Roselare is another great blend of yeasts and bacteria from Wyeast, designed to produce excellent sour beers, from fruit lambics and Gueuze to Flanders browns and red. The full gamut of yeast and bugs have been included in this blend: a Belgian ale strain, pediococcus, lactobacillus, flor sherry and two Brettanomyces strains. These all contribute their unique flavor and aroma to the beers in which they are utilized, creating uniqueness and depth of character. A sour pie cherry note is often associated with Roselare, and is very useful in the creation of representative Flanders beers. This blend does well if allowed to come into its own over a period of at least 18 months. Like the Belgian lambic blend by Wyeast, Roselare will change character over time if propagated due to genetic drift, and ferments beers extremely dry, especially with proper time and conditioning.
| Brand | Wyeast |
| Beer Styles | Flanders Brown Ale/Oud Bruin |
| Alcohol Tolerance | 11% ABV |
| Attenuation | 80% |
| Flocculation | Variable |
| Cell Count | 100 Billion |
| Temperature Range | 65-85 F |