The staff at America’s Test Kitchen prides itself on testing all their recipes dozens of times, tweaking them every which way possible to achieve perfection. In the process, they’ve come across many ironclad rules of the kitchen that have turned out to be not so ironclad after all. Doc Willoughby is editorial director for magazines at America’s Test Kitchen. He collected some of his favorite myths they’ve busted over the years and shared them with Splendid Table host Francis Lam. One of the myths is about marinades and whether they work or not. After hearing his argument, try the America’s Test Kitchen recipe for Grilled Shrimp Skewers with Three Finishing Sauces: Spicy Lemon Garlic, Charmoula, and Fresh Tomato with Feta and Olives.

Francis Lam: Your team kindly sent along a list of the greatest hits of your myth-busting career at America's Test Kitchen. Before we talk about it, shall we prepare to be shocked or mildly surprised?

Doc Willoughby: I would say mildly surprised for most of them and possibly shocked by one.

FL: Which culinary myth are you most proud of slaying?

DW: The myth that marinating actually does anything.

FL: What?!

DW: This is a myth that is hard to slay. It's kind of like the myth that searing seals juices in meat, which was discredited back about 1989, but most people still believe it. Marinating is one we've just started to discredit a few years ago, so we have our work ahead of us.

John John "Doc" Willoughby Photo: America's Test Kitchen

FL: Tell me more, because I do not believe you. I love to marinate. I don't do it all the time, because I'm lazy.

DW: This is the best thing – when we're not believed – because, of course, we back everything up with science. Years ago, we started feeling like marinating doesn't seem do much, particularly when you're doing chicken or meat – which are the things people marinate most often. We decided to do an experiment. We took boneless skinless chicken breasts in four different marinades: soy, yogurt, red wine, and lemon and garlic. We left them in there for 18 hours. After that time, the marinade had penetrated less than between 1-3 millimeters, which is less than a tenth of an inch, and that's after 18 hours. We took the chicken breasts, shaved off the amount the marinade had gone in – the outer three milliliters – and roasted them along with other chicken breasts that had not been marinated. We had people taste them. No one could taste any difference at all.

FL: Wait, what?

DW: It was a blind tasting with a large panel of 30 testers. The only way you could taste any difference was if you tasted one that had not had that little tiny bit shaved off. Even then there was only a faint difference. Again, this was after 18 hours in marinade.

FL: That’s a long time.

DW: It's a long time; and no one wants to marinate anything that long. All marinating does is put a tiny bit of flavor on the outside part of whatever it is you're marinating. The other thing people say is that marinating tenderizes things. If you use acid – or the other thing people often use is papaya juice – theoretically, it will tenderize the meat, but only to the same depth as those marinades penetrated. All it does is make the outside mushy. No matter how long you marinate, you're only going to get mushy exterior and a tiny bit of flavor on the outside. It’s much better to skip marinating. Instead, cook the food and then put the flavor on it afterwards.

FL: Like sauce it. But what about a brine?

DW: Brining actually works. And here are the exceptions to my myth-busting.

FL: I knew it!

DW: Brine will carry salt into the interior of whatever you're brining at a different rate depending on what it is. The salt does season whatever you're brining and also makes it stay moister when you cook it. There are two items that are water soluble that you might have in your marinade: onion and garlic. If you have a marinade with onion and garlic, some of that flavor will get further into the meat. But all the spices, herbs, and most of the things that you want to add flavor, they're all fat soluble and don't penetrate meat or fowl. If you're marinating something like tofu, it has a very loose structure, so the marinade will penetrate the tofu. However, if you're marinating meat or chicken, you're not going to get much difference. If you put a lot of salt or soy sauce in your marinade, you will get a seasoned piece of meat or fish, but it won't have any additional flavor.

FL: I'm still having trouble digesting this. I'm not sure I entirely buy it, but I'll buy that we have some common ground where I can accept that the brine, salt and soy sauce work. What is another myth that you have busted?

