How to Remove Worms from Nuts Using Safe and Effective Methods

October 8, 2025 •

4 min read

It's a common pantry occurrence: tiny white larvae or 'worms' suddenly appear in stored nuts, often to the surprise of many. These larvae, typically from moths or weevils that lay their microscopic eggs on the nuts before or after packaging, can be safely dealt with once discovered. This guide will show you how to remove worms from nuts using simple, non-toxic techniques and prevent them from returning.

Quick Summary

This guide provides proven techniques for safely removing worm infestations from nuts. It covers methods like freezing and heating to kill larvae and eggs, proper cleaning protocols, and essential steps for secure long-term storage to prevent re-infestation.

Key Points

Isolate the infestation: Immediately seal and quarantine any suspected nuts to prevent pests from spreading to other pantry items.
Use cold or heat to kill pests: Freeze nuts at 0°F for at least four days or heat them in an oven at 140°F for 15-30 minutes to eradicate eggs and larvae.
Clean and discard contaminated nuts: After treatment, inspect nuts and discard any that are damaged, discolored, or show signs of webbing.
Sanitize your storage area: Thoroughly vacuum and wipe down pantry shelves and crevices with a vinegar solution to remove any hidden pests or eggs.
Store in airtight containers: Transfer all nuts to secure, airtight containers to prevent future infestations. Consider adding a bay leaf as a natural repellent.
Use the freezer for long-term storage: For maximum shelf life and pest prevention, store nuts in airtight containers in the refrigerator or freezer.

Identify the Culprits: Understanding Common Nut Pests

Before you can effectively tackle the problem, it helps to know your opponent. The 'worms' found in nuts are not true worms, but rather the larvae of common pantry pests. Two of the most frequent offenders are the Indianmeal moth and the navel orangeworm, whose adult forms lay eggs on nuts either in the field or during storage. The eggs hatch into small, creamy-white larvae that then feed on the nutmeats.

The Navel Orangeworm

Larvae appearance: Reddish-orange when young, becoming a creamy white as they mature.
Damage: Feeds on the nutmeat, leaving behind webbing and frass (excrement). This also increases the risk of aflatoxin-producing molds.
Common hosts: Most troublesome for almonds, pistachios, and walnuts.

The Indianmeal Moth

Larvae appearance: Small, dirty white caterpillars.
Damage: Feeds on nuts and other stored grains, often leaving behind a distinctive webbing.
Common hosts: A wide range of stored products, including nuts.

Step-by-Step Guide to Removing Worms

Once you’ve identified an infested batch of nuts, it's critical to act quickly to prevent the pests from spreading to other pantry items.

1. The Isolation Process

Immediately seal the infested nuts in an airtight bag or container. This contains the problem and prevents any potential adults from escaping and laying eggs elsewhere.
Conduct a thorough inspection of your entire pantry. Check other dry goods like flour, grains, and cereals for any signs of larvae or webbing.

2. Choose Your Treatment Method

There are two main strategies for killing the larvae and eggs: using freezing cold or applied heat. You must kill all life stages of the insect to prevent re-infestation.

The Freezer Method

Freezing is a reliable and safe method for sterilizing your nuts without altering their texture or flavor significantly. This process kills any existing eggs, larvae, and adult pests.

Place the sealed bag or container of nuts in the freezer.
Set your freezer to 0°F (-18°C) or lower.
Leave the nuts frozen for at least four days to ensure all life stages are killed.
After freezing, allow the nuts to return to room temperature gradually to prevent condensation, which can lead to mold.

The Oven Heat Method

For nuts that are still in their shell, or for those who prefer not to use the freezer, a low-temperature oven can be effective.

Preheat your oven to approximately 140°F (60°C). Do not exceed this temperature for too long, as it can affect the nuts' oil and flavor.
Spread the nuts in a single layer on a baking sheet.
Heat for 15-30 minutes. Monitor them closely to prevent roasting.

3. Cleaning the Nuts

After treatment, whether with heat or cold, you need to clean the nuts of any remaining debris.

