Kvass is a traditional fermented beverage from Russia that typically uses rye bread. But you can also make kvass from fruits and vegetables as well. In the traditional food world, you’ll frequently see beet kvass a lot, a simple tonic of beets, salt and water which is great for digestive issues. But beet kvass isn’t everyone’s cup of tea. Let’s just say it tastes, well… beety.
Fruit-based kvasses however are another story. Even kids love ’em and they make a great and healthful alternative to commercial soda.
They’re simply a combination of fruit, water and a little honey that ferments for a few days at room temperature. The fermentation process results in a perfect summer time drink that is both slightly sour, slightly sweet and slightly fizzy. There are infinite variations of fruits, herbs and spices that one could use.
Black raspberry kvass would be a GREAT place to start. And yes, you could certainly use red raspberries instead.
I used black ones because I got them for free! They’re growing all along the edges of the fields and trails where I walk my dog every day.
In the northeast, they’re fairly common throughout July. Just look along the perimeters of fields, playgrounds, parking lots, wooded areas, maybe even your backyard!
Also, don’t confuse black raspberries with blackberries. Black raspberries are smaller and when ripe, have a hollow center that easily pulls away from the vine. Blackberries when ripe, have a white core and are not hollow.
Here’s a few pics:
You’ll also have to work a little harder to pick them as they don’t produce as much fruit as red raspberries or even blackberries. It took me about an hour to get a quart’s worth on a recent hike.
But for me, that makes harvesting them all the more rewarding.
But if you’re not as gung ho as I am about picking them yourself you can probably find them at farmers markets and/or in stores though you’ll probably pay a pretty penny for them. 95% of all commercial black raspberries comes from Oregon.
OK, so let’s learn how to make black raspberry kvass!
Now, a note about the use of whey.
I’ve always used whey when I make any type of kvass. Whey acts as a starter culture and adds some good bacteria that helps to kick start the fermentation process. Recently, I read that whey is not necessary for fermented beverages the naturally occurring bacteria that exist on fruits and vegetables are adequate enough.
As always, I don’t trust anyone’s experience but my own. So I brewed two batches of black raspberry kvass, one with a quarter cup of whey and one without and compared them.
In my opinion the one with the whey was much better. It clearly tasted more effervescent. I’ll be using whey every time from here on out.
If you have a sensitivity or allergy to whey, use a vegetable starter culture instead – some pickle juice or sauerkraut juice would work fine.
As an experiment, I also transferred the batch with the whey to a soda bottle (see top image) that I’d just purchased and let it sit for an additional day. Soda bottles help to increase the carbonation and boy did it work well.
Check it out:
As you can see, the bubbling had increased dramatically. In fact, when I opened the bottled, it shot up and fizzed all over the place, including all over me and my nice shirt. This brought back memories when I was a kid when I’d a shake a soda bottle and give it to my unsuspecting younger sister to open. Can you say “karma?”
Now you don’t need soda bottles. Mason jars are perfectly fine. But if you want some extra fizz you can get soda bottles right here on Amazon.
And if you enjoy making black raspberry kvass, you’re not too far away from learning now to make your own wild fermented soda. There’s only a few minor differences. Here’s a few of my posts for making fermented soda:
Craig Fear is the creator of Fearless Eating and the author of three books, The 30-Day Heartburn Solution, Fearless Broths and Soups and The Thai Soup Secret. After years helping clients with digestive issues, Craig decided to pursue writing full-time. He intends to write many more books on broths and soups from around the world! Click here to learn more about Craig.