In the Netherlands it's called water and kefir. Good stuff indeed, especially during summer and basically free at the cost tapwater. No plastic packaging either! Those hipster might actually be onto something ;)
I nearly poisoned myself making kombucha at home, despite careful sanitizing and careful monitoring of pH and temperature. As a result I'm really not fond of casual recommendations to brew kombucha. Seems easy to mess up.
I ferment a lot, and know of only a few dangers: some rare fruits or veggies can produce toxins when fermenting, but non that I can easily buy in a European market. Spices and some herbs can be dangerous too, but the quantities needed for toxin levels that pose a danger, are insane.
Fungi are more dangerous. If something starts growing hair, it's out.
Dairy fermentation is more dangerous ¹, and quite hard, so I avoid that.
Alcohol is obviously a toxin too, and rather common in fermentation ;)
In nearly all cases, I'll trust one of the best fine tuned measurement devices to protect humans from toxins: my taste and nose.
(Q: how do you know the milk is beyond it's expiry date? A: Smell it! Far more reliable than a date printed on some package)
Edit: another thing to be careful with, are kernels, pits, seeds and peels. Peels can often contain lots of sprayed on chemicals that will probably kill your fermenting bacteria. Pits and kernels can contain insane amounts of toxins that we usually won't eat because they are enclosed. But crushing/long fermenting might release them
> Alcohol is obviously a toxin too, and rather common in fermentation ;)
Also watch out for methanol. Fruit pectin gets fermented into methanol so using pectase is recommended to break it down, especially if one ferments citrus juice.
America's Test Kitchen had a very recent video on Kombucha, and in one portion[1], after showing the viewers the recipe and tools they used, show us how they gave their colleagues the exact same setup but ended up with varied results.
If people whose day job IS testing food recipes, all end up with different results from the master recipe made by their colleague, then it indicates certain external factors need to be controlled to ensure consistency.
The factor they narrowed down to, was consistency of temperature, and the solution they offered was to suggest a temperature-controlled box to ensure best results.
By poisoned I mean food poisoning. Not sure what happened in the batch I made but drinking the brew gave me cold sweats and fever for two days and I emptied my bowels multiple times. So I stopped there. I still love the flavor, and I love most fermented food.
I would bet money it was something else. Fermentation usually does a good job of keeping bad fungi out. If you were careful with sanitation, it was something else like bad leftovers or something. Also, food poisoning usually takes > 24-48 hours to kick in. So if you drank it and got sick that day, it was something you ate the day or two before.
"If you were careful with sanitation" is probably the important caveat. But have to keep in mind the potential danger when mess up making food. It is possible that kombucha is easier to mess up than most fermented food or cooking in general. I know beer making is very forgiving of sanitation, and isn't dangerous if mess up.
The speed of food poisoning can be hours for some pathogens. It depends on the pathogen and the amount, and if the body detects the bad food and expels it quickly.
Oh okay got it, thanks! I also get that quite a few times, but I'm certain it's more food-related, as on those days I didn't drink the booch. But now I know what to look out for, thanks!
