Physicochemical and microbial stability of wheat bread as influenced by the supplementation of radiofrequency stabilized rice bran

The present study was aimed to assess the suitability of radiofrequency- treated rice bran supplementation in wheat bread. The refined wheat flour was blended with radiofrequency stabilized rice bran in varying proportions (100:0, 95:5, 90:10, 85:15, 80:20, 75:25 and 70:30) and the formulated breads were assessed for their physicochemical and microbial characteristics. The bread with 30% stabilized rice bran supplementation showed highest crude protein (13.48%), crude fat (6.69%) and crude fiber (3.60%) contents, whereas control treatment (100% wheat flour) had lowest crude protein (11.64%), crude fat (2.43%) and crude fiber (1.56%) content. Loaf weight, redness (a*) and yellowness (b*) of the formulated breads increased with increase in stabilized rice bran; while loaf volume, specific volume, crust to crumb ratio and L* value decreased with the addition of stabilized rice bran. The supplementation of stabilized rice bran increased total bacterial and yeast and mould counts of bread from 2.84 × 10⁴ to 3.19 × 10⁴ and 1.49 × 10⁴ to 1.84 × 10⁴ cfu g^-1, respectively. During storage period of 4 days, microbial count and yeast and mould count of breads increased from 0.34 × 10⁴ to 6.41 × 10⁴ and 0.25 × 10⁴ to 3.32 × 10⁴ cfu g^-1, respectively. It may be concluded that supplementation of rice bran up 20% enhanced nutritional and overall acceptability scores.