|Graybosch, Robert - Bob|
Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/17/2002
Publication Date: 7/31/2003
Citation: Gang, G., Jackson, D., Graybosch, R.A., Parkhurst, A.M. 2003. Wheat tortilla quality: impact of amylose content adjustments using waxy wheat flour. Cereal Chemistry. Interpretive Summary: Tortilla consumption is rapidly increasing in the United States. Tortilla sales for 2000 in the U.S. reached the $4.4 billion mark and are expected to hit $5.7 billion dollars in sales by the year 2002 (Anonymity 2001). Americans consumed 7 billion pounds of tortillas (not including tortilla chips) in 2000, which is equivalent to about 85 billion tortillas or nearly one tortilla per capita per day. Shelf-life is considered a primary aspect of tortilla quality. A study was undertaken to determine if newly developed waxy (amylose-free) wheats could be used to create tortilla flour blends useful in developing tortillas with extended shelf life. Based on our observation of an initial increase inextensibility with reduced-amylose tortillas, adding 10-20% waxy flour into wild type flours should be ideal for restaurant (on-site) tortilla production and/or circumstances where tortillas are consumed shortly (within a day) after production. The optimal flour amylose content for hot-press wheat tortilla products is 24-26%. Commercial production of waxy winter wheats for this and other food processing uses could lead to greater demand for the produce of American wheat farmers.
Technical Abstract: Amylose content is closely related to wheat flour pasting/thermal properties, and thus affects final food qualities. Fourteen flour blends with amylose content ranges between <1% and 29% were used to study tortilla production and quality parameters. Reduced amylose contents decreased dough stickiness and pliability;low amylose doughs were also very smooth in appearance. Very low flour amylose content was associated with earlier tortilla puffing and poor machinability during baking, darker color, low opacity, larger diameters, and reduced flexibility after storage. Tortilla texture analysis indicated that lowering amylose contents gave fresh tortillas higher extensibility; after three or more days storage, however, low amylose flours required more force to break the tortillas and the rupture distances became shorter. These results, as reflected in covariate analysis, were not impacted by the flour blend¿s protein content, swelling volume/power, SDS-sedimentation volume, Mixograph dough development time, or Mixograph tolerance score. Based on our observation of an initial increase in extensibility with reduced-amylose tortillas, adding 10-20% waxy flour into wild type flours should be ideal for restaurant (on-site) tortilla production and/or circumstances where tortillas are consumed shortly (within a day) after production. The optimal flour amylose content for hot-press wheat tortilla products is 24-26%.