酸败度或氧化不稳定性。在冷压之前对油料种子进行FT预处理是一种吸引人的技术，可在不影响食用油质量特性的情况下获得高油产量。还有一个迹象表明，FT预处理不会增加油酸败度或氧化不稳定性。在冷压之前对油料种子进行FT预处理是一种吸引人的技术，可在不影响食用油质量特性的情况下获得高油产量。