The fridge is the focal point of a kitchen, but since it’s virtually always stocked with food, it can be tricky to remember that it needs to be cleaned too. In fact, because your fridge holds everything from leftover Japanese food to the raw chicken you plan to roast for dinner, it should be cleaned thoroughly–and perhaps more often than you think. To get the intel on when (and how often) to clean out this appliance and wipe down the inside—shelves, deli drawer, crisper, and more—we spoke to Tamika D. Sims, PhD, the senior director of food technology communications at the International Food Information Council.

When Should You Clean Out Your Refrigerator?

In addition to cleaning up any spills as they happen to prevent the spread of bacteria, you should give your fridge a deep clean about four times a year—it’s a good chore to do when the seasons change. Keep reading for more specific tips on when and how to clean your fridge. Aside from infant formula products, which are regulated by the federal government, these dates are not an indication of safety. “A ‘best if used by’ date indicates when a product will be of best flavor or quality. A ‘sell by’ date tells the store how long to display the product for sale for inventory management A ‘use by’ date is the last date recommended for the use of the product while at peak quality, and a ‘freeze by’ date indicates when a product should be frozen to maintain peak quality.” Foods in your fridge that have passed any of these dates may still be fine to eat, but check if they are still fresh. Any food that has molded, changed color, or is emitting a foul odor should promptly be thrown away. After disposing of spoiled food, wipe down the areas where the food was with hot, soapy water to prevent the spread of bacteria. Improperly stored food can lead to spills or leaks, and the affected areas of your refrigerator will need to be cleaned. Take special care storing raw meat or poultry products, as any leaks associated with those foods can cause harmful bacteria to spread to other items in your refrigerator. If you notice that raw chicken or steak, for example, has leaked in your fridge, thoroughly clean the affected area with warm, soapy water. Remove the shelf or drawer to complete the cleaning process.