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Quality changes in frankfurter sausages with yam (Dioscorea japonica) powder added were investigated during their storage at 10°C for six weeks. The sausage samples were prepared using four concentrations of yam powder: 0% (C), 0.5% (T1), 1.0% (T2), and 2.0% (w/w) (T3). After the addition of yam powder, the crude protein contents decreased, but the crude fat and carbohydrate contents increased. The thiobarbituric acid values during the storage of the frankfurter sausages were lower in the samples with higher yam concentrations. Over the storage period, the volatile basic nitrogen values increased with the increase in the amount of added yam. With the increase in the yam concentration, the L* and a* values tended to decrease, whereas the b* value increased. The instrumental texture analysis showed that the hardness value decreased with the increase in the yam concentration. The first indication of sensorial quality deterioration was noticed at week 4 for T3 and at week 5 for C, T1, and T2. In conclusion, the quality and shelf-life of the frankfurter sausages were not noticeably influenced by the addition of yam powder with a concentration of up to 1.0% (w/w), but the functional and health-promoting effects of yam were positively incorporated.

Ready-to-eat chicken breasts were packaged in a multilayer, gas-tight tray with top film and various quality changes were investigated during the 24 wk of storage at 10 o C. Over the storage period, total aerobes, mesophilic aerobic and anaerobic spore formers, and Clostridium spp. were not detected above 1.0 log CFU/g (detection limit). The residual oxygen ratio in the head space of tray and pH values tended to decrease with storage time, namely from initial values of 5.7% and 6.56 to 3.3% and 6.34 at week 24, respectively. Thiobarbituric acid reactive substances and volatile basic nitrogen values increased from 0.52 mg malonaldehyde (MA)/kg and 2.1 mg/100 g initially, to 3.70 mg MA/kg and 39.9 mg/100 g at week 24, respectively. In terms of the change in meat color during storage, the samples showed a slight increasing trend of CIE a * , b * , and ∆E values over the storage period until week 24 (p<0.05). The change in brine color showed a similar trend with meat of which Hunter b * and ∆E values increased slightly during storage during 24 wk (p<0.05). The values for the transmittance degree of brine in the samples tended to decrease. Moreover, values for the absorbance degree tended to increase with storage time until week 24. The sensory scores for color, texture, odour, and flavour were evaluated below 5.0 (marketability level) after 24 wk of storage. Based on this sensory evaluation, it could be concluded that retorted RTE chicken breast could remain marketable for at least 20 wk at 10 o C.