Fatty acid composition and oxidative stability of oils recovered from acid silage and bacterial fermentation of fish (Sea bass – Dicentrarchus labrax) by‐products

Abstract

Summary Lipid quality and fatty acid compositions of fish oils recovered from fish (Sea bass – Dicentrarchus labrax) waste silages produced with formic acid (FA) and five different LAB strains (Lactobacillus plantarum (LP), Pediococcus acidilactici (PA), Enterococcus gallinarum (EG), Lactobacillus brevis (LB) and Streptococcus spp. (ST)) were assessed to ensure for the usage for human consumption. Generally, it was observed that there were no significant differences between PUFA contents (23.27–23.64%). Peroxide (PV) (2.12 meq active O2/per kg of oil) and TBA values (1.07 mg malonaldehyde (MA) g−1 oil) of fish oils from acid silage were significantly higher than those of the fermented ones (1.14–1.91 meq active O2 kg−1, 0.67–0.81 mgMA g−1 oil, respectively). Anisidine values (AV) were determined in range of 8.04–11.14 for fermented silages and 13.08 from acid silage. The highest totox value (17.33 ± 0.88) was also detected in acid silage oil whereas fermented groups gave totox value in the range of 10.40–13.88. It can be concluded that the initial lipid quality of fermented fish waste silages was better than the initial lipid quality of acid fish waste silage. Therefore, fish oils recovered from fermented silages can be used as food additives or supplements for animal and human diets.

Evaluation of the potential use of discard species for fish silage and assessment of its oils for human consumption

“…Similar results were observed of acidified and fermented sea bass by‐product silages in terms of AV of fish oils (8.04–11.14 for fish oils recovered from fermented fish silages and 13.08 for fish oil recovered from acid silage) by Ozyurt et al . ().…”

“…Ozyurt et al . () investigated oxidative stability of oils recovered from acid silage and bacterial fermentation of sea bass by products. The highest PV was found in oil of acid silage (2.12 meq active O 2 per kg of oil).…”

“…The highest totox values were detected in oils, extracted from acid silage groups as reported by Ozyurt et al . (). It was attributed to low pH, accelerating oxidation.…”

“…Accordingly, it can be concluded that using acid for the preparation of fish silage accelerated the lipid oxidation. Similar results were observed of acidified and fermented fish silages in terms of lipid stability (Ozyurt et al ., ). On the other hand, TBA values of all recovered fish oil were quite below the acceptable limit (5 mg MA per kg) for marine oils (Schormüller, ).…”

“…Ozyurt et al . () also investigated fatty acid composition and oxidative stability of oils recovered from acid silage and bacterial fermentation of fish (Sea bass– Dicentrarchus labrax ) by‐products. They reported that fish oils recovered from fermented silages can be used as food additives or supplements for animal and human diets.…”