The subject of the research study constituted muscles of rainbow trout bred in various regions in Poland. The fish used in the study originated from trout farms located in the voivodships (provinces) of Małopolska, Silesia, Świętokrzyskie, and Warmińsko-Mazurskie. The effect of farm location and type of farming on the chemical composition, health quality, and technological usefulness of fish was analyzed. The research included the determination of the following parameters in the muscles of fish: slaughter yield, content levels of water, protein, fat, mineral compounds in the form of ash, arsenic, lead, mercury, and cadmium. The slaughter yields of fish as well as the content of protein and mineral compounds in tissues were similar in all the farms tested. The muscles of fish from the farm located in the Małopolska Voivodship contained the lowest amount of water (71.07%). The flesh of fish from the Świętokrzyskie Voivodship had the highest content of lipids (7.4%); this was linked with the method of feeding the fish. In none of the analyzed muscle samples of trout from various farms, the content of heavy metals was found to exceed the allowable limits thereof as indicated in the Regulation of the European Commission No. 1881/2006. Furthermore, no impact of the feeding method or of the geographical location of farm was found on the heavy metal contamination level in the tissues of the fish studied.
trout (Oncorhynchus mykiss), slaughter yield, basic chemical composition, heavy metals