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Have you ever substituted a black lentil with a green one? And did you also end up with mushy lentils that were supposed to go into a salad but seem more at home in a soup? In other words, did you think all lentils would probably behave the same way and that color is just appearance?
If so, I think I like you :-). I run into these issues, all the same, thinking something in the recipe isn’t important. Whereas that specific attempt likely won’t be as successful (but you can still it mushy lentils as part of a salad!), you do learn a lot better by failing this way. I probably wouldn’t have even thought about the lentil types as much if I would just duly follow the recipe.
So, in order to help you either understand why your food failed (if you ended up Googling for an answer) or to prevent failure, we’re going to have a look at how to choose your lentil!
What are lentils?
The lentils that we humans grow for food are all related and grows on a plant called Lens culinaris. These plants stay pretty low, it’s closer to wheat than it is to corn. After flowering these plants grow seed pods. It’s in these seed pods that the lentils grow and develop.
Like most other legumes, the Lens culinaris plant can bind nitrogen. This is important for farmers, but it also means that they contain a lot of protein (nitrogen is an essential part of protein). If you would take out the water of the lentils, about 20-30% is protein. It’s one of the reasons lentils and legumes make up such an important part of diets around the world.
Aside from the protein the lentils contain barely any fat (1%) but do contain a significant amount of carbohydrates. About half of this is made up of starch which ensures that the lentil becomes nice and soft during cooking.
After harvest the lentils are removed from these pods. You’re left with a small (they’re some of the smaller legume types), round, pretty flat lentil. Each lentil has an outer seed coating that protects the inner seed, called the cotyledon.
Even though lentils all grow on that same plant species, within that species there still is a lot of variation. A common way to distinguish between all these types is based on color. The name either represents the color of the seed (which is generally more brightly colored) or that of the skin.
Alternatively, you can also distinguish lentils by size. Lentils can have a diameter anywhere from 3-9 mm. Different regions, prefer different sizes.
Globally, the largest group of lentils are the orange lentils. These are lentils with an orange seed inside. They tend to have a red/brownish or even black outer skin. Even though these lentils are more orange than red, they are generally sold as red lentils. Red lentils tend to be the smallest lentils sold, although there is still quite a wide range of sizes sold worldwide. Which size you’ll find where you live depends on your region’s preference.
As you can see in the photo below, the bright orange colour can be hidden beneath a dark brown skin!
The other major group are the yellow lentils, again, this color describes the color of the seed. As you can see in the photo below, those green lentils ‘hide’ the yellow center.
Apart from these brighter colored ones, green lentils also make up a significant portion of the world’s lentil production. The seed of green lentils is almost never really green, instead, these seeds are also yellow(ish).
The main processing step that lentils go through after they’ve been removed from their pods is drying. Manufacturers reduce the moisture content to <15% to ensure the lentils keep well and don’t spoil during storage. The lentils don’t undergo other major modifications. They are ready to eat as such.
Once the lentils are dried they can be kept for a very long time. Lentils (like most dried legumes) don’t go bad over time. They can be stored for years.
In some cases manufacturers do decide to process the lentils a little further. A common step is to remove the seed coat from the lentil. It’s why you can buy those bright orange lentils. The seed coating has been removed from them already.
Even when the coating is removed, the lentils will still remain good for a long time.
The seed of a lentil generally is made of two halves pressed and held together by the seed coat. Once the lentils are deshelled the two halves often fall apart quite easily. As such, in many deshelled lentils you will see both cases of the two halves together as well as a split version.
In the store you can find shelled lentils from which the seed coat has been removed as well as lentils that still have their shell on. Lentils won’t be sold with their pod in which they’re grown.
Cooking with lentils
Most legumes can take hours to cook. It takes a long time for those beans or chickpeas to become soft all the way through. Lentils are an exception here though. Especially the smaller varieties cook quickly, within half an hour. Of course, the exact cooking time will depend on the lentil variety, but also on its age and how it has been stored.
During cooking the starch within the seed softens, as does the seed coat. If
Mushy vs Firm lentils
So how do you either get a smooth soup consistency from cooked legumes? And how do you ensure that the lentil will remain sufficiently firm for use in a salad? There are two important factors to keep in mind here.
Shelled or not?
First of all, if a lentil does not contain a hull anymore, you will not be able to cook this into a firm sturdy lentil. Normally the shell holds the inside of the cooked lentil together, which is mostly soft starches. With that not being present all the starches spread out quite easily and you’ll end up with a thick smooth consistency without the recognizable lentils.
How long you cook your lentils for can make or break them. Over time, all lentils will turn into mush. Once the outer seed coat has softened enough and starts to break down, the center of the lentil will start to ‘seep’ out. This will result in mushy lentils, so take care!
If you’re using smaller lentils than the author of your recipe is, you’ll likely get a more mushy consistency. Also, if you’re using a different type, with a firmer or softer skin, you’ll likely end up with a different consistency.
Salt interacts with most legumes during cooking. Brining beans can soften the skins by softening the pectins. However, it can do the opposite for the lentil center. Salt can actually help to keep that together and firm it up!
Choosing & Using Lentils
So, if you’re using lentils. Stick to the times indicated in the recipe when you want them to come out firm and use the lentils that the author recommends! If you do decide on using another type, be sure not to use shelled lentils if you want them to turn out firm and keep a close eye on them when you’re boiling them by tasting regularly!
CBI, Exporting dried lentil grains to Europe, link
Erskine, William, The Lentil: Botany, Production and Uses, United Kingdom: CABI, 2009, link
Plants of the World Online, Lens culinaris Medik., visited April-2020, link
Cook’s Illustrated, Cook’s Science: Chapter 24 Lentils, 2016, link