Impact of processing on the antioxidant activity of a microorganism-enriched fish feed and subsequent quality effects on fillets of rainbow trout (Oncorhynchus mykiss)

Pike-Perch (Sander lucioperca) and Rainbow Trout (Oncorhynchus mykiss) Fed with an Alternative Microorganism Mix for Reducing Fish Meal and Oil—Fishes’ Growth Performances and Quality Traits

“…For example, Øverland et al (2009) substituted fish meal with pea protein in diets for Atlantic salmon (Salmo salar) [29], whereas Barrows and Frost [30] used co-products from the nut industry, algae, and invertebrate meals in diets for rainbow trout (Oncorhynchus mykiss) [30]. The sensory aspects such as the variation of the fillet color or the skin color are typical parameters that need to be considered, as well [13,31]. However, the variations of taste, flavor, and texture of the fillets, especially, of rainbow trout (Oncorhynchus mykiss) and pike-perch (Sander lucioperca) were hardly taken into account and accordingly have not been described yet comprehensively.…”

“…They are low-PUFA freshwater fishes and important for human nutrition. Schafberg et al (2020) already showed in a recent study the effects of an innovative feed on antioxidant activity with regard to the course from raw materials over feed production into the fillets of rainbow trout [31]. In that study, three diets were compared: a commercially available industrial (standard) diet, a control diet, and a new feed mix.…”

“…In that mix, fish meal and oil content were reduced by half (compared to the control diet). For preventing nutrient deficiency, a mixture of the microorganisms Crypthecodinium cohnii, Arthrospira sp., and Rhodotorula glutinis was used [13,31]. R. glutinis was chosen as the new lipid source.…”

“…Instead of fish meal, Arthrospira sp. was used as the new additional source of proteins [13,18,31]. In order to ensure sustainable aquaculture, microorganisms were cultivated in biotechnological processes [18,33,34].…”

“…In order to ensure sustainable aquaculture, microorganisms were cultivated in biotechnological processes [18,33,34]. Schafberg et al (2020) showed that the microorganism-based feed mix led to healthy fish, which were comparable to conventionally fed fishes and led to the accumulation of carotenoids and other antioxidants in the fish fillets [31].…”