===Gueuze===
Gueuze/geuze is loosely defined as a blend of 1, 2, and 3 year old lambics. This ratio is very dependent on the blender's intentions, what barrels are available to choose from, and what those barrels provide in terms of flavor profile. Recently, more blenders have been experimenting with adding 4+ year old lambic to blends.
Generally speaking (and never a steadfast rule): 3 year lambic will be softer and more mellow, providing a nice base. This is used in lower proportions. A 2 year lambic will provide the most character and interesting nuances in a blend. This is used in slightly higher amounts. A 1 year lambic will provide fresh, active yeasts to further develop the blend once it is bottled, along with more fermentable sugars for bottle fermentation. This is used in the highest proportion. Again, this is not always the case. Sometimes a brewer may choose to use any age lambic in a much higher proportion than outlined here. The process is guided by tasting and smelling barrels.