Nutraceutical tortillas and tortilla chips prepared with bran from specialty sorghums

Abstract

The effects of sorghum bran addition on table tortillas and tortilla chip properties were evaluated. Texture, phenol content, antioxidant activity, and sensory characteristics were evaluated. Texture was measured by objective and subjective tests. Products were analyzed for phenols following the Folin-Ciocalteu procedure and for antioxidant potential following the ABTS (2,2'-azinobis (3- ethylbenzothiazoline-6-sulfonic acid) method. Sensory properties were evaluated using a nine point hedonic scale. Bran from two specialty sorghums: sumac (high tannin) and black (high anthocyanins) was added at 0, 5, and 10% to table tortillas and tortilla chips. For table tortillas the interaction of sorghum bran with an antistaling formula containing guar gum, carboxymethylcellulose and maltogenic alpha-amylase was assessed. Tortillas containing sorghum bran had a more friable structure than the control. This detrimental effect was overcome by the antistaling formula. Additives made fluffier tortillas with improved texture and appearance. Tortillas containing sorghum bran and the antistaling formula were acceptable to panelists. At 5% sorghum bran inclusion, there was no significant difference in sensory attributes from the control aside from appearance. Tortillas containing sorghum bran had a dark natural color comparable to that of blue corn tortillas. Tortilla chip texture was not significantly affected by addition of bran to the formula. As in table tortillas, addition of sorghum bran produced minor changes in the texture and flavor of the product, but a significant change in appearance acceptability. Tortilla chips had a dark color, comparable to the one of blue corn tortilla chips. Sumac bran yielded larger amounts of phenols and antioxidant activity than black bran. Levels of phenols and antioxidant potential increased with increased bran. Although processing caused a measurable loss of sorghum bran antioxidants, table tortilla and tortilla chips were still a significant source of phenols and antioxidant activity. The addition of sorghum bran produced tortillas and tortilla chips with increased levels of dietary fiber and antioxidants, without adversely affecting other sensory properties.