Evaluation of storage stability of poultry by-product meal incorporated fish feed under aerobic storage condition

Abstract

The research focused on development of fish feed utilising poultry by-product meal (PBM) as a substitute for fish meal (FM) and evaluating its shelf life under aerobic packaging conditions. Initially, a basal diet (C) was formulated to meet the nutritional requirements for optimal growth of Tilapia by using FM as the major protein source. After analysing the nutritional composition of PBM, an isoproteinaceous diet (T) was formulated by replacing FM with PBM. The product was packed in HDPE bags and kept at room temperature and analysed for physico chemical and microbial characteristics for 45 days at weekly intervals. Moisture content of both C and T decreased significantly (p0.05) was found between C and T. The TBARS value of both C and T followed an increasing trend. This increase in C was not significant (p<0.01) between 28th and 35th day, and between 42nd and 45th day but that of T increased significantly (p<0.01) throughout the storage period. T consistently displayed the highest TBARS value during storage period. Tyrosine Value (TV) of both C and T also increased during storage and was significant (p<0.01) up to 42nd day of storage. C exhibited the highest TV throughout the storage period. Similarly, total viable count (TVC) of both C and T increased on storage. The increase in TVC for C was not significant (p<0.01) between 21st and 28th days, whereas that of T was significant (p<0.01) throughout the storage period. On 45th day, T exhibited highest count and was significantly different (p<0.01) from C. Throughout the 45-day storage period, no observable coliform count or yeast and mould count was noted in either C or T. The present study indicated that fish feed can be effectively prepared by utilising PBM and can be stored under room temperature up to 45 days. Keywords: Poultry by-product meal, fish meal, fish feed, storage stability