A new process for production of high energy fish feed, evaluated by experimental design and chemical analyses

A new process for drying and coating fish feed containing fish oil has been developed. The process is based on an interchange between water and fat inside the feed pellets, using a high temperature oil bath containing marine oil. The effects of the process on the oil quality were evaluated using experimental design and multivariate methods. Fish oils are sensitive to oxidation when they are exposed to air or heat. The ω-3 fatty acids in the marine oil were suspected to be unstable when heated. An accumulation of the oxidation products in the fish oil-bath during the heat treatment was also anticipated. However, chemical analysis of the oil and feed before and after the process showed that the oxidation of the oil related to the oil quality parameters were stable during the process. In order to achieve relevant data from the process, experimental design was utilized in this work. Use of experimental design and multivariate techniques is cost effective and give more information compared to the traditional way of doing experiments by changing one variable at a time.