Co-Immobilization of Trypsin and Lysine -α- Oxidase For the Quantification of Lysine in Casein Hydrolysate. Evaluation with a Biosensor.

BACKGROUND/AIMS: The quantification of amino acids in the dairy industry is necessary for quality control and for the formulation of functional foods. Thus, the development of enzymatic biosensors requires a detailed study of enzyme kinetics. Parameters such as KM and Vmax are necessary to optimize the sensitivity and specificity of the biosensor. METHODS: The enzyme immobilized on nylon and yucca bipolymer membranes was studied to evaluate possible interferences in the amperometric sensor. RESULTS: The sensor developed based on enzyme kinetics proved to be a reliable, sensitive, and low-cost alternative for determining lysine in dairy products. Its performance, comparable to HPLC, together with its low environmental impact, positions it as a useful tool for quality control in the food industry. CONCLUSION: An enzymatic biosensor capable of quickly, accurately, and economically quantifying lysine in casein hydrolysates was developed. Its high sensitivity, enzymatic stability, and low environmental impact make it a viable and comparable alternative to HPLC for quality control in dairy products.