| Abstrakt: |
Six rapeseed cultivars were chosen from three regions, including the upper, middle, and lower Yangtze River valley, and planted in Sichuan, Hubei, and Zhejiang experimental sites using the similar cultivation measures. The rapeseed was harvested at maturity stage, followed by cold pressing and the composition of unsaturated fatty acids (USFAs) and the content of chlorophyll, the total polar phenols, phytosterols, and tocopherols of rapeseed oil were assessed. Moreover, the essential properties of rapeseed oil on each experimental site were refined. The results showed that there were significant differences between the experimental sites in terms of the oil content and oil extraction efficiency of rapeseed, the chlorophyll, the total polar phenols, phytosterols, and tocopherol content of rapeseed oil. The results showed that: (1) Sichuan had a higher oil content than Hubei, whereas Zhejiang had the lowest oil content. The varieties from the middle and lower reaches of the Yangtze River were planted in Sichuan and their oil content increased, meanwhile Zhejiang had the highest seed oil extraction efficiency followed by Sichuan and Hubei. (2) The oleic acid content of rapeseed oil was the highest in Sichuan, followed by Zhejiang and Hubei; whereas the higher linoleic and linolenic acid contents were noted at the Hubei experimental site. Moreover, the total polar phenols and phy-tosterol content of rapeseed oil was the highest in the Sichuan followed by Hubei and Zhejiang; contrarily, the tocopherol content and color of rapeseed oil were best in the Zhejiang followed by Hubei and Sichuan. (3) Rapeseed oil's antioxidant capacity significantly varied between sites, which was the highest in Sichuan, followed by the Hubei and Zhejiang. The lower temperature and rainfall during rapeseed pod maturity period contributed to the stronger antioxidant capacity of studied cultivars in Sichuan site. Conclusively, the rapeseed oil quality was varied at different experimental sites in the Yangtze River valley. Thus, the findings of the current study can be used as a reference when choosing high-quality rapeseed varieties in different ecological zones. [ABSTRACT FROM AUTHOR] |
