Abstract: Novel odor-flavor materials and methods for producing the same are disclosed comprising a mixture of various gamma-lactones. In the preferred embodiment, a member of the genus Pityrosporum is cultured on a culture medium and is stimulated to produce a gamma-lactone containing flavor-fragrance mixture through its incubation with a lipid rich precursor. The preferred species for use in producing these gamma-lactone containing materials are P. canis, P. pachydermatis, P. orbiculare and P. ovale. The preferred lipid-rich materials include triolein, sebum, lecithin, oleic acid, and SAB with human sebum, and Tween-80. The resulting gamma-lactone rich products comprise the following lactones: gamma-hexa, gamma-hepta, gamma-octa, gamma-nona, gamma-deca, gamma-undeca, and in the case of P. canis, gamma-dodecalactone. The resultant flavor-fragrance product is all natural, exhibiting extremely pleasing taste and/or flavor characteristics.

Abstract: A novel method of detecting and diagnosing Pseudomonas aeruginosa infections by monitoring sample headspace concentrations of selected methyl ketones, particularly 2-nonanone and 2-undecanone. In an alternate embodiment, such diagnosis may be made by monitoring the headspace concentration of methyl mercaptan to diagnose the extent of a Pseudomonas aeruginosa infection. Expeditious methods for increasing such concentrations are also disclosed which include additions of selected nutrients to incubated sample mixtures.