Cooking Properties Sen, a Traditional Foodstuff of the Tsushima Island

Abstract

We examined the gelatinisation, paste texture, and gel rupture properties of the fermented sweet potato product ‘Sen’, a traditional foodstuff of the Tsushima Island, in comparison with that of the sweet potato powder and sweet potato starch.
Based on the chemical composition, starch was the most abundant component in Sen as well as in sweet potato powder and sweet potato starch. The contents of soluble and insoluble dietary fibres were 0.9%, 1.8% in Sen and 3.0%, 5.7% in sweet potato powder, respectively. The onset, peak, and termination temperatures for Sen gelatinisation were 65.3°C, 72.5°C, and 80.2°C, respectively. The gelatinisation properties of Sen were similar to those of sweet potato starch. The paste texture tests, with concentrations ranging from 1-12%, revealed that both the hardness and adhesiveness of Sen paste were relatively higher than those of the other two samples. Moreover, the gel rupture tests demonstrated that the Sen gel was harder and more elastic than the sweet potato powder gel. The rupture properties of Sen gel and sweet potato starch gel were similar.