Some engineering properties and nutrient composition of selected pelletized fish feed in Nigeria

Abstract

Abstract This research work is aimed to study the engineering properties (Physical, Thermal and Mechanical), and nutritional qualities of selected pelletized fish feed in Nigeria. This is to provide a database of engineering properties of fish feed pellets in Nigeria, which can be required for further handling and processing operations. Three locally produced feeds in Nigeria (Kwara P1, Ondo P2, and Edo P3) were selected. The engineering properties analysed include unit density, bulk density, expansion ratio, colour, sinking velocity, water stability, water absorption index, water solubility index, pellet durability index, thermal conductivity, resistivity and diffusivity. The extrudates and pellets were subjected to nutritional composition analyses, which include: crude protein, crude fat, total carbohydrate, ash and crude fibre, Potassium, Phosphorus and Calcium. The unit density, bulk density and expansion ratio of the pellets ranges from 407.08 – 518.36 kg.m−3, 267.33 – 271.93 kg.m−3 and 12.73 – 16.40 %, respectively. The pellet durability index and water stability ranges from 41.07 - 68.60 % and 12.40 – 35.96 mins but P2 had the highest expansion rate (25.55%). The Potassium, Zinc, crude fibre and thermal properties had no significant effect on the feeds at p-level of 5%. The data obtained from this study creates a reference line for the design and development of handling machines, and storage facilities.