Those of us in the food industry have all seen the ill-fated clipboard tracking temperature outside of the walk-in cold food storage unit. Historically, monitoring food temperatures in refrigerators has been conducted manually, adhering to a schedule and tracking the temperature at intervals on a piece of paper. But what happens when the employee tasked with monitoring the hourly temperature gets delayed? What if they just plain forget?
You Might Also Like
Explore this issueOctober/November 2018
I’ve seen employees who have forgotten to track the temperature throughout the day and fill in the end-of-day temperature for the entire day. They’re running the risk that if there was a spike in temperature outside of safe ranges during the day, the entire contents of the cold storage unit could be ruined, but they wouldn’t know it because they didn’t check the temperature. Not only is it wasting food and money, but it’s also putting consumers, real people, at risk.
Food handlers have the responsibility to ensure that consumers receive safe food products. That assurance starts with monitoring temperatures during the cold chain. Monitoring food storage can be especially tricky with human error. To adhere to federal regulations, companies must implement a quality management system to measure, control, and document temperatures. The best way to accomplish these three responsibilities is with a data logger. Data loggers report temperature data at set intervals to help monitor safe refrigerator or freezer conditions.
Traditional data loggers offer a step up from the unpredictable, human-based monitoring approach. Loggers ensure accurate data throughout the day and, with a USB connection, data can be downloaded manually to a computer. However, downloading the data manually presents problems. Users either have to remove the logger from the cold environment or take the computer into the cold storage area to download the data. Neither of these are productive. Taking the logger out can disrupt its recording and standing in a freezer downloading data is, well, cold.
The Issues with Data Shuttles
For this situation, data shuttles can be advantageous. Data shuttles are small handheld devices that attach to the logger to collect its data. Shuttles are easy to carry around and collect data from multiple loggers without having to remove the logger from its environment or taking a computer into the walk-in. The issues with data shuttles are physically collecting data at the end of the day and the shuttle’s memory filling up.
If users download the shuttle’s gathered information at day’s end, they will find out after the fact if the temperature went out of the safe range. The only recourse is to discard the storage contents. Users don’t want to find out hours later that everything has thawed and is now ruined. Depending on the size of the cold storage, whether it’s a small walk-in or a warehouse, and the contents of the refrigerator, throwing out tarnished goods can be an expensive mistake.
Similarly, depending on the necessary interval rate, data can fill up in the shuttle before someone can download the information to a computer. This can cause readings to be lost, so users won’t be able to access the temperature history or be aware if something detrimental occurred. Users won’t be able to prove to regulators the temperature history. An employee would have to routinely check the shuttle. But as with the clipboard, an employee is being relied upon to remember to check the data shuttle.
Automated Data Collection
Automated, network-connected data loggers can solve both problems. They eliminate the human element and data loss with real-time monitoring, internet connections, and alerting. Another plus is the cost-effectiveness. Technology improvements have driven the cost of connected data loggers down to the point where their cost is trivial compared to the complications that could arise by not monitoring in real time.
Automated loggers work with the user’s schedule and can eliminate many risks. The user specifies intervals and there is no need to remember to physically walk around to the data loggers before they fill up. A network connected data logger is extremely reliable because it will notify the user through a network or cellular connection if temperatures go out of a pre-selected range. Depending on the network infrastructure and needs, loggers can connect to a wired LAN connection or with Wi-Fi to connect to the cloud.
If using automated data loggers with a wireless connection, users will need a radio connection to a router, data collector, or access point of some kind. This can be problematic with thick metal side walls, where the transmission range is dramatically limited, but there are ways to get around it.
One solution is to place the logger with its integrated antenna outside the freezer and run the sensors through the door gasket. Thin 2-millimeter diameter thermistor sensors are needed. However, if the sensor is not placed inside the walk-in by any significant margin, the sensor can be subject to thermal transitions when the doors open. Some loggers or software ignore those temperature transients caused by doors opening. Typically, this is a setting, but be sure to have that setting available; otherwise there will be false readings.
