Effect of Fermentation and Particle Size of Wheat Bran on the Antinutritional Factors and Bread Quality

Three local sudanese wheat cultivars, Debeira, El-Nielain and Sasaraib were obtained from Agricultural Research Corporation (harvest season 2002/03). Wheat bran was obtained from a local flour mill in Khartoum North. It was carefully sieved and classified as coarse, medium and fine bran size then fermented. Proximate composition, mineral content and anti-nutritional factors (tannin, phytic acid) were determined for all types of wheat bran. Results indicated that fermentation of wheat bran increased the percentage of crude fiber from 15.67 to 18.67%, 15.67 to 18.00%, 15.00 to 17.67%, protein content from 20.35 to 21.65%, 18.36 to 20.79%, 21.07 to 22.40% for coarse, medium and fine wheat brans, respectively. Carbohydrates percentage increased from 45.09 to 47.4% in fermented coarse wheat bran. Both anti-nutritional factors (tannins and phytic acid) were found to decrease significantly (P≤0.05) in coarse, medium and fine wheat bran. The tannin content decreased from 0.03 to 0.01, 0.07 to 0.05 and from 0.07 to 0.06 mg catechin/100 gm, respectively. Phytic acid decreased from 626.1 to 572.8, 740.4 to 367.1 and from 795.2 to 301.6 mg/100 gm, respectively. There is no change on the values of Ca and Fe contents of coarse wheat bran after fermentation. Also there was an increase in Ca content of fine and medium wheat bran. Fe content of medium wheat bran decreased from 0.03 to 0.02% but Fe content of fine wheat bran increased from 0.023 to 0.033%. There is a slight decrease in P content of coarse wheat bran after fermentation. The phosphorous content as percentage decreased in fermented medium and fine wheat bran from 0.004 and 0.003% to 0.002 and .002%, respectively. Bread specific volume values of the three cultivars with 10, 15 and 20% fermented wheat bran decreased with increase in the amount of wheat bran. Bread with 10% fermented coarse wheat bran gave the best results for all characteristics tested in organolyptic evaluation.