Perfil e estabilidade de aminoácidos em farinhas e rações destinadas a carcinicultura.

• Autor(a) principal: Prado, João Paulo de Sousa
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/tede/4077
• topic: Litopenaeus vannamei; Farinha de peixe; Farinha de soja; Lixiviação; Estabilidade térmica; Armazenamento; Litopenaeus vannamei; Fish meal; Soya meal; Leaching; Thermal stability; Storage; CIENCIA E TECNOLOGIA DE ALIMENTOS::CIENCIA DE ALIMENTOS

This study aimed to evaluate the profile and stability of amino acids in meals and feeds used in shrimp farming. The study was divided into three experiments. In the experiment I the percent composition and profile of amino acids in fish meal and soya meal feeds with protein levels of 35 and 40% used in shrimp farming were evaluated. Comparing the results of amino acid profile of the feeds used in this study with those determined by chemical score, it can be noted that feeds A and B were not satisfactory in the content of essential amino acids, except lysine, which showed chemical score (CS) higher than the standard. The fish meal and soya meal used in the formulation of commercial feed (RA) had amino acid profile superior to those found in meals used for obtaining commercial feed (RB). In experiment II the aim was to evaluate the stability of amino acids in commercial feeds with different protein contents subject to leaching. The feed samples were exposed to the leaching process during time period of 04, 08 and 12 hours. Analyses of degradation of amino acids were performed using an elution gradient in HPLC system. In all feeds evaluated it was found that lysine and histidine are essential amino acids which suffered less degradation processes. It is important to mention that arginine is considered an important amino acid for growth of shrimp, and that both diets with 35% protein (RB35 and RA35) had losses of 79 and 89% respectively. The results obtained in this study indicate that the leaching process significantly reduces the content of amino acids in the feeds. The physical structure of the feed does not prevent the degradation process of amino acids in the leaching process. Experiment III was to evaluate the stability of amino acids in meals and commercial feeds with different protein levels subjected to hightemperature storage. The samples were exposed to temperature of 50 C and evaluated every 5 days for 30 days. Analyses of degradation of amino acids were performed using an elution gradient in HPLC system. In all evaluated meals it was observed that valine and arginine suffered greater losses of amino acids during the experiment and histidine and alanine suffered less degradation processes. It was observed difference in the content of all amino acids studied after the exposure of feeds to the temperature of 50 º C, with reduction of the amino acid content of the feeds. The results obtained in this study indicate that meals and feeds exposed to high temperatures had their amino acid content significantly reduced.