RAPID ESTIMATION OF PEROXIDE CONTENT OF SOYBEAN OIL BY MEASURING THERMOLUMINESCENCE

Thermoluminescence measurements can serve as a simple and rapid procedure for the estimation of peroxide content of soybean oil. The thermoluminescence intensity, measured at 100 degrees C, increases in proportion (r = 0.978) to the peroxide value (from 0.5 to 18.0 meq/kg) of soybean oil, without any interference by the tocopherol contents. The emission spectrum had a maximum wavelength at around 440-480 nn, suggesting that excited triplet carbonyls formed during thermal decomposition of hydroperoxides are involved. The thermoluminescence measurement is readily available for the simple and rapid estimation of the peroxide content of soybean oil, with no need for chemical reagents and delicate skills.