As important oil crops in Inner Mongolia, sunflower, and flaxseed had distinct lipid profiles in seeds. As an emerging cash crop, Hibiscus manihot L. has strong potential market competitiveness. In this study, the lipidome, fatty acid composition and quality characteristics of flaxseed, H. manihot L., and sunflower seed oils were analyzed and compared. A total of 270 distinct lipids were identified and analyzed with an emerging detection approach-lipidomics, which illustrated the tremendous difference among the samples. triacylglycerol, diacylglycerol and polar lipids were the most abundant lipids in all samples. H. manihot L. seeds contained higher saturated and monounsaturated fatty acids and lower polyunsaturated fatty acids. H. manihot L. seed oil had the longest oxidative stability index time, high content of vitamin E and total phenolics, while flaxseed oil embodied the lowest oxidative stability. The peroxide value and acid value of the three oils were within the allowable range of Chinese national standards.

Hibiscus manihot L. seed oil is an emerging high-value edible vegetable oil that also has a variety of important health functions, and concerns about its pressing method have great significance for commercial and consumer health. This study compared triacylglycerols (TAGs), diacylglycerol (DAG), free fatty acids (FFAs), and volatile flavor compounds for discriminating cold-pressed oil from hot-pressed oil. The profiles of TAGs, DAGs, FFAs, and flavor compounds were established by a lipidomic approach and electronic-nose (E-nose). Our results demonstrated that a slight decrease in TAG content and a significant increase in FFA and DAG contents were observed after roasting. The E-nose results showed that sulfides, terpenes, methane, compounds containing oxygen and nitrogen, alcohol and aromatic compounds greatly influenced the oil flavor. The PCA result of the E-nose data indicated that flavor compounds showed great promise for distinguishing the two samples. The quality indices and the oxidative stability of oil samples were detected to identify their nutritional value and edible quality. This study revealed that roasting greatly influenced the lipid and flavor substances of the Hibiscus manihot L. seed oil. Our findings could provide useful information on the impact of the pressing method for Hibiscus manihot L. seed oil.