Fermentation Weights How to Keep Veggies Submerged
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Fermentation Weights: How to Keep Veggies Submerged

Don’t you hate it when you’ve waited patiently for a batch of fermented vegetables to be ready to eat, and when you open the lid, you find it covered in a fuzzy mold.

“Why did my fermented vegetables grow mold and spoil?”

“What did I do wrong?” are just a few questions that pop to mind.

Mold happens when oxygen comes into contact with the vegetables that break the surface of the brine.

“How do I prevent moldy fermented vegetables from happening again?”

Fermentation weights are an easy fail-safe method of preventing spoiled batches of your favorite fermented veggies.

This article will cover why vegetables need to be submerged below the brine. Ideas on how to make your own fermentation weights, what to avoid using, and recommend some high-quality fermentation weights that you can easily order online.

Why do vegetables need to be submerged in brine, you may be wondering?    

To prevent the vegetables from rotting, they must be in an oxygen-free environment (below the brine).

The carbon dioxide that is produced during the fermentation process rises up through the vegetables and pushes the oxygen that remains to the top, above the brine level.     

The vegetables that peak above the brine come into contact with the oxygen and become contaminated from bacteria, Kahm yeast, and sometimes mold.     

Mold and yeast can’t grow without oxygen. 

Fermenting is a great way to increase your intake of probiotics and boost overall health. Just make sure you keep the fermenting foods submerged below the brine so the end result is safe to eat.

The following are some easy DIY ideas for making your own fermentation weights at home.

Fermentation weights can be created from the food you are fermenting, such as cabbage leaf, cabbage core, and carrot sticks.

Cut cabbage leaves big enough to cover the inside of your fermentation vessel. You can layer strips of carrot or zucchini on top of the leaves for extra coverage and push everything down.

Carrot sticks, you can easily criss-cross them over the top of the veggies to push them below the brine.

Apples, daikon radish, or onion all can be used in a similar fashion.

Make sure to discard the veggies you use as a weight when you finish the fermentation process, replace them as needed, and NEVER eat them.

You can also use a small ziplock bag filled with water (or brine) to weigh down the vegetables.

Pebbles or rocks are often recommended, just make sure you wash them as best as you can first and avoid using limestone because the calcium in it can react with the acid in the ferment.

Everyday kitchen items such as the following can serve as weights too:

  • Shot Glasses
  • Baby Food Jars
  • Espresso Cups
  • Dipping bowl
  • Stainless Steel Portion Cups

Avoid using the following items as fermentation weights.

Avoid using knick-knacks from around the house, you don’t want to accidentally contaminate your ferment with lead. That goes for copper and brass objects as well. The acid and salt from the fermentation process can corrode and destroy both copper and brass, causing it to leach into the food.

What Fermentation Weights Can You Buy?

There are many varieties of fermentation weights to choose from online. 

However, from experience I recommend sticking to glass weights because they are non-porous, which prevents smells and flavors from transferring from batch to batch.  These are great for smaller batches of fermented foods.

With that being said, I do recommend the Humble House SAUERKROCK Fermentation Crock with weights because it comes in three larger sizes, 2 liters, 5 liters, and 10 liters.  

Sometimes you just want to make a huge batch of kimchi or sauerkraut and messing with 20-quart size jars just seems impracticable.  Go Big or Go Home. Right.

The weights are not glazed but very cleanable if done correctly. 

Just be sure to pay attention to the size of the glass weight you are buying. The first time I ordered glass weights they were for a wide mouth jar, and at the time I only had regular size jars on hand.   Not a big problem, since mason jars are generally pretty easy to find. But, just a little heads up: pay attention to the size of jar you are trying to fit the glass weights into.


6-Pack Easy Fermentation Glass Weights with Handles by Siliware

The Weights have Handles for Keeping Vegetables Submerged During Fermenting and Pickling, Fits Any Wide Mouth Mason Jar, FDA-Approved Food Grade Materials

Masontops Pickle Packer Vegetable Tamper & Pickle Pebble Glass Weight Fermentation Tool Set

Masontops Fermentation Tool Set

Premium Quality, Custom Designed For Mason Jars, Finger Grip For Easy Removal – Available in wide-mouth and regular-mouth versions.

Humble House SAUERKROCK Fermentation Crock with Glazed Weights

Available in three sizes: 2 Liter (0.5 Gallon), 5 liters (1.3 Gallon), or 10 liters (2.6 Gallon) German-Style Water Sealed Jar for Fermenting Sauerkaut, Kimchi, Pickles and More

Hopefully, this list of ideas on how to keep your vegetables under the brine will inspire you to keep on fermenting. Take a minute to check out all the other supplies you’ll need, pick a recipe, and continue your fermenting journey!


Hello! I’m Katie, mom, hobby fermenter, gardener, canner, and boundless experimenter. Here at Fermenters Kitchen, our team of enthusiast aims to encourage readers to embark on a fermentation journey with us, one bubbly jar at a time.