Physicochemical Properties and Minor Lipid Components of Soybean Germ

Abstract

AbstractThis study aimed to determine and to compare the main phytochemicals from soybean and soybean germ of different Chinese varieties. The results indicate that the soybean germ contains low protein (38.19 %), lipids (10.98 %), and crude fiber (7.47 %) compared with soybean. Specific gravity, refractive index, and saponification values of soybean germ oil were comparable to those of soybean oil. However, unsaponifiable matter of the germ oil was significantly higher (6.982 %) than soybean oil (1.072 %). The tocopherol contents in soybean germ oil ranged as follows: γ‐tocopherol, 176.39 mg/100 g oil; δ‐tocopherol, 57.29 mg/100 g oil; α‐tocopherol, 50.67 mg/100 g oil; and β‐tocopherol, 8.15 mg/100 g oil. The main sterols in soy germ oil were β‐sitosterol (1,681.90 mg/100 g oil), crevesterol (358.02 mg/100 g oil), stigmasterol (189.62 mg/100 g oil), and brassicasterol (3.70 mg/100 g oil). Furthermore, soybean germ oil seemed to be an important source of triglyceride, fatty acids, and particularly the fatty acids in the sn‐2 position of triacylglycerol. The important nutritional value of all these phytochemicals makes soybean germ and particularly germ oil sources of functional molecules and additives for the food industry.