Effect of Cooling Methods and Drying Temperatures on the Resistant Starch Content and Acceptability of Dried-Growol

Growol is a local staple food made from cassava that is processed by spontaneous fermentation in water for 3-5 days. Previous research has shown that drying Growol could extend its shelf life, and fermentation during processing could increase the amylose content. Increasing the amylose would produce high retrograded starch, which is a resistant starch (RS). The aim of this study was to evaluate the effects of different cooling methods and drying temperatures on the amylose content, the resistant starch content and the acceptability of dried-Growol. Materials and Methods: The cassava used in this research was the Martapura variety, which was fermented for 24 h and cooked by use of an autoclave for 15 min. Samples were then either cooled to room temperature with no subsequent storage or stored in a refrigerator at 4-7°C for 24 h and then dried with temperature variations of 40, 50 and 60°C. The dried Growol samples were analyzed for their moisture content, starch, amylose, X-ray diffraction, resistant starch content and their acceptability by hedonic test. Results: The research showed that varying the cooling method and drying temperature affected the amylose and RS content, and the acceptability of dried Growol. Cooling at refrigerator resulted dried-Growol with high RS and acceptability. Conclusion: Acceptable dried-Growol was obtained by cooling by refrigeration and drying at temperatures of 50-60°C. This Growol had an amylose content of 42.92-44.63%, the degree of crystallinity was 25.81-26.16% and it had an RS content of 16.55-17.04 g/100 dry matter.
keyword Amylose, fermented-cassava,Growol, Resistant-strach, retrogradation