A critical element of food safety is maintaining proper temperatures from the field to the fork. In practical terms, this means keeping produce cold enough to inhibit pathogen growth or spoilage from the time it leaves the farm or orchard until it’s in the customer’s possession. It also means cooking certain foods at high enough temperatures for long enough to be safe and maintaining prepared, ready-to-eat (RTE) foods at the proper temperatures (and keeping frozen foods cold enough to remain that way). As implementation of U.S. Food and Drug Administration (FDA) rules under the Food Safety Modernization Act (FSMA) come into play this year, maintaining quality in the cold supply chain will come under increasing scrutiny. Consumers are demanding more and varied food items year-round at supermarket and retail delis, bringing a renewed focus to temperature control, according to David Oster, CEO of PakSense Inc., a Boise, ID-based developer of intelligent sensors to monitor the temperature of perishable foods. “They are becoming more and more discriminating at point of sale, seeking out the best and freshest products from retailers that they trust can deliver that higher-grade product,” he said. For the food industry, Oster added that efficiency and higher margins are a constant pressure, so “eliminating the current waste and spoilage (shrink) of product in-route will be a definite enhancement to the bottom line of those companies participating in a temperature-monitoring program.” When it comes to RTE items, a consumer might want to consider whether the food has been kept at the correct temperature before hitting the deli counter, whether it’s displayed properly, and what might be in store for that item after they buy it. “You have to think about how many times those things might be out of the temperature danger zone before they’re offered for sale,” noted David Walpuck, a certified professional in food safety (CP-FS) from The National Environmental Health Association and an administrator for The National Registry of Food Safety Professionals. “There’s the example of cooked meatballs kept at 41 degrees, which is the required cold holding temperature in New York state,” he said. “If they don’t eat it all, what’s going to happen to it? If there’s any flaw in the heating or cooling process, that’s going to be where it is.” Another consideration for the food industry is being able to track the conditions to which a product was exposed in case there’s a quality problem somewhere along the line, or, in any company’s worst nightmare, a foodborne illness outbreak is linked to that particular item. “We consider all areas of ‘cold chain’ important. When there is a break in the chain, you lose traceability and the capacity to perform root cause analysis,” said Brian Edwards, director of national chain store sales for DeltaTrak Inc. in Pleasanton, CA, which makes and sells temperature monitoring products. “If there is a break in the chain, and temperature-sensitive products go to waste, or worse — if there is a major recall, the impact spreads throughout the company and its bottom line,” he added. Edwards said that a large grower/shipper of cherries in the Pacific Northwest once told him that a lost load of cherries had cost more than $100,000. “That is my budget, keep my monitoring within 100k and it becomes an immediate ROI (return on investment),” he said. Besides the potential of losing a load of produce and a lot of money, specific problems accompanying a loss of temperature control include tarnishing any established reputation for providing a quality food product on time and possibly damaging a brand over the long term.
Temperature control and monitoring are also critical in the home kitchen, said Sally McNeill, an Extension educator at North Carolina State University. She pointed out that “TCS” foods (those needing time and temperature control for safety and which used to be called “potentially hazardous foods”) need particular care in order to lessen the chance of someone getting sick.
“One of the top reasons for foodborne illnesses is not cooking TCS foods to their minimum endpoint cooking temperatures. Another reason is the improper holding of hot and cold TCS foods,” McNeill told Food Safety News.
TCS foods include meats (beef, pork, lamb), poultry, fish, shellfish and crustaceans, sprouts and sprout seeds, milk and dairy products, heat-treated plant foods (cooked vegetables and legumes) and cooked rice, cut melons, cut tomatoes and cut leafy greens, baked potatoes, untreated garlic-and-oil mixtures (mixtures without an acidifying agent), and tofu or other soy protein.
While home cooks typically rely on visual cues to tell whether some TCS foods are safely cooked, the only sure way to know is by using a calibrated food thermometer, she said.
“As far as holding temperatures, hot TCS foods should be held at 135 degrees F or higher, and cold TCS foods should be held at 41 degrees F or less. Doing this can greatly reduce the risk of foodborne pathogens from multiplying to unsafe levels,” McNeill said.
In response to ever-increasing threats to food safety, scientific ingenuity has developed approaches that use sophisticated technology to monitor, track and record temperatures while food is in storage or in transit, and even while it’s on display. These systems use specially designed software to monitor and gather data via sensors or smart labels using handheld devices and then store the information on a company server and/or the cloud (an Internet-based network) for later tracking or auditing purposes.
“Just turn the label on, place it on the cargo, and it will be read automatically upon its arrival at the destination – all without human intervention,” Oster said. “If there is a temperature concern, the QA director, or other appointed person, will receive an alert on their smart phone that will completely explain the alert issue at hand, allowing the decision-maker to act on the spot with real-time data.”
Walpuck said his company uses disposable thermometers in product pallets, which can then be tracked via global positioning system (GPS) technology. He related that a truck was recently delivering dairy products to a supermarket, and the tracking person reported that it was coming in at 54 degrees F.
“They had to take the internal temperatures of the truck and, as it turned out, only one zone had the problem and it wasn’t the zone the dairy was in, so nobody got in trouble,” Walpuck said.
To decide what type of temperature tracking and monitoring approach makes sense from a cost perspective, details of a firm’s operational requirements are considered, Edwards said.
“It also depends on how long of a trip, or how long the logger will need to monitor temperatures. What type of transportation: ship, rail, airplane, etc.?,” he explained. There are other financial aspects as well, such as software investment and the type of reporting needed.
The days of having someone check a pallet or box of perishable food (or a deli case) and then make a phone call or send an email about a problem haven’t gone away, but it’s clear that the high-tech approach is playing an increasing role in maintaining food safety.
Whether paper temperature logs are used, or a high-tech cloud-based system, the challenge for the food industry is to make sure that employees know how to use the equipment and do so regularly and accurately.
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