Physicochemical Properties and Consumer Acceptance of Wheat‐Germinated Brown Rice Bread during Storage Time

Abstract

Selected physicochemical properties and consumer acceptance of bread prepared from composite flour (wheat:germinated brown rice:germinated glutinous brown rice flours at 60:30:10 ratio) were evaluated during storage for 0, 3, and 5 d, and compared with wheat bread (0 d, control). During storage, color profiles and water activity (from 0.947 to 0.932) of crumbs of composite flour breads slightly changed, but moisture content drastically decreased along with increasing crumb hardness (from 4.16 N to 10.37 N). Higher retrogradation in bread crumb was observed particularly for 5-d stored bread (DeltaH = 2.24 J/g) compared to that of the fresh composite bread and the control (DeltaH = 0.70 and 0.51 J/g, respectively). Mean (n = 116) overall liking score of the fresh composite flour bread (0 d) was slightly lower than that of the control (7.1 compared with 7.6 based on a 9-point hedonic scale). At least 76% of consumers would purchase the fresh composite flour bread if commercially available. Breads were differentiated by textural (moistness, smoothness, and softness) acceptability with canonical correlation of 0.84 to 0.87. The signal-to-noise ratio values of the 5-d stored breads were lower than the control, due mainly to the non-JAR (not-enough) intensity responses for moistness, smoothness, and softness; the mean drop of liking scores for these attributes ranged from 2.42 to 2.98. Flavor acceptability and overall liking were factors influencing consumers' purchase intent of composite flour breads based on logistic regression analysis. This study demonstrated feasibility of incorporating up to 40% germinated brown rice flour in a wheat bread formulation. Practical Application: Our previous study revealed that flours from germinated brown rice have better nutritional properties, particularly gamma-aminobutyric acid (GABA), than the nongerminated one. This study demonstrated feasibility of incorporating up to 40% germinated brown rice flour in a wheat bread formulation. In the current U.S. market, this type of bread may be sold as frozen bread that would have a longer shelf life, or may be supplied as a food-service product that would be made-to-order or made fresh daily as currently practiced in some major grocery stores.

Influence of germination time of brown rice in relation to flour and gluten free bread quality

“…The formation of low molecular proteins and carbohydrates by germination yielded lower batter consistency and paste viscosity besides a decrease in WBC, overall they might improve texture as previously reported (Charoenthaikij et al 2010b;Watanabe et al 2004).…”

“…At bread level, Han et al (2012) found that rice lines with low water absorption produce fresh bread with a suitable volume and firmness. Presumably, that effect could explain texture improvement observed when partial replacement of wheat flour with germinated rice and pregerminated rice (Charoenthaikij et al 2010b;Watanabe et al 2004). It is interesting to notice that WHC of the soaked sample was significantly lower than that of samples germinated for 12 h and 24 h. Again, this result could be explained due to α amylase action that takes some time to degrade intact starch granules, changing its structure.…”

“…Despite their nutritional benefits, germinated brown rice flour, pregerminated brown rice flour and germinated glutinous brown rice flour have been only used for partial substitution (10-30 %) of wheat flour in breadmaking (Charoenthaikij et al 2010a(Charoenthaikij et al , b, 2012Watanabe et al 2004). This practice produces changes in the rheological properties of the batter, modifying dough handling, besides an improvement of crumb texture, increase of gas production during fermentation and retard bread staling (Charoenthaikij et al 2010b;Watanabe et al 2004). The late benefit likely related to the alfa-amylase action forming low molecular weight dextrin that could inhibit amylopectin retrogradation (Gray and Bemiller 2003).…”

Supplementation of common white bread by coriander leaf powder

“…Staling is a complex process involving several physical and chemical phenomena. Some of the significant changes occurring during staling are increased crumb firmness (9,10), softer crust, loss of flavor, and lower moisture content (11). Crumb firmness is the most widely used indicator of bread staling (12).…”

Application of Honey Powder in Bread and its Effect on Bread Characteristics

“…However, on each day the springiness of HP and control did not significantly differ from each other and they were lower than those of SHP and HNY which were again not significantly different from each other. Firmness, springiness and cohesiveness are the indicators of bread freshness [32]. Charoenthaikij reported a similar trend of increasing firmness with a decrease in both cohesiveness and springiness values over storage time in wheat flour bread substituted with germinated rice flour.…”