Leaving rice at room temperature for too long, storing large quantities, keeping it in the refrigerator for too long, not reheating it evenly and repeatedly are mistakes that should be avoided when storing cold rice.
Improperly stored rice can create conditions for bacteria to grow, increasing the risk of food poisoning. Some habits when cooling, storing and reheating rice should therefore be noted.
Leaving rice at room temperature for too long
Rice may contain spores of Bacillus cereus, a type of bacteria that can survive cooking. When cooked rice is not stored properly, especially at an inappropriate temperature for a long time, bacteria can grow and create toxins.
According to Medical News Today, the risk does not lie in whether the rice is reheated or eaten cold, but is mainly related to how the rice is handled and stored after cooking. Therefore, do not leave rice at room temperature for too long before putting it in the refrigerator.
According to the US Department of Agriculture (USDA), leftovers should be refrigerated within 2 hours of cooking. If the ambient temperature is above about 32 degrees Celsius, this time should be shortened to about one hour. You should avoid leaving the pot of rice on the table until evening or overnight before storing it in the refrigerator.
Stores large amounts of rice
Many people have the habit of leaving a large amount of rice in the pot, waiting for it to cool completely before storing it in the refrigerator. This method can cause the rice inside to remain at a temperature favorable for bacteria to grow for a long time. Medical News Today points out that with a large amount of rice, you should divide it into small portions, spread it in a shallow box to let the rice cool faster, then cover it tightly and store it in the refrigerator. This method helps limit the time the rice is in the temperature range that is favorable for bacteria to grow.
Stored in the refrigerator for too long
Putting rice in the refrigerator does not mean you can keep it for as long as you want. Safe storage time also depends on the cooling method, refrigerator temperature and condition of the food.
According to the USDA, many types of leftovers can be stored in the refrigerator for 3-4 days if refrigerated and stored properly. However, with rice, some food safety guidelines give a shorter time. For example, the UK Food Standards Agency (FSA) recommends that refrigerated rice should be used within 24 hours.
Therefore, with rice, priority should be given to using it in a short time and before eating, and should not rely solely on smell, color or viscosity to evaluate safety. Food can contain bacteria or toxins without obvious signs of spoilage. If you suspect the rice has been stored incorrectly, you should throw it away instead of trying to take advantage of it.
The rice is heated but not heated evenly
Reheating rice can kill many types of bacteria, but this should not be considered a step that can fix all problems caused by improper storage. According to the USDA, leftovers should be reheated to at least 74 degrees Celsius. With microwaved rice, care should be taken to distribute the heat evenly, because some parts may still be cold while other parts are already very hot.
You can divide the rice into small portions, add an appropriate amount of water and cover with a microwave-safe lid that can be opened or vented to allow steam to escape. During the heating process, you should stir or rotate the rice to spread the heat more evenly. After reheating, you should check multiple locations in the rice instead of just relying on whether it's hot outside. If you have a food thermometer, you can use it to check that the internal temperature is at least 74 degrees Celsius.
Reheat over and over again
Each time it is removed from the refrigerator and left at room temperature, rice can be exposed to conditions favorable for bacteria to grow if not handled properly. Therefore, you should divide rice into enough portions for each meal right from the time of storage, only taking out the portion you need to eat to reheat.
According to the UK Food Standards Agency (FSA), rice should not be reheated more than once and should be heated thoroughly before eating. If you have reheated a large amount of rice but cannot finish eating it, do not continue to store it for reheating next time. It's better to take just the amount of rice you need for each meal, keep the rest in the refrigerator and limit the amount of rice you put in and out multiple times.
Cold rice does not have to be refrigerated or reheated to make it unsafe. The risk largely depends on how the rice is cooled, stored and handled after cooking. Therefore, instead of worrying too much about eating reheated rice, you should pay attention to the steps after cooking: do not leave the rice at room temperature for too long, cool and store appropriately, use within a reasonable time, check for any abnormalities and reheat thoroughly before eating.
These measures are not guaranteed to eliminate all risks, but they can help reduce the likelihood of rice becoming a favorable environment for bacteria to grow.
