Revealing and controlling the hidden losses of processing

In many chicken processing plants camera systems are installed at strategic locations to monitor, in real-time, the stages of the entire production process. These cameras are usually placed to keep track of the storage room for live chickens, the hanging of chickens on the overhead conveyor, evisceration, chillers, packaging, cold rooms and shipping.

The monitor screens are usually located in the offices of the plant manager and general manager, where a trained observer focuses on the following aspects:

• That in the storage room there are chickens in stock to guarantee that the production process never halts.

• Chickens are hung properly on the overhead killing conveyor.

• The evisceration personnel are working normally.

• That at the chillers, there is not a large number of chickens on the conveyor belt. Bottlenecks affect temperature and water uptake of the carcasses.

• At packaging the chickens are being bagged and clipped according to the flow coming from the chiller.

• In the cold rooms, the baskets with chicken must enter the room as soon as possible in order to prevent a rise in temperature in the carcass and weight loss. In the shipping department, once chickens are weighed on the scale, they should be immediately loaded onto the truck to prevent a rise in temperature.

Altogether, the process monitoring operation aims to verify that the slaughter and processing of the chickens are developing in accordance with the slaughter programme.

Synchronised operations
On the other hand, it should be borne in mind that poultry processing is a set of synchronised operations that adds and subtracts weight to the final product. For this reason, the real time monitoring of the process and attendant activities allow the stages where losses occur to be isolated and therefore offers solutions to controlling those parameters. These operations are mentioned in Table 1. Obviously in most stages the chicken carcass loses weight. However, many plants are not properly monitored during processing because the management’s attention is focused on implementing the programme of slaughter within the normal working day (shift). As a consequence, their concern is ensuring other aspects such as:

• An adequate supply of potable water.

• The work force completes its set jobs.

• Ice supply is well-stocked.

• An adequate supply of baskets for the packaging of processed chickens.

• Clips stock for clipping bags is correct.

• Adequate number of bags for packaging birds and giblets.

• Physical and sanitary quality of processed poultry is consistent and within the parameters of the company.

Therefore, since the success of this activity is to account for every gram of edible product, it is necessary to monitor in real time if the normal loss occurring during this process is within allowable limits.

Monitoring all stages
Taking advantage of the effectiveness of the monitoring system through the use of cameras, it is necessary to extend this coverage to places where it is known that losses occur. Putting this tool for monitoring yield of chickens into operation, allows for completing the monitoring activities of the process. Not only verifying that the process develops normally, but also that the losses that do occur, are within the control parameters.

The following are examples of stages that should be monitored during processing:
Stunning. Chickens falling in the tub.
Bleeding tunnel. Chickens falling on the floor. If not collected quickly, they become damaged and must be sent to the rendering plant.
Scalding. All shackles must have chickens before and after leaving the scalder. All birds that fall in the tank will be over-scalded. As a result, chickens will be condemned and also need to be sent to the rendering plant.
Plucking. Birds may fall on the floor or covering grills located on the floor channels that carry waste water. If not collected as soon as possible, they become damaged and must be condemned. Additionally, there is a risk that they will be covered with feathers and as a result need to be taken to the rendering plant.
Evisceration. Chickens and offal fall on the evisceration trough. At the exit of the trough, there are some giblets, gizzards, livers and hearts mixed with offal. For sanitary reasons, everything that falls into the trough cannot be recovered. The fall may be caused by deficiencies in the infrastructure or by inappropriate working methods.
Packaging. Birds and their giblets are falling into different places of this section. If these are packaged, it is possible that the health inspector approves returning them to production. If not, they will be confiscated and sent as waste to the rendering plant. The success of such a monitoring programme with the use of cameras, will depend on the degree of care with which the screens which show images of different review sites will be supervised.

Flight controllers
Process monitoring can be compared to the work done by air traffic controllers, who are in contact with the pilots during the flight to make sure they reach their final destination. If they find that an aircraft went off the flight path, they immediately inform the pilots to carry out the appropriate adjustments.

Similarly, if during processing it is detected that products are being lost somewhere in the stages mentioned above, the section supervisor needs to be notified immediately in order to review and take corrective action as soon as possible. This new monitoring tool is very useful, especially in high speed processes where one bird per second is normal. Without proper attention to these losses of product in real-time, the daily yield of processed chickens is significantly affected. In addition, the expenses increase which could jeopardise the competitive position of the company.