Sucrose content in soybean seeds is desired to be high because as a sweetness-imparting component, it helps in wider acceptance of soy-derived food products. Conversely, galactosyl derivatives of sucrose, that is, raffinose and stachyose, which are flatulence-inducing components, need to be in low concentration in soybean seeds not only for augmenting utilization of the crop in food uses but also for delivering soy meal with improved metabolizable energy for monogastric animals. In the present study, analysis of 148 soybean genotypes for sucrose and total raffinose family oligosaccharides (RFOs) contents revealed a higher variation (4.80-fold) for sucrose than for RFOs content (2.63-fold). High-performance liquid chromatography analyses revealed ranges of 0.64-2.53 and 2.09-7.1 mmol/100 g for raffinose and stachyose contents, respectively. As information concerning the environmental effects on the sucrose and RFOs content in soybean seeds is not available, we also investigated a set of seven genotypes raised at widely different geographical locations for these quality traits. Sucrose content was found to be significantly higher at cooler location (Palampur); however, differences observed for raffinose and stachyose contents across the growing locations were genotype-dependent. The results suggest that soybean genotypes grown at cooler locations may be better suited for processing soy food products with improved taste and flavor.

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Vegetable soybean is fast becoming a popular nutritious snack outside SouthEastern countries where its consumption is in vogue since ages. Reports have appeared in the literature concerning the nutritional value of green seeds; however, the information on its antioxidative properties is lacking. In the present investigation, 16 vegetable-type soybeans were evaluated for antioxidant constituents and antioxidative properties at picking stage. Vitamin C, total phenolic content, and total isoflavone were significantly different among different genotypes with ranges of 34.8-88.7 mg/100 g seed, 0.68-1.39 mg gallic acid equivalent/g, and 8.6-33.2 mg/100 g, respectively. 'Dada-cha 2000' had the highest total isoflavone followed by 'ASG328 Sricanan'. Genotypic differences were also observed for antioxidative properties viz. ferric reducing antioxidative power, free radical-scavenging activities, and β-carotene bleaching inhibition. 'Dada-cha 2000' showed the highest ferric reducing antioxidative power value (10.9μmoles/g), while 'Kegone' showed the lowest (3.95μmoles/g). 'Dada-cha ma-me', 'Dada-cha 2000', 'ASG328 Sricanan', and 'ASG328 Kohine' exhibited the highest free radical-scavenging activities. 'AGS439' and 'Dada-cha ma-me' exhibited the highest values for β-carotene bleaching inhibition followed by 'ASG328 Sricanan'. Correlation studies revealed significant positive correlation of ferric reducing antioxidative power and free radical-scavenging activities with individual forms of isoflavones and total isoflavone content.