Why ferment?
Most hot sauce you've ever had is basically chilies blitzed with vinegar. Fermented hot sauce is a whole different animal. Nothing gets added to make it sour. The chilies do that themselves.
You leave them in salt water for a few weeks to months, and the good bacteria that already live on them slowly turn the sugar into acid. What comes out is tangier, deeper and funkier than anything you'll find on a supermarket shelf.
Pick your chilies
The chili is the star of the show. Keep it to one type, or mix a few, both totally work. Just know that the colour of your chilies is pretty much the colour of your sauce.
- Jalapeño, Fresno ●●○○○
fresh, fruity, easy going - Serrano, Cayenne ●●●○○
crisp, clean heat - Habanero, Scotch bonnet ●●●●○
tropical, floral, fruity - Ghost, Reaper ●●●●●
respect it. gloves!!
Honestly, sometimes I just grab whatever looks the freshest at the local market. You don't even need to know what it's called.
Build around it
Now you can add whatever fits the sauce you're after. Garlic and onion go into pretty much every jar I make, they give it depth. On top of that:
- Sweet & round: carrot, red bell pepper, mango, pineapple
- Fruity & jammy: blackberry, peach, cherry
- Bright & fresh: green apple, ginger, lemongrass
- Deep & earthy: smoked chipotle, turmeric, mustard seeds, bay leaf
Let the chilies be the biggest part and treat the rest like seasoning. Other than that, no rules.
Grab your gear
You really only need 3 things. That's it!
- A jar. I use 1 L jars.
- A lid with an airlock. It lets the gas out but doesn't let air (or fruit flies) in.
- A ferment weight. It keeps everything under the brine.
Want it all in one go? Grab a ferment kit. Or DIY the airlock: drill a hole in a normal lid, pop in a rubber grommet, and stick in a cheap S-airlock.
Cut it big
Gloves on!! Seriously. Chili on your fingers + rubbing your eye = bad time.
Wash everything and pull the stems off. Then cut everything in big pieces: halve the chilies, quarter the onion, thick carrot coins. Big pieces are way easier to keep submerged later. Small bits float up, and floaters are where mold starts.
Seeds can stay. But if I have some spare time I take them out too. You'll thank yourself later.
Garlic: just peel it, give it a light crush to activate it, and toss it in whole.
The salt math
I ferment in 1 L jars. The whole jar gets filled by your produce in grams + water in ml. Like 600 g + 400 ml = 1000 g. Sorry, no clue how much that is in ounces. I don't do inferior measurement systems. A regular kitchen scale will do just fine.
Now you add salt to that water, and that's your brine. It keeps the bad stuff out and pulls all the juice and flavour out of the produce later. Use unprocessed natural sea salt (no iodine, no anti-caking stuff), and go for 2–3% of the total weight.
Don't calculate it off the water only! 10 g in 400 ml sounds fine, but that's only 1% for the whole jar. Too little = mold party.
Pack it, sink it, seal it
- Stir the salt into the water till it's dissolved.
- Pack the produce in the jar. Snug, and fill it up high, all the way into the neck.
- Pour the brine over it.
- Press the weight in right at the neck, so it covers pretty much everything and nothing can sneak up the sides.
- Leave a little headroom above the brine.
- Close it with the airlock lid. Done!!
Label it with the date so you don't forget. Then room temp (18–24 °C), out of the sun.
Check once a day or so
For the first few days, check once a day. The only thing you look for: does anything float on the surface?
Cause that can and will cause mold, and then you have to toss the whole thing. Mold is our biggest enemy here. Floater? Push it back down with a clean spoon.
Bubbles, cloudy brine, colours getting duller: all normal. That means it's working!
Now let it go
If after the first 4–7 days it's all good and nothing floats, you now have to just let it go. I usually ferment at least 1 month. Watch the day counter go up as you scroll.
Real talk though: you won't be able to fully resist checking in on your baby every once in a while. That's ok! You're free to open it, smell it, even taste the brine now and then. You're excited, that's understandable.
Just don't make it a daily thing, close it back up, and make sure everything's still under the brine.
“Is this mold?!”
At some point you'll probably see a white layer on top. Not every jar gets it, but it's likely, and it's usually kahm yeast.
Kahm is a harmless wild yeast that loves the bit of air on top of your brine. Skim it the first time if you want, but it'll come back, and opening the jar every time does more harm than good. So I skim once, let it be, and skim one last time before blending.
Not sure which one you have? Watch this short video on kahm vs mold.
Check the pH
As you get close to the end of your ferment (for me that's around 2–3 months), it's time to check the pH. Bubbling calmed down, brine smells nice and sour, a chili piece tastes tangy? Good signs.
pH, super simple: it tells you how acidic something is. Lower number = more acidic. Less acidity = higher pH. Water is 7, lemon juice is around 2.
Why? Safety: below 4.6 the nasty stuff (like botulism) can't grow. And if you want it shelf stable, you want 4.0 or lower.
Cheap pH strips are totally fine for this. Wanna go fancy? Get a digital pH meter.
Not there yet? No stress. Give it another week and measure again.
Blend it
- Skim off the kahm one last time.
- Separate the produce from the brine. Keep the brine!!
- Produce goes in the blender.
- Slowly add brine until you reach the consistency you want.
Slowly! You can always add more, but you can't take it back out.
Pro tip: xanthan gum. Homemade sauce likes to separate in the bottle after a while, watery on top, pulp at the bottom. Totally normal, just give it a shake. But if you want it to stay smooth and silky, add a tiny pinch of xanthan gum (a natural thickener) while blending. About 0.1–0.3% of the sauce weight, so 0.5–1.5 g for 500 g. Go easy, too much turns your sauce gloopy.
Add fresh fruit?
This one's completely optional. Here's the thing: by now all the sugar is gone, the bacteria ate it. So even if you put a LOT of pineapple in the jar, it'll taste and smell very little like pineapple.
If you want that bright fruity taste, you can add fresh fruit during the blend. But it changes a few things:
Pasteurizing: put it in a pan and quickly bring it to about 85 °C (gentle simmer), keep it there a few minutes, then bottle it hot. Otherwise the bacteria start eating the new sugar and make gas in the closed bottle. Not fun.
It's alive!
Is it probiotic? Technically yes (if you don't pasteurize). It's full of live lactic acid bacteria, same family as yogurt or kimchi.
But let's be real, you eat hot sauce by the drop. So no, it won't do much for your health.
It's more about the fact that it's kinda cool that your hot sauce is still alive.
Bottle it
I use the classic 5 oz woozy bottles (the ones with the little dripper cap) and a small funnel.
- Sterilize bottles & caps (boiling water or a hot dishwasher).
- Pasteurized? Fill it hot, cap it, flip it upside down for a minute.
- Not pasteurized? Leave a bit of space, straight into the fridge, open it once in a while to let the gas out.
- Label it! Pepper, date, pH.
How long does it keep?
Pasteurized + pH 4.0 or lower + bottled hot = shelf stable till you open it. After that, fridge.
Not pasteurized = fridge only. Keeps for months, often over a year.
Personally I keep all mine in the fridge. After 3+ months the fermentation is pretty much "finished" and the cold slows it way down, but it still keeps developing this beautiful flavour.
My best bottles are always the ones I forgot about in the back of the fridge.
And now?
Ok, now the most important part, and the whole reason I make hot sauce in the first place…
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