THE ANALYSIS OF FAT CHARACTERISTICS OF 12 WALNUT CULTIVARS IN SHANXI PROVINCE

Walnut kernels contain abundant fat, and there is a large amount of planting area of walnut in Shanxi province where high-oil type cultivars are increasingly being focused on. To learn the fat characteristics of walnut cultivar kernels from Shanxi Province, 12 cultivars of walnut were analyzed for their oil content of the kernel and for their fatty acid composition by using the soxhlet extraction method and gas chromatography. A preliminary classification and comparison was made on the basis of the data. The results show that the oil content of different cultivars from the same region ranges from 59.4-71.5%, with an average of 65.9%, and ‘Xifu No.1’ was the highest at 71.5%. The value of unsaturated fatty acid averages 92.4%, and the ratio of unsaturated to saturated acid is 7.6:1. Among the different cultivars there existed differences in fatty acid composition. An oleic acid-rich cultivar was ‘Jinlong No.2’ (40.5%), a linoleic acid-rich cultivar was ‘Liaoning No.1’ (66.5%) and a linolenic acid-rich cultivar was ‘Xifu No.1’ (13.5%). The ratio of N-6:N-3 was closest to 4:1 in ‘Zhonglin No.1’ (4.6:1). The cultivars of walnut had different nutritional characteristics to meet specific requirements and can thus form special population groups. Some cultivars of low SFA value like ‘Beijing861’, ‘Jinlong No.2’ and ‘Zha343’ could become important export cultivars.