We’ve had great success transforming an inexpensive beef roast into something beautifully juicy and tender by slow-roasting the meat for as long as possible: starting it in a 225-degree oven for about 2 hours and then shutting off the oven and letting it slowly climb to a final temp of 130 degrees, which takes about 30 minutes more in the fading heat.
But there’s a way to make this roast—or, in fact, any beef roast—enormously more tender and tasty: Use sous vide to bring it to about 130 degrees and let it remain at that temperature for 24 hours. The meat develops a unique buttery texture and incredible savor unlike anything you’ve ever experienced from your oven.
What Does Sous Vide Cooking Do to Meat?
There are certain chemical reactions that happen at high temperatures—the Maillard reaction gets a lot of attention—but there are also other reactions that happen at lower temperatures, over a longer period of time.
Those reactions are typically catalyzed by enzymes. These bioactive proteins, naturally present in meat, are highly sensitive to heat. As the temperature rises into the 130s, they start to degrade and become inactive. But their activity is highest just below the temperature that kills them.
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The crucial enzymes in beef, calpains and cathepsins, break down tough muscle protein and connective tissue strands into smaller snippets. The enzymes can make a difference in just a few hours, as we saw in our slow-roasted beef recipe. But the longer they work, the greater their effect, so a dramatic extension of that time also leads to a dramatic increase in tenderness. For most other cuts of beef, and other meats, 24 hours produces too much tenderness—we generally like our steaks with a bit of chew—so a few hours of sous vide cooking enhances texture just enough.
Enzymatic activity also significantly enhances flavor. The breakdown of proteins generates a host of flavorful smaller molecules, including savory glutamate and other amino acids that make the roast taste deeply meaty; these continue to accumulate as long as the enzymes are active.
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(Incidentally, these are the same reactions that happen over the course of weeks when beef is dry-aged, giving rise to its glorious intensity of flavor. But the controlled temperature of sous vide increases the enzyme activity enough to allow the same effect in hours instead.)
Other reactions take place as well: Fats release grassy, buttery volatile compounds that intensify the flavor, some of which also participate in browning reactions when the meat is seared in the final step of cooking.
And, because the beef is sealed off from the outside air, all of these flavorful new compounds stay in the roast, rather than evaporating as they do in the oven.
The next time you set out to cook a beef roast, consider cooking it sous vide through the day and night. You won’t regret it.