Effect of germination pretreatment on the physicochemical properties and lipid concomitants of flaxseed oil

This study investigated the effects of germination pretreatment on the physicochemical properties, lipid concomitants, and antioxidant activity of flaxseed oil in three varieties. The results indicated that the oil content of flaxseed decreased by 2.29-7.40% during the 5 days germination period. Germinated flaxseed oil showed a significantly higher acid value and lower peroxide value. The unsaturated fatty acid content was slightly increased by germination. Germination pretreatment resulted in significant increases in the alpha-tocopherol, stigmasterol, pigments, total phenols, and antioxidant activity. As germination time progressed to 5 days, alpha-tocopherol which was traditionally recognized as having the highest antioxidant activity form of vitamin E in humans increased from 3.07-6.82 mg kg(-1) to 258.11-389.78 mg kg(-1). Germinated oil had 1.63 to 2.05 times higher stigmasterol content than non-germinated oil. The chlorophyll and carotenoid also increased exponentially. The total phenol content of flaxseed oil increased from 64.29-75.85 mg kg(-1) to 236.30-297.78 mg kg(-1). Germinated flaxseed oil showed important antioxidant activity. Compared with other varieties during germination, the oil from Gansu showed a higher level of alpha-linolenic acid, tocopherols, and carotenoid, and a maximum increase level of tocopherols and phytosterols. The comprehensive evaluation of germination time by correlation and principal component analysis showed that when germination time exceeded 2 days, the lipid concomitants and antioxidant capacity of flaxseed oil were significantly improved.

Automated summary

This study explored the effects of germination pretreatment on the properties and antioxidant activity of flaxseed oil. Results showed that germination increased the unsaturated fatty acid content and antioxidant activity of the oil. Alpha-tocopherol, stigmasterol, pigments, and total phenols also increased significantly with germination. The longer the germination time, the higher the levels of these compounds, indicating improved lipid concomitants and antioxidant capacity of flaxseed oil.