Germination conditions affect selected quality of composite wheat-germinated brown rice flour and bread formulations.
Brown rice has been reported to be more nutritious after germination. Germinated brown rice flours (GBRFs) from different steeping conditions (in distilled water [DI, pH 6.8] or in a buffer solution [pH 3] for either 24 or 48 h at 35 degrees C) were evaluated in this study. GBRF obtained from brown rice steeped at pH 3 for 48 h contained the highest amount of free gamma aminobutyric acid (GABA; 67 mg/100 g flour). The composite flour (wheat-GBRF) at a ratio of 70 : 30 exhibited significantly lower peak viscosity (PV) (56.99 - 132.45 RVU) with higher alpha-amylase activity (SN = 696 - 1826) compared with those of wheat flour (control) (PV = 136.46 RVU and SN = 1976). Bread formulations, containing 30% GBRF, had lower loaf volume and greater hardness (P < 0.05) than the wheat bread. However, the hardness of bread containing 30% GBRF (except at pH 6.8 and 24 h) was significantly lower than that of bread containing 30% nongerminated brown rice flour (BRF). Acceptability scores for aroma, taste, and flavor of breads prepared with or without GBRFs (30% substitution) were not significantly different, with the mean score ranging from 6.1 (like slightly) to 7 (like moderately). Among the bread formulations containing GBRF, the one with GBRF prepared after 24 h steeping at pH 3 had a slightly higher (though not significant) overall liking score (6.8). This study demonstrated that it is feasible to substitute wheat flour with up to 30% GBRF in bread formulation without negatively affecting sensory acceptance. 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 30% germinated brown rice flour in a wheat bread formulation without negatively affecting sensory acceptance. In the current United States market, this type of bread may be sold as frozen bread which would have a longer shelf life. Further study is thus needed.
Charoenthaikij
Phantipha
P
Dept. of Product Development, Faculty of Agro-Industry, Kasetsart Univ., Chatuchak, Bangkok, Thailand.
Jangchud
Kamolwan
K
Jangchud
Anuvat
A
Prinyawiwatkul
Witoon
W
Tungtrakul
Patcharee
P
D000293:Adolescent; D000328:Adult; D001939:Bread / Q000032:analysis*; D055598:Chemical Phenomena; D003258:Consumer Behavior; D005433:Flour / Q000032:analysis*; D005511:Food Handling / Q000379:methods*; D018525:Germination; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D055595:Mechanical Phenomena; D008875:Middle Aged; D012275:Oryza / Q000737:chemistry*; D025341:Principal Component Analysis; D011786:Quality Control; D036226:Seedlings / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry; D012677:Sensation; D013785:Thailand; D013997:Time Factors; D014908:Triticum / Q000737:chemistry; D055815:Young Adult