Fizzy drinks are a little different. I like a nice sharp Reed's Ginger Beer, but I haven't seen one in a store shelf since we left the US. Making our own has helped fill the occasional craving.
Brewing our own kombucha satisfies both self sufficiency and personal health. This fermented tea hasn't been on the shelf anywhere during our travels except in the US and Australia. I'm not a fan of sweet carbonated drinks, and it's just the right amount of a little fizzy, a little sweet, but not too much of either- the perfect refreshing drink or something to settle a queasy stomach. It's also certainly a really great alternative to commercial sodas, and ascribed with a variety of health benefits. Whether you buy into those or not, the simplest of all is that it's probiotic, and that's good for your digestive system and general health.
Conventional wisdom would indicate brewing kombucha is not compatible with a cruising boat. Movement hinders fermentation. Sunlight is bad. Temperature fluctuations don't help, either. Then there's that big glass jar it sits in: breakage hazard on a moving boat!
Really, it's not so difficult, even on a leaner (as our multihull friends would say) like ours. We churns out new brew at a considerable rate. You need a "starter" (this crazy mushroomy looking thing called a scoby, which is the acronym for Symbiotic Colony of Bacteria and Yeast. Yum!). Then, you just need black tea and sugar, and a big glass jar to keep it all in. There are endless variations of tea types and flavors.
To minimize the chance for toppling the brew, I keep it low and in the center: it lives in a little nook of space just forward of the mast. If things get really boisterous, we tie it to the mast with webbing, and I can replace the permeable (cloth) top with a screw-on cap. If I really need to (like we did those last 3 days coming into PNG), I stash it with soft goods in a locker.
There's a spare scoby stashed in an old jam in our fridge, in case I kill the primary.
The only thing missing: people to share my starter with!
If you want more details about how to make kombucha, on board, there's a good illustrated summary at Kaiku Lifestyle.
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