No abstract

Summary A method is described which permits application of the antimony trichloride spectrophotometric method to the determination of gossypol in a variety of cottonseed products. Gossypol is determined by means of the following series of operations: 1. extraction of gossypol from cottonseed or cottonseed products by use of chloroform or aqueous ethanol; 2. isolation of gossypol from the extracts by use of aqueous alkali; and 3. application of the antimony trichloride‐spectrophotometric test. Data are presented to show the results obtained by application of this procedure to the determination of gossypol in pigment glands, raw cottonseed meats, cooked cottonseed meats, hydraulic‐ and screw‐pressed meals, solvent‐extracted meals, gland‐free meals, and oils, both expressed and solvent‐extracted.

Summary Hardness is an important index in the performance of confectionery and other fats. Using an instrument and technique which were essentially a modification of those used in the Brinell test as applied to metals, the effect of composition and polymorphic form on the hardness of fats was investigated. It was found that the hardness of a given sample of fat was influenced by the degree of tempering to which the sample had been subjected. Hardness always increased as the components of a fat were converted to higher‐melting polymorphs. However the hardest test specimens were not obtained with the highest tempering temperatures. Presumably the use of too high a temperature in tempering melted some of the lowermelting polymorphs and allowed them to resolidify in larger crystals producing a softer matrix. Adding progressively larger amounts of one fat to another generally increased or decreased the hardness of the mixture in a more or less uniform manner. Adding small amounts of liquid oil to a hard fat greatly decreased the hardness index. Apparently the hardness index of a given fat decreases as the crystal size increases. It is believed that fats containing a sizable proportion of liquid component will become softer on prolonged storage because the presence of the liquid component makes possible a gradual increase in crystal size.