Cereal Chem 68:133-138   |  VIEW ARTICLE

Effects of Frost and Immaturity on the Quality of a Canadian Hard Red Spring Wheat.

K. R. Preston, R. H. Kilborn, B. C. Morgan, and J. C. Babb. Copyright 1991 by the American Association of Cereal Chemists, Inc. 

A Canadian hard red spring wheat, variety Neepawa, was subjected to controlled freezing in the field during maturation for two years. The overall quality of untreated (control) seed showed significant improvement during maturation until seed moisture reached approximately 45%, after which changes were much less evident. Kernel hardness, kernel weight, test weight, wheat ash, milling quality parameters (yield, flour ash, and color), and physical dough properties showed large changes (improvements) during maturation, whereas protein and remix baking quality parameters showed much smaller changes. The response of quality characteristics to frost was dependent on both temperature and maturity. At early maturity, temperatures below -3 C resulted in decreased kernel weight and protein content but increased kernel hardness. Effects were less evident at later maturity (seed moisture below approximately 45%). Low- temperature treatment had little effect on dough strength properties. However, treatment at all but the most mature stages resulted in large, significant increases in starch damage and farinograph absorption. Milling- related parameters (test weight, wheat ash, flour ash, flour color, and yield) were all adversely affected by low-temperature treatment except at the most mature stages. Remix baking quality (loaf volume, baking strength index, and crumb and crust characteristics) was also adversely affected during the early maturation phase.