Equally important is the proper mixing of fat, meat, and
seasoning. Because well-ground meat is chopped, the tiny
individual pieces of meat don’t actually get much of a
chance to rub up against one another and develop strong
protein bonds through the dissolved myosin. So, after your
meat is ground, it needs to be kneaded, precisely like a ball
of dough. The metaphor is especially apt: the purpose of
kneading dough is to build up bonds between flour proteins
to create better structure, while the purpose of blending
sausage meat is to build up bonds between meat proteins to
create better structure. That it also helps the flavorings to
become more evenly distributed is an added bonus.
The absolute easiest way to do this is in a stand mixer
using the paddle attachment, though a large metal bowl and
bare hands are much more fun. However you do it, just
make sure to work quickly. You’ll need to mix the sausage
meat for at least a minute or two, until it is sticky and tacky
instead of loose or crumbly, but if it threatens to get too
warm, throw it in the freezer for a few minutes to cool it off
—you’ve come too far to ruin your sausage now!
Flavoring
For the simplest sausages, all you need is pork shoulder and
salt. But the beauty of a sausage is that, unlike a solid piece
of meat, you can build your flavorings directly into it. And
now that you know the keys to good texture and moisture,
you are free to flavor your sausages however the heck
you’d like. You can even make them with whatever meat
you’d like, though here’s a word of warning: pork fat is the
best fat to use for sausages, even when using other meats.