[Bioassay of rainbow trout (Oncorhynchus mykiss) pigmentation using ancho chili (Capsicum annuum) extracts].

Farming of trout requires a finishing diet containing pigments such as astaxanthin and canthaxanthin so that they may achieve a pink tissue coloration similar to that of wild trout. The production of synthetic pigments is not enough so that the requirements of the aquaculture industry are not met, besides having a high cost. Thus, the objective of the present study was to evaluate the deposition of saponified and esterified chili (Capsicum annuum) extracts in the skin and muscle of rainbow trout (Oncorhynchus mykiis). The experiment consisted of three treatments with the inclusion in the finishing diet of saponified and esterified chili extracts and of astaxanthin, respectively. Each treatment was carried out with 150 organisms with an average weight of a 150 g and done in duplicate. The results showed that both the saponified and esterified chili extracts pigmented the skin and muscle of rainbow trout, although the pigmentation effect was less red than that produced by the astaxanthin control.