초록
대두품종으로서 새알, 광교, 단엽을 온도별($10^{\circ}C,\;20^{\circ}C,\;30^{\circ}C,\;40^{\circ}C,\;50^{\circ}C$)로 침지과정중 침출액의 성분변화를 관찰하였다. 대두가 같은 무게의 수분량을 흡수한 시간은 $20^{\circ}C$에서 7.5시간, $50^{\circ}C$에서는 3.5시간이 걸렸다. 침지액의 pH변화는 온도가 상승할수록 낮아지는 경향을 보였다. 수용성 고형물의 함량변화는 침지 시간이 길수록, 온도가 상승할수록 많아져서 침지중 거의 직선적인 속도로 용출되었으며 24시간 침지 후 대두 100g당 $20^{\circ}C$에서는 $0.4{\sim}0.7g$정도, $50^{\circ}C$에서는 $10.2{\sim}15.0g$ 정도 용출되었다. 용출된 총 고형물 중 $12{\sim}25%$는 단백질이었으며 단백질 용출 비율은 침지 시간과 온도의 상승에 따라 증가했다. 24시간 침지 후 대두 100g당 $20^{\circ}C$에서는 80$\sim$200mg, $50^{\circ}C$에서는 $440{\sim}480mg$정도의 단백질이 용출되었다. 수용성 당의 용출은 24시간 침지 후 $20^{\circ}C$에서는 약 5%, $50^{\circ}C$에서 $83{\sim}100%$가 용출되었다. 그 중 sucrose, fructose, raffinose와 stachyose는 $20^{\circ}C$에서 24시간 침지 후 각각 3%, 3.8%, 2% 그리고 1%가, $50^{\circ}C$에서는 각각 87%, 150%, 80%, 77% 정도가 용출되어서 침지온도가 상승할수록 당의 용출량이 증가하였다.
Dried soybeans (varieties: Saeal, Kwanggyo, Tanyob) took up water rapidly for first 3hr followed by a slower rate of uptake. The beans took up an equal weight of water (100% hydration)after approximately 3.5hr at $50^{\circ}C$, 5hr at $30^{\circ}C$ and 7.5hr at $20^{\circ}C$ respectively. pH of the soaking solutions decreased during the soaking period. This was undoubtedly caused by the ionization of the cellular components resulting in increased levels of hydrogen ions in the liquor. Soluble solids were leached out of the beans at fairly steady rate throughout the hydration and the amount was greater with higher temperature. This amounted to 0.4-0.7g at $20^{\circ}C$ and 10.2-15.0g at $50^{\circ}C$ per 100g soybeans. Temperature was the most important factor in determining the rate of water absorption and of solid losses. Of the total solids lost, 12-25% was protein. The proportion of protein loss increased as the soaking time and temperature increase. Amount of protein loss was 80-200mg at $20^{\circ}C$ and 440-480mg at $50^{\circ}C$ after 24hr soaking per 100g soybeans. About 5% of soluble sugars, including fructose, sucrose, raffinose, and stachyose, was removed from the beans after 24hr soaking at $20^{\circ}C$.