Salt does more than just change the flavor of food—it can also change the texture (and the juiciness) of cooked meat.
Place parsley, cilantro, garlic, salt, and pepper flakes (if using) in food processor. Lock lid into place. Hold down pulse button for 1 second, then release. Repeat until all ingredients are roughly chopped, about five 1-second pulses. Remove lid and use rubber spatula to scrape down sides of bowl.
Add oil and vinegar to processor bowl. Lock lid back into place and pulse until mixture is evenly combined, about 5 pulses. Remove lid and carefully remove processor blade (ask an adult for help). Transfer sauce to small bowl. Set aside. (Chimichurri sauce can be refrigerated in airtight container for 2 days.)
Line large plate with paper towels. Remove chicken from brine and place on paper towel–lined plate. Discard brine. Use more paper towels to pat chicken dry. Sprinkle pepper evenly over all 4 chicken breasts. Wash your hands.
In 12-inch nonstick skillet, heat oil over medium heat for 1 minute (oil should be hot but not smoking). Use tongs to carefully place chicken breasts in skillet. Cook until browned on first side, 6 to 8 minutes.
In the Young Chefs’ Club lab, we did a blindfolded taste test of unbrined chicken breasts versus brined chicken breasts. Our tasters agreed that the brined chicken was juicier and more flavorful than the unbrined chicken. Read on to learn about the two ways that salt transforms chicken:
1. Salt adds seasoning
Tiny molecules and ions (such as the salt dissolved in the brine) naturally move from places where there are a lot of them to places where there are fewer of them. This is called diffusion (“di‑FEW‑shun”). The brine contains more salt than the chicken. As the chicken sits in the brine, some salt moves from the brine into the chicken. This makes the chicken taste saltier and more seasoned.
2. Salt makes meat juicy
Water moves from the brine, where there’s a lot of it, to the inside of the chicken, where there’s less of it. This process is called osmosis (“oz-MOE-sis”), and it makes brined meat juicier than unbrined meat. But water alone doesn’t make meat juicy—salt helps, too. When salt in the brine travels into the chicken, it changes the shape of the proteins in the meat. This helps the chicken hold on to its water, even after cooking, and makes the meat more tender.