Effect of heat treatments on starch pasting, particle size, and color of whole-grain barley

Citation

Boyd, L., Storsley, J., Ames, N. (2017). Effect of heat treatments on starch pasting, particle size, and color of whole-grain barley, 94(2), 325-332. http://dx.doi.org/10.1094/CCHEM-04-16-0100-R

Plain language summary

Heat processing treatments are beneficial to reducing microbial contaminants in whole grains prior to human consumption. However, the effects of these heat treatments on properties of barley that may impact its milling and food processing quality are not well understood. The aim of this study was to examine the effects of three different heat treatments (micronization, roasting, and conditioning) on whole-grain barley physical and functional properties including color, flour particle size after milling and flour pasting viscosity. These effects were examined using three diverse barley cultivars (CDC Rattan, CDC McGwire, and CDC Fibar) to determine if varieties respond differently to heat processing. All three heat treatments increased flour slurry viscosity (a measure of flour processing quality), but this effect was observed in only two out of the three barley cultivars. Roasting and conditioning resulted in reduced flour particle size upon milling, which could influence further end product processing and nutritional properties. Heat treatments also altered kernel color. Overall, this research shows that heat treatments can change properties of barley that may affect its function in food applications.

Abstract

© 2017 AACC International, Inc. Barley β-glucan has cholesterol-lowering properties and can be positively affected by heat treatments. The aim of this study was to examine the effects of heat treatments of whole-grain barley on starch pasting, particle size, and color. Three heat treatments (micronization, roasting, and conditioning) were performed on three cultivars of barley (CDC Rattan, CDC McGwire, and CDC Fibar). All three heat treatments increased peak, breakdown, setback, and final viscosity of CDC Rattan and CDC Fibar. However, they had little effect on the starch-pasting profile of CDC McGwire. Roasting and conditioning reduced the mean particle size compared with untreated particles, whereas micronization had minimal effect. Heat treatments reduced L∗ and increased a∗ and b∗ compared with no treatment. Overall, this research shows that heat treatments can change other properties of barley that may affect its function in food applications.

Publication date

2017-03-01

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