Chemical studies on the herring (<i>Clupea harengus</i>). II.—The free amino‐acids of herring flesh and their behaviour during post‐mortem spoilage

Abstract

Abstract The seasonal variation of the free amino‐acids in herring is determined; histidine and taurine are quantitatively the most important. No correlation was found between sexual maturity and content of total or individual amino‐acids. In post‐mortem spoilage, the taurine content remained constant, but the histidine content after a slight initial increase dropped to zero. Histamine developed 40‐50 h. after death. Three other imidazole‐like compounds were also detected. Leucine, valine, alanine, glycine, threonine and glutamic acid increased, but lysine and serine decreased. Aspartic acid and tyrosine, and arginine and (?)methionine were apparent after 40 and 58 h. respectively.