Before I discuss the issue of whether mold can grow in the freezer with you, first, I need to mention something, just to lay a proper foundation.
If you live in a place with high humidity, well, you will notice that mold tends to grow in the warmer seasons. In winter, it can be conspicuously absent.
In fact, most people think that mold disappears in winter. BIG MISTAKE!
Unless you fumigate your house when you have had a mold infestation, this fungus does not disappear with winter.
However, it stays dormant as the temperatures are too low for it to thrive. Also, the indoor humidity level in winter is usually low, and mold thrives in a humidity level higher than 60%, and a temperature range of 60 to 80° F/15.5 to 26.64° C.
For mold to grow, the above temperature and humidity levels must be present. And in winter, they are not. That is why the mold goes dormant.
Can mold grow in the freezer?
The recommended freezer temperature is 0° F/-18° C. At least this is what the FDA recommends for your food storage. The recommended refrigerator temperature is at or slightly lower than 40° F/4° C.
The recommended walk-in freezer temperature is -10°F/-23°F, which is slightly lower than that for your home fridge.
As you can see in the above figures, the temperatures are too low for mold to grow. While there will be dampness, all types of mold require the right temperature to grow. In addition, the mold grows at 60 percent humidity, or higher.
To answer the question, mold can grow in the freezer. For instance, if the freezer is disconnected for a few days, or even hours, mold can start to grow.
In the article on mold and humidity growth chart, you can see that some varieties of mold can grow in a few hours, under the right conditions.
Perhaps you are wondering where the mold will come from. It comes from some of the foods that you store in the freezer. They leave the mold behind, and then when the conditions are right, it grows and colonizes.
Can mold grow in a refrigerator freezer?
Despite the cold temperatures, mold can grow in your refrigerator freezer. If it can find its way into the refrigerator, then it will grow.
This does not mean that it will grow immediately since there is the matter of the low temperature. However, as soon as the temperature allows, the fungus will start to grow.
Mostly, the mold gets inside the freezer via the food that you store there. If you look around the web, you will see many people complaining about the food they keep in the freezer growing mold.
Usually, this happens when the food already contains mold. It also leaves some of that mold in the freezer and so you have an unending cycle of mold growing on your food, anytime you keep it in the freezer.
Most molds only thrive in warm temperatures. However, this allergen is also stubborn, and it can survive in very low temperatures. In fact, today, some strains can grow in the cold temperature of the refrigerator.
The coldness of the freezer does not kill the mold spores. The mold spores become inactive, and when the conditions are right again, they sprout and colonize.
What causes mold to grow in the freezer?
Knowing the cause of the fungus in the mold can enable you to prevent it. There are a few causes, which are as follows:
1. Wrong defrosting process
Defrosting the freezer when the door is closed makes the environment too warm and humid, and that is exactly what the mold needs to grow.
To defrost your freezer, open the door until the process is done.
2. Having mold around the home
If you have mold in your home, it will find its way into the freezer, no matter how careful you are. While the freezer can also get mold from the food you bring from the store and the market, that from the home is notorious. Get a fumigation company to rid your house of mold.
3. Power blackout
If there is a power blackout, it means the fridge stops running and the temperature rises. Therefore, if there is dormant mold in the freezer, it starts to grow. If the power outage lingers too long, the higher the chance of the mold growing.
If you unplug the fridge and forget to plug it back, the freezer will not freeze the air, so if there is mold, it will start growing.
4. Opening the fridge door too often
Every time that you open the fridge or freezer door, more warm air from outside gets into the fridge. This increases the chances of the mold growing inside.
When the freezer freezes the air inside, it suppresses the mold from growing. But this is not going to happen when you keep opening the door, and letting warm air get inside.
5. If the freezer fails to reach the required temperature
Kitchen appliances are susceptible to malfunctioning, and the fridge is not any different. The freezer should reach certain temperatures. If it does not, it might not make the air cold enough to suppress the mold and prevent it from growing.
If you find that your food is spoiling too much, it is growing mold, or the motor of the freezer is too loud, the freezer might have failed.
Call a technician to service the fridge and find out what is wrong with it.
How to stop mold from growing inside the freezer
Now that we know that mold can grow in the freezer, you need to know how to prevent that from happening.
Remember, having mold in the fridge means it will find its way to the food. Consuming such food will expose your family to nasty symptoms of mold exposure.
Here are a few ways to keep the freezer safe from mold:
1. Remove mold from your house
For your freezer to have toxic black mold or any other type of this fungus, it must come from somewhere.
Do you have mold infestation in the basement, bathroom, kitchen, or in the closet? If yes, the mold spores float in the air, to other places, including the fridge.
If you realize that you have mold in your home, start by lowering the humidity level. It is always a good idea to check the indoor humidity using a hygrometer.
Some molds can also be hard to identify, so you should call a fumigation company. They will get rid of all the dangerous types of mold, and even the mild ones.
2. Sanitize food before storing it
The food that you buy from the stores can also introduce mold into your freezer. In fact, this is where most of the freezers get the fungus from.
If you are sure there is no mold in your house and in the fridge, clean the food that you bring from the store before storing it.
Do not trust the perishables that you get from the market. Clean them with water, and then dry them before storage in the fridge.
3. Clean the fridge with vinegar
If you can leave vinegar on mold overnight, you can use vinegar to clean the fridge. This is going to get rid of the mold.
In the same way that cleaning a humidifier with vinegar kills mold, it will kill it in the fridge too. Fumigation companies use high heat to kill mold, but you cannot use heat to clean your fridge. Thus, use vinegar and water.
Generally, it is recommended to deep-clean your fridge three to four times a year. However, this is not cast in concrete. If you want to clean it deeply once every two months, go ahead and do it. If you suspect that you have mold, deep-clean the fridge more often.
Deep-cleaning means you will have to remove everything from the fridge, defrost it, clean it with a vinegar-water solution, and then give it time to dry. But it will be worth it.
4. Clean the fridge with baking soda
Baking soda is one of the best cleaning products that we all have at home. You can use it to clean your fridge, and it will help to kill the mold.
You are not going to use baking soda alone to clean the fridge. Rather, you are going to use it after cleaning the fridge with the vinegar.
Let the fridge dry and then make your baking soda paste. Apply the paste inside the freezer and the refrigerator, and let it stay some time, before cleaning it off with clean water.
Give the fridge some time to air-dry completely, before you plug it back into power, and return your perishable foods to the freezer.
Mold can grow in the freezer, and it can come from different sources such as the food items, or from the mold spores in your house.
If you start noticing mold on your oranges, bread, and other foods, you need to unplug the fridge, remove all the food items, and give it a thorough deep cleaning with vinegar, soapy water, and baking soda.
While I can reiterate here that mold does not grow in cold temperatures, well, it can grow, albeit very slowly in the freezer. Freezing won’t kill the fungus, so you will have to get rid of it.
Check the fridge, and the food stored there often for signs of mold. Also, give it a regular deep cleaning every couple of months.