根莖澱粉의 調理性에 關한 硏究 - 生薑澱粉의 性狀을 中心으로 -

A Study on the Cooking Quality of Starch of Rhizome - Chiefly Centered on the Properties of Gelatinization of Ginger Starch -

Starch has been regarded as one of the useful foods of mankind, and in Chinese foods main ingregients of sauce have been made from the unique viscosity of gelatinized starch. Here, several kinds of starches of rhizome such as ginger starch, potato starch, sweetpotato starch and arrowroot, were chosen carefully. The experiments and comparisons were carried out to investigate whether they suitable for sauce ingregients or not. The methods used in the experiments were as follows; (1) measuring and comparing the viscosity of each starch by means of a Brabender Amylograph - 6% thich starch liquid - and measuring The change of viscosity by adding sugar, salt and vinegar to each starch; (2) measuring the texture of gelatine by using a Rheometer - 18% thick starch liquid; (3) measuring melting degrees of starch granules by using an Auto melt-pointer; (4) comparing colors of gelatinized starches by using a Digital color-meter of Richard S. Hunter. The results are summarized as follows; (1) Ginger starch begins to gelatinize at 86.5℃. The viscosity of ginger starch is increased in proportion to added sugar, and decreased in proportion to added acid. (2) Gelatine of ginger starch is apt to harden due to its own poor preservation ability. (3) The shapes of ginger starch granules are similiar to those of potato starch granules; they are oval. But diameter of potato starch granule is two or three times as long as that ginger starch granule. (4) Ginger starch begins to expand at 64℃ and to gelatinize slowly, while potato starch to melt rapidly at 64℃. (5) Gelatines of potato starch, arrowroot and ginger starch are clean and transparentness. and gelatine of sweetpotato starch has a turbid color.