Many studies have been carried out with respect to packaging methods and temperature conditions of beef. However, the effects of packaging methods and temperature conditions on the quality characteristics have not been extensively studied in low-grade beef. Low-grade beef samples were divided into 3 groups (C: ziplock bag packaging, T1: vacuum packaging, and T2: modified atmosphere packaging (MAP), CO2/N2 = 3:7) and samples were stored at 4°C for 21 days. The water-holding capacity (WHC) was significantly lower in T1 than in the other samples up to 14 days of storage. The thiobarbituric acid reactive substances and volatile basic nitrogen values were significantly lower in T1 and T2 than in C after 7 to 14 days of storage. The total bacterial counts were significantly lower in T1 and T2 than in C after 14 days of storage. In a sensory evaluation, tenderness and overall acceptability were significantly higher in T1 and T2 than in C at the end of the storage period (21 days). We propose that the MAP method can improve beef quality characteristics of low-grade beef during cold storage. However, the beneficial effects did not outweigh the cost increase to implement MAP.

This study was carried out to determine the effects of tomato powder (TP) on cooked pork patties during storage at 10±1°C in the dark. The total phenolic and flavonoid contents of TP extract were 26.22 mg gallic acid/100 g and 3.52 mg quercetin/100 g, respectively. The extract of TP showed a potential antioxidant activity in the DPPH radical-scavenging assay (EC50 = 16.76 μg/mL). Pork patties were manufactured with 0.25% (T1), 0.5% (T2), 0.75% (T3) and 1.0% (T4) TP in a basic formula (C). The pH and volatile basic nitrogen (VBN) values of T2, T3 and T4 patties were lower (p<0.05) than the C patties during storage. Increased concentration of TP in meat patties decreased (p<0.05) the 2-thiobarbituric acid reactive substances (TBARS) and total plate count (TPC) values at d 7 of storage. Tomato treated-patties had lower (p<0.05) values for lightness (L*), but higher (p<0.05) values for redness (a*) and yellowness (b*) at d 3 and 7 of storage compared with the C. In the case of sensory evaluation, the scores of colour, flavour and overall acceptability of T3 and T4 patties were higher (p<0.05) than those of the C patty after 3 or 7 days of storage.

The individual and interactive effects of Schisandra chinensis powder (SCP) and sodium nitrite additions on color, pH, water holding capacity, residual nitrite, 2-thiobarbituric acid reactive substances (TBARS), volatile basic nitrogen, texture properties, fatty acids, amino acids and sensory evaluation of cooked pork sausages were investigated after 20 d of storage at 4°C. The powders (0, 0.5 and 1.0%) were added to sausages either alone or in combination with nitrite (0 and 100 ppm). SCP added-sausages showed lower L* (lightness) and W (whiteness) values, and higher b* (yellowness) values than sausage containing no nitrite, and exhibited the highest a* values at a 0.5% addition (p<0.05). Residual nitrite and TBARS values were found to be significantly reduced as the addition levels of SCP increased (p<0.05). As the addition of SCP increased, the sausage showed gradually decreased brittleness, cohesiveness, springiness, gumminess and chewiness, while adhesiveness increased. Polyunsaturated fatty acid, n-6 and n-6/n-3 fatty acid ratio concentrations were significantly higher in sausages containing SCP (p<0.05). The addition of SCP to sausage significantly (p<0.05) increased the ammonia content (by 0.5% SCP) and aromatic amino acid concentrations (by 1.0% SCP) (p<0.05). Inclusion of SCP in sausage meat resulted in a significant deterioration in quality characteristics of flavor, springiness, juiciness and overall acceptability (p<0.05). As expected, the observed changes in a*, W, pH, shear force, texture property, TBARS, fatty acid, amino acid and sensory score of sausages, depended on the rate of addition of nitrite (p<0.05). These results suggest that SCP addition is not an effective way of improving the sensory evaluation of sausages, but may beneficially affect TBARS, nitrite scavenging activity, fatty acid and amino acid content in pork sausages.