Spread the nuts out on a clean surface. For in-shell nuts, you can perform a flotation test by placing them in water; infested nuts, being lighter, will often float.
Pick through the batch and visually remove any discolored, damaged nuts, or visible frass and webbing.
For shelled nuts, a quick rinse in a colander under cold water can wash away any debris. Be sure to dry them thoroughly in a low-temp oven or with a dehydrator before storage to prevent mold.

4. Sanitizing Your Storage Area

Once you’ve dealt with the nuts, you must deep-clean your pantry to eradicate any lingering pests. A single spilled nut or forgotten grain can restart an infestation.

Remove all food items from the pantry or cupboard.
Vacuum all shelves, crevices, and corners thoroughly to remove any hidden eggs or larvae.
Wipe down all surfaces with a solution of equal parts white vinegar and water, which serves as a natural repellent.

Prevention is Key: Long-Term Nut Storage

Airtight Containers: Always store nuts and other susceptible pantry items in glass jars or thick, airtight plastic containers. This prevents pests from getting in and stops any potential future outbreaks from spreading.
Refrigerate or Freeze: For long-term storage, keeping nuts in the refrigerator or freezer is highly recommended. The low temperatures inhibit insect and mold growth and prevent the oils in the nuts from going rancid.
Bay Leaves: Some people swear by placing a few dried bay leaves in their stored nuts and grains. The scent is said to repel weevils and other pests.
First In, First Out (FIFO): Practice a system of using older stored goods first to ensure nothing sits long enough to develop an infestation.

Method Comparison: Freeze vs. Heat


Feature	Freezer Method	Oven Heat Method
Effectiveness	Kills all life stages (eggs, larvae, adults).	Kills most life stages if correct temperature is maintained.
Time Required	4 days minimum.	15-30 minutes.
Risk of Flavor Change	Low, if nuts are properly sealed to prevent absorption of odors.	Potential for roasting or scorching if not monitored carefully.
Ideal for	Large batches or long-term preservation.	Immediate use or smaller quantities.
Post-Treatment Care	Ensure gradual temperature change to avoid condensation.	Let cool completely before storage.

Conclusion

Finding worms in your nuts is an unpleasant surprise, but it does not mean your entire pantry is ruined. By isolating the infested items, applying either cold or heat treatment, and then thoroughly cleaning and sanitizing, you can resolve the issue effectively. The key to long-term success lies in proper, airtight storage and proactive prevention techniques. With these steps, you can confidently enjoy your nuts without the worry of uninvited guests. For more extensive information on controlling pantry pests, the University of California's IPM program offers excellent resources, particularly for crops like pistachios, almonds, and walnuts.

Frequently Asked Questions

The 'worms' are actually the larvae of pantry moths, such as the Indianmeal moth, or weevils like the navel orangeworm. These insects lay their eggs on nuts, and the larvae emerge to feed on the nutmeats.

While accidentally consuming a larva or a contaminated nut is not typically harmful, it can expose you to harmful contaminants such as mold. It is best to discard any nuts that are visibly infested and thoroughly clean any salvageable nuts after treatment.

Yes, if the infestation is minor, you can often save the remaining nuts. Treat the entire batch with cold or heat to kill all life stages, then clean and store them properly. If the infestation is widespread, it's safer to discard the entire batch.

Yes, freezing is a highly effective method for killing insect eggs, larvae, and adults. By placing nuts in the freezer at 0°F (-18°C) for at least four days, you can sterilize them and prevent new pests from hatching.

The best way is to store nuts in a freezer-safe, airtight container in the freezer. For shorter storage, use airtight containers in a cool, dark place. For added protection, include a bay leaf in the container.

Microwaving can kill pests but is a less consistent method than freezing or using an oven. The heat distribution can be uneven, potentially leaving some eggs or larvae alive while scorching the nuts. Using the freezer or low-temp oven is safer and more reliable.

If an infestation has spread, you must take everything out of the pantry, dispose of all infested items, vacuum thoroughly, and wipe down surfaces with a vinegar solution. Store all unaffected dry goods in new airtight containers.