Backyard egg storage is one of those topics where the official US guidance and the rest-of-the-world standard diverge so widely that new keepers get confused. The American grocery system washes eggs commercially, which means they must be refrigerated from packing to consumption. The European, Japanese, and most-of-the-rest-of-the-world standard sells eggs unwashed at room temperature and they are perfectly fine. The difference is the bloom, and understanding it is the key to backyard egg storage. This guide walks through what the bloom is, how it changes the storage rules, how long different storage methods actually preserve eggs, and the float test that tells you whether an egg is still good without cracking it.
The bloom
The bloom (also called cuticle) is a thin protein-and-glycoprotein layer the hen deposits onto the eggshell as the egg passes through her cloaca during the final minutes before laying. The bloom does several things at once:
- Seals the shell pores. An eggshell has 7,000 to 17,000 microscopic pores. The bloom plugs them.
- Blocks bacteria. Without the bloom, salmonella and other surface bacteria can enter through the pores.
- Reduces moisture loss. Sealed eggs lose moisture much more slowly.
- Protects the developing chick. The bloom evolved primarily to protect a fertilized egg through 21 days of incubation.
The bloom is water-soluble. Wash an egg in water, even briefly, and the bloom is gone permanently.
Why US eggs are refrigerated and European eggs are not
In 1971 the US Department of Agriculture mandated washing of commercial eggs at packing facilities to reduce salmonella risk. The wash removes the bloom, so refrigeration became mandatory through the entire supply chain.
In the EU, commercial egg washing is explicitly banned for the same reason. The bloom is preserved, eggs go to grocery shelves at room temperature, and salmonella risk is managed instead through flock vaccination requirements.
Both systems work. The US system requires refrigeration. The EU system requires the bloom. For backyard keepers, this is good news: you have the choice.
Room temperature storage of unwashed eggs
An unwashed egg with intact bloom keeps at room temperature (60 to 70 degrees Fahrenheit) for 2 to 4 weeks, with quality declining gradually rather than dropping off a cliff.
Quality timeline at room temperature:
- Week 1: prime quality, tight white, dome-shaped yolk.
- Week 2: still excellent, white begins to thin slightly.
- Week 3: white is thinner, yolk flatter, still fine for cooking.
- Week 4: noticeably aged but safe and edible. Best for baking or hard-cooking.
- Week 5+: float test required before use.
Storage conditions:
- Cool spot, ideally 50 to 65 degrees.
- Dry environment (high humidity accelerates bacterial growth if the bloom has any micro-cracks).
- Out of direct sunlight.
- Pointed end down (yolk stays centered, air cell stays at the top).
Refrigerated storage
Refrigeration dramatically extends storage regardless of whether the egg is washed or not.
Storage timeline at 35 to 40 degrees Fahrenheit:
- Unwashed eggs: 3 to 5 months at peak quality, 6+ months still safe.
- Washed eggs: 4 to 6 weeks at peak quality, 2 months still safe.
Storage notes:
- Keep eggs in a closed container or the original carton. Eggs absorb refrigerator odors quickly.
- Store on a middle shelf, not the door. Door storage cycles through temperature swings that age eggs faster.
- Bring eggs to room temperature 30 minutes before baking. Cold eggs in batter cause curdling.
When to wash and when not to wash
The default rule: do not wash unless necessary. Washing strips the bloom permanently.
Don’t wash if:
- Egg is visibly clean.
- Egg has minor dust or feather bits (dry-brush instead).
- You plan to store at room temperature.
Wash if:
- Egg is heavily soiled with feces or yolk from a broken nestmate.
- You plan to refrigerate immediately.
How to wash:
- Use water warmer than the egg (around 90 degrees Fahrenheit). Cold water creates negative pressure inside the shell and draws bacteria in through the pores.
- Wash quickly, do not soak.
- Dry with a clean cloth.
- Refrigerate within an hour of washing.
Dry cleaning soiled eggs
Lightly soiled eggs can be cleaned without water and without losing the bloom.
Methods:
- 220-grit sandpaper, very lightly buffed across the dirt.
- A dry rough cloth or paper towel.
- A fine-bristled nail brush, dry.
This preserves the bloom and allows continued room-temperature storage. Use water-washing only when dry methods are inadequate.
