Vacuum meat tumblers

Tumblers are used for the processing of meat products such as whole-muscle or reconstituted hams. Such machines resemble in principle a drum concrete mixer. A rotating drum with steel paddles inside slowly moves the meat pieces thus causing a mechanical massaging effect. This mechanical process is assisted by the addition of salt and phosphates to achieve equal brine distribution and liberates muscular protein from the meat tissue (protein extraction). The semi-liquid protein substances join the meat pieces firmly together during later heat treatment. For hygienic reasons it is important to place the tumbler below 10°C to avoid excessive microbial growth during lengthy tumbling times (more then 4 hours or even over night). In specific cases it is recommended that the tumbler should be operated refrigerated  or inside a cold room below -1°C, as these temperatures are best to extract as much soluble protein as possible from the muscle meat.