Effect of xanthan gum/CMC on bread quality made from Hom Nil rice flour

Hom Nil rice is widely grown in the Northern of Thailand. It has tapering shape, dark purple color, soften texture after cooking and also good smell. Nowadays, there was an increasing interest for gluten-free products as the number of the celiac patient grows. Many researchers have been attempted to use rice flour to substitute wheat flour in bread. However, almost rice flour proteins have poor functional properties because it has no glutenin and gliadin to form gluten that giving a dough appearance and final quality. From previous researches were used hydrocolloids to improve characteristic of bread made from rice flour. Therfore, the objective of this study was to study the effect of xanthan gum and carboxymethylcellulose (CMC) on bread quality made from Hom Nil rice flour (HNRF). The results showed that moisture content, protein, ash, fat, carbohydrate and crude fiber content of the HNRF were 8.40%, 7.71%, 1.71%, 4.11%, 78.06% and 1.42%, respectively. The pasting temperature, trough, breakdown, final viscosity, peak viscosity, peak time and set back of HNRF were 86.28o C, 1074 cP, 254 cP, 2207 cP, 1327 cP, 5.8 mins and 1133.5 cP, respectively. HNRF was used to produce bread with varied xanthan gum and CMC in ratios of 3:0, 2:1, 1.5:1.5, 1:2 and 0:3 respectively. The results showed that the ratio of xanthan gum and CMC at 1:2 provided the higher acceptable liking score than others (p?0.05). The appearance, odor, softness, and overall acceptance of bread were 6.37, 6.03, 6.03, and 6.10 respectively. Moisture content, protein, ash, fat, carbohydrate and crude fiber content were 30.16%, 6.74%, 2.12%, 6.88%, 54.10% and 1.36%, respectively. Hardness, springiness and chewiness of the Hom Nil bread were 7.02 g, 0.73 mm and 1.81 gmm respectively