Cut and Dried
April 1, 2008
EFFICIENT WATER MANAGEMENT
Cut and Dried
By Tom Wray, associate editor
Water use and efficiency become more important as the industry grows and resources change.
Water is a requirement for any meat-processing operation. How it’s used may differ depending on if the meat processed is beef, pork or poultry, but it is a needed resource for any system.
It’s also a resource whose availability and quality has become more important and harder to attain. Companies must work to find the best balance between efficiently using the water available and ensuring that food safety is kept at a high level.
“There will probably always be an inherent conflict between water efficiency and food safety in meat processing plants,” says Willis Sneed, a project manager for HDR One Company in Omaha, Neb. “More water use doesn’t necessarily mean cleaner/safer food, but as water use is reduced there is inevitably a point at which cleanliness/food safety will suffer.”
John Starkey, president of the Tucker, Ga.-based U.S. Poultry and Egg Association, agrees that food safety is the highest priority. A facility must use enough water to get the job done, but beyond that, it’s how the water is used that makes the biggest difference.
The amount of water doesn’t necessarily change between processing the different species of meat.
“Actually, the amount of water used (pounds water used per pound of meat or poultry produced) is very similar between the species,” says Starkey. “Additional cut-up or processing operations will increase water usage.”
Much of the water used at poultry plants is actually reused, Sneed says.
Starkey expands by saying that water is re-used in virtually every poultry plant, with the feather flow away system that uses screened wastewater to flush feathers to feather recovery as an example of one such part of the reuse. Most of the re-uses are non-contact with product. In recent years, some facilities in drought or water -restricted areas have invested in systems that purify used water sufficiently to allow product contact, with chiller water recycle systems being the most obvious example.
“This is probably dueto the fact that this has always been how it has been done in the poultry industry — it is in their culture,” he continues. “For example, final chill tanks are typically used in poultry plants, where scald tanks are commonly used in pork plants.”
Sneed says that the pre-washing of hide-on carcasses at beef plants is becoming more common for sanitation reasons and it increases water use in those facilities. In the past, little water was used on the “dirty side of the kill” at beef plants, which severely limited the amount of water that could be reused at a beef plant. However with the new pre-washing of hide-on carcasses that is becoming more common at beef plants, there are probably now more opportunities for water reuse at beef plants.
Water reuse can also done on the “dirty side of the kill” in pork plants, he says. At two U.S. pork plants, approximately a third of the treated wastewater effluent is further treated with processes similar to a potable water treatment plant, and reused on this side of the kill. This water is used before the carcasses are cut open and washed with water before they are opened. This process was developed to help reduce the need for more water.
“It’s important to remember that while poultry (and other meats) processing is a big ‘user’ of water, plants are not a big consumer of water,” says Starkey. “Over 90 percent of the water used in a plant is treated to acceptable environmental standards and returned to streams for others to use.”
Sneed adds that certain operations can be taken off the line or restricted. For example, chitterling and stomach processing in pork plants, typically consume a lot of water. Where or when water is scarce, chitterling processing is often curtailed or eliminated and, in extreme circumstances, stomach processing might even be curtailed or eliminated.
Other techniques can help reduce the need for using water at all.
“Irradiation has been proposed, and is used to some extent, as a means of producing safe food and should probably result in good water efficiency,” says Sneed. “Even at those plants, however, I suspect the approach is to produce as clean a product as possible and then further improve its cleanliness/safety through irradiation. However, rightly or wrongly, there appears to be concern on the part of at least some people regarding the long-term effects of this process on the consumer.”
Some methods of water efficiency deal directly with the water as it’s used. Sneed says that more water meters are being used in various areas and even with specific pieces of equipment. This allows collecting water use data for each of these different areas and at different times during the day. For example, how much water is used during production, versus during sanitation and even water consumed during an idle shift. This information can be collected in one location so that it can be reviewed to see if water use is up or down and, if so, determine why this has happened.
Starkey says other tools such as automatic water pressure regulators and on/off electronic eyes on wash stations also contribute saving water.
As with almost every other aspect of processing, training plays an important role in water efficiency. Starkey states that management of the resource, including employee training, has always been important in water efficiency. He says that water usage varies by a factor of about three across the industry. The plants that are on the lower end of that scale have a mindset to always evaluates water use.
There are some complications when handling the training, however. “One complication is that many packing plants have high employee turnover rates,” says Sneed. “Therefore, new employees have to continually be trained in these processes, plus the normal refresher instruction for existing employees. Reducing water use in the short term is easy; sustaining it beyond four months is far more difficult.”