A big roast is the very image of a holiday dinner centerpiece. But lately you’ve probably been finding that the reality doesn’t measure up. Too often that roast, so monumental in appearance, is nothing but a giant disappointment. What should be glorious and juicy turns out to be only tough and dry.
The fault isn’t with the cook, but the cooked. Beef and pork are now raised to have much less fat than before and that can mean a disappointing dinner. Fortunately, it’s a problem that is pretty easily solved by careful preparation, though it may take some retraining on your part.
To unravel this particular puzzle, we searched through hundreds of pages of scientific reports and then cooked about a dozen roasts. We roasted pork and we roasted beef. We cooked them to medium temperatures and rarer. We used ovens that were blazing and hot, or gentle and slow, and some in between -- starting high and finishing low.
What we found surprised us. Looking at the sliced roasts side by side, the differences were astonishing. You might never have guessed that the only thing different about their preparation was the oven temperature. And the secret to the most successful -- a moist, delicious holiday roast -- was a low temperature, for the finished roast and for the oven in which it’s cooked.
Don’t panic, we’re not talking about serving Uncle Bert bloody rare roast beef. When cooked at the lower oven temperature for a slightly longer time, a roast cooked to 125 degrees (normally quite rare) came out looking more like a conservative medium-rare. The meat was firm and definitely cooked through, but still juicy and flavorful.
Meat cooked in a hot oven, on the other hand, was still slightly raw in the center -- even though it had been cooked to the exact same temperature.
To understand how this works, you need to know a little bit about meat and heat. Roasts come from tender cuts of meat -- the muscles that didn’t get much exercise. Because they have less connective tissue than other cuts, they can be cooked rarer and in an oven instead of a covered pot -- it’s the stringy sinewy cuts that need the long moist cooking of a stew or braise.
Dry cooking -- roasting, grilling and sauteing -- won’t make meat more tender, but it does have one distinct advantage over moist. It can brown. The chemical reactions that cause browning in meat don’t begin to get going until the temperature on the surface reaches about 300 degrees. Since anything cooked with liquid present will never get hotter than the boiling point -- 212 degrees -- braised meat will never brown. That’s why you saute stew meat before you add any liquid. It’s also why you should be sure to pat roasts completely dry before putting them in the oven.
It may sound redundant, but with these dry forms of cooking, dryness is always a problem. But it isn’t dry air that causes the loss of juiciness, but the effects of the heat. When meat roasts, the protein strands contract and squeeze out the moisture they hold (as we’ll see, as much as 25%).
When there is fat in the meat -- either on the outside of the cut or the fine marbling within the muscle -- this isn’t such a problem. The fat renders, too, and that makes them seem juicy even if there is less actual moisture in the meat.
And therein lies the rub. Responding to what they perceive as the consumers’ demands, the meat industry has been working overtime for the last 20 years to reduce the amount of fat in their products. The percentage of fat in the average piece of pork has been cut by a third since the early 1980s. The percentage of fat in beef fell 27% from the early ‘80s to 1990 and, according to a beef industry spokesman, is “probably well below that now.” In fact, some luxury cuts such as sirloin and tenderloin now meet government standards as “lean,” meaning they are low in fat and cholesterol.
This has been done with the intention of making all of us meat eaters leaner as well, and someday it may succeed in that. But a more immediate result has been to reduce the margin of error in roasting. Today if you overcook meat even a little bit, your guests will know it immediately.
We found the key to our roasting puzzle in a scientific paper titled “Effect of Temperature and Method of Cookery on the Retention of Intramuscular Lipid in Beef and Pork” (now, doesn’t that make you hungry?). Among the findings was that “higher internal temperature significantly increased shrinkage.” What’s more, for beef, the leaner cuts lost more weight than the well-marbled ones cooked to the same temperature.
In other words, to keep this new lean meat moist and juicy, you really need to cook it to a lower internal temperature -- rarer -- than you probably did before.
Instead of cooking beef to 145 degrees (on the medium side of medium-rare), we found that removing it from the oven at 125, then being sure to let it rest and rise to 135 yielded beef that was still firm but was far moister. For pork, use 145 degrees instead of 160 (or even, shudder, the previous USDA recommendation of 180!).
Left unanswered was the question of at what temperature you cook it.
