The effect of wild thyme extracts on quality and shelf-life of cooked sausages Possibilities for the application of thyme extract as an antioxidant in sausage manufacturing

Supercritical fluid extraction (SFE) was used as environmentally-friendly procedure for the preparation of wild thyme by-product extracts (SFE1 and SFE2). The extracts effect on pH, color, residual nitrite content, lipid oxidation (TBARS value) and total plate count (TPC) of cooked sausages produced with 50 mg/kg of sodium nitrite was investigated. Five batches were produced: T1: 100 mg/kg of sodium nitrite; T2: 50 mg of sodium nitrite; T3: 50 mg of sodium nitrite and 0.150 mu L/g of SFE1; T4: 50 mg of sodium nitrite and 0.150 mu L/g of SFE2; T5: 50 mg of sodium nitrite, 0.075 mu L/g of SFE1 and 0.075 mu L/g of SFE2. Thymol and carvacrol were the most dominant bioactive compounds in both types of extracts. SFE1 and SFE2 improved redness and decreased residual nitrite content. The lowest level of lipid oxidation and microbial growth were assessed in the sample treated with 0.150 mu L/g of SFE2. Therefore, the results of this study showed significant antioxidative activity of wild thyme by-product extracts, and its potential as an effective sodium nitrite replacement in cured meat products.