What is a defining feature of lagers compared to ales?

Lagers are defined primarily by their fermentation process, specifically the temperatures at which they are fermented. Unlike ales, which are typically fermented at warmer temperatures, lagers undergo fermentation at cooler temperatures. This cooler fermentation environment, usually between 45°F and 55°F, allows for a more gradual and controlled fermentation, producing a cleaner and crisper flavor profile that is characteristic of lagers. The yeast used in lagers, such as Saccharomyces pastorianus, thrives in these cooler conditions and contributes to a smooth finish with fewer fruity esters compared to ales, which ferment at higher temperatures and can have more pronounced fruity and spicy flavors.

The other options may describe characteristics that can be true for certain styles or types of beer but do not define lagers as a category. For example, lagers are not necessarily higher in alcohol content than ales, do not typically use wild yeast strains (which are more common in some ales and sour beers), and can come in various colors, including pale and light varieties. This distinction in fermentation temperature is the key factor that sets lagers apart from ales.