Slaughter

The use of technology can significantly improve the efficiency and productivity of any processing plant. AMPC and MLA's research and development activities in this area aim to improve the effectiveness of slaughter tasks while reducing the cost to the processor.

Automation of a number of tasks is a key focus of AMPC and MLA’s processing efficiency program. For all processing plants, automated solutions must be able to accommodate a wide range of product variation and, where possible, perform multiple tasks to be cost effective. 

Automated solutions must also be manufactured to fit in the often limited floorspace available on the plant floor, which have traditionally been designed to make manual tasks efficient. 

Both beef and smallstock processing are physically demanding. In the case of beef this is due to the size of the animal, while in the case of smallstock, the high throughput of plants makes slaughter tasks very demanding. 

General slaughter and processing tasks include:

  • stunning and bleeding
  • immobilisation
  • stimulation
  • rodding and sealing the weasand
  • skin and hide removal and preparation
  • trimming and evisceration

Stunning and bleeding

Humane stunning and slaughter of animals is essential and a priority for processing plants in Australia.

The type of stunning method used during the slaughter process can affect meat quality either through pre-slaughter stress or blood removal. Occupational health and safety, animal welfare and ritual slaughter requirements are also important factors during the stunning and bleeding phases of the slaughter process.

Immobilisation

During slaughter and dressing, carcases may be subjected to a range of electrical inputs. These are used to:

  • limit the danger to workers from kicking
  • assist rapid bleeding
  • prevent broken backs from hide pulling

Each of these applications may require a specific current, waveform and frequency. Use of incorrect electrical parameters may result in damage to the carcase, poor meat quality and safety risks.

Devices that apply electrical inputs at various points on the slaughter floor are used extensively by Australian processors.

Stimulation

Electrical stimulation can be applied to carcases to encourage a rapid fall in muscle pH, which allows carcases to quickly cool without 'cold' shortening of muscle fibres and subsequent toughening. 

Rodding and sealing the weasand

Effectively sealing the contents of the stomach is the objective in this phase to eliminate contamination of the carcase. The contents of the weasand or oesophagus is directed down with a rod and a clip is used to isolate the stomach contents. 

Skin and hide removal and preparation

Sheepskins and beef hides are one of the major sources of carcase contamination and are also valuable co-products. As such, it is important to keep the hides clean prior to skinning and remove the skin or hide efficiently and with minimal damage.

Trimming and evisceration

AQIS has prescribed a zero tolerance for the carcase contaminants ingesta, faeces, milk and urine. Trimming is an acceptable action to remove contaminants, excess fat and tidy the carcase.

Careful evisceration of a carcase ensures internal organs can be removed intact, thereby reducing contamination and protecting the valuable co- product, offal.

The spinal cord in a carcase is a 'specified risk material' and may contain large amounts of prions in infected animals. The carcase must be split down the centre of the spine so that the split doesn't damage the spinal cord or any of the primal cuts.