Gamma-decalactone (GDL) is a cyclic ester with an intense peach-oil smell, detectable at a concentration below 5 mg/dm3. This compound is applied in the food industry to give appropriate organoleptic properties to products such as: beverages, bakery products, desserts, sweets or chewing gums. GDL comes under the GRAS status (Generally Recognized As Safe) and it is considered to be a safe food additive. Lactone can be produced using chemical or biotechnological methods. The increasing consumer awareness and the current trend towards bio-products contribute to the popularisation of biotechnological synthesis of the γ-decalactone. A difficulty in the production of GDL with the participation of microorganisms is its separation from the biotransformation medium, which is a mixture of metabolites of microorganisms and an unreacted lipid substrate (ricinoleic acid). The objective of the research study was an attempt to separate through adsorption the γ-decalactone (GDL) from biotransformation media, where a substrate was castor oil transformed into a fragrant compound by the Yarrowia lipolytica yeast. The adsorption efficiency was analysed with the use of two adsorbents: Amberite XAD-4 and vermiculite. Of the two adsorbents tested, more effective when adsorbing lactone from the media, during the logarithmic growth phase of yeast (the 4th day of biotransformation), was Amberlite XAD-4. Circa 61 ± 3 % of lactone could be absorbed 10 minutes after the adsorbent had been introduced into the reaction medium. The initial GDL adsorption rate on the Amberite XAD-4 was 4.365×10-3 g GDL/g adsorbent/min and it was about 2.8 times higher than that on the vermiculite. The extension of biotransformation time (up to 7 days) resulted in the decrease in the adsorption efficiency.
γ-decalactone, adsorption, Amberlite XAD-4, vermiculite, Yarrowia lipolytica