Effect of the Mill Type on Sorghum Storage Stability ( Sorghum bicolor (l.) Moench) Flour

Abstract

Whole grains undergo relatively few changes during storage. However, enzymes, fatty acids, and other components kept in separate compartments begin to interact during milling, causing physicochemical and functional changes in flours. Furthermore, although the flour has a low water content, it may be susceptible to deterioration due to the presence of microorganisms. The aim of this study was to evaluate the physicochemical and microbiological changes occurring in white and brown sorghum flours obtained through different milling methods during a 150 day storage trial. During the evaluation, molds and yeasts were found within the limits set by the Argentinian Food Code in all samples at the beginning of the trial. Total coliforms and mesophilic aerobes decreased, while total acidity increased with storage time. Almost all of the samples showed no detectable peroxide values at the beginning or end of the trial. A decrease in induction times was observed from 90 days onward, after which the values remained stable. Viscosity profiles increased with the storage time. Flours showed good stability up to 150 days of storage and were not affected by the milling type.