We live in a time where increasing the shelf life of food is easy. At home, we all take the ability to chill or freeze our food in a bid to lengthen its viability for granted. Yet, do we really know the dos and don’t of refrigerating our food safely?
One common question is WHEN do we put the food into the refrigerator? Do we let it cool down naturally at room temperature before placing it in the fridge? Or do we put it in the refrigerator straightaway?
Pathogenic bacteria grow quickly in food at temperatures between 40 to 140 degrees Fahrenheit or 5 to 60 degrees celsius. In order to kill these bacteria, food should be cooked thoroughly (bacteria is killed at 100 degrees celsius) and after the food is cooked, it should not be left at this danger zone temperature range to avoid bacterial growth. With this in mind, you may want to reduce this risk by immediately placing your hot leftovers into the fridge. This is especially the case with small amounts of food.

Our modern fridges are extremely efficient and small amounts of food will be quickly brought down to cooler temperatures (below 5 degrees celsius). By small amounts, I mean single servings of foods that can be placed in small glassware containers.
Larger amounts of food might be trickier given that it will take your fridge a long time to cool these down to a safe temperature. At the same time, leaving them to cool down naturally may place them in the temperature danger zone and increasing your risk of foodborne illness.
Perhaps the best way to deal with larger amounts of food would be to separate out into small portions, placed into different airtight glassware shallow containers and refrigerated separately.
Another common question is how quickly cooked food should be refrigerated.
According to the U.S. Department of Agriculture (USDA) hot leftovers should be refrigerated within 2 hours after cooking or removal from a cooking device — and 1 hour if the temperature is above 90°F (32°C).

There is also the question of how long you can refrigerate food before it goes bad. As a general rule of thumb, leftover foods may be refrigerated for 3–4 days or frozen for 3–4 months.
What are the other tips for safe food storage?
Here are other ways you can ensure that your leftovers will be safe to eat?
1.Wrap well. Store leftovers in airtight containers or cover them to avoid bacterial growth and keep odours from other foods out.
2. Use the top shelf of the fridge. Store your leftovers on the upper shelves of the fridge, making sure to eat the dishes you refrigerated earliest to avoid food spoilage. Keep older leftovers at the front and fresher ones toward the back.