The Science of Brining
We find that soaking turkeys (as well as chicken and even pork chops) in a saltwater solution before cooking best protects delicate white meat. Whether we are roasting a turkey or grilling chicken parts, we have consistently found that brining keeps the meat juicier. Brining also gives delicate (and sometimes mushy) poultry a meatier, firmer consistency and seasons the meat down to the bone. (We also find that brining adds moisture to pork and shrimp and improves their texture and flavor when grilled.)
To explain these sensory perceptions, we ran some tests. We started by weighing several 11-pound turkeys after they had been brined for 12 hours and found an average weight gain of almost ¾ pound. Even more impressive, we found that brined birds weighed 6 to 8 ounces more after roasting than a same-sized bird that had not been brined.
Our taste buds were right: Brined birds are juicier.
How does brining work? Brining promotes a change in the structure of the proteins in the muscle. The salt causes protein strands to become denatured, or unwound. This is the same process that occurs when proteins are exposed to heat, acid, or alcohol. When protein strands unwind, they get tangled up with one another, forming a matrix that traps water. Salt is commonly used to give processed meats a better texture. For example, hot dogs made without salt would be limp.
In most cases, we add sugar to the brine. Sugar has little if any effect on the texture of the meat, but it does add flavor and promotes better browning of the skin.
We usually list both kosher and regular table salt in recipes that call for brining. Because of the difference in the size of the crystals, cup for cup, table salt is about twice as concentrated as kosher salt.