Abstract This study investigated the effect of addition of hydrocolloids (hydroxypropyl methylcellulose: HPMC, and xanthan) and frozen storage on the structure and rheological properties of frozen roti dough supplemented with rice bran. The roti dough was frozen by air blast freezing and stored at -18 °C for 84 days. Changes in the protein structure of the frozen roti dough with HPMC produced greater changes in the gluten network and random coil conformations than that of the xanthan supplemented dough during frozen storage. The resistance to extension and the elastic modulus of the frozen roti dough with HPMC tended to decrease while the extensibility slightly increased with a longer frozen storage time. However, these parameters did not change in the frozen roti dough with xanthan. The freezable water in the frozen roti dough with HPMC and xanthan significantly increased (p < 0.05) with increasing frozen storage time from 0 to 84 days.

Abstract The functional properties, resistant starch (RS), and glycemic index (GI) of fresh noodles substituted with banana flour (BF) were investigated. When the substitution with BF was increased from 0 to 40%, the viscoelastic properties increased, while tensile strength and elasticity decreased from 53.23 to 26.84 gf and 44.65 to 15.04 mm, respectively. GI was reduced from 77.05 to 62.62 while RS content increased from 5.56 to 23.31%. This is considered a very high RS content and the modified noodles are classified as intermediate GI food. Furthermore, the effects of xanthan gum (XG), guar gum (GG), and carboxymethyl cellulose (CMC) individually at 1.0% and 1.5% levels on quality of dried noodles substituted with 30% BF (DBF30) were investigated. DBF30 with XG had the shortest rehydration time (6.5 min), while DBF30 with CMC had the slowest rehydration (8.5 min). The added hydrocolloids increased rehydration and decreased the cooking loss of DBF30, also increasing tensile strength and elasticity of DBF30. Furthermore, the hydrocolloids increased RS content and reduced GI of DBF30. The results reveal that adding BF and hydrocolloids to noodle products provides high nutritional quality with enhanced quality characteristics.