Cooked too much and want to store some of your food in the fridge for later consumption, but aren't sure whether you should cool it first? The Conversation examines the science of food storage (and food poisoning) and offers up a simple suggestion: if in any doubt, freeze it as soon as the steam stops rising. If you leave food to cool for too long, the risk of bacterial nasties increases rapidly.
Picture by rfduck
University of Newcastle nutrition professor Clare Collins explains the process:
As cooked food drops to 60°C or below, bacteria that have survived the cooking will start to multiply until the food cools down to five degrees. The longer the food is left to cool, the longer the bacteria – which causes food poisoning – has to multiply.
If you're super-paranoid, you can use a food thermometer to measure the internal temperature. But in the real world, that's a somewhat unlikely scenario, and this advice seems more useful:
If you intend to store cooked foods to eat later, you can cool it on a bench as long as the temperature doesn’t drop below 60°C. This is roughly when the steam stops rising. You can keep cooked meals safely in the fridge for a few days, but if you want to keep it for longer, put it straight into the freezer.
Time of cooling aside, it's often tempting to pop leftovers in the fridge, because that way they'll be easier to reheat (and you can potentially eat them cold). But if you want to reduce the risk of food poisoning, let your food cool just to non-steaming point, and then freeze. If you've got a microwave, getting your food back to a heated state won't be any trouble. Another useful pointer from the article: always defrost in the fridge. Defrosting on the bench also increases the risk of bacteria multiplying as the food sees its temperature rise.
Monday’s medical myth: leave leftovers to cool before refrigerating [The Conversation]