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I love hot food. Hot sauce, spicy mustard and cayenne pepper are a standard in my kitchen. The flavors of the various peppers are very individual along with the intensity of the spice. One of my favorite hot sauces is tabasco. It is a fermented hot sauce which has been fermented and aged in wooden barrels.
Fermentation reduces the amount of capsaicin in the pepper which lowers the heat of the pepper. While the fermentation is active the microorganisms break down some of the capsaicin, once the fermentation slows the heat of the pepper stabilizes.
Capsaicin is the compound which makes peppers hot by attaching itself to the pain sensors in your mouth which makes the pepper seem hot. The intensity of the heat of a pepper depends on the amount of capsicum found in the pepper.
What does fermentation do to Peppers?
What happens to peppers when they are fermented depends on the method which the peppers were fermented with. Peppers are a fruit, the seeds for the plant are contained within the fruit of the plant. Even though we treat peppers as a vegetable in the kitchen when fermenting them they must be treated like the fruit they are.
Fermentation consumes the sugar found in the peppers for fuel and breaks down some of the components of the pepper, including capsaicin, which makeup the pepper’s structure. This makes them less hot, less sweet and increases their acidity.
Peppers can be used to make pickles such as these lacto fermented jalapeno pickles, made into hot sauce or even vinegar. Each of these fermentation methods use a different set of microorganisms which affect the peppers differently.
Lacto Fermented hot peppers
Lacto fermented pickles are made with the use of a salt brine which helps to keep the peppers crisp, reduces the heat of the pepper a little and increases the storage time. Any pepper can be used or you can mix them together for a different flavor.
Fermented hot sauce
When peppers are made into hot sauce the peppers are usually fermented in a salt brine and aged a longer period of time. This helps the flavors of the peppers to blend with the flavors produced during fermentation. If the peppers are stored in a wooden barrel they take on some of the flavors from the wood as well. Often once fermentation is complete the peppers are blended and mixed with vinegar or other flavor components.
Acetic Acid Bacteria Fermentation (making spicy vinegar)
Making hot pepper vinegar can be done by soaking peppers in already finished vinegar. This adds some of the flavors of the pepper into the vinegar including capsaicin which makes the vinegar hot. This isn’t really fermentation as the microbial activity in the vinegar is limited and as a result the heat of the peppers is preserved. This is because of the minimal fermentation which occurs, instead the capsaicin from the peppers leaches out into the vinegar making the vinegar hot.
Peppers which are fermented with acetic acid bacteria make for a very special vinegar. The flavor of the peppers really comes through rather than just the spicy heat effect. All peppers have a unique flavor which is sometimes hard to discern when the peppers have a high spice level. Making them into vinegar allows the flavor of the peppers to come through. Here is a recipe for this type of vinegar.
Ways to control the spice level of fermented peppers
Remove the white pith from inside the peppers
In most pepper species capsaicin is found in the white pith which surrounds the seeds. By removing the pith most of the capsaicin is removed from the pepper and the spice level of the pepper is drastically reduced.
This is why recipes remove the seeds from the pepper to reduce the spiciness of a dish. It isn’t the seeds which hold the heat but by removing the seeds the pith comes along with it.
Increase fermentation time
The amount of time the peppers are actively fermenting will determine how much the heat of the peppers will be reduced. The bacteria in the culture breaks down the capsaicin during active fermentation. Once the fermentation slows and essentially stops the amount of capsaicin stabilizes.
You can control how long and how intense the fermentation will last by controlling the amount of sugar you add. The more sugar the longer the fermentation (up to a point). Adding sugar to a fermentation will increase the available food energy for the bacteria and yeast but it will also alter the flavor and texture of the fermentation due to a longer active fermentation.
Use a mix of peppers
Just as all peppers have a unique flavor they also have a unique capsaicin content. By mixing cooler peppers with hot ones you can control the ultimate temperature of the fermented peppers.
Does fermentation break down capsaicin?
If you were to leave hot peppers in the garden year round the peppers would decompose and release their seeds for the next year’s growth. The bacteria and yeast found in the soil breaks down the capsaicin allowing the seeds to be released from the pith of the pepper. The same thing happens when you ferment peppers using the natural bacteria found on the peppers.
Fermentation breaks down some of the capsaicin found in the peppers through metabolic processes of the fermenting bacteria such as Lactobacillus sakei. The amount of breakdown is limited by the amount of sugar available and slows once the fermentation is complete.
How long should you ferment peppers for hot sauce?
There are many ways to make fermented hot sauce and the fermentation time changes with each method. Tabasco sauce is made by mixing the peppers with salt and fermenting in oak barrels for two to three years, sometimes longer, fermented jalapeno pepper pickles can be made in two to three weeks and cayenne peppers fermented in hot locations can be turned into sauce within a few days to a week depending on ambient temperatures.
If you want to reduce the heat of the peppers, ferment them for at least five days as it takes at least five days for the lactic acid bacteria population to be large enough to make a difference in the amount of capsaicin found in the peppers.
The active fermentation time of peppers will depend on the amount of sugar found in the fermentation. The more sugar in the peppers the longer and more intense the fermentation will last. Once the sugars have been depleted fermentation will slow and the sauce will begin to age rather than ferment.
Once the active fermentation has stopped the amount of capsaicin in the peppers will level out and the heat of the sauce will remain steady from then on. It is only during active fermentation that the capsaicin levels are affected.