What Am I Trying to Wash Off My Lettuce, Exactly?

November 2, 2019 7:08 AM

Okay, so we're supposed to wash lettuce. What am I trying to wash off? How long? Am I supposed to use soap? (Yuck.) What am I doing to myself if I just do a quick rinse under the faucet?
posted by musofire to Food & Drink (24 answers total)

I wash all produce. But then, I also don't use bags for produce at the grocery store, I just toss that stuff right into my cart. For lettuce, I peel off and discard 2-3 outer leaves which may be overkill, and then rinse the remainder under the faucet to remove any dirt/bugs. Soap sounds like a very bad idea, don't do that.
posted by stray at 7:17 AM on November 2, 2019 [3 favorites]

Lettuce is one of the most pesticide-contaminated vegetables (because its delicate leaves are delicious for bugs, etc.) Also, often there are little bugs and dirt hanging out in the interior of a head of lettuce, like, between the leaves.

Personally, I do not use soap. (Do you wash your other vegetables with soap?! Is this a thing people do?! I don't think I have ever eaten a single vegetable washed with soap in my entire life. Now I'm paranoid.) I fill a tub with water and break the head of lettuce into individual leaves, soak for a couple minutes, gently scrub off any obvious dirt with a finger, then use a salad spinner to get the lettuce dry. The soaking also helps rehydrate the lettuce leaves and make my salad crisper.
posted by branca at 7:18 AM on November 2, 2019 [5 favorites]

Dirt, mostly, but also bugs and pesticides and some forms of bacteria.

You are not supposed to use soap. Rinsing under the faucet helps, but if you have time, just letting your lettuce sit in a cold water bath for awhile will clean it and also hydrate your lettuce so it is nicer.
posted by jacquilynne at 7:18 AM on November 2, 2019 [7 favorites]

Whenever I wash lettuce I just pull the leaves apart from the base and rinse them under running water. You're trying to get off any dirt and maybe any pesticide residue.

Don't use soap. You don't want to eat soap. Soap tastes bad and will make you sick. I spent 15 years in restaurant kitchens, no one uses soap to clean vegetables.
posted by ralan at 7:20 AM on November 2, 2019 [6 favorites]

I take the head of lettuce and remove the end, then plunge the full leaves in a bowl of cold water and swish around. Empty the bowl and refill, plunge and swish again. Put the lettuce in a spinner to remove the water, then let it sit on dish towels on the counter to dry more. Then I wash and dry the bowl, pile the dried lettuce in it, cover it with a damp paper towel, and stick it in my fridge. It stays pretty well for the week. Each night I take a handful of leaves, rip them into smaller pieces, and have a salad with dinner.

I’ve never used soap to clean food.
posted by sallybrown at 7:23 AM on November 2, 2019 [12 favorites]

I vaguely recall reading somewhere that lukewarm salt water is most effective at removing pesticide residue? But TBH I just run veggies, including lettuce and cabbage, under cold water while scrubbing them lightly with my fingers, and I've never had any issues.

With leafy veg in particular, you'll usually have at least a little bit of dirt between the leaves, and store-bought lettuce is prone to E. coli contamination as well. So that and whatever small amounts of pesticides that remain on the plant are what you're washing off.
posted by tobascodagama at 7:30 AM on November 2, 2019

This site refers to a Stanford review of studies evaluating pesticide removal by various washing methods. They suggest using baking soda for leafy greens:

Fill a salad spinner with greens, then fill with water.
Add a teaspoon of baking soda and mix well.
Soak your greens for a minute, swish, dump, then rinse, and spin dry.
If you don’t have a salad spinner, you can add the greens, water, and baking soda to a bowl, let them soak, drain in a strainer, rinse, then pat leaves dry with a clean lint-free kitchen towel or paper towels.
posted by Botanizer at 7:31 AM on November 2, 2019 [9 favorites]

Best answer: The USDA Food Safety and Inspection Service says:

Before eating or preparing fresh fruits and vegetables, wash the produce under cold running tap water to remove any lingering dirt. This reduces bacteria that may be present. If there is a firm surface, such as on apples or potatoes, the surface can be scrubbed with a brush. Consumers should not wash fruits and vegetables with detergent or soap. These products are not approved or labeled by the U.S. Food and Drug Administration (FDA) for use on foods. You could ingest residues from soap or detergent absorbed on the produce.
posted by mbrubeck at 7:37 AM on November 2, 2019 [3 favorites]

I'm not very careful about washing produce but I always wash heads of lettuce; it has dirt and bugs in it. (Bags of prepared lettuce are designed to be used without washing). Get it thoroughly wet and rinsed, maybe rubbed for the dirty parts. No soap! The key thing afterwards is a good salad spinner to dry the lettuce off afterwards, so your salad is not soggy.
posted by Nelson at 7:38 AM on November 2, 2019 [1 favorite]

Best answer: "store-bought lettuce is prone to E. coli contamination as well"
this is very important and should be reiterated. I was working at my university CSA and one of the people I worked with was an agronomy major studying e.coli contamination in irrigation lines. We stood together cleaning all the produce to be packed as he explained his research to me.

