Science of Meat: What Makes Meat Juicy and Tender?

Juiciness and tenderness are two very important factors when it comes to meat quality. Both factors are influenced by the cut of meat you choose and how long the meat is cooked. The more a muscle is used, the stronger, and therefore tougher, the cut of meat will be. And the longer meat is cooked, the more liquid it loses and the tougher it becomes. Factors that also influence tenderness and juiciness are: The animal's age at slaughter, the amount of fat and collagen (connective tissue) contained in particular cuts, and, to a small degree, brining.

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Collagen is a long, stiff protein that is the most prevalent protein in mammals. It's made up of three separate molecules composed of amino acid chains, twisted around each other, something like the way fibers are twisted around each other to form a rope. This structure is what makes the collagen so strong; this strength is also what makes it more difficult to break down. The more collagen there is in a piece of meat, the tougher it is to cut and to chew. Skin is mostly collagen, as are the tendons that connect muscles to bones. For cuts that are high in collagen, cooking with methods that use slow, moist heat, such as stewing or braising, are the best. Collagen is soluble in water and when it is cooked slowly with moist heat, it becomes gelatin. You can also make collagen less tough by slicing up meat into smaller pieces, which makes the fibers smaller and easier to break apart.

The amino acid chains that form collagen.

Weight-bearing muscles and muscles that are constantly used contain higher amounts of collagen than muscles that aren't used for support or aren't used as frequently. Cows and pigs have higher amounts of collagen in the legs, chest, and rump. Pork is generally more tender than beef because pigs are usually slaughtered at a younger age than cows, and so their muscles are less developed and have less collagen than do those of cows.

Fish muscles are quite different from those in mammals. Fish float in water and so don't need muscle to support their weight. Their muscle fibers are very short and are held together by connective tissue called myocammata , which is much more delicate than collagen and breaks down much more easily when cooked. The only muscles that most fish use extensively are around the tail and fins (areas that aren't eaten as often by humans), which are used for constant cruising around in the water.

Science of Meat: What Makes Meat Juicy and Tender? | Exploratorium (2024)

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