The Effect of Heat on the Lysine and Methionine in Sunflower Seed Oil Meal

Abstract

The principal deficiency in commercial sunflower seed oil meal when used as a supplementary protein source in practical type diets for chicks and poults appears to he lysine (McGinnis, Hsu and Carver, '48; Slinger, Hill, Gartley and Branion, '49). The latter workers used an expeller-processed sun flower seed oil meal which analyzed 2.7% lysine on a 16% nitrogen basis. This value may be compared with 3.8% found by Block and Boiling ('45) in a solvent-processed meal. The evident discrepancy could be attributed to lysine destruction caused by exposure of the meal to high temperatures during the expeller processing, and is not unexpected in view of the conclusion of Clandinin and Robblee ('50) that the great variability in the nutritive value of commercial sunflower seed meals results from excessive processing temperatures. The experiments described, herein, were conducted to study the effects of controlled conditions of heating on the lysine and methionine in sunflower seed oil meal. There is no evi dence in the literature to suggest that methionine is deficient 1The data reported in this paper are taken in part from a thesis presented by J. C. Alexander in partial fulfillment of the requirements for the degree of Master of Science in Agriculture, University of Toronto, 1951. The investigation was supported in part by a grant from Toronto Elevators Ltd., Toronto, Ontario, and J. C. Alexander was holder of a fellowship from the Ontario Research Council. 2The authors are indebted to Co-op Vegetable Oils Ltd., Altona, Manitoba, for