Tasting the terroir of wine yeast innovation.

Wine is an archetypal traditional fermented beverage with strong territorial and socio-cultural connotations. Its 7000 year history is patterned by a tradition of innovation. Every value-adding innovation - whether in the vineyard, winery, supply chain or marketplace - that led to the invention of a new tradition spurred progress and created a brighter future from past developments. In a way, wine traditions can be defined as remembered innovations from the distant past - inherited knowledge and wisdom that withstood the test of time. Therefore, it should not be assumed a priori that tradition and innovation are polar opposites. The relations between the forces driven by the anchors of tradition and the wings of innovation do not necessarily involve displacement, conflict or exclusiveness. Innovation can strengthen wine tradition, and the reinvention of a tradition-bound practice, approach or concept can foster innovation. In cases where a paradigm-shifting innovation disrupts a tradition, the process of such an innovation transitioning into a radically new tradition can become protracted while proponents of divergent opinions duke it out. Sometimes these conflicting opinions are based on fact, and sometimes not. The imperfections of such a debate between the 'ancients' and the 'moderns' can, from time to time, obscure the line between myth and reality. Therefore, finding the right balance between traditions worth keeping and innovations worth implementing can be complex. The intent here is to harness the creative tension between science fiction and science fact when innovation's first-principles challenge the status quo by re-examining the foundational principles about a core traditional concept, such as terroir. Poignant questions are raised about the importance of the terroir (biogeography) of yeasts and the value of the microbiome of grapes to wine quality. This article imagines a metaphorical terroir free from cognitive biases where diverse perspectives can converge to uncork the effervescent power of territorial yeast populations as well as 'nomadic' yeast starter cultures. At the same time, this paper also engages in mental time-travel. A future scenario is imagined, explored, tested and debated where terroir-less yeast avatars are equipped with designer genomes to safely and consistently produce, individually or in combination with region-specific wild yeasts and or other starter cultures, high-quality wine according to the preferences of consumers in a range of markets. The purpose of this review is to look beyond the horizon and to synthesize a link between what we know now and what could be. This article informs readers where to look without suggesting what they must see as a way forward. In the context of one of the world's oldest fermentation industries - steeped in a rich history of tradition and innovation - the mantra here is: respect the past, lead the present and secure the future of wine.