Can I Ferment in a Plastic Container?

Once you start fermenting, it’s hard to not get addicted. It’s such a simple, fascinating way to create new flavors and dimensions to ordinary ingredients, and it can completely transform your cooking.

Naturally, as you get more involved in this hobby, you want to scale up your ferments into larger and maybe more specialized containers. But large glass containers, to say nothing of wooden wine or pickle barrels, can be expensive. So, can you ferment in a plastic container?

Can You Use Plastic Containers for Fermentation?

Because fermentation is a natural process, the microorganisms responsible for fermentation can live as easily in a plastic container as any other material. However, plastic is not preferred for fermentation for a few reasons:

Difficulty of Cleaning and Sterilization

Generally speaking, it is easier to clean and sterilize smooth, nonporous materials like glass, ceramic, and stainless steel.

Prone to Staining and Absorbing Odors

Plastic is prone to staining and may retain odors after fermentation.

May Harbor Unwanted Bacteria

Fermentation is all about cultivating the bacteria you want and preventing the bacteria you don’t want. Because plastic scratches and scuffs easily, those small irregularities can trap and hold unwanted bacteria, which may affect the quality of your ferments.

May Have Unwanted Chemicals

Depending on the type or grade of plastic, it may contain unwanted or unhealthy chemicals. These chemicals may degrade and leach into your ferments, mainly when liquids are very acidic, very warm, or stored for long periods.

If You Must Use Plastic

If you want to ferment in a plastic container, here are the essential things to consider:

Choose a High-Quality Food-Grade Plastic

Avoid any plastic with BPA or BHA. Choose HDPE, LDPE, polypropylene, or polycarbonate.

Clean Gently

Clean plastic fermentation containers with gentle, nonabrasive cleaners to avoid scratching the surface. Bacteria can colonize very easily in small dents and scratches on the surface of plastic containers.

Sterilize Between Uses

Remember that cleaning and sterilizing are not the same. Avoid soaking plastic containers in vinegar or bleach solutions because they may degrade the plastic. Instead, soak plastic containers in a 3% hydrogen peroxide solution for 15 minutes, or spray them with a 70% isopropyl alcohol solution.

When you choose high-quality plastics and clean and sterilize them properly, you can ferment foods in them.

Fermentation FAQs

Can You Make Sauerkraut in a Plastic Bucket?

A plastic bucket is actually an excellent choice for sauerkraut if you don’t have the traditional earthenware container. Make sure your bucket is made of food-grade plastic, has a sturdy construction and rigid sides, and an air-tight lid. A food-grade plastic bag inside the bucket to hold the cabbage and brine is a great way to ensure that the cabbage remains submerged in the brine and that no air is allowed into the fermentation process.

Can You Ferment Pickles in Plastic?

Like sauerkraut, pickles should never be fermented in metal, so earthenware is traditional. However, a food-grade plastic container is a great alternative.

Because pickles need to be covered with 1-2 inches of brine, it is usually necessary to weigh them down. Ensure that your plastic container is large enough for you to use a plate, weight, jar, or something else to keep them submerged in the brine.

If your plastic container isn’t the right size for a plate or weight, you can use a plastic bag as an alternative. Take a bag made of food-grade plastic and place some pickling brine inside the bag, sealing it tightly. Then use the bag of brine as a weight to hold down the pickles. The bag is loose and flexible, so it fits in various containers, and filling it with brine protects your ferment in case of punctures or leaks.  

Can You Ferment Kimchi in Plastic?

A: Sharp observers may note that no less than the legendary Maangchi herself makes kimchi in a plastic container in her Easy-to-Make Kimchi recipe. Remember that if you make kimchi in a plastic container, the container will smell like kimchi forever. Most people choose to dedicate a specific set of containers for kimchi so the smell does not mix with other foods.

Related read: What Causes Kimchi to Ferment?

When making kimchi in a plastic container, it is essential to leave enough headroom in the container. If you leave the lid on your plastic container partially open to allow gases to escape, likely, your entire refrigerator will also smell like kimchi. Many Koreans use a dedicated kimchi refrigerator specifically designed to aid fermentation and contain the aroma.

Can You Ferment Wine in a Plastic Container?

Making wine is a two-step process: You need a container for primary fermentation and a second container for aging. As a rule, you can ferment wine in food-grade plastic containers (and you can even buy specialty plastic wine fermenters with room for the must), although it is usually recommended for red wines and smaller batches. Most plastic containers have a very large surface area that increases oxidation risk during the fermentation process.

While technically you can also age wine in plastic containers, most wine experts recommend against it. Because wine is acidic and needs to age for long periods, there is a risk of elements leaching from the container into the wine. This is true for fermenting kombucha as well (click here to learn more).

Can You Brew Beer in Buckets?

You can brew beer in food-grade buckets, and it’s extremely common for beginning homebrewers to start out that way. Like wine, the large surface area of the bucket increases the risk of oxidation, so beer should not be kept in a plastic bucket for longer than 2-3 weeks. 

In Summary

Plastic is affordable, available, and easily accessible. While glass and ceramic are the preferred containers for fermenting and do have many advantages, there is no reason you can’t ferment nearly anything in plastic. Always make sure that you are using high-quality food-grade plastic, and make sure to properly clean and care for it. A plastic bucket is a great way to start or scale up a fermentation hobby.