Improved process for inhibiting the formation of undesirable colour in animal or vegetable oils or fats and the oils or fats produced thereby

摘要

Discolouring of animal or vegetable oils or fats on exposure to air and light is prevented by incorporating not more than 0,05 per cent of colloidal copper, cobalt, cadmium or silver, or of carbonate of cobalt, copper, lithium, manganese, cadmium, barium, bismuth, nitrate of calcium, beryllium, lithium, acetate of sodium, copper, manganese, hydrate of cobalt, beryllium, copper, thorium, or of a mixture of cobaltous carbonate and copper carbonate with or without bismuth subcarbonate. Usually 0,00025--0,00050 per cent is used, determined to give the same weight of metal as is contained in the proportion of copper carbonate not colouring the oil or fat green but sufficient to enable the oil to transmit white light substantially without selection of the different frequencies. Lard cottonseed, china wood and linseed oils are specified for treatment. The Specification as open to inspection under Sect. 91 describes the treatment of natural oils or fats with up to 0,05 per cent of a metal or metallic salt. This subject-matter does not appear in the Specification as accepted.