Characteristics of dried noodle analogue made from sorghum flour and rice flour added with konjac glucomannan

The high popularity of wheat-based food such as noodles in Indonesia has caused a large increase in wheat imports. Sorghum and rice are two local ingredients found in Indonesia; however, sorghum is not largely used as the main grain source, especially in noodle making. This research aimed to determine the effect of the ratio between sorghum flour and rice flour, and konjac glucomannan concentration on noodle analogue characteristics. Konjac glucomannan was added at different concentrations (3%, 4%, 5%) to different ratios of sorghum-rice flours (50:50, 25:75, 0:100). Results showed that the best formulation was a noodle analogue made with a 25:75 sorghum-rice flour ratio and 4% konjac glucomannan. The best-formulated noodle analogue had a higher moisture content (13.35±0.38%), higher fat, and higher carbohydrate (71.93±0.11%), but lower protein and ash content than the commercial wheat-based noodle. It also had a lower starch (60.43%) and dietary fibre content (10.34%), higher cooking loss (9.44±0.60%), and lower water absorption (176.45±4.86%) compared to commercial wheat-based noodle. In terms of textural and mechanical properties, the best-formulated noodle analogue had lower hardness, higher adhesiveness, lower springiness, lower cohesiveness, lower tensile strength, and lower elongation. However, the multiple comparison test showed that panellists perceived the best-formulated noodle analogue to be comparable to commercial wheat-based noodle, in terms of aroma, chewiness, hardness, and adhesiveness.