Determination of Reaction Progress in the Enzymatic Hydrolysis of Seafood Processing Byproducts: A Simple Alternative to the Degree of Hydrolysis

In many areas of food processing it is desirable to reduce the length of protein molecules. The two most commonly used methods employ either inorganic acids or proteolytic enzymes to cleave peptide bonds between adjacent amino acids. Proteolytic enzymes can reduce the viscosity of aqueous protein mixtures as well as the volume of insolubles. In the Alaskan seafood industry, liquification of processing byproducts by protein hydrolysis would be convenient if there was a simple and reliable method to gauge the progress of the reaction. Laboratory methods to quantify the degree of hydrolysis are expensive, time consuming and demand operators trained in analytical techniques. The biuret protein method uniquely shifts color from blue to purple in the presence of proteins (longer chains of amino acids) and from blue to pink in the presence of hydrolysates or the peptide results of proteolytic action.