Effect of germination on the thiamine, riboflavin and niacin contents in legumes

Abstract

The effect of germination on the thiamine, riboflavin, as well as the available and total niacin contents in two varieties of lentils (Lens culinaris, var. vulgaris, Lens culinaris, var. variabilis) and faba beans (Vicia faba, L., var. major) were investigated. Germination of the three legumes, carried out for 6 days at 20 °C in the dark and with daily rinsing, led to a significant reduction of the thiamine content and a significant increase of the riboflavin as well as the total and available niacin contents. For Lens culinaris, var. vulgaris the effect of different conditions during the germination procedure (light, time and number of rinses) on water-soluble vitamins was studied. The presence or absence of light had no significant effect on the thiamine and riboflavin contents in germinated lentils, while the niacin content was higher when germination was conducted in the light. The increased number of rinses during the germination process had no significant effect on the thiamine content in lentils, whereas a significant decrease in the riboflavin and available niacin contents was observed, except for riboflavin when germination was carried out for 6 days and for available niacin when germination was carried out for 3 days without light, where no significant changes were detected. A longer germination time led to a recovery of the decrease in the thiamine content that was observed to occur during the initial period of germination, and significant increases of the riboflavin and available niacin contents in lentils, independently of other conditions (light and number of daily rinses), were observed. When germination was carried out for 10 days in the dark and with daily rinsing, maximal increases of the riboflavin and available niacin contents with minimal decreases in the thiamine content were observed.