How tight should the lid be when braising?

Question

Much of the braising guidance I've read emphasizes the importance of a tight-fitting lid. For example, in All About Braising, pp. 18-19, Molly Stevens provides instructions for sealing a braising pot with parchment paper. The goal is to reinforce the seal since "much of the success of braising depends on trapping moisture in the pot."

On the other hand, Harold McGee, in his "Guidelines for Succulent Braises and Stews," advises braising with "the pot lid ajar to allow some evaporation" (On Food and Cooking, p. 163). J. Kenji López-Alt, in his Food Lab article on Great Chile Verde Without Hatch Chiles, notes that a pot with its lid left slightly ajar "stays a good 20°F lower, keeping the meat inside at a temperature far closer to the ideal."

How do I make sense of this seemingly contradictory advice?

Answer 1

As so often in cooking and life, the answer is a solid “it depends”.

Braising means preparing food with some liquid, in a humid environment, usually after a roasting/browning step to develop roast flavors through the Maillard reaction. There’s just a few rules of thumb as to how much liquid is appropriate, and cooking methods cover a certain temperature range, both slow cooking and pressure cooking are technically braises.

When braising, you want to strike a balance between keeping the meat moist and dissolving the collagen and concentrating and mingling the flavors of meat and liquid. And all that while not boiling the pot dry .

• Sources that favor a tight seal are putting more emphasis on the „keep moist“ factor and „keeping all flavors in the pot“. (Yes, the reason that your kitchen smells so nice is due to some aromatic compounds being carried away by the evaporating steam.) They will often be on the lower end of adding liquid, so not losing anything is more important. Or if the roast is done, the cook may add an extra step to reduce the sauce if necessary.
• Keeping the lid ajar means evaporation is desired, the sauce is reduced during the braising and the lower temperature lowers the risk of overcooking the meat (-> compare slow cookers). With an open lid, it’s probably a good idea to keep an eye on the liquid level and top it up in case it gets too low.

Both approaches are justified, and I wouldn’t overthink it. Do what works best for you and then you can always adjust as needed.

Answer 2

The advice isn't necessarily contradictory, both methods are valid depending on what you want to achieve. Running out of moisture in a braise is a bad thing, so if I'm braising something with limited moisture then a tight lid keeps the liquid from evaporating. A good example would be when I cook beef shin, I add a cup of water and a cup of wine, and that's all, so I don't want to lose any of it.

In some recipes you start off with more moisture than you need, or there are ingredients which are going add to the moisture in the pot as they cook (think peppers, zucchini, cauliflower). In these cases keeping the lid off a bit allows the excess water to evaporate, thickening up the cooking liquid.