I would have liked the title of this piece to be “Stop the Insanity!!!!!” but I realize that that could be construed as overstatement. I do feel pretty strongly about this topic, though. If you want the short version, here it is (all caps necessary, cuz I am a little bit of a ranter when it comes to this topic): YOU DO NOT NEED TO USE WHEY, OR ANY OTHER STARTER, TO FERMENT VEGETABLES, AND USING A STARTER COULD ACTUALLY HURT THE QUALITY OF YOUR FERMENT.
WHY NO WHEY
Those who have looked at the current science will all agree, when it comes to veggies, whey ain’t it. The bacteria that we need for vegetable fermentation live in the soil. They are already ON the vegetables when they’re harvested, so adding a starter is, well, redundant (although that’s not entirely accurate. See “Microbial Diversity” below). The proportion of lactic acid bacteria present on pre-harvested veggies is actually quite small. When the vegetables are harvested, however, some cell walls break, which frees up nutrients for the lactic acid bacteria and gives them the fuel to multiply. Give those naturally present, procreative bacteria the conditions in which to multiply, and you’ve got yourself a ferment.
WHY DO THEY WHEY
So why do some sources say that whey is necessary or desirable? Sources that says it’s necessary are just wrong. I don’t say that lightly about anything fermentation-related, ever, but it’s just true. If you ferment this way, there’s a chance that you learned to ferment through Weston A. Price or another traditional diet organization. On working, old-style farms that combine vegetable production and dairy-farming, whey fermentation of vegetables makes a little more sense. Basically in that case, it’s a way to avoid waste. Although the whey isn’t necessary, using whey can make for a speedier ferment and if you have too much of it, why not use it for something rather than toss it?* While I can get behind just about any practice that is intended to prevent waste, there are a few downsides, or potential downsides, to using whey.
THE DOWNSIDES OF USING WHEY TO FERMENT VEGETABLES
1. Slime – I don’t know the reason for this, but vegetables fermented with whey sometimes end up slimy. If I had to venture a guess, it would be that the whey, if using whey like kefir whey, contained too much yeast and the yeast was too active, which is what can sometimes happen when fermenting with sweeter vegetables. The other possibility I can think of is that fermentation simply happened too quickly with whey as a starter and the vegetables actually started to break down. Obviously neither case yields a particularly delicious ferment.
2. Microbial Diversity – One of the reasons that I personally ferment is to introduce as much good, microbial diversity into my body as possible. I’m well aware that we don’t know what every single strain of lactic acid bacteria does for us and I’m willing to wait somewhat patiently while science decodes all of that for us. In the meantime, though, I certainly don’t ferment vegetables only to end up colonizing my gut with one or two specific strains a la a certain mass-produced yogurt brands. Even with good, heirloom yogurts, you’re getting the strains native to that culture, rather than the strains native to the soil. I believe that by introducing as much, diverse bacteria into my system as possible, I’ll be supporting internal biodiversity and given all the stupid, hard work we’ve done to eradicate our microbes of all kinds, I think that’s a very good thing. To that end, I eat a broad variety of microbial rich foods. I eat misos and pickled vegetables of all kinds. I drink kombucha and eat yogurt (and of course I throw some wine and cheese in there for good measure). Sure, there’s some overlap, but eating a broad variety of ferments gives me better odds of attaining a veritable Amazonian microbiota. SO, when whey is used as a starter, the dominant bacteria become the whey bacteria, otherwise known as the bacteria that you were already getting from eating whatever thing the whey came from. Why not err on the side of lots of different kinds of microbes?
3. A Lower Quality Ferment – There is a UN-FAO food fermentation study that I originally saw cited in The Art of Fermentation. The authors make a pretty brief yet compelling case against using a starter in vegetable ferments. The case in question is sauerkraut, and the starter used is juice from a completed batch of sauerkraut, but the logic of why this is problematic seems simple to apply to other vegetable ferments and starters. The study’s authors found that a starter with higher acidity would result in a “lower quality” kraut, while a starter with a lower acidity wouldn’t have a negative impact (other than leaving the kraut with a less crispy texture), but didn’t seem to help anything either. When the possibility is neutral or negative, why bother?
WHEN TO WHEY
Perhaps you’ve seen that I do use starters for ferments sometimes. I will use a starter (whey, rejuvelac, brine from a finished ferment, water kefir, etc) to ferment in certain situations. Fruit, sodas, things that have already been cooked (certain condiments) but that is by no means my primary fermentation habit, and I never use whey (or any other starter) to ferment straight vegetables.
If you adore fermented ketchup (or maybe thats the only way you can get those good bugs into your four-year-old’s guts) or must have a probiotic, rather than a yeasty, soda by all means, go nuts with starter experimentation. Just know that when it comes to your krauts, kimchis and pickles, it’s better to save your whey for another delicious use!
*Whey is protein rich and flavorful and is great used in dressings, stocks, stews, smoothies or as baking liquid, just to name a few.