The Study of Drying Condition for Local Dried Fermented Soy Bean (Thua Nao)

Abstract

This research aims to study an optimum drying condition for the semi-dried fermented soybean and further produce a seasoning rice flake with spicy flavor. Three drying temperatures of 120, 130 and 140°C were studied. The chemical and physical properties of the dried fermented sample soybean were analyzed and compared with a reference sample from a community product (Phrao district, Chiangmai province, Thailand). It was found that the chemical and physical properties of the sample dried at temperature of 130°C for 35 minutes was similar to that of the community product (Phrao district, Chiangmai provinve, Thailand). The lightness (L*) was 51.74±0.60, redness (a*) was 5.31±0.39 and yellowness (b*) was 20.35±1.09. The moisture content was 4.65±0.19% wet basis. The water activity (aw) was 0.26±0.02. The overall sensory acceptance was moderate (7.27±0.59). After that the dried fermented soy bean was used to develop the seasoning rice flake (spicy flavor). The recipe from the commercial product was applied with a ratio of 35 percentage of the dried fermented soybean flake. The sensory test on the seasoning rice flake was evaluated. It was found that the overall acceptance on the spicy flavors of seasoning rice flake from the panelists was moderate with the score of 7.44±1.01. 