In his early days of baking, Steve created a leavener with a starter inoculated with wild yeast from wine grapes.

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They used a grape press, tasted juice in various stages of fermenting and attended a "riddling" lesson, learning how to turn wine bottles to facilitate yeast removal.

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At its worst, the wine can smell a bit like that, too, if a certain yeast strain called Brettanomyces makes its way into the fermentation process.

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