Abstract
The objective of this work was to study the oxidative stability of organic dry fermented probiotic sausages during long-term storage (6 months). Four test samples were prepared: sample A - control sausage, sample B - with 0.05% addition of sodium ascorbate, sample C - with addition of Lb. casei LOCK 0900 (2x106 CFU/g) probiotic strain, 0.6% of glucose, and 0.05% of sodium ascorbate, and sample D - with 0.05% of sodium ascorbate, probiotics, and 0.6% of lactose. The study covered evaluation of the ripening process (21 d) by evaluating loss in the sausage weight. The pH value, oxidation-reduction potential, TBARS values, acid number, peroxide number, browning index after ripening (0) and after 2nd, 4th, and 6th month of chilling storage were identified. The total colour difference of sausages subjected to 3 h exposure to fluorescent light, texture parameters, and count of lactic acid bacteria (LAB) were identified after ripening (0) and after 6 months of storage. It was observed that an addition of probiotic bacteria and glucose (sample C) contributed to a significant decrease in the pH value and water activity in the sausage directly after ripening and during the entire chilling storage period. In samples with probiotics the option with glucose had a lower (P≤0.05) pH value by ca. 0.5 unit as compared to the sample with lactose. Significantly higher (P≤0.05) values of TBARS were observed in samples with probiotics as compared to control samples. The greatest oxidation stability during the entire chilling storage period was found in the sample with sodium ascorbate. Among samples with probiotic strain, the sample with glucose had the lowest peroxide number value (0.58-3.56 meqO2/kg) and TBARS (1.10-2.08 mg MDA/kg) but also the greatest colour stability during exposure to light. The order of decline in oxidative stability was: sample B > sample C > sample D > sample A.
Co-encapsulation of vegetable oils with phenolic antioxidants and evaluation of their oxidative stability under long-term storage conditions