Changes

Spontaneous fermentation is a complex process compared to the cultured fermentations of other beers. Several genera of both yeast and bacteria are involved in making the final product. The order in which these organisms dominate the flora allows us to divide the fermentation process into several distinct stages. We have chosen to divide the process into four distinct parts. First, colonization by enteric bacteria, which is responsible for production of acetic acid in the wort, followed by the growth of the yeasts Kloeckera and then Saccharomyces, which ferment most of the simple sugars and produce the majority of the ethanol in Lambic. During the Saccharomyces dominanace of the yeast flora, the bacterial flora switch to primarily lactic acid bacteria, which do exactly what you'd expect something with that name to do. At the end of fermentation, Brettanomyces comes to dominate the yeast flora, and the slow fermentation by these organisms is responsible for many of the odors and flavors associated with Lambic. The aging process then continues well after the beer is bottled. Geographic and seasonal variation, coupled with the "wild" nature of spontaneous fermentation in general, conspires to make Lambic a truely truly unique product.