Brining Is a Trade-off
Brining a turkey by soaking it in a tub of salty water (our basic brine is a cup and a half of kosher salt per gallon of water) will definitely get you moister results—up to 20% moister, says Harold—but it comes at the expense of flavor. "You've got a nice turkey with lots of turkey flavor. When you brine it, you're basically diluting that flavor with salty tap water," says Harold. A better route may be salting the bird for a couple nights. It gets some of moisture retention qualities of brining, without diluting flavor.I assume that the basic brine recipe in the quote is not Harold's and that he would not advocate brining a turkey in a 12% brine ( approx 495g salt/4000g water). A 4- 6% brine is more like it, for example this brine recipe by Alton Brown ( approx 330g salt/ 8000 g water and stock). But I digress.
Harold hits the nail on the head when he says that brining is a trade-off that gives you a moister turkey (And any meat that you brine) at the expense of flavor. He is also right to say that when you add water to the meat you are diluting the flavor. The flavor of the turkey is "diluted" by adding water to the meat, but also it is diluted because brining "washes" flavor out of the meat. Adding water to the meat will increase the ratio of water to protein to fat, so compared to the same mass of a turkey that was not brined there will be less flavor per unit mass. However, what is also true is that as the turkey sits in the brine it loses flavor to the brine. Here's why:
Think of the turkey as a balloon filled with approximately 70% water and 30% protein and other molecules dissolved in that water. The skin of the turkey balloon allows water, other small molecules and ions to pass into it and out of it. When you put the turkey in a brine that is 95% water (a 5% brine), the water inside the turkey and in the brine will move back and forth until the concentration of water in and outside of the turkey is the same ( approx 82%) and while that is happening - specifically, while water is moving from the turkey to the brine- those water soluble proteins and other, small molecules and ions are leaving the bird along with the water.
Sure, some of those water soluble proteins (like myoglobin), move back into the turkey from the brine. But they do not all go back in, some stay in the brine. This is why brines become cloudy over time (this is especially obvious in simple clear water and salt brines.) and the other half of the reason why turkey (and all meat) loses flavor when you brine it. Those water soluble molecules that are clouding the brine have flavor that is going to be dumped.
There are far better ways to take advantage of the properties of brine and its active ingredients than drowning a turkey in a pail of salt water. A brine pump allows you to inject your brine directly into the bird with no significant loss of water soluble flavorants. It's not as easy to use as a bucket of salt water, but it's faster and gives much better results.
You can also, as Harold points out, dry rub the turkey.
I rarely brine anymore, and I almost never brine poultry unless I'm going to cook the living daylights out of it on a BBQ or in the smoker. Mostly I rub with salt sometimes salt and sugar.
Dry rubbing results in very little loss of flavor, especially if you use fine salt which, unlike coarse Kosher salt, spends very little time on the surface of the meat (because is dissolves quickly) drawing out less water and flavorful water soluble molecules. I recommend a rate of 14g salt per 1000 g meat for dry rubs. If I want to add sugar to enhance browning and moisture retention during cooking and to help keep the meat tender by inhibiting coagulation of the muscle proteins, I add half the mass of the sugar to the mix so the rub becomes 7g Sugar/14g Salt/1000g meat.
I'll anticipate objections to my suggestion to use fine salt in the dry rub by saying that, even though you will lose less moisture and flavor by using it, you may want to use coarse salt anyway, especially if you are cooking poultry with skin and you like the skin to be crisp. This is because coarse salt spends more time on the surface pulling water out of the skin than fine salt and less water in the skin, means crispier skin.
See, I told you this was going to be a nuanced discussion. ;-)
that's only if you eat a smaller serving of turkey than you would have eaten had you not brined.