Collagen
Collagen is the tough protein in meat's connective tissue. Slow, moist cooking turns it into gelatin, which makes braised meat tender and stock set.
Also called Connective tissue.
Collagen is the main protein in connective tissue: the tendons, skin and sheets of tissue that hold muscle together. In cuts from hard-working muscles, such as chuck, shank, brisket, short ribs and pork shoulder, there is a lot of it. Raw, collagen is tough and chewy. Cooked slowly with moisture, it melts into gelatin, which makes meat tender and sauces rich.
How to tell it is done
The meat pulls apart easily with a fork, the connective tissue looks clear and soft, and the cooking liquid feels slightly sticky between your fingers.
Why it works
Collagen is made of tightly wound strands. Around 60 to 70°C (140 to 160°F), they shrink and squeeze out juice, which is why a stew can taste tougher halfway through cooking. If you keep the meat hot and moist for longer, the strands slowly unwind and dissolve into gelatin. This happens faster at higher temperatures, so it takes about 2 to 4 hours at a simmer or 30 to 60 minutes in a pressure cooker.
The gelatin holds water, coats the meat fibers, and gives the sauce a sticky, glossy feel. When cold, a collagen-rich stock sets to a jelly.
How to use it
Choose your cooking method by how much collagen a cut has:
- Low in collagen (tenderloin, sirloin, chicken breast, fish): cook quickly to a precise doneness. Long cooking only dries them out.
- High in collagen (shoulder, shank, oxtail, cheeks, thighs): braise, stew, slow-cook or smoke them for hours until fork-tender.
For stock with good body, use bones with lots of connective tissue: chicken wings, feet and backs, veal knuckles, pork trotters or oxtail.
Common mistakes
- Pulling a braise too early, when the meat is tough because the collagen has shrunk but not yet melted.
- Boiling it hard. Strong heat dries out the muscle fibers before the collagen melts.
- Grilling a collagen-rich cut quickly like a steak, which leaves it chewy.
Related terms
- BraiseBraising browns meat, then cooks it slowly, covered, in a small amount of liquid until tough cuts turn tender and the liquid becomes a rich sauce.
- StockStock is an unsalted liquid made by simmering bones, vegetables and aromatics in water for hours. It is the base of soups, sauces, gravy and risotto.
- GelatinGelatin is a setting agent made from animal collagen, sold as sheets or powder. How to bloom it, dissolve it and get a smooth set every time.
- Slow-cookSlow-cooking simmers food for hours at a low, steady heat, usually in an electric slow cooker or low oven, until tough meat and dried beans turn tender.
- Fork-tenderFork-tender means cooked until a fork slides in and twists with almost no resistance. It is how you know braised meat and root vegetables are ready.
- Pressure-cookPressure-cooking cooks food in a sealed pot where trapped steam raises the boiling point to about 120°C (250°F), cutting cooking times by half or more.