Milling method affects the physical properties of black bean flour

Background and objectives Dry bean milling has attracted interest due to the increased need for nonwheat ingredients available for food applications. The objective of this study was to examine the physical and flow properties of black bean flour produced using a variety of laboratory mills and mill settings. Findings Flour from mills which utilized screens (cyclone mill, centrifugal mill, and hammer mill) showed significantly different characteristics than flour from mills without a screen (disk mill and stone mill). Geometric mean size of flour particles was negatively correlated with starch damage (r = -.92), L* (r = -.94), angle of repose (r = -.94), and angle of slide (r = -.80 to -.90, depending on surface material) and positively correlated with moisture content (r = .72) and loose bulk density (r = .72). Finely ground flour resulted in particles that tended to be less circular and more elongated and had high angles of repose and slide. Conclusions Milling method significantly affected (p < .05) physical and flow properties of black bean flour. Significance and novelty These findings can be used by food processors in selecting a milling method that favors the production of black bean flour with the desired physical properties.