Catalyzes a Baeyer-Villiger oxidation reaction, i.e. the insertion of an oxygen atom into a carbon-carbon bond adjacent to a carbonyl, which converts ketones to esters or lactones using NADPH and/or NADH as an electron donor. Preferentially converts short-chain aliphatic ketones like 2-decanone, 3-decanone and 4-decanone. Some acyclic ketones are converted not only to the alkylacetates, but also methyl- and ethylesters are obtained, indicating insertion of oxygen on both sides of the keto group. Belongs to the FAD-binding monooxygenase family.