What Is Free Fatty Acid Value

The acid number is defined as the mg koh required to neutralize the free fatty acids present in 1 g of sample.

What is free fatty acid value. Acid value is normally calculated in order to determine the amount of free fatty acids. Ffa is usually used to describe the ffa content of oils while acid number an is commonly used to describe the ffa content of finished biodiesel. With a little math we can use the same titration procedure we use to titrate wvo to determine ffa and an. It is a relative measure of rancidity as free fatty acids are normally formed during decomposition of triglycerides.

The free fatty acid in an oil is estimated by titrating it against koh in the presence of phenolphthalein indicator. However the free fatty acid content is expressed as oleic acid equivalents. The ffa value is a measure of the free fatty acids that can be released due to a break in the ester linkage connecting the fatty acids to the glycerol backbone of the triacylglycerol oil molecule. Free fatty acids ffa are the result of the breakdown of oil or biodiesel.

The mean values for free fatty acids ffa of oil before and after frying of samosa and chicken revealed that ffa was found to be significantly lower in oil before frying 0 26 0 11 and 0 30 0 05 than after frying 2 9 0 11 and 3 07 0 64 in the oil used for frying of samosa and chicken. Acid value is the mass of potassium hydroxide koh in milligrams that is required to neutralize one gram of chemical substance. Free fatty acids of the sample at ph 7 0 react with a chromogenous compound and decrease its color. To verify the quality of fats and oils acid value or free fatty acid can be used.