Changes in free and protein-bound amino acids in elderberry fruit (Sambucus nigra) during maturation.

Abstract

AbstractElderberry fruit was analysed for free and protein‐bound amino acids during ripening and senescence. Maturation was characterised by an appreciable decrease in the total amino acid content, free and bound, and an increase of the total free amino acid concentration. The latter was mainly due to the massive rise of leucine, tyrosine, and phenylalanine which occurred during the late stages in the ripening process. These three amino acids accounted for 68 % of the total free amino acid content in ripe fruit vs 9% in the green fruit. The transition from optimal ripeness to senescence was associated with a slight increase of the total protein‐bound and free amino acid contents. Assessment of the nutritional value of elderberry protein by comparison to whole egg revealed a chemical score of 0.94 for the total essential amino acids, indicating elderberry to be a good source of high biological value protein and thus a suitable source of raw material for a variety of food and dietary products.