Until the late 1800s, people assumed that the right combination of wild yeasts for lambic only existed in the Senne Valley. Shortly after the turn of the 20th century, it was discovered that these yeasts already existed elsewhere in the world. In 1904, Danish brewing scientist Niels Kjelte Claussen found the yeast Brettanomyces in English beer. He presented his findings to the British Beer & Pub Association and later published them in the Journal of the Institute of Brewing. Because he found these yeasts in British beers, he chose the name “brittanomyces” (the Greek word for “British fungus”). However, a typesetter’s error changed this to “brettanomyces,” with an e. <ref name=“GeuzeKriek”>Jef Van den Steen, [[Books#Geuze & Kriek: The Secret of Lambic Beer|Geuze & Kriek: The Secret of Lambic Beer]], 2012</ref>
While individual microorganisms are not unique to the Senne Valley, the specific combinations of these organisms are terrior specific. For example, in 1993, Frank Boon was said to have discovered 86 unique strains that he believed played a significant role in the fermentation at [[Brouwerij_Boon|Boon]]. <ref name=lambic.digest-9312>Lambic Digest, December 2, 1993, [https://192.185.42.233/lambic_digest/1993/9312.txt]</ref>.
If the yeasts for lambic are not geographically limited to the Senne Valley, is it theoretically possible for brewers, with more developed and scientifically-driven techniques, to replicate the ratios and quantities of the various strains of Brettanomyces and other microorganisms outside of Belgium? Possibly, but it would require discipline and a strong traditional focus without significant experimentation. However, there are more issues that come into play.