March 28, 2021

3 Factors that Affect How Beans Cook

Learn about three factors that affect how beans cook.

When I take the time to cook dried beans, I’m never disappointed. But dried beans are finicky. You need to soak them to reduce the amount of time they take to cook. You have to cook them at a low simmer so they don’t disintegrate. And there are certain factors that change the way they cook.

But beans are worth it, friends. So let’s talk about the factors that affect how beans cook:

  1. Dropping acid 🤪
  2. Turning up the base 🔊
  3. Swimming in salty water 🧂

If you’re interested in how to cook them, check out this past newsletter on cooking dried beans.

🤪 Dropping Acid

Alright, let’s talk about acid’s effect on your brain, I mean beans 😬. Acid prevents the pectin in the bean’s cell wall from dissolving. And if pectin doesn’t dissolve, beans won’t easily soften. So be careful cooking beans with acidic ingredients like tomatoes, wine, or citrus juice. Otherwise, your dried beans will take a long time to go from crunchy to creamy. This is HUGELY IMPORTANT (sorry got a little carried away there) when making any kind of bean soup. Because let’s be real. What’s a bean soup without tomatoes?!? 🍅

So what’s a lover of hearty soup gotta do? You’ve got two options my dears:

  1. Stagger your cooking. Wait to add tomatoes or a splash of wine to your pot until your beans are almost done. With less time in an acidic environment, the quicker the beans will cook since nothing is preventing the pectin from softening.
  2. Cook the beans separately. This is my preferred way to do it. You have greater control to make sure your beans cook to the perfect consistency. Plus Jack might come for a visit since you’ll have leftover bean stock. 🥁

But you can also make acid work in your favor, and you don’t even have to move to Berkeley! What if your beans start to finish cooking before you want them to? Drop some acid! You’ll slow down the cooking process so your beans are done right on time.

I love having a batch of slighlty undercooked cooked beans on hand in my refrigerator. Why undercooked? Because I know they’ll soften as they sit, and heat up in whatever dish I use them in next. Just soak some beans on Saturday. And then cook them on Sunday with more neutral flavors like garlic and bay leaves. Easy peasy beansy!

🔊 Turning Up the Base

If we go back to chemistry class, we might remember that the opposite of an acid is a base. No not that bass 🔊. The alkaline one. Baking soda is the most common form of a base in the kitchen. Don’t worry, if you skipped chemistry class like I did, we won’t get too technical here. It’s all pretty basic...See what I did there. 😉

Here’s what we need to know about bases and beans. When beans are exposed to an alkaline environment (created by adding baking soda to water), the pectin in the beans breaks down. This makes the beans cook faster!

What does this mean for cooking beans? To speed up cooking time and make sure your beans fully soften, add baking soda to your cooking water. Cooks Illustrated did an experiment. When they cooked beans in plain water, they found it took 60 minutes for the beans to turn tender. And only 45 minutes for the beans cooked with baking soda in the water! For the last batch, they added citric acid to the water. That pot took a whopping 1 hour and 45 minutes to get tender! 😮 See! And you didn’t believe me about acid making beans take longer to cook.

While I don’t think baking soda is a necessity when cooking beans, it’s a good trick to have up your sleeve. For example, I always add baking soda when making bean purées like hummus. This makes sure you get an extra creamy consistency.

Just keep this in mind. Add too much baking soda, and you’ll get a soapy, bitter taste. About ½ teaspoon per cup of dried beans is all you need!

🧂Swimming in Salty Water

Contrary to some tall tales in kitchens of old, unlike acid, salt won’t make your beans tough. In fact, it does the opposite. Sodium replaces the calcium and magnesium ions that bind pectin together. They’re responsible for making strong cell walls. So sodium softens the cell walls by switching places with those structural ions. So in order to soften the skins of beans, soak AND cook your beans in salty water.

Interestingly, salt also affects how much water beans absorb. J. Kenji Lopez-Alt did an experiment where he tested batches of beans. He saw two interesting things:

  1. Beans soaked in salted water absorbed less water than beans soaked in unsalted water. And less water absorption means a more concentrated bean flavor!
  2. Beans soaked and cooked in salted water had a lower percentage of burst beans! For the unsalted cooking and soaking water, 28% of those beans burst vs only 5% of beans soaked and cooked in salted water. Crazy right?

Here’s the takeaway. Salt softens the skins giving you a more tender, creamy texture. It also prevents water absorption, which means you get a more concentrated bean flavor. And lastly, it reduces the chance that your beans burst. So long story short, use salt when soaking and cooking beans!

Where I learned this: The Science of Good Cooking by Cooks Illustrated, On Food and Cooking by Harold McGhee, Six Seasons by Joshua McFadden, and this article J. Kenji Lopez-Alt.