Presence of Endopeptidase in the Powdered Yam Dioscorea opposita and Its Effect on the Texture of Kamaboko

抄録

Yam is often added to kamaboko, such as Hanpen and Shinjo. We investigated the presence of endopeptidase in powdered yam and the effect of its addition on the texture of kamaboko. Hydrolyzing activities of casein and myofibrillar protein were observed in a crude extract of powdered yam. In addition, the optimum temperature and pH against casein and myofibrillar protein were approximately 70℃ and 7.4, and 60℃ and 6.8, respectively. Approximately 60% of the endopeptidase activity remained even with 3% NaCl. In the kamaboko to which powdered yam had been added degradation of the myosine heavy chain and decrease of the elasticity were observed.