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Why Brisket is the Toughest Tough Cut

We ran a test kitchen experiment to determine why brisket takes twice as long to turn tender as do other braising cuts.

Brisket takes about twice as long to turn tender as do other braising cuts. We’ve always thought that’s because brisket has more chewy collagen (the main component in meat’s connective tissue) than other cuts, which needs more time to convert to soft gelatin for the meat to fully tenderize. But while developing our recipe for Braised Brisket with Pomegranate, Cumin, and Cilantro (page 8), we were puzzled to see that the braising liquid was thin and runny rather than silky and unctuous, the way you’d expect liquid full of gelatin to be. Could some other dynamic be at work? We decided to compare the gelatin produced by brisket with that of chuck roast, which often produces rich, thickened braising liquid.

EXPERIMENT

We sealed multiple 100-gram portions of brisket and chuck roast in bags and cooked them using a sous vide device at 195 degrees for 8 hours; at that point, we knew that both cuts would be tender and that they would have released as much gelatin as possible. We also included samples of veal breast—the same cut as brisket but from a calf—to see if age influences collagen (and thus gelatin) content. We drained the liquid from each bag, chilled it overnight, removed the fat, and then examined the gels for firmness.

RESULTS

To our surprise, the brisket and the chuck roast produced similar amounts of gel, and both gels were loose. Meanwhile, the gel from the veal breast was significantly more firm.

EXPLANATION

Collagen is most abundant in muscles that get the most exercise. For this reason, brisket (from the breast, which supports 60 percent of the cow’s weight) is naturally higher in collagen than chuck (from the shoulder). But over time, exercise creates cross-links in collagen that transform it from a soluble form to a stronger and more insoluble form. Insoluble collagen can only weaken and soften with prolonged exposure to heat; it won’t break down into gelatin. Thus, while brisket has more collagen than chuck, the collagen in both these well-exercised cuts is mainly insoluble, so neither produces enough gelatin to create full-bodied juices. Because veal breast (young brisket) comes from a calf that hasn’t experienced much exercise, its abundant collagen is mainly soluble and breaks down readily into gelatin.

TAKEAWAY

Brisket does indeed take more time to cook than other tough cuts because of its greater amount of collagen. However, much of that collagen is insoluble, so little of it will break down into gelatin. That’s why we needed to bolster the viscosity of the thin braising liquid in our recipe with powdered gelatin.

Gel Tells All

Brisket and chuck have mainly insoluble collagen and produce watery gel (top two spoons), whereas veal breast gel is very firm (bottom spoon), indicating more soluble collagen.

Collagen, Up Close

Soluble collagen: few cross-links

Insoluble collagen: many cross-links

Collagen is a triple helix made of three protein chains that unwind during cooking to form supple gelatin. But age and exercise can create cross-links that allow collagen only to soften, not to fully unwind.

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