[dropcap1]Q. [/dropcap1]What brands of butter do the upper-end restaurants use? It seems to me that it tastes a lot better than the butter I buy at the store. [dropcap1]A. [/dropcap1]Most restaurants buy butter from institutional distributors who don't market the same brands at retail. However, most of the butter that comes into this market--regardless of the brand--is actually made by Land 'O' Lakes. A taste test I did of a dozen salted butters with different brands showed no detectable difference in flavor. In general, unsalted butter is better than salted butter. The salt masks flaws, and also preserves the butter. Unsalted ("sweet") butter has to be the best quality available, because it shows every problem. You can find some premium butters in the stores, particularly those with a gourmet tilt. The most widely-distributed brand is Plugra, an American-made butter that imitates French butter. The name is a respelling of "plus gras," which means "more fat." That brings up a major issue. You might think that butter is 100 percent fat. It isn't. It contains milk solids--the foam that rises to the top and the brown stuff that sinks to the bottom after being cooked for awhile. Butter also contains a great deal of water--sometimes as much as 40 percent. The European-syle butters typically contain less water, which is why they taste better.