Indigenous food fermentations are one of the oldest forms of biotechnology, although the potential of the associated microorganisms has probably not yet been fully realised. Many food fermentative microorganisms are highly domesticated, although few studies have attempted to assess the extent of the genetic resource which is available, or which strains should be preserved for the future. Many bacterial and fungal fermented foods are based on the utilization of solid substrates. Fundamental studies on these model sytems could provide the necessary information to enable a more efficient exploitation of solid substrates in modern biotechnology. Oppurtunities exist for the use of traditional fermentative microorganisms in biotechnology, either directly or following genetic manipulation using conventional or molecular techniques. Examples are presented to show the use of food fermentative and related microorganisms for the production of food colours, flavours, enzymes, antimicrobials and health products. Chitosan, a polymer present in the hyphae of food fermentative fungi has applications in the food, pharmaceutical and agricultural industries.