What defines a Gueuze compared to a straight Lambic?

A Gueuze is distinctively defined as a blend of different ages of Lambic. This type of beer is created by combining young Lambic (usually around one year old) with older Lambics (typically two to three years old). This blending process allows for a complex flavor profile where the fruity and sour characteristics of the younger Lambic mix harmoniously with the more developed, deeper flavors of the older Lambic.

The fermentation process continues in the bottle after blending, which contributes to the carbonation and complexity of flavors. The aging of the different Lambics also means that the sourness and funkiness can be integrated and refined, resulting in a balanced and effervescent drink that is a hallmark of Gueuze.

In contrast, other brewing styles or variations of Lambics may not involve this blending process. This characteristic of combining various ages to achieve a desired taste profile is what sets Gueuze apart from a straight Lambic, which is typically a single, unblended batch.