Thermal stability of amino acids in meals and feeds used in shrimp farming

Abstract

The Brazilian shrimp farming uses mainly commercial feed for shrimp nutrition. This choice occurs because of the advantages related to convenience and good adaptation of Litopenaeus vannanmei to feed intake. Thus, the quality of feed is a determining factor for maximum performance of the shrimp farms, making the right selection of suppliers and control of the storage conditions as ways to prevent contamination and spoilage of feed. The objective of this study was to evaluate the stability of amino acids in meals and commercial feed with different protein levels, subjected to high-temperature storage. The samples were exposed to temperature of 50 oC and evaluated every 5 days for 30 days.The analyses of the degradation of amino acids were performed using an elution gradient in HPLC system.In evaluated meals it was observed that valine and arginine were the amino acids that suffered greater loss during the experiment and histidine and alanine suffered less degradation.Significant difference was observed in the content of all amino acids analyzed after exposure of the feed to the temperature of 50 oC; with reduce in values of its amino acid content. The results obtained in this study indicate that meals and feed exposed to elevated temperatures significantly reduced the content of its amino acids.