The effects of non-vacuum packaging systems on drip loss from chilled beef

This study investigated drip loss in chilled beef (hot-boned m. longissimus lumborum (LL)) under conventional packaging systems, in which a vacuum is applied, and non-vacuum packaging systems. The use of vacuum during the packaging process (vacuum packaging, CO2 atmosphere packaging) was associated with increased drip. Drip was lower in heat-shrunk vacuum packaging than in non-shrunk vacuum packaging. A slow vacuum onset had no effect on drip formation, or may have increased it. The extent of pressure reduction (vacuum; range 0-1 atm) did not significantly affect drip formation, although the standard vacuum pressure (0 atm) tended to cause more drip loss than higher pressures. The three non-vacuum anaerobic packaging systems tested were:pushed with carbon dioxide without the pressure being reduced below atmospheric (Flush), or the same system with no CO2 flush but a proprietary oxygen absorber added (Scavenger), or a combination of both (Flush/Scavenger). Storage was at -1.5 degrees C for up to 20 weeks. The Flush and Flush/Scavenger systems had considerably lower drip loss than the CAP standard system (64%, 6.5%, and 9.1% respectively), the Scavenger system had the lowest drip loss (5.2%). Drip losses generally increased with storage period, irrespective of packaging system. All non-vacuum packaging systems except the Flush system had very low oxygen levels (< 0.1% v/v). The Flush system had considerably higher levels of oxygen (0.9%) with associated browning of meat samples. All packaging systems gave a hygienic shelf-life of at least 16 weeks. At 16 weeks, microbial numbers were highest (5 x 10(6)) in the Scavenger system. The meat from all packaging systems was acceptable to taste panels even after 16 weeks of storage at -1.5 degrees C.. There were no significant differences between any of the packaging systems for any of the sensory attributes tested. The packaging systems with the best all round performance were the Flush/Scavenger and the Scavenger systems, depending on the storage-life required. (C) 1998 Elsevier Science Ltd. All rights reserved.