Effect of tempering conditions on white sorghum milling, flour, and bread properties

Authors: YOGANANDAN, MOHANA - Kansas State University; Bean, Scott; MILLER-REGAN, REBECCA - Kansas State University; DOGAN, HULYA - Kansas State University; PULIVARTHI, MANOJ - Kansas State University; SILIVERU, KALIRAMESH - Kansas State University

Submitted to: Foods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/18/2021
Publication Date: 8/21/2021
Citation: Yoganandan, M., Bean, S.R., Miller-Regan, R., Dogan, H., Pulivarthi, M.K., Siliveru, K. 2021. Effect of tempering conditions on white sorghum milling, flour, and bread properties. Foods. https://doi.org/10.3390/foods10081947.
DOI: https://doi.org/10.3390/foods10081947

Interpretive Summary: Compared to grains such as wheat and corn, methods for milling sorghum grain are not well established. To improve the production of sorghum flour, this research tested the effect of using room temperature or hot water to temper sorghum grain before milling. Tempering sorghum grain with room temperature water before roller milling was found to lead to improved milling properties of the grain with no negative effect on the final sorghum flour. Sorghum flour produced from grain that was tempered for 24 hours at room temperature was found to produce higher quality bread as well. This means room temperature tempering could improve sorghum flour production and flour end-use quality for baked foods.

Technical Abstract: The effects of room temperature water, hot water, and steam tempering methods were investigated on sorghum kernel physical properties, milling, flour, and bread making properties. Overall tempering condition and tempering moisture content was found to have significant effect on the physical properties. Milling properties were evaluated using a laboratory-scale roller milling flowsheet consisting of four break rolls and eight reduction rolls. Room temperature tempering (18% moisture for 24 h) led to better separation of bran and endosperm without negatively impacting flour quality characteristics i.e. particle size distribution, flour yield, protein, ash, damaged starch, and moisture content. Bread produced from the flour obtained from milling sorghum kernels tempered with room temperature water (18% m.c for 24 h) and hot water (16% m.c at 60 °C for 18 h) displayed better bread making properties i.e. high firmness, resilience, volume index, higher number of cells, and thinner cell walls when compared to other tempering conditions. Room temperature water tempering treatment (18% m.c for 24 h) could be a better pretreatment process for milling white sorghum kernels without negatively impacting the flour and bread making quality characteristics.