d-Amino Acids in Fermentative Foods

In recent years, d-amino acids have been shown to be present, in a free or bound state, in a wide variety of foods and beverages, and to exhibit properties that differ from those of l-isomers. It is anticipated that as more is learned about the properties of d-amino acids in foods, they will be applied for the improvement of food characteristics. In this section, we will summarize what is known about the distribution and metabolism of d-amino acids in foods and beverages, especially fermented types, as well as what is known about the enzymes involved in the metabolism of d-amino acids. In addition, applications in which d-amino acids are being used to improve the characteristics of food are described.