Abstract
To improve the quality and increase the yield of thick bean sprouts, and to expand their usage, we cultivated thick mung bean and soybean sprouts by dipping intermittently in mixed phytohormone solution in combination with irradiation of artificial sunlight lamps (DPSL method). Concerning growth, the extension of the hypocotyl and the main root and the number of lateral roots were markedly inhibited in both types of bean sprouts. The hypocotyl was hypertrophied, and the hardness and the mastication degree increased, fulfilling the suitable qualities for marketing. Thus, the external appearance was improved. The surface color of the hypocotyl was pale yellow to light yellowish green in both types of thick bean sprouts. This color provided additional value such as their use for salads and other dishes as a colored vegetable. The moisture content was inadequate for both types of bean sprouts, resulting in lacking of juiciness. The yield was also insufficient for both types. Among the components, protein and sugar increased while fat decreased in both types of bean sprouts. With cultivation days, the content of water-soluble vitamin except VB1 increased in both types of bean sprouts. Though the VB1 content tended to decrease, its content was higher than that in the control. Chlorophyll was not present in either type of bean sprouts on day 1-2 of cultivation but was produced from day 3 and markedly increased with cultivation days. In mung bean sprouts, carotene was not present in the control and was produced from day 3 of cultivation. In soybean sprouts, a very small amount of carotene was present at the time of inoculation (germination). In both types of bean sprouts, the carotene content increased from day 3 of cultivation, but the degree of the increase was slight compared with chlorophyll. The DPSL method inhibited growth and improved the composition and external appearance. Application of artificial sunlight lamps induced color in the hypocotyl and increased the nutritional composition by producing chlorophyll and carotene. These changes improved quality, expanding their usage. However, the decrease in the yield due to the inadequate moisture content is economically disadvantageous. Furthsr studies on cultivation conditions are necessary
