44E-27 |
Effects of amylose and beta-glucan on quality of wheat flour tortillas containing 20% barley flour |
S. PASCUT1, N. Ames2, N. Kelekci1, and R. D. Waniska1. (1) Cereal Quality Lab., Texas A&M Univ, Dept. Soil & Crop Sci, College Station, TX 77843-2474, (2) Cereal Res Ctr, Agr & Agri Food Canada, Winnipeg, MB MB R3T 2M9, Canada Barley replaced wheat flour in tortillas to improve their nutritional value and shelf stability. The barley flour fraction attained from remilling the bran was evaluated. The barley flour varied in amylose (0-43%) and beta-glucan (4-10%) contents. Pilot plant equipment and a commercial formula were used to prepare flour tortillas. Dough and tortilla properties were evaluated by using subjective and objective methods. More water (6%) in the formula was required when 20% barley flour replaced wheat flour. This yielded doughs with similar rheology as determined by the stress relaxation method. Tortillas containing 20% barley flour were similar to commercial wheat flour tortillas, but some had light brown appearance and lower "L" values. Tastes of tortillas ranged from similar to wheat tortillas to distinctive barley characteristics. For tortillas containing 20% normal amylose barley flours (23-27% amylose), the diameter decreased, opacity was unchanged and the force to rupture increased as beta-glucan level increased. Tortillas containing 20% high amylose barley flour (38-43% amylose) had decreased diameter, while tortillas containing no amylose barley flour exhibited less opacity. Less opaque tortillas were also obtained when 25% barley flour containing no amylose was incorporated. For tortillas containing 20% barley flour with higher levels of beta-glucan (7-10%), the diameter decreased and opacity and texture were unchanged as amylose content increased. Addition of barley flour substantially increased the soluble fiber in wheat flour tortillas. High levels of amylose and beta-glucan in barley flour adversely affected tortilla properties. Tortillas containing 20% barley flour (4-6% beta-glucan with normal amylose content) were similar to control wheat flour tortillas.
Session 44E, Nutraceuticals & Functional Foods
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