Build your own fruit bomb

What to do (or not to do) with a handful of berries from the yard

Jostaberry soda

In its fourth year, the growing collections of the Kauffman-Rummell Library of Lesser-Known Berries keep presenting us with problems of scale.

The raspberries and blueberries in our yard are now producing multiple pounds of fruit, but the rarer berry bushes still offer up only a taste or two. With the exception of the wild strawberries, which never make it back to the kitchen, we have logged our harvest in specimen jars in the freezer: Honeyberries, goumi berries, black cap raspberries, white currants, and salal berries each get a tiny container. The red currants alone have warranted a pint. Another half-dozen berry shrubs were knocked out of 2024 production by February’s ice storm, and we’re hoping to get fruit from them in 2025.

Jostaberries (now frozen), red currants (ditto), and red raspberries (eaten) from a June haul. Also some oregano I picked for chimichurri.

Last year, when our harvest was even skimpier, I would add a few handfuls of lesser-known berries to farmers’ market fruit, baking them into one of Yossi Arefi’s Snacking Cakes. This year, I’m contemplating an end-of-season all-berry jelly, which will be more of a performance piece than a symphony of interesting flavors. Most likely, it will taste like foraged blackberries, since the neighborhood brambles have been hard to stay away from.

Our most prolific lesser-known berry has been our jostaberry (pronounced yo-stah-berry) bush, which exploded in size two years ago but finally yielded useable amounts of fruit this summer. From mid-June through mid-July, we headed out in the yard every few days to pick the ripest fruits, adding them to a large container we kept in our freezer. All in all, I think we gathered 8 cups of jostaberries this year.

Jostaberries and extremely vigorous jostaberry bush

And yet jostaberries, which are a cross between black currants and gooseberries, are a shade too tart for most uses, with tiny beards that must be painstakingly removed before we bake them or add them to a fruit salad. To avoid the latter step, I grew my own ginger bug so I could make fermented jostaberry soda.

There are scads of recipes for ginger bugs online – here are three – but the five-day process is relatively simple: Add some grated (unpeeled) ginger, sugar, and water to a jar covered in a cloth, and let it sit. The next day, do the same. In fact, repeat this step for five days in a row. By the end, the ginger bug will be fizzy and ready for inoculating fruit sodas with. (You keep a ginger bug going by feeding it regularly with the same ingredients, much like a sourdough starter.)

There are many ways to make a ginger bug, but the only must is to use organic ginger, whose skins harbor more beneficial microbes. I started my bug with cheap ginger from Hong Phat and H Mart, but my bug only sprung to life when I switched to organic ginger from New Seasons (Portland’s own Whole Foods).

Ginger bug, looking innocent

My first attempt at a jostaberry-ginger soda was such a success at a dinner party – a little tart, with an ecumenical hey-its-a-berry! flavor – that I have spent the past few months playing around with other neighborhood berries. My goal was to develop a formula that yielded enough soda to fill a one-liter bottle. After jostaberries, my favorite flavor so far has been half mulberry (which a friend picked for me), half Himalayan blackberry (which I gathered in the dog park). Here is the formula that seems to work for me, with many caveats:

1½ cups of some random berry

4 cups filtered water

¼ c. white sugar

1 thumb’s worth of ginger, grated

Juice of 1 lime or lemon

½ cup strained ginger bug liquid

Instructions: In a large pot, combine all the ingredients except the ginger bug. Bring the mixture to a low boil, then reduce the heat and simmer for 10-15 minutes. Strain out the solids and let the liquid cool all the way down to room temperature. (THIS IS IMPORTANT.) Once cool, add the ginger bug, then decant into a sterilized swingtop bottle. Leave the bottle on the counter, uncapped, for the first day – simply cover the top with cheesecloth or a scrap of cloth, held in place by a rubber band. Then cap the bottle and let it continue to ferment, burping it over the sink every SIX TO EIGHT HOURS, until it starts getting fizzy. IMMEDIATELY put it in the fridge, then continue to burp it OUTSIDE ONCE OR TWICE A DAY.

If you just read those instructions and were like, why is he trying to bring back early-2010s capitalization? This is to spare you the consequences of underestimating the power of your ginger bug.

Two weeks ago, I decided I needed to give the yeasts in a batch of mulberry soda a running start. So I added the ginger bug to the berry juice while it was still a little warm, let the soda sit out on the counter uncovered for a few days, then bottled it up and let the carbonation build for a while. Two days, maybe? Right before going to bed one night, I thought: Maybe I should release a little pressure. So I held the bottle over the sink and flipped open the cap.

There was a thunderclap, or perhaps a gunshot, and then I felt sticky, yeasty mulberry soda rain down on my head. The entire liter of soda had instantly vaporized. Now it coated half of the ceiling plus every wall and cupboard in our 200-square-foot kitchen, which we had just remodeled in February.

I spent the next hour wiping down every surface. The next morning, my husband did it all over again. There are still faint pink streaks on two of our new white walls. The tablespoon of soda I was able to salvage from the bottom of the fruit bomb I had weaponized tasted like overripe yeast slurry.

Mulberry-blackberry soda, tasting like redemption. Not pictured: flagstones below coated in berry foam.

For you, the lesson here may be: hard nope. In my case, the lesson has been to bring the bottle out to the back yard every 8 hours and open it up outside. Random-berry-ginger soda is delicious over ice. A splash of rum would not be the worst thing to add, if you were making backyard barbecue cocktails. Soda is a fine way to use up a pint of berries. We just need to purchase a pint of paint as well.