Abstract
For establishment of the standard method of carbonyl value analysis of fats and oils, collaborative studies were made on the method of Henick et al., stressing onto the agreement and reproducibility among data.
Good result was obtained by fixing the time for 5 minutes, which is defined as the elapsing time from addition of 4%-KOH-ethanol solution up to the time of dilution with ethanol.
The effect of peroxides on carbonyl value determination was also investigated for the stannous chloride reducing method of Mizuno et al.. The results indicated that carbonyl value was measured excessively when peroxides are present. Therefore, carbonyl value should be measured after removing the effect of peroxides.
Calculation of carbonyl value :
CO.V.=A/B
A; absorbance at 440mμ
B; sample weight in 5ml of sample-benzene solution (g)
