This Food Safety article originally appeared in full on Health Inspector’s Notebook, a website by Jim Chan, a retired Toronto Public Health Inspector. Jim has generously agreed to share his knowledge and expertise with us here on the FoodReach site.
Why temperature control is important in food safety?
Disease-causing microorganisms such as bacteria grow very slowly at low temperatures (4 °C/40°F or lower), multiply rapidly in mid-range temperatures ( 5 °C/41ºF to 60 °C/140ºF), and are killed at high temperatures (60 °C/140ºF or higher).
For safety, always keep ‘cold food cold‘ and ‘hot food hot‘. Perishable or hazardous foods must be held at cold or hot temperatures to inhibit bacterial growth and food must be cooked to temperatures high enough to kill harmful microorganisms before eating.
What is the Danger Zone?
Food safety while cooking?
There are different types of food thermometers in retail stores, but the best is to use a metal stem or digital thermometer to check the internal temperatures to ensure the food is properly cooked all the way inside.
- Clean and sanitize the probe thermometer first
- To get a more accurate temperature, insert the probe thermometer in several parts of the meat. Always insert in the thickest part of the meat and the probe should not touch bone inside.
- Check the internal temperature for at least 15 seconds to get a true temperature.
- Always clean and sanitize the probe thermometer after use and before checking a different food item to avoid cross-contamination.
What internal temperatures should food be cooked to?
Different foods have to reach different temperatures in order to be safe. More specific information on cooking temperatures for different types of food items can be found on the Health Agency of Canada website.
Other safe cooking tips:
- Never cook large roasts, whole chicken or turkeys while they are still frozen. The large size keeps the insides from cooking to a safe temperature, food looks cooked on the outside but still raw inside and can post a risk for food poisoning.
- Meat must be thawed completely first so the heat can reach the center of the meat faster during cooking.
- Microwave oven is good for re-heating food but does not cook food evenly, especially cooking raw meats. If using a microwave oven cooking food, avoid cooking large cut meat or whole poultry and food must stir and turn while it cooks to make sure it cooks to the same temperature in every part.
- Check the food with a metal stem or digital thermometer before serving.
- Never keep metal thermometer in the food while it is cooking in the microwave oven, only use specific thermometer designed for use in microwave oven.
Frozen processed food
- Some breaded processed food items such as fish sticks, chicken burger patties or nuggets are raw and ‘look cooked’, they can even look like ready-to-eat food in the photo on the packages. Check the information to see if it indicates ‘uncooked‘ or ‘raw‘. There are many misleading labels such as ‘cooking is needed’, ‘Don’t eat directly from package’, ‘May require cooking’ etc.
- Do not just follow the instructions such as ‘Preheat oven to 200 ºC /400 ºF and bake for 24-26 minutes‘, unless there is a thermometer in the oven to check and show the accurate oven temperature, do not just turn the dial to 200 °C/400 ºF as the degrees can be off between the dial and the oven’s temperature.
- Always treat ‘uncooked’ or ‘raw’ processed food as fresh raw meat, poultry or seafood and use the specific cooking temperatures as indicated in the Cooking and Re-heating Temperatures for Hazardous Food chart.
- Be sure to use a metal stem or digital probe thermometer to ensure the internal temperature is cooked to a safe temperature.
- Do not trust gadgets such as a pop-up indicator that came with a turkey as this indicator does not usually give an accurate safe internal temperature. Sometimes it pops too early and ends up with under cooked turkey, which can post a risk of Salmonella food poisoning, or if it does not pop, the turkey may end up being over cooked. Also, it is usually inserted in the breast area less than 5 cm or 2 inches deep and hardly deep enough to give a safe internal temperature of the whole turkey.
- The best and the safest way to ensure the food is fully cooked to the proper internal temperature is by using a metal stem or digital thermometer to check the internal temperature.
Jim Chan began his career as a Public Health Inspector at Toronto Public Health in 1977 after completing his science degree at University of Guelph and the Environmental Health program at Ryerson University. Throughout his 36-year career, Jim has been responsible for managing and implementing programs and activities dedicated to the protection of public health. Programs such as Food Safety Inspection (DineSafe Toronto), Communicable Disease Control (including case management during the SARS outbreak in 2003 and health & safety during the H1N1 outbreak in 2009), Infection Control, Tobacco Control Enforcement and Health Hazard Investigation.
Jim retired on October 31, 2013 from Toronto Public Health. After retirement, Jim began an interesting career as a food safety consultant to media outlets & on-air guest in various TV shows, presenting at conferences and workshops, developing food safety training materials, and promoting public health and food safety using social media. Jim’s recent adventure is teaching a food safety course to public health inspectors at Conestoga College, School of Health & Life Sciences in Kitchener, Ontario, Canada.
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