Nutritive Properties of Steam-Rendered Lard and Hydrogenated Cottonseed Oil

Abstract

The relative growth-promoting properties and digestibility of steam-rendered lard and hydrogenated cottonseed oil were determined by experiments with young male albino rats. Each fat was incorporated in an otherwise adequate diet in the proportions of 5, 15, 30, and 54%. The two fats had approximately the same growth-promoting value when the diets contained 5% of fat, but lard was superior when the diets contained the larger proportions of fat. The average growth-promoting value of all diets containing lard was superior to the average value of all diets containing hydrogenated cottonseed oil. Both lard and hydrogenated cottonseed oil induced maximum growth when the diets contained 30%, and minimum growth when the diets contained 5% of fat. Each fat was utilized least efficiently for growth when the diet contained 5% of fat, but each was utilized with approximately equal efficiency whether the diet contained 15, 30, or 54% of fat. Lard was superior in digestibility to hydrogenated cottonseed oil at each level of fat intake. The digestive coefficients for lard ranged from 95.9 to 97.4% with an average of 96.4% whereas those for hydrogenated cottonseed oil ranged from 91.0 to 95% with an average of 92.9%.