How Do Restaurants Keep Lettuce So Crisp?

Published Categorized as Food
Two hands holding a head of lettuceKoldunov /Depositphotos

The secret to keeping lettuce crisp, as it turns out, is in doing the opposite of what people on the Internet tell you.

Everyone has had the following experience: you buy a bag of lettuce at the store. You throw it in the fridge. A few days to a week or two later, you take the lettuce out of the refrigerator and discover, to your disappointment, that it has gone limp. You find yourself forced to throw the bag in the trash and quickly change your meal plan.

When you go to a restaurant, lettuce—whether it is at a salad bar or served to you before the main course—is always perfectly crisp. It turns out that eateries have developed a simple technique to keep their lettuce crisp so it is never served to a customer soggy.

Contrary to popular belief, restaurants don’t keep their lettuce crisp by washing it immediately in cold water. Excess moisture promotes spoilage, they keep the lettuce refrigerated at low humidity, with the outer leaves intact, and use it within 3-4 days.

Simply put, don’t listen to what most folks have written—and rewritten—on the Internet. But don’t just take my word for it; here’s an extract from the textbook professional chefs are trained with:

“Most produce should not be peeled, washed, or trimmed until just before use,” says The Professional Chef, a book by the Culinary Institute of America (CIA), which trains the nation’s best chefs and restaurateurs.

Restaurateurs put much emphasis on purchasing and storing their produce well. They choose their suppliers carefully and scrutinize the greens, fruits, and veg they provide them with.

As a home cook, you can emulate this by choosing your lettuce scrupulously at the store—and refrigerating it with the right technique.

When selecting lettuce at the store, look for lettuce heads with a bright color and crisp outer leaves that feel firm and are heavy for their size. Don’t buy lettuce heads that show signs of discoloration, sliminess, or wilting.

At home, refrigerate whole heads of lettuce in the crisper drawer, with the humidity control set to low. Halved or sliced lettuce should be dried and stored in a storage container lined with some paper towels. The towels will soak up excess moisture and keep the lettuce crisp longer.

A Brief History of the Lettuce

While the sort of lettuce that we eat in a salad originated along the Mediterranean Sea coast, with the first being cultivated and eaten in Egypt some 6,000 years ago, the Greeks and the Romans adopted lettuce as their own.

After the fall of the Roman Empire, lettuce persisted in Europe. Columbus brought lettuce seeds with him on his second voyage for cultivation in the New World. Robert Winthrop, Jr. also brought lettuce from England to the American colonies in the 1600s.

Currently, various kinds of lettuce can be bought at the supermarket in the United States, whole heads or cut up and sealed in a bag. Lettuce has even gone to space, grown as an experiment onboard the International Space Station.

The astronauts ate some of the lettuce and the rest was transported back to Earth for analysis. The “space lettuce,” a form of Outredgeous romaine, is said to be quite as delicious and about as nutritious as the variety grown on Earth.

The Types of Lettuce: A Primer

As a general rule of thumb, two types of lettuce are common in the American supermarket: They are the iceberg lettuce and the romaine lettuce. Each type has certain advantages and disadvantages in terms of taste and nutrition.

Iceberg Lettuce

Iceberg lettuce is sold as a head of greens and is typically priced lower than other varieties at the store. Since it is about 95% water, it is low in calories. While iceberg lettuce has a reputation for being less nutritious than romaine lettuce, it does have vitamins A, C, and K, calcium, folate, and potassium according to the USDA’s FoodData Central.

Iceberg lettuce is a popular base for a salad that may also include red onions, carrots, crumbled cheese, slices of ham or pepperoni, and tomatoes. A leaf or two is also a good addition to any sandwich or hamburger—sometimes under the burger patty to keep the bottom bun from getting soggy; othertimes over any other toppings, just under the condiments on the top bun’s underside.

Iceberg lettuce has a very pleasing crunch but a somewhat neutral taste. It’s a favorite with children who tend to be picky about eating veggies.

Romaine Lettuce

Romaine lettuce is available in various types at the supermarket in bags for easy storing. The lettuce is packed with nutrition, the information at USDA’s FoodDate Central reveals, including vitamin A, C, and K, calcium, folate, magnesium, phosphorous, and potassium,

Romaine lettuce is great as part of a Caesar salad but can also be used for a regular salad with toppings like red onions, carrots, crumbled cheese, slices of ham or pepperoni, and tomato. It can be used as part of a sandwich or hamburger.

Romaine lettuce, shredded, can also be a great addition to fajitas, tacos or nachos. Leaves of romaine lettuce can even be used as the basis of a no-dough wrap. The idea is to spread the filling on top of a romaine leaf and then roll it up, securing it with a toothpick.

Making a Salad With Lettuce

People are divided into two groups: those who prefer the simple Caesar salad and those who like their salads with a little more variety.

The Caesar salad is the simplest thing in the world to make. You create a bed of romaine lettuce, add croutons and shredded parmesan cheese, pour Caesar dressing over the lot, and you have a tasty but simple first course.

The dish that most restaurants call the house salad is a little more complex. You start with the romaine lettuce, though some will prefer iceberg lettuce. Then you add a variety of toppings, including slices of red onion, Spanish olives (the Greek variety is a bit bland), diced tomatoes, shredded cheese, and pepperoni slices. The best dressing for this kind of salad is some varieties of Italian, though some prefer honey mustard, blue cheese, or ranch.

Cooking With Lettuce

Lettuce is generally served raw, either as part of a salad or as part of a sandwich. However, a number of dishes involve cooking lettuce. Lettuce features a lot in an Asian stir-fry.

Stir-Fry Garlic Lettuce

Stir-fry garlic lettuce involves taking some garlic and a pound of romaine lettuce and stir-frying it in a wok in a combination of rice wine, soy sauce, sugar and salt.

You cook the garlic in vegetable oil and then add the lettuce and the sauce. The whole process should take no more than about three minutes to make sure that the lettuce does not get too limp. Serve after drizzling with sesame oil.

Chinese Stir-Fry Lettuce

Iceberg lettuce is not typically considered something to be cooked because of its high-water content. But this recipe uses it because it is also crispy and will absorb any kind of sauce you use with it. You combine rice wine, soy sauce, and sugar as that sauce.

First, you cook some garlic, ginger, and pepper flakes, adding the lettuce and cooking until slightly wilted, Then you add the sauce, stir fry for a couple of minutes, and then serve with a topping of sesame oil.

Lettuce Soup

The ingredients for lettuce soup, besides eight cups of lettuce leaves, include onion, garlic, diced potato, and three cups of water. The mixture also includes pepper, salt, and coriander.

After bringing it to a boil and then simmering until the potato has become tender, the recipe calls for pureeing in a blender in batches, perhaps a risky proposition for a hot liquid. You could instead use a hand blender to puree the mix into a solid, green soup before simmering again until it’s warm enough to eat.

By Jim Stonos

When Jim isn't in the kitchen, he is usually spending time with family and friends, and working with the HCW editorial team to answer the questions he used to ask himself back when he was learning the ropes of cooking.