Hexanal is an alkyl aldehyde found in human biofluids. Human milk samples collected from women contains hexanal. Among mediators of oxidative stress, highly reactive secondary aldehydic lipid peroxidation products can initiate the processes of spontaneous mutagenesis and carcinogenesis and can also act as a growth-regulating factors and signaling molecules. In specimens obtained from adult patients with brain astrocytomas, lower levels of n-hexanal are associated with poorer patient prognosis. Hexanal has also been identified as a uremic toxin according to the European Uremic Toxin Working Group (PMID:22626821 ). Hexanal is a volatile compound that has been associated with the development of undesirable flavours. The content of hexanal, which is a major breakdown product of linoleic acid (LA, n - 6 PUFA) oxidation, has been used to follow the course of lipid oxidation and off-flavour development in foods, and have been proposed as one potential marker of milk quality. A "cardboard-like" off-flavour is frequently associated with dehydrated milk products. This effect is highly correlated with the headspace concentration of hexanal. (Food Chemistry. Volume 107, Issue 1, 1 March 2008, Pages 558-569, PMID:17934948 , 17487452 ).
Belongs to the class of organic compounds known as medium-chain aldehydes. These are an aldehyde with a chain length containing between 6 and 12 carbon atoms.