Lysinoalanine: presence in foods and food ingredients.

Lysinoalanine, N6-(DL-2-amino-2-carboxyethyl)-L-lysine, an unusual amino acid implicated as a renal toxic factor in rats, has been found in proteins of home-cooked and commercial foods and ingredients. Although it has been reported to occur in both edible and nonfood proteins only after alkali treatment, it has now been identified in food proteins that had not been subjected to alkali. Lysinoalanine is generated in a variety of proteins when heated under nonalkaline conditions.