SUGAR‐AMINO ACID INTERACTION IN THE DIFFUSATE OF WATER EXTRACT OF BEEF AND MODEL SYSTEMS

Abstract

SUMMARYDiffusates of water extract of beef and model systems containing amino acids or sugars, or both, in approximately the same concentrations as in beef diffusate were heated at 125°C for up to 60 min. Quantitative analyses of amino acids and sugars were performed. A brothy odor developed on boiling the diffusate (30 min of heating), but there were minor changes in amino acid concentrations except for arginine. After pyrolysis (45 min of heating), roast aroma and brown color developed and there was 40‐60% loss of most amino acids. Glucose and fructose concentrations were only slightly affected during boiling, but ribose decreased about 25%. On pyrolysis, sugars completely disappeared. Amino acids heated alone decreased in concentration about 25% and sugars heated alone decreased approximately 20 to 55% on pyrolysis. A sugaramino acid mixture simulating beef diffusate suffered greater losses in concentrations Of amino acids on pyrolysis than did the diffusate. No pattern of changes in amino acid or sugar Concentrations was detected to account for the aroma of roast meat on pyrolysis. In beef diffusate, sugars appear to be limiting and a portion of the amino acids remains after pyrolysis. When excess sugar is added, free amino acids disappear completely and the ratio of the amount of glucose disappearing to amino N disappearing levels off at about 4: 1.