The study of functional and pasting properties of Taro “SEMIR” (Colocasia Esculenta L. Schott) starch modified by various thermal process

Abstract

Taro tubers locally known as Semir are potentially used as a source of starch. Taro Semir starch can be used as a substitute of rice flour in the raw material of rice vermicelli. However, native taro starch has not been optimally utilized due to poor functional and poor pasting properties. Thus, further treatment is needed to improve their properties. The ideal characteristics of starch as a raw material of vermicelli are low swelling volume, stable against heating and stirring, and fast-rising value of setback viscosity. The aim of this research was to determine a suitable physical modification to produce functional and pasting properties of taro Semir starch. The physical modifications were applied in preparing taro Semir starch includes Heat Moisture Treatment (HMT) at 110°C for 8 hours, Heat Pressure Treatment (HPT) at 120°C 1 hour, Microwave Heat/Moisture Treatment (MWT) with 100W 20 minutes, and Osmotic Pressure Treatment (OPT) at 120°C 30 minutes. Those modified taro Semir starch were compared with the native taro Semir starch. Taro Semir starch modified by HMT revealed with the best performance compared to others modification. The obtained characteristic of this starch were swelling volume of 6.57±0.80 mL/g, solubility of 5.80±0.29 %, water absorption capacity of 2.59±0.09 g/g, gel strength of 3,518±0.17 gF, syneresis percentage of 5.39±2.31 %, pasting temperature of 83.65±0.77°C, peak viscosity 4,349.17±192.61 cP, breakdown viscosity 494±33.81 cP, and setback viscosity of 2,413±165.85 cP. It was concluded that HMT at 110°C for 8 hours considered as the best method of modification for the Taro Semir starch.