Chapter 28 - Occurrence of D-Amino Acids in Food

Abstract

The importance of amino acids is widely recognized in various fields, particularly in the field of nutrition. Their usefulness has two aspects: the first is in the role of supplementary nutrients; the second is for their physiological or pharmacological functions. The amino acid score has been used to evaluate the nutritive value of food proteins. D-amino acids commonly occur in the diet, in particular in fermented foods, as well as in fresh fruits and vegetables. Although there is a lack of experimental evidence on the risks of D-amino acid intake, the production of foods with low amounts of D-amino acids is important to human health. The concentration and the kinds of D-amino acids occurring in foods seem to depend on both the manufacturing process and starter cultures. The carefully selected starter culture and controlled technology may result lower D-amino acid amine content in fermented foods. Detection of an unnatural enantiomer, or the ratio of enantiomers, can be used to determine the authenticity of a product, as a marker for the extent of processing, and may be useful for assessing food quality. Alternatively, the presence of a higher amount of D-amino acid may indicate bacterial contamination of the product.