One of the keys to making a good salad is ensuring that your lettuce is fresh and crisp. Nothing makes for a disappointing salad like a plateful of limp, wilted greens.
There are two things salad greens need to stay crisp: moisture and air. You may have heard otherwise. Specifically, many people seem to think that the best way to keep lettuce crisp is to seal it up in a bag with all the air squeezed out.
I've even read some suggestions that involve inserting a straw into the bag to suck out every last molecule of air before sealing it shut.
Unfortunately, that advice is completely off base. Lettuce actually needs a good amount of air flow, in addition to a bit of moisture, in order to stay crisp. That's why restaurants store their lettuce in special perforated bins that allow for air circulation while it's held in the fridge.
(Removing the air does help prevent oxidation, which is what causes lettuce to turn brown, but has nothing to do with lettuce staying crisp. In any case, oxidation isn't something you should have to worry about as long as you buy fresh lettuce and use it within a few days.)
So here's the best way to keep your lettuce crisp at home:
Trim off the end of the stem and separate the leaves.
Fill up the sink (or a very large bowl) with cold water and submerge the leaves. Gently swish the leaves around in the water. Any grit will sink to the bottom of the sink. Remove the clean lettuce, or empty the bowl and repeat this step for especially dirty lettuce.
Now you're going to want to dry the lettuce. The best way to do this is in a salad spinner. But don't cram the leaves into the salad spinner. Cut the leaves in half (or smaller) so that you don't bruise them trying to squeeze them in.
Salad-spin until all the water has drained away. The leaves will still be slightly damp — that's what you want.
Now take the basket out of the salad spinner and cover the leaves with damp paper towels. Transfer the basket to the fridge. (You could use a large colander instead of the salad spinner basket.) You might want to set it on a plate or tray to catch any additional drainage, but don't use a bowl — remember, you want airflow.
Once the greens have chilled for about 30 minutes, they'll be crisp and ready to use. But you can store your lettuce in the fridge this way for 3 to 5 days. Rewet the paper towels if they dry out. Squeeze out excess water — they only need to be damp, not soaking.
Note that this technique is the exact opposite of the way mixed greens are sold. Mixed salad greens come either in a bag or in one of those plastic clamshell containers. Neither one of these storage methods allows for any airflow, which is why those types of greens turn limp so quickly after you buy them.
The good news is you can use the method described above for your loose greens, too. Yes, usually those mixed greens have already been washed, but remember, it's the residual moisture from washing and then draining the greens, along with the wet paper towel, that help keep them crisp and fresh, along with adequate airflow.
(Not to mention, bagged greens have been found to be the culprit in a number of outbreaks of food poisoning, so it's a good idea to wash them yourself anyway.)
With your greens fresh and crisp, you're ready to make a perfect green salad. Also, here are some tips for making a great vinaigrette.
