How to Tell if a Lemon is Bad? [6 Signs & Storage Tips]

Lemons are a versatile citrus fruit that can eventually spoil if not used in a timely manner. Knowing how to identify signs of bad lemons can help avoid accidentally consuming spoiled fruit. This article covers indicators of fresh versus rotten lemons, proper storage methods, causes of spoilage, if moldy lemons can be safely eaten, and how long lemons last at room temperature or refrigerated. Using these guidelines can help ensure you are able to fully enjoy lemons before they deteriorate.

Signs of a Fresh Lemon

Here are some signs that indicate a lemon is still fresh and good:

• Bright yellow color. No greenish, brownish, or black tints on the skin.
• Smooth, glossy skin. The rind appears shiny and firm with no wrinkling or soft spots.
• Firm flesh. It feels firm and heavy for its size, not lightweight or hollow-feeling.
• Plump shape. A fresh lemon has a round, plump silhouette with blunt ends.
• Characteristic aroma. It has a tart, tangy lemon scent when skin is scratched.
• Moist stem. The green stem end looks freshly cut, not dried out.
• Juicy inside. The pulp is juicy, succulent and bright in color with no dark streaks.

Shriveled, dried out or bruised lemons are past their prime and spoiling.

What Causes Lemons to Go Bad?

There are a few reasons why lemons eventually spoil:

• Moisture loss. Lemons lose moisture over time after harvest, causing shriveling and mold growth.
• Acidity reduction. Acidity decreases as lemons age, allowing mold and bacteria to grow.
• Physical damage. Bruising, puncturing, and tearing of the rind accelerates decay.
• Respiration. Lemons continue respiring after picking, using up nutrients and deteriorating.
• Temperature exposure. Heat exposure hastens moisture loss and microbial growth.
• Ethylene exposure. This naturally occurring ripening gas triggers lemons to over-ripen.

Proper post-harvest handling and storage slows deterioration processes to maintain freshness.

6 Signs That Your Lemon Is Bad

Like other fresh produce, lemons don’t last forever. There are visible signs that indicate when a lemon has gone bad and may not be usable.

How to Tell If a Lemon Is Bad? Check for these key indicators that a lemon has gone bad:

1. Mold Growth

Perhaps the most obvious sign of spoilage is mold growing on the rind or at the stem end of the lemon. You may see blue, green, black or white mold in spots or patches.

Never use a lemon with any mold on the peel or stem. Mold can spread beyond what’s visible and release harmful toxins. Promptly discard moldy lemons.

Key Point: Visible mold growing anywhere on the lemon is a clear sign it has spoiled.

2. Soft Spots

Fresh lemons feel uniformly firm when squeezed. As lemons deteriorate, soft spots or indented areas develop on the peel. The flesh beneath becomes mushy or crumbly rather than firm.

Soft spots indicate microbial activity and advanced internal spoilage. Toss lemons with any soft indentations or leaks.

Key Point: Soft, mushy spots on the peel or flesh mean the lemon has gone bad.

3. Wrinkled Skin

The rind of fresh lemons looks smooth and glossy. As lemons age, the peel becomes increasingly wrinkled, shriveled and dull looking. Deep wrinkles indicate excessive drying.

A withered, shrunken peel signals decreased internal quality and flavor. The wrinkled rind lacks the tautness of fresh lemons.

Key Point: A deeply wrinkled, shriveled lemon peel shows loss of moisture and freshness.

4. White Spots on Skin

Tiny white specks or patches on the lemon rind do not necessarily signal spoilage. These “spider mites” are harmless imperfections that occur during growth.

However, avoid lemons with excessive white mold-like growth. And cut away any spongy white areas on the peel before using.

Key Point: Small white specks are not harmful. But avoid lemons with heavy fuzzy white growth.

5. Greenish Discoloration

Good ripe lemons are uniformly yellow in color. As lemons over-ripen, green patches and tints develop on the skin. Green areas lack the tartness of ripe, yellow lemons.

While not unsafe to eat, greenish lemons have lower acidity and diminished flavor. Their juice provides less tang.

Key Point: Greenish rather than yellow color results from over-ripening on the tree. It negatively affects lemon flavor.

6. Dry, Hollow Center

A fresh lemon should feel heavy, indicating a moist and juicy center. Lemons with a lightweight, hollow interior have dried out from aging.

Gently squeezing the ends can reveal an overly dry center. The flesh will lack moisture and juice. Hollow lemons yield very little useable juice or zest.

Key Point: A dried out, lightweight lemon lacks the necessary juice and moisture. The hollowed internal flesh indicates overripe fruit.

How to Store Lemon?

Lemons need to be stored properly to maximize their shelf life and prevent spoilage.

Follow these guidelines to retain lemon freshness in the refrigerator or at room temperature.

How Long Do Lemons Last?

Properly stored, lemons generally last:

• Whole lemons at room temp – 2 to 4 weeks
• Whole lemons refrigerated – 1 to 2 months
• Cut lemons refrigerated – 3 to 5 days

Refrigeration prolongs the shelf life. But chill only what you plan to use short term, as cold damages texture and flavor.

Key Point: Lemons keep 3-4 weeks on the counter. Refrigerate cut lemons and use within 5 days.

Storing Whole Lemons

To store fresh uncut lemons:

• Leave at room temperature on the counter away from direct sunlight until ready to use.
• Place in a bowl or basket with good air circulation. Avoid sealing in plastic bags.
• Whole uncut lemons can be left out on the counter for up to 1 week before quality declines.
• For longer storage, refrigerate whole unwashed lemons in the high humidity crisper drawer for 2-3 weeks.

