Brine vs Mash Fermentation

Brine vs mash fermentation is an age-old debate that is generally highly contested in the fermentation forums and communities. Which one is superior? Honestly speaking, it depends on several factors. 

Brines and Mashes - What is The Difference? 

To understand the difference, let’s first talk about how salt percentages play a role in fermenting. When fermenting LAB (Lactobacillus or Lacto for short) you’re adding salt, not sugar or yeast (those are different types of ferments), to your brine or mash. The general rule is between 2-5%. You don’t want to go any lower than 2% because it makes it easier for other microorganisms to compete for resources. Lacto is a salt-tolerant organism and can win the battle a lot easier in that kind of environment. On the other hand, at 5% you are getting more towards a very salty finished product. Many people have quite different schools of thought on what percentage to use with certain things, and it should be something you experiment with to determine for yourself. 

Brines

Brines are very simple. Salt and water. Your percentage of brine is calculated on how much water you are using. Personally, I use a website that has a lovely calculator you can use to calculate your brine percentages.

Some people within the community say that your brine should be the weight of the vegetables AND your water, as it would give you a true x% of the total batch. I honestly do not worry about it as adding vegetables to your brine drops the percentage by a negligible amount. Using a brine style of ferment comes with certain risks. There are several factors to consider:

Weights: You must use weights to hold your vegetables under the brine. If you have vegetables floating at the surface, you will have a high likelihood of mold at the surface as it takes several days for the pH to drop. 

Headroom: Headroom is important as your ferment will expand and bubble. If you don’t have sufficient headroom your brine could clog and come through the airlock. For a standard mason jar, 1-1.5 inches (from below the threads of the jar) is usually sufficient for headroom.

Mashes

Mashes are just as straightforward. Mash/cut/chop/shred your vegetables to pieces and simply add salt based on the total weight of your vegetables. Have 5 lbs. of peppers? Chop them up nice and fine and add 68g of salt for 3% salinity. With mashes there is still the headroom concern (I recommend about 2 inches from below the threads of the jar), however there is one factor that needs to be considered you don’t have with brines - a salt cap.

Salt Cap: Because mashes are not submerged under a brine (or with a weight), they are very susceptible to mold growth as the ferment starts up and begins filling the headroom with CO2. Depending on the size of your container, you can take your total weight of salt and use half in the mash and half as the salt cap.

A salt cap creates such a high salinity environment that nothing can grow or survive. Over time as the product ferments and the pH drops, the salt cap is absorbed into the mash. When it does get absorbed, mold growth isn’t an issue as the headroom is filled with CO2. 

Before fermentation, a Salt cap is applied to stave off unwanted microbial growth.

 So which is better in the brine vs mash fermentation debate? Each one has its use and would depend a lot on what you want the finished product to be.

Here a few of the pros and cons of each format from my personal experience in fermentation:

Pro's and Con's of Brines 

• Good to use for whole vegetables such as cucumbers and green beans. 
• Need a little more equipment (weights) to get started. 
• Potential of vegetables escaping the weight and floating to the top. 
• Brine can be added back in the end product to thin out your blend.
• More susceptible to yeast or pellicle build-up.

Pro's and Con's of Mashes

• Can get more peppers in one batch. Takes up less space in the jar. 
• Better to use when you’re blending your final product.
• Doesn’t have brine to add back in, needs another liquid to thin out your sauce.
• Don’t have to worry about floaters in the brine escaping the weights. 
• Overall less maintenance. 

What's the Verdict?

For hot sauce production, the mash format wins out. It’s a lot less maintenance and worry than a brine, plus we can produce a lot more in one sitting in the same size bucket. Brine has its place for whole vegetable ferments (Half sour pickles, radishes, garlic, green beans, etc.). 

If you have more interest in the details of this format, feel free to read up here on How to Get Started in Fermentation. 

So brine or mash? Which would you prefer?