Abstract
The authors attempted to find the relation between the foaming tendencies and the polymerization of fatty acid and nutritional value of kind of oil used for different stages of thermal oxidation.
Soybean oil, rape oil, seasame oil, coconut oil, olive oil, whale oil, lard, and tallow were heated at 180°C for 1 to 50hr., and the changes in their foam extensions and acid values were compared.
Also the contents of dimer and secondary product fraction in fatty acids obtained from those oils with different stages of thermal oxidation were measured by a Silica-gel column chromatography.
Rats were fed on those frying oils with varied 26mm, 40mm and 80mm of foam extensions, and also the effects of supplement of monomeric ester, dimeric ester and secondray products were examined.
