214 Meat refrigeration for 3 weeks in vacuum packs discoloured more rapidly and off-odours leveloped sooner than those from meat that had been hung in air for one week or vacuum packed for one week. The poorer storage stability was explained by higher initial levels of bacteria because of growth during ageing Rancidity development was only detected in the 3-week-aged steaks that were stored at 6C Studies have also shown that there is an interaction between storage and retail display. The retail display life of pork from CO2 packaged primals depends on the length of time the primals have been stored( Greer et al 1993). On appearance criteria, the display life in days is 4.60-0. 15(weeks in storage), whilst on odour criteria the display life in days is 5.03-0.17 The tenderness, juiciness and flavour of beef patties has been found to deteriorate during chilled storage with the flavour deteriorating less at 0C than at 4 or 8C(Bentley et al. 1989). Drip loss increased with storage temperature from 3.2%at 0C to 3.3% at 4C and 4.6% at 8"C Drip loss was also affected by the type of packaging with greater drip in vacuum packs than in 100% nitrogen or CO2 back-flushed packs. Total plate counts Icreased from 2.7 to 7.2 loglo cfu cm after 7 days and to 8.6loglo cfu after 1 days of storage but no effect of storage temperature or packaging type was detected 10.2.3 Cooked products The influence of temperature on the storage life of vacuum packed sliced cured meat products is shown clearly in Table 10.4 Precooked beef roasts can be stored for 28 days at 4C(Stites et al 1989). The roasts of beef chuck were prepared in vacuum cooking bags with phosphate salt and cooked to a centre temperature of 70C. They were then Table 10.4 Storage life for vacuum-packed sliced cured meat products Temperature Storage life(days) Cooked Cooked 11.5 Source: Bogh-Sorensen et al.. 1986for 3 weeks in vacuum packs discoloured more rapidly and off-odours developed sooner than those from meat that had been hung in air for one week or vacuum packed for one week. The poorer storage stability was explained by higher initial levels of bacteria because of growth during ageing. Rancidity development was only detected in the 3-week-aged steaks that were stored at 6 °C. Studies have also shown that there is an interaction between storage and retail display. The retail display life of pork from CO2 packaged primals depends on the length of time the primals have been stored (Greer et al., 1993). On appearance criteria, the display life in days is 4.60–0.15 (weeks in storage), whilst on odour criteria the display life in days is 5.03–0.17 (weeks in storage). The tenderness, juiciness and flavour of beef patties has been found to deteriorate during chilled storage with the flavour deteriorating less at 0 °C than at 4 or 8 °C (Bentley et al., 1989). Drip loss increased with storage temperature from 3.2% at 0 °C to 3.3% at 4 °C and 4.6% at 8 °C. Drip loss was also affected by the type of packaging with greater drip in vacuum packs than in 100% nitrogen or CO2 back-flushed packs. Total plate counts increased from 2.7 to 7.2 log10 cfucm-2 after 7 days and to 8.6 log10 cfu after 21 days of storage but no effect of storage temperature or packaging type was detected. 10.2.3 Cooked products The influence of temperature on the storage life of vacuum packed sliced cured meat products is shown clearly in Table 10.4. Precooked beef roasts can be stored for 28 days at 4 °C (Stites et al., 1989).The roasts of beef chuck were prepared in vacuum cooking bags with phosphate salt and cooked to a centre temperature of 70 °C.They were then 214 Meat refrigeration Table 10.4 Storage life for vacuum-packed sliced cured meat products Temperature Storage life (days) (°C) Bologna Smoked Cooked Cooked sausage fillet pork loin pork loin 12 7 – 21 – 8 11.5 9 33 16.5 5 21.5 10 66 31.5 2 33 11.5 78 52.5 0 42 22.5 141 64 -3 11 33 165 >64 Source: Bøgh-Sørensen et al., 1986