Reader Nate asks:
Why do sweet cream butter and cultured butter seem to have different fat content? Aren’t they’re using the same technique or is there some scientific explantion for this?
I like that question, Nate! The answer is that it’s mostly an aesthetic, but there are some functional reason for the difference, at least in the pastry world. In general European butters are about 2% higher in fat that American butters. The funny thing is that here in the states European “style” butters often have 7% or 8% more fat than typical American butters. Evidently they’re cashing in on the fact that most Americans think that Continentals are in love with fat. That’s not an entirely unfounded assumption.
Functionally, if they’re made right, butters with higher fat content are firmer than those made with less. That stands to reason since the remainder is water with a small amount of protein (about 1.5%) mixed in. More water = a softer consistency.
Firm butters are preferred in the world of pastry making, especially where laminated doughs like puff pastry, croissant dough and Danish dough are concerned. Firm butter not only makes the rolling and folding process easier, it helps the pastries rise higher in the oven because there’s less moisture to weigh down the delicate layers. Indeed some “dry butters” can have as little as 1% water.
But there’s no technical reason why a cultured butter has to be higher in fat. Hope that helps, Nate!