Effects of blackpoint on grain composition and baking quality of New Zealand wheat

Abstract

Samples of Takahe and Kopara wheat affected by black point were separated into classes of different severity. Kernel weight, nitrogen content, alpha-amylase, and proteolytic activity of each class were determined. Kernel weight and nitrogen content increased with higher degree of infection. Alpha-amylase activity was higher, but proteolytic activity was lower in kernels from the highest severity class compared to sound kernels of the 2 cultivars. Scanning electron micrographs showed mycelial growth throughout the embryo and within the pericarp layer along the crease region of infected kernels. Fungi did not invade the endosperm. Samples of grain of each severity class were milled into flour for breadbaking. Bread volume decreased, the grain became more open, and the texture was less silky as the extent of blackpoint infection increased. No mycotoxins were detected. © 1986 Taylor & Francis Group, LLC.