Development of methods for neutralizing the free fatty acids of fatty coriander oil

In the present paper, the information on the process of enzymatic conversion of free fatty acids in fatty coriander oil (FCO) was considered. Enzymatic esterification was performed according to the following algorithm: FCO was treated with enzymes, purified by adsorbents with a variation of the basic process parameters, alcohols of a different nature were added. The quality of the samples of the purified FCO was determined by the basic physicochemical index - acid number. Ethanol (96 %) and glycerin (99.3 %) were used as reagents. Enzyme preparations (manufactured by «Novozymes» Denmark): Novozym 435, Lipozym TL IM were used as catalysts. Using the FCO fining methods, given in the paper, it was managed to reduce the acid number of oil from 17.0 mg KOH/g to 0.3 mg KOH/g. It was proved that using vacuum is an appropriate technological stage of enzymatic esterification of the FCO. Using molecular sieves for the FCO fining to reduce the content of water formed in the esterification and, thus, improve the conditions for the conversion reaction of free fatty acids - reduced acid number to less than 2.1 mg KOH/g was investigated. It was found that when adding molecular sieves in the FCO - reagent - enzyme system, water removal is not observed and their use does not decrease the acid number of oil at all. The fatty acid composition of the sample of the initial FCO was investigated by means of gas-liquid chromatography. It was found that in the initial FCO the percentage of the main fatty acids are the following: palmitic - 2.4 %, petroselinum - 71.3 %, oleic - 7.8 %, linoleic - 15.6 %. The authors have examined the process of adsorption of free fatty acids from the esterified FCO using the anionite EDE - 10P. It was found that the increase in the ratio of FCO to the adsorbent does not result in complete removal of free fatty acids and, accordingly, sufficient decrease in the acid number of the purified oil.