Impact of a Saponin-Free Quinoa Extract on Microbial Spoilage in Chilled Lean and Fatty Fish

Abstract

Inhibition ofmicrobial activity in chilled fish was investigated. For it, an aqueous/ethanolic saponin-free quinoa extract was added to the icing system and applied to lean (megrim, Lepidorhombus whif.fiagonis; 0.03 and 0.12 g lyophilised quinoa/L icing solution) and fatty (Atlantic chub mackerel, Scomber eolias; 0.05 and 0.20 g lyophilised quinoa/L icing solution) fish. Microbial development was monitored for a 13-day chilled storage period by microbial and chemical indices. An inhibitory effect (p < 0.05) of the quinoa extracts present in the icing systems on microbial development in megrim (aerobe counts, pH and free fatty acid value) and mackerel (aerobe, psychrotroph, proteolytic and lipolytic counts; pH and free fatty acid values) was observed when considering the most concentrated presence of quinoa in the icing system. A novel icing system is proposed to obtain improvement in the quality ofboth lean and fatty fish species during commercialisation under chilled conditions