Akademik Veri Yönetim Sistemi
Journal of Food, Agriculture and Environment, cilt.7, sa.3-4, ss.166-172, 2009 (SCI-Expanded)
Laboratory tests evaluated the wheat kernel hardness on the population density of two stored-insect pests and their deleterious effects on the technological properties of the bread wheat. Soft (SW) and hard (HW) bread wheat samples were infested with Rhyzopertha dominica (F.) and Tribolium confusum du Val, as internal and external grain feeders, respectively, at a rate of 2 adults kg-1 and stored for 5 months at 32°C and 60% relative humidity. Slightly higher populations of both insects were found in the SW than in the HW, being significant only for those infested with R. dominica. T. confusum only fed on the kernel germ (1.49-1.80%) but did not damage its endosperm and produced little amounts of debris (0.17-0.22%). In contrast, R. dominica fed on both kernel endosperm (46.12-74.25%) and germ (0.51-0.61%) and produced high amounts of debris (11.42-14.65%) from the HW and SW. With respect to the infestation, decrease in the test weight, kernel weight and flour yield, and increases in the moisture and ash contents were more severe in the SW than in the HW, and in those infested with R. dominica compared to those infested with T. confusum. Increase in the protein contents of both infested wheat by R. dominica was same. R. dominica caused great reduction in the flour quality compared to T. confusum: the protein and ash contents increased, and gluten content and sedimentation value decreased. Similarly, farinograph and extensigraph properties of the flour samples were more adversely affected by R. dominica than by T. confusum. Breads made from the SW and HW infested by both insects, exhibited reduced loaf volumes after 2 months of infestation period. The insect species significantly affected odor and taste but not internal characterictics. The intensity of an unpleasant taste and objectionable odor in the breads were detected after 4 months of infestation period.