I’m still fairly new to fermentation. At the time of writing, I’ve been experimenting for about twelve weeks, mostly with chillies, and gradually learning what works and what doesn’t.
My first ferments were very simple chilli brines, but I quickly started experimenting by adding other ingredients depending on the type of hot sauce I wanted to make. Garlic, carrot, onion, black peppercorns and even pineapple have all made their way into my jars.
It has been a mixture of success, experimentation, and the occasional failure — which, from what I gather, is quite normal when you first start fermenting.
My Basic Chilli Fermentation Method
My current chilli fermentation method is fairly straightforward:
- 750ml glass jars
- Glass fermentation weights
- A 2% salt brine
- Whole or roughly chopped chillies with additional flavour ingredients
Everything goes into the jar; the weight keeps the ingredients submerged under the brine, and the jar is left to ferment at room temperature with a loosely fitted lid.
So far this simple method has worked very well for chilli ferments.
Early Mistakes
Like most beginners, I made a couple of mistakes early on.
Initially I used food-grade zip-lock bags filled with brine as weights. In theory this is a common suggestion and should work perfectly well. In practice, however, I found it quite difficult to get right.
The bags tend to move around, and it’s surprisingly tricky to make sure the chillies remain properly submerged. Twice the bag failed to keep everything under the brine, and mould developed, which meant the entire batch had to be discarded.
Since then I’ve switched to proper glass fermentation weights, which have made the process far more reliable.
Kahm Yeast
One recent batch developed a thin film of Kahm yeast on the surface.
This can look alarming if you’ve never seen it before, but Kahm yeast is harmless. It forms when natural yeasts find a little oxygen at the surface of the ferment.
In my case I simply skimmed it off and carried on fermenting. The finished sauce turned out perfectly good.
That said, it did make me think about whether reducing oxygen exposure might help prevent it happening in the first place.
Blending the Finished Sauce
Once the chillies have fermented, the contents of the jar are blended to make the final hot sauce.
At the blending stage I usually add the following:
- Apple cider vinegar
- A little honey
- Fresh lemon juice
- A small amount of lightly boiled carrot
The vinegar sharpens the flavour, the honey balances the heat, and the lemon juice lifts the overall taste. The extra carrot is there mainly to give the sauce a bit more body and a smoother texture without diluting the chilli flavour too much.
Once blended, the sauce is poured back into clean jars for storage.
At that point I finish each jar with a small slick of olive oil on the surface before sealing it with a loose-fitting lid. The oil forms a thin barrier on top of the sauce, which helps reduce contact with air inside the jar.
Why I’m Considering a 3% Brine
One thing I keep returning to as I refine my chilli fermentation method is salt concentration.
Up to now I’ve been using a 2% salt brine, which works well and encourages fermentation to start quite quickly.
However, many fermenters recommend experimenting with slightly higher salt levels, typically around 3%. The additional salt can make the ferment a little more stable by helping to suppress unwanted yeasts and surface growth while still allowing beneficial lactic acid bacteria to thrive.
For that reason I plan to run a few side-by-side batches using both 2% and 3% brine to see if there is any noticeable difference in flavour, fermentation behaviour, or stability.
Expanding Beyond Chillies
Most of my early chilli fermentation method experiments have focused on a single ingredient, but I’m also beginning to experiment with vegetables.
One recent attempt involved fermenting baby cucumbers (pepinos). Unfortunately this batch failed for the same reason as my early chilli attempts — the plastic bag weight didn’t keep everything properly submerged, and mould developed.
The batch had to be discarded.
I’ll try cucumbers again soon, this time using proper weights and a slightly improved setup.
Testing Airlock Lids
I’ve also ordered some inexpensive silicone airlock lids, which are designed to allow fermentation gases to escape while preventing oxygen from entering the jar.
The theory is that this may reduce the likelihood of Kahm yeast forming.
Over the next few weeks I’ll be testing these lids alongside my usual loose-lid method to see whether they make any practical difference.
Fermentation Is a Learning Process
One of the most enjoyable things about fermentation is that there is always something new to try. Every batch seems to teach you something.
Sometimes the lesson is about flavour combinations. Sometimes it’s about technique.
And occasionally it’s simply about what not to do next time.
If you’re just starting out, don’t be discouraged by the occasional failed jar. Even experienced fermenters lose the odd batch.
The important thing is to keep experimenting — and to keep refining your chilli fermentation method as you go.
Footnote:
This post is part of the Fermentation Hub. It joins Fermented Green Chilli Sauce — Verde Fresco in my growing Ferment Series, which you can explore in the Fermentation Hub — a space where I'm gathering all my experiments, notes, and lessons learned.
Keep fermenting - more live cultures, pickles, and preserves here.
Wonky photos, proper food, genuine adventures — The Flexible Chef
Coming Soon
I’ll be testing the new airlock lids over the next few weeks and will report back with a full comparison between the two approaches.
Look out for a follow-up article:
“Airlock Lids vs Loose Lids for Fermentation – My Real Results.”
Sounds delicious. Gotta say, kahm yeast is caused by oxygen getting into your fermentation. If you use a good airlock you won't see kahm yeast at all. But you do you! It looks yummy