Utilization of an auxotrophic strain of the yeast Yarrowia lipolytica to improve γ‐decalactone production yields

γ‐Decalactone is an aroma compound with a pleasant peachy odour. Most industrial processes use the bioconversion of ricinoleic acid by yeasts to produce γ‐decalactone. Peroxisomal β‐oxidation activity is responsible for the bioconversion. Some yeasts, Yarrowia lipolytica in particular, grow during the bioconversion, yielding a low bioconversion rate. Auxotrophy for uracil of a genetically engineered Y. lipolytica strain was used to prevent growth in the bioconversion medium. β‐Oxidation activities and γ‐decalactone production of the auxotrophic strain were measured and compared with a wild‐type strain in media supplemented or not. Induction of β‐oxidation was observed in the non‐supplemented medium, although to a lesser extent than in supplemented medium. Aroma productivity of the auxotrophic strain in the supplemented medium was similar to that observed for the wild‐type strain in both media. However, in the non‐supplemented medium the productivity of the auxotrophic strain was 10–20‐fold higher.