Effect of frost on the quality of samples of Janz wheat

The effect of frost damage on wheat grain quality was examined in samples o f an Australian Prime Hard wheat cultivar Janz. Wheat grain samples that we re lightly frosted, severely frosted and unfrosted were obtained from the R iverina district of New South Wales. Each frosted sample was separated by s ieving into 2 fractions by size using a commercial grader that was equipped with an aspirator. As the degree of frost damage in the samples increased, grain size decreased, flour extraction decreased, flour ash increased, flo ur colour deteriorated, dough strength decreased, baking quality decreased, alpha -amylase activity increased and falling number decreased. Quality as sessment of the separated grain fractions showed that the large grains (> 2 mm) in both lightly frosted and severely frosted crops were equal or bette r than the unfrosted sample in all tested quality parameters. The large gra in fraction fully met the Australian Prime Hard receival standards and was of quality commensurate with the grade. Separation of grain by size was cal culated to be commercially viable for up to 50% frost damage. A commercial flourmill purchased frosted feed grain, followed the sieving procedure, and produced large grain consistent with unfrosted wheat that was subsequently used for normal processing.