We have made the move from Frontier Co-op teas to Rishi Tea & Botanicals. It had been on my mind since I first started the brewery in 2016 to find a company more focused on tea that aligned with our values as a company. Ideally, they would be organic, non-GMO (not a big hurdle in the tea world), fair or direct trade- ideally with a relationship with the tea gardens or suppliers, and lastly I wanted them to be tea people. Kombucha is first and foremost a tea so I wanted to find a company who had made tea their passion. There is far more to tea than most people know.
A friend, Niraj, who owns Leaf Tea Bar/Happy Earth Tea Company in the South Wedge district of Rochester recommended two books on tea. The first was a handbook and the second was Tea: History, Terroirs, & Variety by the tea company Camellia Sinensis. It opened a whole new world of possibilities.
Our first order of Rishi teas came in around the same time as our larger glass fermenters and we brewed up a few batches.
We are into our second round of second fermentation trials. Unfortunately but not surprisingly, the first batches were a total wash. It had been a long time since I’d brewed and never had kombucha been brewed in the new brewery space. These second batches of trials along with the new Rishi tea ferments, however, are all exhibiting stone fruit flavors, particularly peach. This isn’t the first time someone has noted a decidedly peach tone to a brew. Professor Ben Wolfe, of Wolfe Labs at Tufts University, commented on SCOBY differences in an interview with the ladies of Gastropod podcast. “By appearances they’re really different and by smell they’re very different as well. Some of them smell a lot like stone fruits, you get peaches, you get really, really sort of fruity flavors.” The full podcast episode is at the bottom of this page.
Of these new teas, the white peony tea tastes like white peach and the peach blossom tastes of ripe, summer peaches that pucker your mouth with their surprising delectableness. I love peaches. But I’ve never experienced such a dramatic flavor profile across the board. So I’ve delved into searching for the cause. Here are the possibilities:
Theory A) A yeast strain with peach characteristics, specifically one such as the yeast known in the beer world only as s-05 or US-05, has made its way into BB’s open air ferments. The peach characteristics are exhibited in beers at much lower temperatures (mid 60ºF) than our kombuchas but perhaps the warmer temperatures draw them out. There is also an isolated yeast called Peach-1 from SouthYeast Labs, affiliated with Milk the Funk that talks about a peach yeast strain. They’re doing a lot of cool harnessing of wild yeasts.
Theory B) y- Decalactone, or gamma-decalactone. (Chemical formula: C10H18O2). This chemical compound is found naturally in stone fruits and is known for it’s intense peach flavors. It’s FEMA profile is fat, fruit, lactone, and peach and is largely bioengineered to be used as a flavoring agent. According to Food Technology & Bio Technology, “Lactones are flavour compounds that can be directly obtained from fruits through chemical methods or biotechnological processes. Among lactones, γ-decalactone is the most widely produced and has a fruity peach flavour.” You can read more about “Production of γ-Decalactone by Yeast Strains under Different Conditions” here. Essentially, it’s a not-uncommon result of fermentation that can also be man-made.
Theory C) It’s all in my head except the tea named “peach blossom” brewed with peaches.
There you have them. We shall see how these brews progress and change and continue searching for answers. I do love peaches though and would be pleased if they just happen to pick up a peach aroma and yeast from the air.