Lamb vs. Mutton: What’s the Difference?

Lamb is the meat of a young domestic sheep, typically around a year old. Since the animal is young, there is little fat or dense muscle, resulting in mild, moist, and tender meat. Lamb is popular premium meat in the US, Europe, and the Middle East, where chefs prepare it in various ways, including braising, grilling, and roasting. Common cuts of lamb include lamb chops, lamb shoulder, lamb loin, lamb shank, leg of lamb, rack of lamb, and ground lamb.

Some butchers also distinguish lamb from spring lamb: While lamb is meat from an older lamb (around one year), spring lamb is under three months.

Mutton is the meat of a mature adult sheep, typically between two and three years old. Producers can harvest mutton from a ewe (female) or wether (castrated male). Since the animal is older, it contains more fat and muscle, resulting in a stronger flavor and denser, tougher texture. While mutton isn’t popular in the United States, it is a ubiquitous protein in Middle Eastern and Indian cuisine, especially in mutton curries, biryanis, stews, kebabs, and slow-cooking and slow-roasting recipes.

In certain parts of the world, mutton has different meanings and names. For example, chefs in New Zealand and Australia use the term “sheep meat” to describe mutton and “hogget” or “yearling” to describe the meat of a young sheep between one and two years of age. In South Asia and the Caribbean, chefs may use “mutton” to refer to goat meat.

Mutton and lamb are two types of meat from sheep at different life cycle stages. Here are the main differences between the two types of red meat:

1. 1. Age: The key difference between mutton and lamb meats is the animal’s age. While mutton refers to the meat of an older animal (typically around three years old), lamb is the meat of a young animal (often around a year old).
2. 2. Flavor: Lamb is a younger animal, so the meat hasn’t had time to develop as much flavor—thus, it is milder with a faint, grassy flavor. Alternatively, mutton comes from an older sheep with more fat and muscles, giving it a strong, gamey flavor similar to goat, venison, or wild boar.
3. 3. Preparation: Due to its toughness, mutton tastes best when cooked slowly, which you can do using a slow cooker, slow-roaster, or meat smoker. In Kentucky, chefs sometimes use the mutton of older sheep for barbecuing. Lamb, however, is a tender cut of meat that benefits from a range of cooking methods, including roasting, grilling, and braising.
4. 4. Texture: Mutton comes from older sheep that have had more time to develop dense muscles and fat content, resulting in tough meat that can be dry or chewy. Conversely, lamb hasn’t had the time to develop much connective tissue, so the meat is often more tender and moist.

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