Effets de la nature du bois de fumage (Eucalyptus, Olea) sur l’amélioration des propriétés nutritionnelles et sensorielles, et sur l’aptitude à la conservation de la« Sardina pilchardus »

Abstract

The present sttudy aims to investigate the effects of the nature of wood for smoking (Eucalyptus, Olea) on improving the sensory properties, and nutritional quality of fish « Sardina pilchardus ». Smoking of fish have made in traditional smokehouse at temperature of 4°C/30-40 min. The research was carried out using two factors namely ; the type of wood (Eucalyptus golobulus, Olea europeen) and shelf life at refrigeration temperature of 4°C (7J) and freezing temperature of -18°C (20J). The compound phénolique leaves of Eucalyptus a little high compared to leaves of Olea europeen, represents : 39, 33 mg gallic acid equivalent / g of dry matter respectively. According to the DPPH test results that the extract of Eucalyptus showed better DPPH radical anti inhibitory activity • with the lowest IC50 (4.31 mg / ml) followed Olea's extracts relative to DPPH radical anti inhibitory activity • either: IC50 (6.16 mg / ml). The biochemical analyzes of fish concerned the evolution of nutritional compounds (dry matter, moisture, fat and protein), and evolution in pH and the index of lipid peroxidation (TBARS). The result of this experiment show the nature of the wood and the shelf life had a significant effect (P<0.05) on the dry matter, moisture, fat and index of lipid peroxidation. It can be concluded that the liquid smoke preserved samples tested better against the increase in humidity. From the resultts obtained, it appear that lipolysis was delayed from samples traditionally smoked and preserved in temperature at +4°C and -18°C especially for fish smoked with Eucalyptus which were reduced of 9.60 %, is the product for which a gain MDA it was the lowest 29.82%. The composition of the wood used and the control group (liquid smoke), did not prevent acidification of smoked fish during storage at 4 °C (7J), -18 °C (20J) for the samples studied, besides it was a great decrease of pH in samples smoked with liquid smoke represents 3.07%, 6.48% respectively. To evaluate the sensory test, we studied : color, textur, juiciness, flavor, smell. In conclusion, samples smoked with Eucalyptus was judged : clear, less juicy, wet, very good , pleasant)