Influence of different concentrations of alcoholic-alkaline modified enset starch as the stabilizing agent on low-fat set yogurt quality

Abstract

The aim of this study was to evaluate the effect of alcohol-alkaline modified enset starch on the quality of low-fat set yogurt. This study employed factorial design with stabilizer percentage having three levels (1%, 2%, and 3%) and stabilizer type with three levels (Native Enset Starch (NES), Modified Enset Starch (MES) using alcohol-alkaline treatment, and Corn Starch (CS)). The developed yogurt was stored in refrigerator (5°C) and the physicochemical, microbial and sensory properties were evaluated on the 1st, 7th, and 14th days of storage. The low-fat set yogurt with 3% MES showed a pH, total soluble solids, and titratable acidity of 5.00, 18.00 °Brix, and 0.41% on the 1st day, 4.52; 17.93 °Brix and 0.44% on the 7th day; and 4.31, 17.05 °Brix and 0.50% on the 14th days, respectively. The low-fat yogurt with 3% MES had the lowest syneresis (6.05%), while the control yogurt had the highest syneresis (10.05%). Yogurt sample with 3% of CS had the highest L* value (89.01) while the yogurt with 3% MES had the lowest (78.85). Yogurt with 3% MES had the highest viscosity (387.9 mPa s), whereas the control had the lowest viscosity (245.6 mPa s). The highest colony forming units (5.65 × 103 CFU/mL) was detected in the yogurt sample with 2% MES, while the lowest (1.55 × 103 CFU/mL) was found in the control yogurt samples. Therefore, for the optimum physicochemical, functional, sensory and microbial properties, 3% MES is recommended as suitable stabilizer to use in the low-fat set yogurt.

Keywords

• Alcoholic-alkaline treatment
• low-fat set yogurt
• Rheology
• stabilizer
• modified enset starch