Sous Vide Cooking Using a Temperature Data Logger

CAS DataLoggers Helps a Chef Ensure That Food Temperatures Are Just Right

CAS DataLoggers has just supplied the temperature monitoring solution for a large caterer specializing in cooking sous vide food (French for ‘under vacuum’). This increasingly popular style uses thick vacuum-sealed pouches to slow-cook food at below boiling temperatures anywhere from half a day up to 3 days. Using sous vide, the business produces extra-tender meat including short ribs, chicken, and salmon as well as vegetables that keep their crisp taste. First the food is sealed inside the pouches which are then placed in a water bath to gradually heat them at the target temperature. Within the bath they’re cooked evenly to lock the juices in. They can cook large joints of meat this way and lots of filets at once, so the business always has slow-cooked food ready to reheat and serve for an upcoming event.

Although it produces delicious food, sous vide is a very demanding all-day process requiring accurate equipment to continually monitor the food’s core temperature. Health and safety are also paramount since the technique uses such low temperatures. The food is cooked until pasteurized, but the time this takes varies with the food’s shape and size. For example, the chef cooks a few salmon dishes at 54°C (130°F), so he has to periodically check the temperature to ensure that the meat is cooked thoroughly and safe to eat. He had heard about people using data loggers for sous vide and gave us a call to get a price quote on a model.

CAS DataLoggers provided the caterer with a Grant Squirrel Portable Temperature Datalogger to monitor their sous vide process in real time. The data logger features 6 thermocouple inputs for use with a wide range of Type T and Type K thermocouple probes. CAS DataLoggers also supplied the kitchen with several Type T probes tipped with a needle point for easy insertion into the pouches. Staff cook these pouches inside a water bath which is set to the desired temperature. A pump keeps the heated water moving to cook the food more evenly, while a timer counts down. After removing the pouches, the chef then chills them in a refrigerator under vacuum so the meat can’t spoil.

After placing the food within the vacuum pouches, the chef fixes foam tape to the top of each bag and sticks the needle probe through the foam into the thickest part of the meat. This way, the pouches retain their vacuum pressure and the food cooks while the thermocouple probes log the core temperature of the meat. Using the Grant logger, it’s easy to monitor 2-3 pouches at a time during large orders and the wedding season.

The data logger is portable and lightweight so the chef can hold it in one hand while checking the food’s current temperature. Its standalone battery operation means it can be left on the countertop for days to log the temperature inside the pouches while kitchen staff prepare other dishes. The Grant logger records at fast sample rates up to 8 samples a second, more than enough speed to cover sous vide applications.

Staff can also set the logger to automatically start and stop logging at specific times and temperatures, which helps to manage the time-intensive process and get the most accurate view of internal meat temperature. Meanwhile the Grant logger’s large memory stores up to 250,000 readings of data, with each temperature reading showing the time and date.

Using the built-in display, it’s easy for staff to move through the data logger menus with the 3-button design. They can also navigate menus from a PC. By checking the display, the chef can see when temperatures get too high or low from his preset levels and adjust the water bath to get the food back to proper temperature. Kitchen staff also use the logger while heating and then grilling the meat, and then it’s ready to serve to a delighted crowd.

The data logger includes SquirrelView set-up and analysis software for PC, which makes it easy for the chef to view recorded data to fine-tune his sous vide process. The software’s user friendly, spreadsheet style interface allows quick setup of the data logger, quick downloads, and direct export to Excel. Flexible data presentation allows the chef to quickly display and analyze real time or historical data as a line graph, bar chart, etc.

The Grant data logger is easy to use and helps ensure that the caterer’s product is high-quality. The supplied thermocouples are inexpensive and simple for staff to place into the pouches, while the logger is also ideal for providing health and safety assurances to regulators that the meat was cooked properly and free of health risks. Along with the logger and temperature probes, CAS DataLoggers also provided their catering business with free technical support so they could get up and running with their application.