For tender meat, don’t marinate.

From E., 1 October 2010, lamb – how to make it tender?

Q: I would like to make something like lamb kabobs at home but when I try, the lamb comes out chewy. Do I need to marinate it or cook in liquid? How can I get tender lamb?

A: Thanks for your question. Since you asked, I’m going to take this opportunity to talk about marinades, because they’re misunderstood and misused.

Marinades often are touted as the remedy to tough cuts of meat – throw them in a marinade, and you’ll get tender meat, right? Not actually. Marinades “work” by exposing the meat to a tenderizing agent – usually acid but sometimes an enzyme like pineapple or papaya. The conventional wisdom is that acid breaks down fibers (as enzymes do), and that the longer you marinade, the better.

But think about it for a minute. When you make ceviche, you “cook” the fish in acid. Exposure to citrus juice or vinegar toughens the fish and turns it opaque. Rather than becoming more tender, fish marinated in acid gains some firmness – a desirable quality in ceviche. How does this work? When exposed to the acid in the marinade, the proteins strands in the fish unravel and become enmeshed. To some extent, this bonding enables the meat fibers to hold more moisture, increasing the perceived tenderness of the meat, but it also makes the meat somewhat firmer. Enzymes work differently – they slowly turn the meat to mush by digesting the proteins. Enzyme-treated meat tends to have a mushy, somewhat slimy, surface. Don’t enzymatically tenderize your meat.

Here’s another thing. Both acids and enzymes penetrate meat poorly. Seafood turns to ceviche quickly because the muscle fibers are, for the most part, very short relative to those in meat. As food science guy par excellence Harold McGee notes, both acids and enzymes penetrate the surface of meat at the rate of mere millimeters per day, and are not particularly effective tenderizers unless injected. Hervé This – French food science guy par excellence, if you didn’t know – confirms this, and notes that the effects of aging the meat during the marination period are responsible for any tenderizing effect. Several years ago, This demonstrated that, after leaving meat in a slightly salted solution or an acidic solution for about a week, the marinade had penetrated not more than 1/8 of an inch (about 3mm), and that the meat marinated in the salt solution was somewhat more tender because age had relaxed some of the muscle fibers.

The esteemed cookbook author Shirley Corriher notes that, in her experience, dairy-based marinades are more tenderizing than other acidic marinades. Indeed, yoghurt long has been used to marinate meat in Indian cuisine, and buttermilk to tenderize chicken before frying. And the milk-braised meats of classic Italian cuisine are more tender than those cooked with wine alone, or tomato.

So now you know – except for dairy, marinades are not all that useful to tenderize meat, although they do coat its surface in flavor. If you want to add some flavor and tang to the surface of your meat, go ahead and tenderize – I never leave meat in the marinade for much more than 10-15 minutes and I don’t marinate fish except for ceviche.

On to your lamb kebabs. Lamb is a baby animal and, by definition, it should be tender. The shank and neck are fairly tough, and lamb breast – the chest muscle and fat that encloses the ribcage – can be tough, but many ordinarily tough cuts like leg and shoulder are still tender in lamb. This makes the problem easy to diagnose: if your lamb is tough, you’re cooking it too long. Lamb, unless ground or braised, generally should be served medium rare – don’t serve it rare. Because most lamb is quite tender, cut into small chunks for skewering, your lamb will cook in a short time – first over high heat to brown it, and then over lower heat to bring it to an appropriate temperature inside.

Marination won’t give you tender kebabs. It will, however, add a certain flavor if that’s what you’re after. A couple of flavors work especially well with lamb – garlic, rosemary, thyme, lemon, and aromatic spices like coriander and cumin. Try a yoghurt marinade with a spice masala, or an olive oil and lemon marinade with garlic and herbs. If you want to grill vegetables as well, do so separately – it’s hard to choose vegetables that will cook in the same time as the meat. With most vegetables, you risk overcooking the meat.

Lamb skewers

1 1/2 lbs lamb leg or shoulder, trimmed of excess fat and cubed about 1.5″
salt
metal skewers (or bamboo skewers soaked in water for 30 minutes)

One of the following:

Yoghurt/masala
1 c yoghurt (I prefer whole milk, but any kind is fine)
1/2 tsp each ground cumin, coriander, turmeric, paprika, toasted briefly in a hot pan until just fragrant
1/4 tsp each ground fenugreek and black pepper
large pinch cayenne
3 cloves garlic, grated to a paste
2-inch segment ginger, grated to a paste

Provençal marinade
1/2 c olive oil
1/4 c lemon juice
6-8 branches thyme, bruised
1 branch rosemary, bruised
6 cloves garlic, smashed
a few grinds of black pepper

Greek marinade

1/2 c olive oil
1/4 c lemon juice
zest of two lemons
large handful fresh oregano, bruised
6 cloves garlic, smashed

Combine marinade ingredients of your choice, and allow to rest for about 30 minutes.

Prepare coals for grilling by heaping on one side of the grill. Season the lamb cubes. Place in the marinade, tossing to coat, for about 15 minutes (you can leave them longer but it will not significantly affect the tenderness of the meat). Remove and, if you used the yoghurt, scrape off any excess. Thread the skewers and season lightly again with salt.

Grill directly over hot coals for about 1 1/2 – 2 minutes on each side. If necessary, move over to the cooler part of the grill and cook indirectly until medium rare and tender. The total cooking time should be about 8-10 minutes, but will vary based on the heat of the coals.

You also can cook the skewers in a grill pan on the stove. If you do, start off with a really hot, well-oiled pan to get a good sear, and then reduce the heat to cook the meat through to medium rare.