The float test
The float test is the most reliable home method for checking egg freshness without cracking.
Method: Submerge egg in a bowl of water deep enough to cover it.
Results:
- Lies flat on bottom: very fresh, less than a week old.
- Stands at a slight angle on bottom: about a week to two weeks old.
- Stands vertically on bottom (small end up or down): 2 to 3 weeks old, fine for cooking.
- Floats fully to surface: discard. The air cell has expanded past safe limits.
The science: an egg loses mass through the shell pores over time, and the air cell at the wide end of the shell expands to compensate. Once the air cell is large enough, the egg floats.
A floating egg may or may not be actually spoiled, but the indicator is reliable enough to use as a discard threshold without cracking. Cracking a possibly-bad egg into a bowl of good eggs can ruin a batch of pancake batter, so the float test is worth doing on any egg you are unsure about.
Water-glassing for long-term preservation
Water-glassing is a traditional preservation method that keeps unwashed eggs at room temperature for 12 to 18 months. The method uses a calcium hydroxide solution (pickling lime, food-grade).
Method:
- Dissolve 1 ounce of pickling lime per quart of cool water.
- Place fresh unwashed eggs in a glass or food-grade plastic container, pointed end down.
- Pour the lime solution over the eggs until fully submerged with at least 2 inches of solution on top.
- Cover loosely and store in a cool dark place.
Storage timeline: 12 to 18 months. Some sources extend to 24 months.
Use notes:
- Water-glassed eggs work for any cooked application: scrambled, fried, baked, boiled.
- Do not use for raw applications (mayonnaise, raw cookie dough).
- The whites are slightly thinner than fresh, so they do not whip to stiff peaks well. Use fresh eggs for meringues and angel food cake.
- Rinse before cracking to remove the lime film.
Freezing eggs
Eggs can be frozen for long-term storage, with one rule: crack them first.
Whole eggs: Beat together, freeze in ice cube trays or freezer bags. One large egg equals roughly 3 tablespoons of beaten mix.
Whites only: Freeze straight in ice cube trays. Whites freeze and thaw perfectly.
Yolks only: Add a pinch of salt or sugar before freezing to prevent gel formation. Label which (salt for savory, sugar for baking).
Storage: 12 months at 0 degrees Fahrenheit or colder.
See our methodology for the framework we use on poultry guides.
Frequently asked questions
Do backyard eggs really not need refrigeration?+
Unwashed eggs with the bloom intact keep at room temperature for 2 to 4 weeks. The bloom is a thin protein-and-glycoprotein coating the hen deposits as the egg passes through the cloaca. It seals the shell pores against bacteria and moisture loss. Washed eggs (including all US grocery-store eggs) lose this seal and must be refrigerated.
How can I tell if a backyard egg has gone bad?+
The float test is reliable. Place the egg in a bowl of water. Fresh: lies flat on the bottom. Week-old: stands at a slight angle on the bottom. Two to three weeks old: stands vertically on the small end. Bad: floats. Floating eggs have lost enough mass through the shell that the air cell has expanded past safe limits. Discard floating eggs without cracking them, the smell is unmistakable.
Should I wash my eggs before storing them?+
Only if dirty, and then refrigerate immediately. Washing strips the bloom, which means the egg must enter the refrigerated supply chain and stay there. Lightly dirty eggs can be dry-brushed clean (sandpaper or a dry cloth) to preserve the bloom. Heavily soiled eggs should be washed in water warmer than the egg (around 90 degrees Fahrenheit) and refrigerated.
What is water-glassing eggs?+
A traditional preservation method using a calcium hydroxide (pickling lime) and water solution. Unwashed fresh eggs submerged in this solution can store for 12 to 18 months at room temperature. The lime forms a hard outer coating that seals the shell completely. Water-glassed eggs work for baking and most cooking but not for raw applications like mayonnaise.
Why do my fridge-stored eggs sometimes have a sulfur smell?+
Eggs absorb refrigerator odors through their shells, and the older an egg gets the more it loses internal moisture and concentrates flavor compounds. A fresh egg in a clean fridge has no smell. A 6-week-old egg in a fridge that has held salmon or onions takes on those flavors. Store eggs in a closed container or the original carton, away from strong-smelling foods.
