DIY Fermenting Weights

Posted on Tuesday, October 20, 2015 | By Nicole Easterday |

Make your own DIY Fermenting WeightWhether you're craving salt, trying to add more live cultured food to your diet or just love fermented foods like sauerkraut, you're in luck! It's so easy to make your own at home and a ridiculously safe way to add more probiotic foods to your diet.

We teach a lot of fermenting classes here at FARMcurious and one of the most common questions is whether or not homemade fermented foods like pickles, sauerkraut and other vegetable ferments should be weighted down and, if so, what to use as a weight.

First of all, let’s talk about why you would need a weight to ferment a vegetable.

Most traditional methods of lacto fermentation (crocks, barrels, etc) require keeping the produce submerged under the brine in order to protect it from bacteria that would otherwise rot the food. The majority of fermenting crocks come with a weight that fits perfectly inside.

Even if you’re fermenting within a smaller environment like Mason jar you’ll need a weight to keep the produce submerged and that’s frequently where the confusion starts.

In a closed system like the FARMcurious Fermenting Set (or other airlock system) a weight is generally not needed because the airlock keeps the environment oxygen-free and safe from contamination of yeast and mold. This is because the carbon dioxide produced during fermentation rises up through the vegetables and pushes out any oxygen that remains at the top of the jar.

Without oxygen, you can’t grow yeast or mold!

However, when you pack shredded vegetables tightly into an airlock system, the carbon dioxide has a more difficult time escaping through the layers of produce and will tend to push the layers up instead of pushing the oxygen out. This not only keeps the carbon dioxide from being able to push out the oxygen, but it can also press the produce up into the airlock, causing other issues (like a moldy airlock - yuck!). You can read more about it here.

For this reason, we actually do recommend using a weight in the FARMcurious Fermenting Set - and other airlock systems - when you’re making sauerkraut or anything else calling for shredded vegetables.

We sell some beautiful handmade fermenting weights made right here in Oakland but for those of you who are more budget sensitive, I have a great alternative. We’re obviously all about DIY around here so why not make your own weights?

We’ve heard other ‘experts’ express such an array ideas about what could be used as a homespun fermenting weight that we decided it’s time to discuss the issue.

Now let’s address what we DON'T advise using as a fermenting weight.

Ziploc bag filled with brine or otherwise

Ziploc bags are made of plastic and fermented foods are acidic.

We recommend avoiding plastic when it comes to food as a general best practice but especially when the food is acidic. Acid can break down the plastic, causing it to leach sketchy chemicals into your otherwise healthful food. With so many other great, clean options, it’s just not worth the risk.

Unidentified rocks from your garden, boiled or otherwise

This seems like such a wonderful, natural choice and potentially aesthetically appealing to earth-sign-types like me. The idea is to get a rock from your yard and boil it to kill any bacteria then to place it on top of your veggies. The problem is that most of us aren’t geologists and don’t know what the rocks in our yard are actually composed of. I’ve heard of rocks changing the color of sauerkraut, crumbling into the food and worse, affecting the flavor. Unless you know exactly what it is, we recommend skipping this one.

Random knick-knacks found around the house

Though it might be cute and awfully upcycle-y to sink granny’s souvenir from her single days into your fermentation crock, it could also be dangerous. The most common culprit is lead. While you can get lead test strips from a hardware store to test, it sometimes takes chipping the glaze to find out whether it’s safe or not. We have some better suggestions to try!

What CAN be used as a homemade fermenting weight?

We’ve put together some easy DIY fermenting weights you can create from food items commonly found in the kitchen.

Cabbage Core Weight

This is a favorite, particularly if you’re making sauerkraut, since you’ll already have a cabbage core on hand.

Cut the cabbage in half then cut the core out in a little wedge. You can then trim it to fit your jar size. A square works fine but you could also cut a circle if you’re feeling fancy. Just be sure to notch a hole in the center of the circle so you have a way to pull it up when you’re done fermenting! If you need a larger size than the core provides simply leave some outer leaves on for extra coverage.

Apple Weight

Apples are inexpensive and easy to find year-round. You may even have one sitting on your counter right now!

Trim the curved edges off the apple - just enough to allow it to fit inside your jar opening. Carve out the core of the apple, creating a hole through which to grasp the weight when you’re ready to remove it.

Daikon Radish Weight

Fermented radishes are truly one of our favorite things to eat in the FARMcurious office. We’re always looking for excuses to have more around.

Slice a 1” thick piece out of the portion of the radish that is closest to the diameter of weight you need (daikons tend to be tapered so you can choose the location based on the width). Again, be sure to cut a circle from the center of the radish disk. You may find you need to trim the edges more once you begin trying to fit it into your jar.

Nested Jar Weight

One inorganic option is to nest a smaller-sized Mason jar into the mouth of the jar you’re fermenting in. This option works very well if you’re fermenting in an open Mason jar without an airlock. One added bonus is that you can periodically press on the top of the inner nested jar to compress the veggies and check the brine level. If brine is evaporating (as can happen in an open system) you can just pour more in the top as needed. The glass in a Mason jar is non-leaching, chemical-free, food-save and clean.

I hope this tutorial helps at least a few people move away from the ubiquitous Ziploc bag trick. We work so hard to feed our bodies good food - why throw it away so easily?

Let us know your tricks for homemade DIY fermenting weights!