Comparative Study on the Vitamin C Contents of the Food Legume Seeds

Abstract

SummaryWe found that dehydrated legume seeds (6 genera, 19 species and cultivated varieties) contained considerable amounts of vitamin C (VC). The average value of total VC content per 100 g of dry weight in dehydrated seeds varied from 0.24 mg (kidney beans) to 4.14 mg (green peas). Yard beans showed highest values among all legumes examined here in the both dehydrated and rehydrated forms (3.19 and 10.8 mg, respectively). By soaking for 16 h in the dark at 20˚C, total VC contents of black grams and mung beans increased to 3.1-and 4.5-fold, respectively. However, three varieties of green peas (Hakuryu, Kurumeyutaka, and Nankaimidori) significantly lost their VC during the same soaking treatment. Total VC content of a rehydrated and cooked mung beans was higher than that of a dehydrated form. Appreciable amounts of total VC were detected in the immature seeds of six different genera such as yard beans, kidney beans , broad beans , green peas, soybeans and peanuts. Except for mung beans, 70-100% of VC in dehydrated seeds of adzuki beans, broad beans, green peas, black soybeans, and soybeans was lost by boiling. Total VC and L -ascorbic acid in mung beans, green peas, broad beans, black soybeans, and adzuki beans remained even after boiling, suggesting that it is possible to obtain VC from the cooked forms of these legume seeds.

Achievements and Challenges in Improving the Nutritional Quality of Food Legumes

“…Nevertheless, the loss of vitamin C during the blanching of grass pea (Lathyrus sativus) seeds was approximately 30% (Korus et al, 2002). The high loss of total vitamin C (70% -100%) during boiling of adzuki beans, faba beans and peas was described by Moriyama and Oba (2008). This culinary process in grass pea and pea caused a 45% reduction in vitamin C content (Vanderslice et al, 1990;Korus et al, 2002).…”

“…However, due to its hydrophilic properties and strong reducing power, the amounts are important from a nutritional point of view. According to Moriyama and Oba (2008), the content of ascorbic acid in peas was positively correlated to the total antioxidant capacity of the water soluble compounds. The content of vitamin C in legume seeds is summarized in Table 6.…”

Legumes as a source of natural antioxidants

“…Additionally, there has been evidence to suggest that g-tocopherol may be protective against cardiovascular disease because plasma g-tocopherol levels were inversely associated with increased morbidity and mortality due to cardiovascular disease in population studies. Leguminous seeds are not a rich source of vitamin C [52], but this vitamin's contribution to the antioxidant capacity of seeds, especially for the part generated by hydrophilic compounds, is high. In foods of plant origin, vitamin C is determined as ascorbic and dehydroascorbic acid.…”

“…However, the varieties of green peas significantly lost their total vitamin C during the same soaking treatment. Boiling of dehydrated seeds of adzuki beans, broad beans, and green peas resulted in ,70-100% loss of total vitamin C [52]. The cooking of grass seeds reduced the content of vitamin C by 10 and 11%, depending on the cultivar, while the share of ascorbic acid fell to 45% in the amount of vitamin C [55].…”

Effect of Germination on Biochemical and Nutritional Quality of K wati

“…Dehydrated legume seeds reported to contain considerable amount of ascorbic acid, ranging from 0.24 mg/100 g in kidney beans to 4.14 mg/100 g in green peas (Moriyama and Oba ). Several studies have reported that germination leads to increase in antioxidant activity of which ascorbic acid is the main contributor (Lin and Lai ; Khattak et al .…”