Effects of particle size on the properties of whole-grain soft wheat flour and its cracker baking performance

• WWF particle size didn't affect water-, sodium carbonate-, and lactic acid-SRC values.
• Reduction of WWF particle size increased cracker dough resistance to extension, and extensibility.
• Reduction of WWF particle size improved cracker baking performance.
• Lactic acid-SRC and GPI of refined flour can predict cracker performance of its WWF.

In order to evaluate the effects of particle size on the properties of whole-wheat flour (WWF) and its cracker baking performance, two commercial U.S. soft wheat cultivars from different wheat classes (Eltan from Soft White Winter and Gro-Mor from Soft Red Winter) were used. Based on median diameter, WWFs of four different particle size distributions for each wheat cultivar were reconstituted after further grinding bran and shorts fractions of its corresponding flour. The median diameters of each WWF were 171.6 ± 0.3, 121.8 ± 3.4, 103.8 ± 2.1 and 89.9 ± 0.6 μm for soft white winter, and 170.0 ± 0.6, 120.8 ± 3.4, 106.3 ± 0.1 and 95.6 ± 1.8 μm for soft red winter, respectively. For both wheat cultivars, with decreasing particle size, the damaged starch contents of WWFs were increased significantly, but no significant changes in water, sodium carbonate and lactic acid-solvent retention capacity values were observed. Reduction of WWF particle size significantly affected dough rheological property, which showed an increase in the maximum resistance to extension and extensibility of cracker dough after being laminated and sheeted. Cracker baking results exhibited a significant increase in the ratio of stack height to dough weight and a decrease in bran specks on surface as WWF particle size reduced.