The great debate
Students of the art of roasting are well familiar with the debate over high-versus-low-heat roasting. It really hit the big-time in 1995 when Barbara Kafka published her book “Roasting,” advocating “hot ovens, short roasting times and rare meat.” In this case, “hot” means 500 degrees (an industrial strength kitchen exhaust fan is presumed). The advantage of high-heat roasting is a really great crust as well as, presumably, moister meat due to shorter cooking time.
The opposing camp is less focused on a single personality, but its prime spokesman is probably Christopher Kimball of Cook’s Illustrated magazine. Low Heaters argue that a slower oven results in meat that is moister and more tender. In an article last year, Cook’s advocated cooking roast beef at 250 degrees. Of course, that required first searing it in a skillet on top of the stove to get any kind of crust at all.
Some cooks refuse to choose. They try to straddle the middle, starting the meat at a high temperature and then turning it down after a period of time ranging from 15 to 30 minutes.
To get to the bottom of this, we took three beef and three pork loins of roughly the same sizes and roasted them -- one each at moderately high heat (450 degrees), one each at moderately low heat (300 degrees) and one each straddling the fence (450 degrees turned down to 300 after 15 minutes).
When the roasts were done, we removed them from the oven and set them aside for 10 to 15 minutes to rest. This is standard practice for roasting, though it is often overlooked in the cook’s rush to get dinner on the table. It is important because it allows the roast to finish cooking with the residual heat retained in the meat. The internal temperature will increase from 5 to 15 degrees during the rest, depending on the size of the cut (smaller cuts retain less heat). Equally important, it allows the meat’s juices, which have been driven to the center by the heat of cooking, to redistribute evenly through the roast.
We cooked the beef to an internal temperature of 125 degrees. After a 10-minute rest, it was at 135, on the rare side of medium-rare -- definitely moist and reddish pink, but the muscle fibers were set, not raw.
The pork we cooked to an internal temperature of 145 degrees (rising to 155 after the rest). This is somewhat lower than the current USDA standard of 160 degrees, but well above the minimum for safety. Pork needs to be held at 140 degrees for less than a minute to eliminate any threat of trichinosis.
Because moisture loss is such a problem with the new leaner pork, many experts call for even lower internal temperatures. Specialty meat purveyor Niman Ranch, for example, recommends an internal temperature of 140 degrees rising to 150 for its pork. At that temperature, pork is definitely pink and moist, but some find the flavor a bit raw and metallic. At 145 degrees, pork is still moist and faintly pink, but the flavor is rounder and fuller.
The true test
What we found in our roasts was that high temperature roasting does develop a marginally better crust, but at a cost. The slight improvement in the crust is more than offset by a distinct toughening of the meat. The roasts cooked at 450 degrees were definitely chewy and a little dry in the outside portions and were still quite rare in the center. Except for the browning in the crust, the flavor was a little weak as well.
The meats cooked at low heat were more tender than their cohorts and moister as well. And, except for the very outer crust, the meat had better flavor -- it was fuller and meatier. While the exterior lacked some of the crust of the high-heat roasts, it didn’t seem enough to tip the balance.
The roasts that were cooked first at high heat then at low were right in the middle. The crusting wasn’t as good as the high-temperature roasts and they weren’t as tender as the low.
The differences among cooking methods were particularly profound with beef. Not only was the high-heat loin not as good; there was less of it. The high-heat loin weighed 25% less after roasting, compared with a 15% shrinkage for both low-heat and high-low.
Perhaps with fattier cuts, the high-heat equation might have balanced differently. One thing that was obvious was that there was hardly any exterior fat on any of the roasts we bought (the beef was graded Choice, not Prime). This, too, is part of the lean meat campaign -- an industry spokesman says exterior trim on beef cuts has shrunk from a solid inch of fat to less than one-eighth of an inch. This is not enough to develop a crust and it certainly won’t render enough fat to lubricate the hardening protein strands.
This is not to say that high-heat roasting does not work. It is still the best way to cook unstuffed poultry, where the skin provides a fatty cover that crisps and crusts well. Birds also have a thermodynamic advantage in that they are hollow. This provides a tunnel for the hot oven air to circulate through and means a far smaller surface-to-volume ratio. Because of this, birds cook fast enough that at 450 or even 500 degrees overcooking and toughening aren’t a problem.
In other words, if pigs and cows were built more like chickens and ducks, high-heat roasting might still work. Until they are, low and slow is the way to go.