The processing industry has also been driven by ever increasing consolidation, which has seen more and more small and medium sized operations either merge or being swallowed up by larger companies.

These larger companies and bigger operations are being met with demands from their customers for increased output with strict portion and quality control.

There are also new legislative and food safety demands being placed on the processor from authorities to meet new and ever tighter food safety and hygiene regulations.

At the same time, the processor is also faced with a shrinking workforce that is less skilled.

To achieve all these goals and to meet all these demand, the processor is turning to more and more automation on the processing line and in most cases, turn–key, complete line systems that can handle processing from the arrival of the live birds through to packaging and dispatch.

The quality, appearance and marketability of the end product are affected at every stage of the poultry processing line and this starts at slaughtering.

Delivering a Clean Product

The slaughtering department has to deliver a clean product ready for evisceration and further processing and problems that are encountered in slaughtering will have a greater effect further down the line.

At the start of the slaughter process, whether the stunning is by electric shock or through gas, the quality of the meat can be affected by the quality of the stunning process.

When the stunning is conducted through electric shock, the head of the bird passes through a water bath and electrodes in the water bath and on the shackles complete the electric circuit.

According to the Dutch poultry processing equipment company, Meyn, if a high frequency stunning system is applied, the current runs along the surface of the product, decreasing the haemorrhaging and reducing the damage to the carcass and improving meat quality.

Birds may also be killed by exposure to appropriate anoxic gas mixtures for durations that ensure that they die before they are bled.

Controlled atmosphere stunning works by starving the brain of oxygen, thereby resulting in death. The permitted gas mixtures are designed to induce loss of consciousness without undue distress. Birds can, in some systems, be placed in the gas chamber whilst they are still in their crates, thus reducing the amount of handling stress. Moreover, they must be dead by the time they are shackled, preventing the discomfort of shackles and the distress of inversion on the poultry line.

If the birds are electrically stunned, they can then travel through to an automatic neck incisor, where the killing takes place, on the same line on which they passed through the stunner. The advantage of an automatic process over previous hand slaughter methods are not only speed, but also that the incision on each bird can be precise to allow the correct bleeding, which again maintains the meat quality and also has animal welfare advantages.

Electrical Stimulation Speeds Process to Deboning

Following slaughter, many automatic slaughter lines electrically stimulate the carcass to speed up the maturation process to the stage where the carcass can be deboned. The carcass stimulation removes the need to keep the carcasss in a chill room away from the processing line until they have matured for deboning.

According to Meyn, a stimulation time of 32 seconds will produce a tender fillet within two hours and 45 minutes following slaughter.

As the carcasses remain on the line following electrical stimulation, they can then pass straight to the scald tanks to prepare them for defeathering and hock and feet cutting.

In the past, the evisceration was a long, slow and labour–intensive process but with automation, the process has become fast and able to handle high capacity with little labour and at the same time, increase biosecurity and hygiene. The quality and speed of the evisceration of the birds can have a direct effect on the stages down the line where further value is added through cut-up and deboning, because it is the stage that provides the basic raw material for value–added products.

During the process, the carcasses are prepared and cleaned and on some lines, washed and even disinfected to ensure a highly safe commodity product is presented for further processing. The ability of the machines at the various stages of the evisceration and cleaning process also to clean themselves prevents the possibility of cross–contamination.

The giblets can be harvested automatically for further use and processing and the automation also allows full traceability of batches of birds from the time they enter the plant through to further processing.

Following the evisceration process, carcasses can then be automatically rehung on a new line to take them through chilling in preparation for the cut up and deboning stage.

Gaining Maximum Yield in Cut–up and Deboning

The greatest value to the chicken carcass is added in the cut-up and deboning stage of processing and it is at this stage that maximum yield has to be achieved.

Both retailers and food service customers are now demanding specific cuts for specific products and the processor can now meet these high demands through automatic systems that precisely carry out the same cutting operation time after time, at high speed and with little need for highly skilled labour.

Automated machines can meet the demands of food service operators that require a carcass in eight or nine pieces, trimmed with fat cut off and dark meat separated in large quantities. The lines can portion product and debone everything from breast meat to legs and thighs and at the same time scan the products for particles of bone.

The systems also automatically reject product that might have bone fragments or might not meet the weight specifications helping to ensure complete quality control to achieve optimum yield. Automatic grading of product and data capture along the line give full traceability and modern logistics systems linked to the automatic processing can also identify and order specific product for specific customers.

New and developing automated processing systems are now allowing companies to meet the growing and changing consumer demands for innovative products and, at the same time, increase their margins and profitability.

May 2012