Development of Nutritious Soy Fortified Snack by Extrusion Cooking

Abstract

A nutritious soy fortified snack with good texture and good protein quality was achieved from formula 8 containing 18% of soy flour (9% DFS + 9% FFS) replaced in a blends of corn grit and broken rice, 2% soybean oil and fortified with a mixture of vitamins, minerals and amino acids. Mixed ingredients were adjusted to 16.5 ± 0.5% moisture content and fed at 365 g/ min to extrusion process at 165–167°C melt temperature employing Berstorff laboratory twin screw extruder operated at 300 rpm. The obtained snack had expansion ratio (ER), bulk density (BD) and compression force (CF) of 3.9, 58 g/L and 60.17 N, respectively and was subsequently sensory evaluated (9-point hedonic scale) for preference and acceptance together with control samples and popular market snacks. Snack sample from formula 8 had gained the highest score in color, flavor, texture and overall acceptability (P ≤ 0.05). Protein content in the developed snack sample is 9.9% which was 46.67–70.69% higher than in the market snacks. Furthermore, there was also a greater quantity of lysine and methionine plus cystine and all those essential amino acids were accounted for at least 80% of the FAO/WHO (1973) recommendation. It also exhibited as a good source of vitamin B₆, B₂, calcium and sodium, and also rich in B₁₂ and iodine. In addition, ratio of calories gained from carbohydrate, protein, fat from the snack was almost equal to Thai-RDI. Thus, the developed soy fortified snack could be regarded as a palatable and nutritious snack.