Leaving whole lemons at room temp is fine short term, but refrigeration prolongs freshness. Now let’s look at storing cut lemons.

Storing Cut Lemons

Once a lemon is cut open, it is more perishable. To store:

• Rub exposed cut surfaces with a little lemon juice to prevent browning.
• Wrap tightly in plastic wrap or store in an airtight container.
• Refrigerate cut lemons up to 5 days. Discard if mold develops.
• Freeze lemon slices or juice in ice cube trays for longer storage.

Properly contained, cut lemons can last a week in the fridge. Freezing extends the shelf life even longer.

Can You Freeze Whole Lemons?

Freezing whole uncut lemons is not recommended. Here’s why:

• Freezing causes damage to the peel and rind.
• Thawed lemons become mushy and mold faster.
• Texture changes affect juiciness and squeezability.
• Lemons lose fresh flavor when frozen whole.

For best results, only freeze lemon juice or slices rather than whole fruit. Refrigeration is still best for whole lemons.

Storing Lemon Juice

Fresh squeezed lemon juice should be:

• Placed in an airtight, non-reactive container like glass. Avoid metal.
• Refrigerated for up to 5 days.
• Frozen in ice cube trays or muffin tins up to 6 months.
• Labeled with date and use within recommended time.

Lemon juice can also be canned or preserved for longer storage. Refrigerating is best for short term storage.

Freeze Lemon Slices for Long Term Use

You can also freeze sliced lemons. Here’s how:

• Wash and dry lemons. Slice very thinly into rounds.
• Arrange in single layer on parchment paper lined baking sheet. Freeze until solid.
• Transfer frozen slices to an airtight freezer bag or container, storing flat.
• Remove as much air as possible and seal bag.
• Frozen lemon slices keep up to 6 months at 0°F.
• Add frozen slices to water, tea, baked goods or sauces without thawing.

Frozen lemon slices retain their bright citrus flavor for convenient use in recipes.

Can Eating a Spoiled Lemon Make You Sick?

It’s very unlikely. While moldy produce should always be avoided, lemons are acidic enough that harmful microbes have difficulty growing even when spoiled.

There is a very small risk of reaction in those with severe mold allergies. But most people can safely discard and compost rotten lemons without issue.

Similarly, while the flavor is diminished, overripe lemons with greenish hues or dry flesh pose no safety risks if the peel and inner flesh show no visible mold.

Key Point: Due to their acidity, moldy or overripe lemons are very low risk of causing illness if accidentally ingested by most healthy people.

Can You Use a Cut Lemon Gone Bad?

No, it is best to discard the entire lemon if any mold growth is spotted or if large soft spots develop on cut lemons in storage.

The mold can send “root threads” through the flesh that are invisible to the naked eye. Any sections that have become translucent or watery have also lost quality beyond recovery.

Likewise, do not use moldy lemon peels, juice or segments in drinks or cooking. The mycotoxins cannot be guaranteed to be destroyed by heat or freezing. It’s not worth the risk when citrus fruits are inexpensive and easy to replace.

Key Point: A lemon that is moldy or has large soft spots should be fully discarded once deterioration begins.

How to Revive an Old Dry Lemon

If you have a slightly dried out lemon, it can be revived with this method:

• Place the lemon in a bowl and cover with very hot, almost boiling water for 5 minutes. This rehydrates the rind and flesh.
• Remove lemon from water, pat dry, and let sit until back to room temperature before juicing or using.
• Use rehydrated lemon soon within a few days. Discard any lemons that seem overly dry or damaged.
• Avoid letting lemons get too dried out before reviving. Best results are obtained when caught early.

For mildly shriveled lemons, a hot water bath plumps them up for a little more use before full deterioration sets in.

How to Select Fresh Lemons

Picking ripe, recently harvested lemons gives you the longest window of use before they spoil. Look for:

• Firm, heavy lemons that feel full of juice. Light lemons tend to be dry.
• Lemons with thin, fine textured skin vs. coarse thick peel.
• Bright, uniform yellow color. Greenish tinges indicate under ripeness.
• Intact skin free of blemishes, bruises or wrinkling.
• Lemons that have a noticeable citrus fragrance when scratched.

Choosing great quality lemons ensures you get the most use and flavor before deterioration occurs.

Frequently Asked Questions

How can you tell if a lemon is bad inside?

Cutting open is the only way to check internal condition for mold, dark streaks, or other spoilage. Rely on outer signs like shriveling, soft spots and mold to determine freshness.

Is it okay to eat the lemon skin/rind?

Yes, the zest and peel are edible. However, the outermost layer is bitter and usually discarded. Wash thoroughly since pesticides concentrate on the skin. Avoid eating skins of moldy lemons.

Why do lemons get white stuff on the skin?

The white coating, called wax bloom, is from the natural wax on the lemon skin. It appears as lemons lose moisture during storage. It’s harmless but can be washed off before use.

Can spoiled lemons make you sick if the juice is cooked?

It’s unsafe to use lemons with substantial mold or decay. Mold toxins and bacteria can withstand cooking temperatures. Discard bad lemons fully rather than trying to salvage.

Do lemons continue ripening after picking?

No, lemons do not ripen further after harvest like some other fruits. Lemons should be left at room temperature until ready to use, but their sugar content does not increase.

Final Takeaways

Knowing how to identify signs of fresh versus spoiled lemons allows you to use them at their best. Look for mold-free, firm lemons without wrinkled skin or soft spots. Understand refrigeration extends shelf life once ripe. Allow unripe lemons to ripen at room temperature first. Frozen juice retains the bright citrus flavor when thawed. Discard moldy lemons fully. Following proper harvesting, handling and storage guidelines helps prevent spoilage and waste.