Why Brisket Is Tough

Brisket comes from the chest area of a cow, between and just below the muscles that make up the chuck. They're used every time the animal takes a step or stands up, and like other well-used muscles they become dense and tough as the animal matures. Their muscle fibers are long and packed tightly, and they have little internal fat to "marble" and tender the beef. Instead, the brisket contains lots of tough collagen. Tender brisket comes from melting that collagen into natural gelatin, without drying out the lean muscle tissue.

Melting the Collagen

You could roast your brisket to the USDA's recommended food safe temperature of 145 degrees Fahrenheit, like any other piece of beef, but at that temperature it will still be very tough. The stringy, collagen-rich connective tissues don't begin to dissolve until they reach temperatures of 180 F or higher, and aren't fully liquefied until they reach 200 F to 205 F. You could bring the brisket to that temperature very quickly in a hot oven, but high heat doesn't work well for brisket because of its effect on the muscle tissues.

Quick and Hot vs. Low and Slow

If you've ever watched a piece of bacon shrivel and shrink on a hot griddle, you already know how meat proteins react to high temperatures. They contract and become dense and tight, toughening the muscle and squeezing out much of its moisture. These two effects are exactly the opposite of what you want with brisket, which is already dense and prone to becoming dry. Most recipes call instead for roasting a brisket at low temperatures for an extended period, melting the collagen without toughening the muscle fibers.

Roasting Your Brisket

Barbecue competitors typically cook their brisket at very low temperatures, ranging from 200 F to 250 F, for several hours. Home cooks can borrow that technique, cooking the brisket in a covered roasting pan for 4 to 6 hours until its internal temperature exceeds 200 F. Covering the pan helps limit evaporation, and keep moisture in the brisket. Many recipes add at least a small amount of liquid to the pan to create steam, which speeds cooking and inhibits evaporation. The brisket can also be immersed partially in cooking liquid and braised, which helps tenderize the tough meat. Braises can be cooked at oven temperatures of up to 350 F, because liquids limit the actual cooking temperature to the boiling point of water.