Weevils In Oatmeal: Ways To Keep Them Out

It’s not news anymore that bugs like weevils are one of human’s biggest pantry nightmares. Granary weevils in particular always have a way of showing up in oatmeal and ruining your cereal and grains.

Weevils bore holes in foods and lay eggs which develop from larva into pupae. Their rate of maturity and reproduction also factors into how annoying a pest they can be. Although people around the world eat insects, westerners find it disgusting.

Moreso, it already feels squeamish thinking about the possibility of feasting on a bowl of oatmeal with weevils hovering around. This article explains how you can keep weevils out of your pantry food as well as other relevant information you should know.

Is it safe to eat weevils-infested oatmeal?

Yes. Weevil-infested oatmeal is completely safe to eat. Weevils are not poisonous so they do not harm us. As a matter of fact, once you cook your oatmeal, the weevils, larvae, and eggs become a source of protein for your body just like meat.

Live weevils in your oatmeal show that it is free of pesticides. Conversely, if you find dead weevils in your oatmeal, it is likely that your oatmeal contains pesticides and is not safe to eat.

Apart from the psychological factor, there’s really no problem that arises from eating weevils. The boiled water added to oats kills all bacteria in weevils making it perfectly okay to consume.

SEE: Can You Freeze Oat Milk

How do weevils get into food?

Weevils are notorious insects known to infest sealed or covered food. And it can be really confusing and annoying trying to figure out how they get in there.

The truth is, there’s nothing wrong with your oatmeal. Just like any other pantry pests, weevils infest and feed on cereals, grains, nuts, seeds, beans, corn, and the like. Oatmeal is particularly infested by reddish-brown granary weevil.

Unlike many other insects, granary weevils live and feed inside the food. Female weevils burrow into grain kernels and deposit eggs in them, sealing them up. When the egg fertilizes, the larvae eat the grain inside until it matures into pupae.

The pupae or adult weevil bore a hole out of the grain and emits pheromones, to alert male weevils of its presence for further reproduction.

So, weevils do not get into your oatmeal or food, it’s already present in them right from storage before you buy them. And you can only see the weevils, not the larvae because they are very tiny and live inside the grain.

SEE: Does Oat Milk Go Bad

How to keep weevils out of your food?

It can be really frustrating and annoying to open your bag of grains or cereal only to find weevils parading freely in them. You might have even ingested unseen eggs and larvae of bugs and weevils once without knowing.

Weevils’ eggs mature in as fast as 3 days. Hence, they multiply very quickly and may contaminate foods that are stored for a long time. Spraying pesticides on your food is not an option so, it is very difficult to exterminate them.

That said, what measures can you take to reduce the troubles of dealing with weevils and pests in general? Consider doing the following:

1. Know what weevils are

Knowing what weevils are will make it easy for you to spot them in your pantry. Weevils are tiny beetles that come in a variety. The type that infests oatmeal is granary weevils.

Granary weevils are red-brownish in color. They cannot fly and you’d hardly find them roaming within your pantry instead they stay inside the food bag or containers. They grow up to 4.8mm long and their body consists of a head, abdomen, and thorax.

One female weevil can lay hundreds of eggs that mature into adults in days. That’s why they infest food very quickly. Thankfully, you can still eat weevil-infested food if you do not feel squeamish about it.

2. Keep your kitchen & pantry clean

The kitchen is where you do all the messy stuff. Chopping meat, doing the dishes, cooking food, trashing diets, etc. It’s easy to leave your kitchen unclean after going through the hassle of cooking.

This can attract pests and insects into your kitchen and pantry. Your best bet is to keep your kitchen clean at all times. Try to wash off oil and food spills from the kitchen with soap and water or disinfectants after cooking.

Do the dishes as fast as you can, throw out unused water, and clean your microwave, toaster, fridge, and kitchen tools from time to time.

SEE: Transformative Techniques to Clean Your Kitchen

3. Carefully examine foods before buying them

When you find weevils or bugs in your food, it is most likely that the food was infested before you brought it home. When you visit a store to get cereals or grains, ensure that you check them properly to see that there’s no movement of insects.

Take note of the package to know if there are openings around it. If you notice the seal is broken or you see a small hole in it, it is possible that bugs have made their way into the food.

Additionally, check the expiry date of the product and ensure that they are not close to expiration. It will be in your best interests to get branded reputable oatmeal or grains to avoid buying low-quality products.

I’ll also advise that you obtain grains or oatmeal that you’re able to finish in a month or two. Pests’ infestation is more likely for food that sits in your pantry for a very long time.

4. Store your foods in airtight containers

It’s easy for pantry pests like weevils to sneak into your food through tiny spaces or holes. Leaving your food in their boxes exposes them more to this.

A better solution is investing in quality airtight plastic, glass storage, or metal containers. You can acquire mason jars from the market to store grains while oat can be stored in plastic containers.

To preserve your food better, you can store oats, flour, cookies, and cornmeal in the refrigerator or freezer for at least four days before keeping them in the cupboard. This helps to kill all the eggs and larvae present in the food package.

SEE: Food Storage Mistakes You Should Avoid From Now

5. Heat up grains

You can prevent infestation of whole grains like rice by heating them up in the oven. Start by rinsing the grain thoroughly on a strainer under clean water with your hands.

After that, heat up your oven to 60-degree Celsius or 140-degree Fahrenheit, put the grains on a baking sheet, and place it in your oven for fifteen minutes.

Take it out afterward and let it cool off before transferring it to your container. This kills any egg or larvae present in your food and prevents it from further infestation.

6. Use repellents

Some herbs are helpful for chasing weevils and bugs away from your pantry. A good example is bay leaves. Bay leaves add fragrance to food but bugs hate the smell.

Simply spray or sprinkle them around your cupboard, near your containers, or even inside open bags of grain and flour. If you can’t find fresh bay leaves, dried ones also give the same results.

Another excellent repellant is white vinegar. Once you’re done cleaning your shelves and cupboard with soap and water, take a piece of cloth and wipe through again with white vinegar. This kills any weevils or bugs that are in the pantry.

You can also use cloves if it’s the first time your food gets infested. Sprinkle the oil around your pantry and cupboard and it will kill any insect in contact.

Black pepper also works when you put them in grains. Lastly, you could put a matchbox close to your food but make sure it is out of children’s reach because of the sulfur present in it.

SEE: Flour Beetle In Bedroom Prevention and Solutions


What type of foods do weevils infest?

Weevils infest grains like rice, wheat, and oats.

Do airtight containers keep weevils out?

Yes. Airtight containers help to stop weevils from entering your food.

Can weevils get through paper bags?

Unfortunately, granary weevils can chew through paper packages.

Do weevils affect food?

Yes. Weevils feed inside grains seed thereby reducing the quality of the food.


Weevils and bugs are grain companions. It’s almost impossible to stop them from infesting rice, wheat, oats, and the like. If you select products that are close to expiration, opened, or low-quality, then you risk having more of them in your pantry.

What you should do is always select branded, good-quality, and unsealed oatmeal. Then, keep your kitchen clean by taking out the trash, washing dishes, and clearing all stains and spills on the floor, countertops, slab, etc.

Also, keep your food in airtight plastic, metal, and glass containers. Go further to use repellants like white vinegar, bay leaf, and the likes to control pest infestation. And buy cereals that you can finish at most 3 months or less.

Finally, you would find the article on the differences between oats and oatmeal helpful.

I hope this article helped you. Thanks for reading.