Proximate and fatty acid composition of meat from rainbow trout (Oncorhynchus mykiss W.) after dietary supplementation with black pepper (Piper nigrum L.) extract

Abstract

The study was aimed at assessing the effect of dietary supplementation with black pepper (Piper nigrum) on the chemical and fatty acid composition in the meat of rainbow trout (Oncorhynchus mykiss W.), farmed in a recirculating system.
 Rainbow trout were distributed in two groups – experimental fed 1% powdered extract from black pepper (BPE) and control (C) fed without black pepper extract. After the end of the experiment, 6 fish from each group were euthanized, filleted and deboned. The 1% BPE in rainbow trout feed reduced meat water content and increased dry matter percentage and fat content. The fatty acid profile of rainbow trout meat was beneficially influenced by the dietary BPE supplement. The SFA percentage was statistically significantly decreased whereas contents of UFA, MUFA, PUFA and n-3 were considerably higher. No consistent effect was noted with respect to n-6 fatty acids. The improved PUFA/SFA and n-6/n-3 ratios in the supplemented group showed that the tested feed additive had a favourable effect on fatty acid content of rainbow trout meat. Both ratios were within the range, beneficial for human nutrition: > 0.4 and < 5, respectively.