Feed composition and oxidative stability of rainbow trout during frozen storage

摘要

The rainbow trout (Oncorhynchus mykiss) farming industry has increased drastically in the last few decades reaching 600 million t in 2007, with Norway and Chile being the main producers (FAO 2010). Rainbow trout are fatty fish with a muscle fat content of approximately 10 to 15 percent and are, therefore, a good source of the long chain omega-3 fatty acids, which they obtain from their diet. Indeed, feed formulations for carnivorous fishes primarily contain fishmeal (about 30 percent) and fish oil (about 20 percent), which contains high amounts of omega-3 polyunsaturated fatty acids (PUFA), as essential ingredients. However, manipulation of the feed is seen as an interesting strategy for improving sustainability and optimizing utilization of marineresources by, for example, increasing feed digestibility, improving fish performance but also reducing the dependency of the sector on costly ingredients. Increasing pressure on fish oil producers for an enhanced product, in combination with unpredictable raw material abundance make fish oil a limited and costly feed ingredient.