One might argue that Thanksgiving leftovers are among the most delicious things on this earth. Is that just because the cooking is over, the kitchen is clean, the company is gone — or do leftovers really somehow taste better?
Joining us this week to explain the science behind it all is Kantha Shelke from the Institute of Food Technologists. She’s the Founder of Corvus Blue LLC, a Chicago-based food science and research firm. Here’s a transcription of her interview with Pulse Host Maiken Scott.
What kind of food tastes better on day two or three?
Foods that contain a number of ingredients, a variety of ingredients, usually improve over time because each of the components sort of change during the cooking process and the aromas and flavor compounds that they release rejoin each other and form some complex characteristics, tastes and flavors and that’s what tastes better and better over time.
So the process of the flavors combining is not done when I turn the stove off, that process keeps going on even in the refrigerator?
Actually, yes. Cooking does not stop as soon as you turn off the stove or take the dish off the stove or out of the oven. It continues to cook, heat and even in the cooling process, the way these flavor molecules, the proteins and the starches interact with each other, and with the liquids, the fats, etc., all of those have a lot to do with how your food tastes later.
So why do we taste the foods differently a few days later? Is there also something about how the food hits our taste buds?
Absolutely, yes. When you pack leftovers away and bring them out and reheat them, the act of reheating actually mobilizes the flavor compounds and the aroma hits you first. On Thanksgiving Day, there are a lot of aromas happening because there’s a lot of cooking going on, but when you’re heating leftovers, it’s only what you’re heating. And that is pretty concentrated, it’s nostalgic and it takes you back to a lovely place and the food usually delivers.
The flavor compounds – the herbs, the spices, the reactions that take place during cooking, sort of cool back and depending on how you have cooled and refrigerated your food, actually get back into the food and get trapped into the starches and the proteins. The second time around, what you taste is not the distinctly different flavors, but the meld of tastes and that is what most of us call comfort food. So the mashed potato doesn’t stand out but it has also the aroma of the butter, the dressing and the gravy, it’s all melded together and it’s mellow and we love to taste mellow food.
What about texture? Does that change a lot?
Texture is very important. Let’s take turkey for example. There’s a reason why people ask us to remove the turkey from the oven and wait for a while. What you’re doing is allowing the cooking to continue, but what you’re really doing is allowing the protein, the collagen, the various juices to sort of cool down and solidify and trap the flavor. As you wait, the aromas diffuse through this big bird and even the inside tastes better. In the case of leftovers, what you’ve done is actually chopped up the pieces and put some broth on top of that. So when it cools, it picks up the aroma and the flavor of the broth and becomes tastier than the first time around.
What’s the trajectory of leftovers? If the food tastes better on day one, does it taste better on day two and then when does it start to not taste so great?
Most foods taste better 24 to 36 hours after they’ve been cooked simply because of this continued process that allows the flavors to intermingle and the textures to ripen and mature, after that, deterioration happens.
When you cook, do you cook to always have leftovers or do you perhaps cook a day ahead so you can store your food and let it rest a day?
It depends on the type of food. Turkey is best served on the day because there is something magical about that brown, crisp, golden-colored bird coming out. That’s not easily reproduced when you cook it the previous day. Some dishes such as potatoes, the vegetables, when made the previous day, particularly if you’ve used some spices, actually taste much better.