softens and melts at a specific temperature
range, butter goes through many textural
changes as you heat it, slowly softening and
becoming more and more malleable until finally,
at around 95°F, all of the fats are liquefied.
- Water makes up another 15 percent (down to 11
percent for high-end butters, up to 30 percent
for fresh-churned butters). In the cool environs
of the fridge, the water and fat in a stick of
butter commingle without any problem. But
apply some energy to the situation by heating it
in a skillet, and eventually the water converts to
steam, forming small bubbles of vapor and
causing your butter to foam. Once the foaming
has subsided, you know that all of the water has
made its escape and your butter has begun to
climb above 212°F. Since water is denser than
fat, when butter is melted in a large pot, this
layer of water (and a few dissolved proteins) will
sink to the bottom, where it will begin to bubble
if heated long enough.
- Milk proteins, mainly casein, make up the
remaining 5 percent (or so) of the butter. These
proteins are the milky white scum that floats to
the top of your butter as you melt it, and it’s
these proteins that will begin to brown and
eventually burn and smoke as you heat butter in
a hot skillet.
Because of its water and protein content, plain
