| abstract |
The invention relates to a process for the preparation of aroma esters by esterifying a C2-6 aliphatic carboxylic acid or a mixture of such acids with a C2-6 aliphatic alcohol or with a mixture of such alcohols in an organic solvent at a temperature of 5-70 °C in the presence of a hydrolase enzyme which is stable in the solvent applied, under maintaining the acid:alcohol molar ratio between 1:0.5 and 1:10. According to the invention the starting acid content of the reaction mixture is adjusted to 75-99 % of the acid concentration which causes substrate inhibition, the acid and the alcohol consumed in the reaction are supplemented continuously, at the rate of their consumption, and the water content of the reaction mixture is maintained at 0.01-2.0 % by weight throughout the whole reaction. |