Why eggs sit unrefrigerated in supermarkets but should be chilled at home, especially in summer

You go to the supermarket, grab a dozen eggs from a shelf at room temperature, and when you get home, you put them in the fridge. It seems counterintuitive, but it isn’t: the key isn’t to always choose cold or always room temperature, but to avoid sudden changes.

Until they’re sold, eggs must be kept clean, dry, protected from impact, away from strong odors and direct sunlight, at an appropriate and preferably constant temperature. That’s why many supermarkets don’t store them in refrigerated display cases: if a cold egg is then moved to a warm, humid environment, condensation can form on the shell. This “sweat” causes the surface to become damp, which is undesirable for a porous food covered by a protective cuticle.

Once at home, the situation changes. The eggs will no longer be subjected to transportation, shelf time, bagging, or handling. The best course of action is to choose a stable place and keep them there until they are consumed. In most households, especially in the summer, that place is inside the refrigerator.

Storing eggs in the refrigerator helps slow down their aging process. Over time, eggs lose water and carbon dioxide through the shell; the air cell expands, the egg white becomes more liquid, and their culinary quality declines. Cold temperatures don’t turn an old egg into a fresh one, but they do help preserve its properties better.

It also enhances safety. Salmonella isn’t present in all eggs, but the risk associated with raw or undercooked eggs isn’t zero. That’s why it’s best to combine responsible purchasing, refrigeration, hygiene, and thorough cooking whenever the recipe allows.

The egg tray on the refrigerator door seems convenient, but it’s usually not the best place. The door is the area where the temperature fluctuates the most: it opens, closes, and is exposed to warm air from the kitchen. Plus, those compartments aren’t always as clean as they should be.

The best option is to store them in their original carton on an interior shelf. The carton protects them from bumps, reduces odor absorption (the shell is porous), and keeps important information—such as the best-by date or lot number—close at hand. If you want to be extra careful, place them with the pointed end down to keep the air chamber at the top.

Another helpful tip: take out only the eggs you’re going to use and don’t leave the whole carton on the counter while you’re cooking.

It’s not a good idea to wash eggs before storing them. Although it may seem more hygienic, it can actually be counterproductive: water can wash dirt or microorganisms into the pores of the shell and damage the protective cuticle.

If an egg is very dirty, it’s best not to use it for delicate dishes. If it has a small spot, you can wipe it off with a dry cloth. If you do wash it, do so right before using it, not before storing it. After handling raw eggs or eggshells, wash your hands and clean any utensils that have come into contact with them.

It’s also best to crack the egg onto a flat surface rather than on the edge of the bowl where you’ll be beating it, to minimize shell fragments falling into the mixture.

In the summer, keeping food cool once you get home becomes even more important. Kitchens get hotter, the trip home from the store can be long, and some egg-based recipes—such as runny omelets, homemade mayonnaise, Russian salad, or creamy desserts—are sensitive to being left out of the fridge for too long.

The rule of thumb is simple: buy eggs with intact shells, follow the best-by date, bring them home quickly, and store them in the refrigerator. For pregnant women, young children, the elderly, or immunocompromised individuals, avoid dishes made with raw or undercooked eggs. In these cases, pasteurized eggs are a safer alternative.

If you have leftover egg-based dishes, refrigerate them as soon as possible in a clean, covered container.

To follow these recommendations without giving up simple recipes, prioritize dishes in which the egg is cooked thoroughly and eaten at room temperature without having to wait too long.

Eggs aren’t kept at room temperature in the supermarket to prevent condensation and temperature fluctuations before purchase; at home, however, it’s best to store them in the refrigerator because it offers a more stable temperature than the kitchen, especially in the summer.

Don’t store them in the door, don’t wash them before storing them, and keep them in their original packaging. This isn’t about causing alarm, but about understanding how this porous and delicate food item works. With a few simple steps, eggs will keep better, maintain higher quality, and reduce unnecessary risks.