UABDivulga - Barcelona recerca i innovació

Flavours are compounds that provide smell and flavor. For this property, these molecules are very attractive as additives for food and cosmetic industries.

Flavours can be extracted from plants and fruits by physicochemical processes. Nevertheless, these direct extraction processes entail high costs because after the physic treatments that have to be applied to the solid feedstock (pressing, filtration, etc),  a set of steps are required for the subsequent purification of the desired compound. Despite this disadvantage, flavours obtained by direct extraction can be commercialized as natural products.

Chemical synthesis is considered as an alternative pathway to the direct obtaining of flavours, reducing this method the cost of the process. However, this methodology of synthesis has the disadvantage that obtained flavours can not be labelled as “natural”, reducing this fact the final prize of the product.

The enzymatic synthesis comes up as a biotechnological solution since flavors synthesized by this methodology can be labeled as “natural” but without taking on costs as high as those of the direct extraction.

Most of flavors are esters, and they can be synthesized from the corresponding acid and alcohol by the catalytic action of lipases.

The Bioprocess Engineering and Applied Biocatalysis group of de Chemical Engineering Department from UAB have carried out successfully a flavor enzymatic synthesis. The reaction is based in the ester formation, the ethyl butyrate, which has pine-apple smell, from ethanol an butyric acid. The biocatalysis allows the transformation of the food odor of the acid into the pine apple smell of the ester. The applied enzyme was a recombinant Rhizopus oryzae lipase produced by the research group in Pichia pastoris.

In the study, the optimal conditions of the flavor synthesis were determined by studying the effect of different parameters on productivity, such as temperature, speed shaking or enzyme concentration.