水酶法提取核桃油过程中不同破碎方式对核桃油品质的影响

该研究采取6种不同破碎方式处理核桃仁，采用水酶法提取核桃油。研究了不同破碎方式对核桃仁粒径、出油率、脂肪和蛋白残留量、核桃油酸价、过氧化值、脂肪酸组成和挥发性成分组成的影响。结果表明：经过无水研磨和两次三辊研磨后出油率为54%。核桃油D（无水研磨和两次三辊研磨）饱和脂肪酸相对含量升高，而不饱和脂肪酸含量降低。通过顶空固相微萃取-气质联用法分析核桃油挥发性组分，共检测到56种挥发性组分。通过聚类热图得知醛类、酯类和烃类相对占比高。综合来看，无水胶体磨和一次三辊研磨结合，可以实现核桃连续破碎，得到品质优良的核桃油。水酶法提取核桃油，需要降低物料粒径，同时减少破碎过程中的乳化作用。该研究可为水酶法提取核桃油提供支撑，为核桃油精准适度加工奠定基础。

Effects of Different Comminution Methods Used during Aqueous Enzymatic Extraction on the Quality of Walnut Oil

In this research, walnut kernel was processed by six types of comminution methods, and walnut oil was prepared by aqueous enzymatic extraction (AEE). The effects of different types of comminution methods on walnut kernel particle size, oil yield, residual protein and oil acid value, peroxide value, fatty acid composition and volatile composition were studied. The results show that the oil yield was 54% after anhydrous colloid grinding and two 3-roll grindings. Walnut oil D (anhydrous colloid grinding and two 3-roll gridings) had higher relative fatty acid content and lower unsaturated fat content. The volatile components of walnut oil were analyzed by headspace-solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). A total of 56 volatile components were identified. The relative high proportions of aldehydes, esters and hydrocarbons were revealed by the cluster heatmap. Taken together, the combination of anhydrous colloid grinding and one 3-roll grinding was better than other methods, allowing continuous crushing of walnut and the production of good quality walnut oil. The extraction of walnut oil by the aqueous enzymatic method requires the reduction of the particle size of raw material and the emulsification during crushing. This study provides a support for extracting walnut oil by aqueous enzymatic method and lay a foundation for accurate and moderate processing of walnut oil.