Impact of Wheat Fiber on Frozen Dough Shelf Life and Bread Quality

Abstract

27Freezing and prolonged frozen storage of dough results in constant deterioration in the overall 28 quality of the final product. In this study the effect of wheat bran and wheat aleurone as sources 29 of arabinoxylan (AX) on the quality of bread baked from yeasted frozen dough was investigated. 30Wheat fiber sources were milled to pass through a 0.5 mm screen, pre-hydrated for 15 minutes 31 and incorporated into refined wheat flour at 15% replacement level. Dough products were 32 prepared from refined flour (control A), whole wheat flour (control B), aleurone-composite flour 33 (composite flour A), bran-composite flour, (composite flour B) and stored at -18 ˚C for 28 34 weeks. Dough samples were evaluated for bread making quality at zero time, 14 weeks and 28 35 weeks of storage. Quality parameters evaluated were loaf weight, loaf specific volume and 36 crumb firmness. Composite flour bread samples showed the most resistance to freeze damage 37 (less reduction in the overall product quality) indicating a possible role of some fiber components 38 (e.g. AX) in minimizing water redistribution in the dough system and therefore lessening adverse 39 modifications to the gluten structure. The data suggest that the shelf life of frozen dough and 40 quality of obtained bread can be improved with the addition of an AX source.41

Properties of Arabinoxylans in Frozen Dough Enriched with Wheat Fiber

“…The composition of the wheat flours, bran, and aleurone has been previously discussed (Adams et al 2015(Adams et al , 2017. The composition of the wheat flours, bran, and aleurone has been previously discussed (Adams et al 2015(Adams et al , 2017.…”

“…Frozen storage and thawing conditions were as described by Adams et al (2015). Yeasted bread dough was prepared on a 100 g scale from controls (refined and 100% whole wheat flour) and composite flours (refined flour substituted with either aleurone or bran, both at 15% replacement levels) according to AACC International Approved Method 10-10.03.…”

“…Wheat aleurone (24% arabinoxylan) was obtained from Horizon Milling (Wichita, KS, U.S.A.). Protein, starch, dietary fiber, and ash contents of refined flour and fiber materials have been previously reported (Adams et al 2015). Enzymes used were Termamyl 120 L a-amylase, Neutrase 0.8 L bacterial protease (Novozymes, Bagsvaerd, Denmark), and amyloglucosidase from Aspergillus niger (Megazyme International, Bray, Ireland).…”

“…Yeasted bread dough was prepared on a 100 g scale from controls (refined and 100% whole wheat flour) and composite flours (refined flour substituted with either aleurone or bran, both at 15% replacement levels) according to AACC International Approved Method 10-10.03. Frozen storage and thawing conditions were as described by Adams et al (2015). Prior to analysis, fresh dough (before fermentation) and frozen dough (right after removing from the freezer) were freeze-dried with a Virtis 25EL freeze dryer (Virtis, Gardiner, NY, U.S.A.).…”

“…These fiber sources resulted in decreased water mobility in the dough system, which increased resistance to freezing and freeze damage (i.e., decreased the overall product quality) (Leray et al 2010;Lu and Seetharaman 2013;Hamed et al 2014). Our previous work also suggested that addition of these wheat fibers rich in arabinoxylan could reduce the negative impact of frozen storage on dough rheological properties and thus improve bread quality characteristics such as high loaf volume and uniform crumb structure (Adams et al 2015(Adams et al , 2017. Arabinoxylan with water-extractable and water-unextractable portions may therefore help reduce the problem of loss of quality in frozen doughs upon freezing and prolonged frozen storage.…”