Brine is used in fermentation to keep the contents safe. Water acts to keep aereobic (air-loving) microbes out of the party, and salt regulates which microbes will survive and thrive. Adding the right amount of salt to water will enable the microbial magic that is fermentation!
At the bottom of the jar of your fave ferment? Fear not! There are many things you can do with leftover brine.
Whether it is from pickles, sauerkraut, or kimchi, extra brine is packed with the same probiotics as the veggies (bacteria are swimmers!), salty flavor, and of course the organic acids that developed during fermentation. It’s a flavor powerhouse that can be used for many things, culinarily speaking.
If I know I will have it for a long time, I will strain it will to remove any solids (this reduces the chance of mold forming). It can be stored in the fridge or at room temperature, in a tightly sealed container. I keep a gallon jug of pickle brine on my shelf. It may build up kahm yeast on the surface, but that is harmless and I don’t worry about it. (Learn the difference between mold and yeast!)
1. Cook with it
If I am making a dip or a soup, I will often scrimp up every flavorful liquid I can find in my fridge. Sauerkraut or pickle brine makes a great addition to season and flavor any soup. Note that, when cooking anything above about 140°F/60°C, bacteria are destroyed. But flavors and organic acids remain, so no need to feel guilty about doing in your probiotics. Just be sure to get them from another source.
2. Shoot it
Any leftover brine can be drunk straight. Note that it tends to be salty, so feel free to dilute it 1:1 with filtered water if you’re concerned about too much salt.
3. Mix it
The flavorful liquid can be mixed with liquor or even beer! A chelada (also known as a michelada) is a refreshing Mexican drink, typically made with a lighter style beer such as a lager, and some kind of salty/spicy mixer. Depending on the region in Mexico, it could be made with simply lime juice and salt, clamato juice, or tomato juice with spicy pepper, like a Bloody Mary mix (known as sangrita). So this is a probiotic spin which has the same thirst-quenching effect!
4. Shake it up (salad dressing)
If I need a flavorful liquid to infuse into a salad dressing, I will often use brine in place of vinegar. A few tablespoons emulsified into ¼ cup (60 ml) olive oil make a great simple salad dressing!
5. Backslop it (fertilize future ferments)
Many fermenters swear by backslopping, which is simply inoculating a new batch of to-be ferments with a mere tablespoon (15 ml) of brine from a previous batch. I think of backslopping as an “insurance policy” rather than a must-have. If you have some on hand, and you really enjoyed the previous batch, it’s a great way to ensure a similar batch. If you don’t have any on hand, you can still make a successful ferment without it.