Barista Magazine

APR-MAY 2018

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strict scientifi c experiment; rather, it was just "a fun test designed to explore a possible hypothesis." In the end of the post, he concludes that the yeast is "a subtle contributor to differences in coffee aromatics. I think it does make a difference, but a small one, in overall coffee fl avor." And that was that. Fast-forward a few years: Aida is approached by a company called Scott Laboratories that has been hard at work assessing—in hopes to distrib- ute—strains of yeast specifi cally selected for coffee fermentation. These yeasts are being developed not just in hopes that they positively affect the fl avor of coffee, but perhaps to also ensure effi cient and dependable demucilagination, which would lower the inherent processing risks of defects. Scott Labs CEO and resident fermentation brainiac Zack Scott explains to Aida that there's a science to it, that Scott Labs—which has long been established as the primary yeast monger for the United States' wine industry—has something big to share. In con- junction with microbiologists at Lallemand, which is a global leader in the development, production, and marketing of yeast, bacteria, and specialty ingredients, Zack is trying to fi nd producers willing to try the three strains on offer: Oro, Intenso, and Cima. As you might expect, Aida can't sign on to the trial fast enough. Seeing the vast potential of coffee-specifi c yeasts, Lallemand created the LalCafé range as a collection of coffee-specifi c strains. In 2010, Zack's company began supplying dry yeast to customers in El Salvador, but it wasn't until 2012 that Zack and his team started to understand coffee pro- cessing when he was invited to work with Rogers Family Coffee in Panama. Since then, Scott Labs and Lallemand have trialed more than 40 strains in 15 countries with the objective of characterizing the strains' sensory impact on different coffee varieties and developing best practices for application. All of the LalCafé yeasts (except one) are part of the sac- charomyces cerevisiae species of yeast—commonly known as the beer yeast and similar to the yeasts Peter brought to Aida in 2011. Scott Labs and Lallemand continue to work on other species of yeast and bacteria, but Zack says they feel confi dent that the current family of yeast will be the preferred range for coffee application. In fact, Lallemand microbiologists selected 15 spe- cifi c yeasts that could be used in coffee fermenta- tion based on the results of extensive phenotyping studies. Out of those 15, 10 were selected for the fi rst pilot program and fi eld trials in coffee, and from those, three strains christened Oro, Intenso, and Cima were the most successful in the various benefi ts they brought to the coffee. These three have been commercialized, while there are still a number of others strains in commercial trials. As a comparison, Scott Labs offers no fewer than 70 strains for wine because each strain has unique properties which pair with each wine's sensory A Conversation with Coffee-Fermentation Designer Lucia Solis Barista Magazine: How could yeast inoculation in coffee fermentation change the specialty sector of coffee? Lucia Solis: Inoculation is just one tool in a producer's toolkit, but when used well it can be an effective one. Controlled fermentation through inoculation can add cup complexity; reduce cup defects; increase the shelf life of green coffee; create consistency batch-to-batch and day-to-day; reduce water usage by effectively demucilaging; and offer labor predictability. At the end of the day, if producers are empowered with tools to make intentional choices, the entire industry benefi ts—not just the specialty sector, which is a small part of coffee production worldwide. And the reality is that many specialty producers also produce commercial coffee. BMag: Could we consider yeast inoculation a solution in terms of raising quality of coffee that is lower grown, or Robusta, or both? LS: I don't think there is a hard limit to how to think about inoculation of yeast and bacteria. There is a place, for example, for controlled fermentation in coffee that is already very high quality by creating consistent profi les and giving producers choice. Using microbes may not increase an already high cup score, but it can provide a different fl avor profi le and open a different market. The possibilities are endless—I've designed processes for producers that offer the consistency, effi ciency and acidity offered by "washed" coffees, but with the fruit, sweetness and structure of a "dry process" coffee, allowing the producer to consistently hit a fl avor profi le associated with "dry process" in the reduced time frame of a "washed" coffee without defects. In most cases, inoculation alone is not a magic bullet. For coffee that is lower quality or below specialty, microbes are less of a "solution" as much as a piece in a larger system. Robusta has a high potential to benefi t from controlled fermentation because it is starting from a lower baseline. I have worked with Robusta and lower-grown coffees, such as those in many parts of Brazil, and increased the complexity and overall quality through the use of advanced pro- cessing techniques, including controlling fermentation via inoculation. BMag: What risks are producers taking if they decide to try fermenting with yeast? LS: This question highlights the anxiety surrounding inoculated fermenta- tions, which is a phenomenon we saw in the wine industry a century ago. There was initial hesitation but by the 1980s, inoculation with selected microbes was embraced and became the standard. By removing the risks of uncontrolled fer- mentation, the quality of wines increased and the expression of fl avors became more diverse, allowing winemakers to express their wines in an intentional way, not one left up to chance or nature. Because of controlled fermentation, we can make wine in climates where previously it would not have been possible, unlocking a wealth of new fl avors. Chances are, even a $10 bottle of wine you buy today is better than most wine you'd encounter a century ago thanks to techniques such as controlled fermentation and improved hygiene. Yet the coffee industry still relies on methods that are over a century old. Contrary to what many may think, controlling the fermentation with selected microbes is a less risky option. Letting the changing climate dictate the condi- tions of fermentation leaves coffee producers with, at best, inconsistent batches and, at worst, spoilage and loss of product. About Lucia: After earning a degree in viticulture and enology from UC Davis, Lucia trained as a winemaker in California's Napa Valley, before she was turned on to coffee. Using the principles of microbiology, Lucia has built a career as a fermentation and coffee-processing specialist, and works with coffee producers throughout Latin America. 86 barista magazine

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