DW: Here's another one that people have been doing forever on faith that it works. That is, when you roast a turkey or chicken, if you baste it, it will end up moister and juicier because you've been basting it. That seemed like one of those things that, while it's homey and fun to do, maybe it doesn't work.

FL: It’s fun. Everyone loves it.

DW: But does it work? We took three chickens and three turkeys. One set we basted every 20 minutes, the second set we just roasted without doing anything, and the third we didn't baste, but we opened the oven door and closed it every 20 minutes. When they were done, we measured the moisture loss in all three of them to see if any of them had stayed more moist. As it turns out – no. Moisture loss was virtually identical in all three. What happened was, it took 10 percent longer to cook the bird that we didn't baste but opened and closed the door; it took about 16 percent longer to cook the one that we basted. Because what you're doing when you baste is you are cooling down the surface of the bird. As it turns out, that doesn't keep it moister, it just makes it take longer to cook.

However, the one thing basting did do? It gave you a darker skin. If you don't mind cooking a little longer, and you know you're not going to get anything moister, you will get a better-looking skin by basting.

FL: I don't have any emotional attachment to basting, so you can tell me anything you want to tell me about it and that's fine.

DW: But you're still not believing the marinating?

FL: I'm still not buying the marinating.

DW: You have to do this for yourself at home, and then you'll believe it.

The next one is something that I'm very happy about. I love my grandmother and she was a great cook. But she always used to do things that I didn't think worked, and she insisted they did. One of them was, whenever she boiled corn, she put sugar in the water. She insisted this made the corn not only cook faster, but taste sweeter. When we were working on our boiled corn recipe – yes, we actually do have a recipe for boiled corn – we decided to figure out if this was correct. We took corn and we put it in water with blue dye; the chemicals in this dye approximate about the same structure as salt or sugar. We decided to see how long it would take the blue dye to get into the entire ear of corn. Guess how long it took?

FL: Well, you don't want to boil corn for more than…

DW: Take a guess.

FL: A few minutes?

DW: It took two hours.

FL: Oh, come on!

DW: The reason for this is that kernels of corn are not permeable; they're semi-impermeable. For the salt and sugar to get into the kernels. where you could taste them, it has to soak through the cob, saturate the cob and then go into the kernels. My grandma, despite her skill at cooking, was wrong about this.

FL: There is one more on this list. The myth is, "Exactly how you whisk makes no difference." And this is not a myth. [laughs] This is not a thing that people tell one another.

DW: This is the great myth of whisking! This is what happens when you have 42 test cooks in a kitchen, they're all doing something, and they want to figure out who's doing it the best and most efficient way. People have different ways of whisking – some do it in side to side, some do it in a circular motion, and some beat it, which is that looping thing where the whisk comes out and goes back into the liquid.

FL: That’s how I do it.

DW: You’re doing it the wrong way.

FL: You're killing me!

DW: We took these three methods and had a bunch of different people: left handers, right handers, people with small hands and big hands, all the variables. We had them emulsify vinaigrettes, whip small amounts of cream, and whip small amounts of egg whites. The worst one – the one that lost every one – was circular stirring. It took twice as long to whip cream and egg whites as in another manner, and the dressing never got fully emulsified.

The winner was side to side: this back and forth motion, never taking the whisk out of the liquid. The reason is that when you do that, it sets up what's called shear force. You’re going one way in the liquid and then you're going back, but some of the liquid is still coming the direction you were going before and runs into the other liquid. That’s shear force, and that makes everything mix faster.

All that said, beating is the way you do it. When you bring it out of the mixture and back in, that is the best for egg whites. It was very poor for emulsifying or for whipping cream, but it was best for egg whites. Otherwise, use the back and forth motion.

FL: Very cool.

DW: Aren't you glad I busted that myth for you?

FL:  That you invented that myth to bust it? Yeah, that's great. Plus, a chef once told me you have to do figure eights in the bowl, which I could never do.

DW: That might even be best! We will have to add that to our next round of testing.

America's Test Kitchen
The Splendid Table frequently visits with the test cooks at America’s Test Kitchen to discuss a wide range of topics including recipes, ingredients, techniques and kitchen equipment.