With large walk-in refrigerators, people may want to monitor a spot far away from the door or multiple points inside. To solve the former, thermocouple sensors with a long wire to feed the sensor inside can measure the temperature at distances far from the logger itself. Measuring temperatures at multiple locations can be accomplished with a two-channel logger and long thermocouples or wireless loggers that connect using a 900 MHz signal instead of the average 2.4 GHz Wi-Fi signal. Those can be set up in multiple locations to then transmit to a repeater mounted on the outside wall of the walk-in. The repeater would then relay the signal to the access point, data collector, or base unit. The repeater solves the issue of the interrupted signals due to the metal walls of the walk-in.
Those storing food in cold chain must also be fully aware of the Food Safety and Modernization Act (FSMA). When food is frozen, microbes go into a dormant stage, but when the food begins to thaw, microbes become active again and start multiplying to levels that can lead to foodborne illness. FSMA states that it is the federal government’s right to inspect any food handling location at any time, so safe temperature data need to be proven. Data loggers facilitate thorough inspection and can allow for quicker compliance.
One way to track all temperature data over time to share with regulators is with WebStorage Service, T&D Corp.’s free cloud storage service. WebStorage Service stores temperature data collected by T&D data loggers. Data are retrievable and charted and can be viewed later. Food handlers can prove their temperature data and show regulators their safe practices.
FSMA also requires food handlers to develop a plan that meets the guidelines for Hazard Analysis and Critical Control Points (HACCP), which should involve an automated data logger. Issues with data entry, misreading, and misinformation are the responsibility of the food handler, and failure to comply with these guidelines can result in seizure, injunction, and recalls, all of which can damage the reputation of the entire supply chain.
To adhere to HACCP, food handlers must establish critical limits for each CCP. This includes monitoring activities to ensure that the process is under control at each point in the food manufacturing process. Data loggers are essential to this adherence. Automated data loggers alert users via email, text, or push notification when temperature measurements go out of the set range. Users can know the exact moment temperature goes out of safe levels and the problem can be fixed in real time, negating the risk of ruining supplies.
A Refrigeration Mishap Example
The need for flexible, automated data loggers to monitor and alert can be understood through Southern Wine & Spirits’ refrigeration mishap. The winery hosts events for its visitors where they can test different beverage and food pairings. That means that the company needs to store food, such as cheese, vegetables, fruit, and seafood.
Last year, the kitchen had a few equipment failures with its refrigerators and freezers. Food safety regulations state that once products go above the 40 degrees Fahrenheit safe zone, staff have only about four hours to get it back to temperature before the food has to be discarded. These equipment issues inconvenienced the kitchen, as staff had to move food between fridges several times to keep everything fresh.
The chef and his assistants had previously tracked temperatures using thermometers integrated into their storage units. But when the team would be busy preparing food for long stretches of time or left for the night or weekend, they couldn’t check the temperatures as often as needed.
To keep this from happening again, Southern ordered wireless temperature data loggers to monitor each storage unit. Wired systems weren’t practical given the kitchen layout. Southern attached the loggers to the front of the units using Velcro tabs, and the data loggers’ external sensors were secured inside the refrigerator. An Ethernet network base station was also installed to collect the logger readings automatically.
Now the data loggers automatically take temperature readings once an hour and check for alarm conditions every five minutes. This way, Southern chefs can work knowing that an alarm will trigger whenever temperatures go outside safe limits, indicating that a fridge is failing and starting to warm up. The company also has the ability to report safe temperature data if ever necessary.
Using advanced data loggers in the food industry can prevent contamination issues. It’s time to upgrade the clipboard. Network connected loggers can negate many food safety monitoring issues through temperature control, offsite monitoring, and notifications.
Knuth is the president of TandD U.S. Reach him at email@example.com.