The 2-and 3-hydroxy fatty acids (2- and 3-OH-FAs) are characteristic minor fatty acids in biota. They were detected as members of different lipid classes isolated from animals, plants and microorganisms. However, very limited information was available on their presence in food.One aim of the present study was to provide basic knowledge on the occurrence, the variety, and the quantities of 2- and 3-OH-FAs in different food samples. Since 2- and 3-OH- FAs are chiral, it was of additional interest to investigate the enantiomer distribution of the compounds detected in foodstuffs. Given the low amounts that could be expected, highly selective and sensitive methods for quantitative and enantioselective determinations had to be developed.Little is known about the effects of 2- and 3-OH-FAs as part of lipid membranes. For this reason, additional experiments were carried out to investigate the influence of individual 2- and 3-OH-FAs on the organisation of lipid model membranes including the aspect of chirality.