オホーツク網走産ナガイモより調製した澱粉の特性評価

We evaluated the characteristic of nagaimo (Chinese yam) starch produced in Abashiri Okhotsk. The result of characterization showed that a nagaimo starch grain had a smooth, spherical shape like a potato starch grain. The average diameter of the nagaimo starch grain was 22.7μm, somewhat smaller than that of potato starch grain (24.1μm). The gelatinization start temperature for the nagaimo starch was 72.5℃, lower than that for potato and tapioca starch (69.4℃ and 70.9℃, respectively). The viscosity of the nagaimo starch increased to only half of that of the potato starch, even after swelling by the addition of water and heat. The tendency of the nagaimo starch grain toward breakdown was second highest next to that of the potato starch grain, and the tendency toward aging (set back) was second highest next to the tapioca starch. Bolo cookies made from the nagaimo starch had moderate hardness and good solubility in the mouth. This finding suggests that the nagaimo starch would be a prospective raw material for bolo production.