I was hit and miss before, but I always clean my produce now.

(Also, just the other day I had to rescue a caterpillar from my organic lettuce that was already washed, torn up, dried and dressed. Leaves trap things! )
posted by wellifyouinsist at 7:55 AM on November 2, 2019 [3 favorites]

My nephew had a bad tapeworm infection. My SIL said it was because she hadn't washed organic produce because she thought it was safe to eat. I wash everything because I was brought up that way, like others, I use my salad spinner. Let it soak for 10 or more minutes, drain, rinse and spin.
posted by mumimor at 8:41 AM on November 2, 2019

The strongest reason to wash is to reduce exposure to bacteria like E. coli.
posted by ocherdraco at 8:47 AM on November 2, 2019 [2 favorites]

The strongest reason to wash is to reduce exposure to bacteria like E. coli

Agreed. The only time this can be avoided is if you're buying lettuce grown in an indoor farm (Aerofarms, Plenty, etc).
posted by pinochiette at 9:19 AM on November 2, 2019

Yeah, I usually do the baking soda thing for most fragile like veggies and fruits. For lettuce at least, if you bash it down on the counter stem end down, then you can just pull the stem bit out and have an easier time turning it into a bunch of leaves. If you do something like broccoli, re-cut the stem before you rinse it and let it sit for a while to plump back up with fresh water. (like cut flowers, the fresh cut is better at letting the water in.)
posted by zengargoyle at 10:17 AM on November 2, 2019

This past month here in Chicago the lettuce has been particularly dirty probably because of the heavy rains we have had kicking up mud into the lettuce before and during its harvesting.

If you don't rinse the dirt off your salads will taste very "earthy" in a literally way and have a really awful grittiness.

Consumers should not wash fruits and vegetables with detergent or soap. These products are not approved or labeled by the U.S. Food and Drug Administration (FDA) for use on foods. You could ingest residues from soap or detergent absorbed on the produce.

Uhm... the plates I eat off are washed with detergents or soaps and so are my hands....so ....? (not that I use either soap or detergent on produce but this little caveat seems very strange to me).
posted by srboisvert at 10:47 AM on November 2, 2019 [2 favorites]

I sometimes use vegetable wash, which is soap for vegetables but usually I just rinse. It depends where they came from.

Btw, E Coli is often inside the plants and you can't wash it off.
posted by fshgrl at 11:20 AM on November 2, 2019

Tiny baby slugs are a strong reason to rinse lettuce. In the old days living in a country with endemic cholera, dysentery, typhoid etc, the advice was to wash veg eaten raw in dilute potassium permanganate solution or dilute milton. This left a slight taste but you got used to it.
posted by glasseyes at 11:54 AM on November 2, 2019

Washing vegetables is recommended is you want to avoid toxoplasmosis.
posted by gakiko at 12:39 PM on November 2, 2019 [1 favorite]

Uhm... the plates I eat off are washed with detergents or soaps and so are my hands....so ....?

One assumes your plates are not nearly as porous as produce.
posted by ktkt at 1:35 PM on November 2, 2019 [7 favorites]

Depends on soap. There's that whole British thing where they just wash dishes in soap and don't rinse them. Their soap for washing is different than US soap for washing. Baking soda is a mild surfactant which reduces the surface tension of water much like soap/degergent does but is pretty not-yucky. The major action of dish soap is the same, but you don't want it absorbed into the food and need to wash it off (at least US versions). The detergent bit of dish-soap (and laundry-soap) type of things is an oil emulsifier... your veggies aren't oily, so need no detergent.

Washing veggies with 'soap' has a couple or more things. You don't want the detergent (no oil), you do want the surfactant (make the water a bit 'wetter'), and you'd like a bit of anti-fungal/anti-septic to maybe kill off some things while washing. Hence the baking soda or vegetable wash or salt-water or vinegar sort of treatment for wasing your veggies. NO SOAP (probably eww). Your hands have skin and are a good barrier, veggies are going to soak up a bit of whatever you're trying to clean them with.
posted by zengargoyle at 6:56 PM on November 2, 2019 [1 favorite]

I remove the end put it in a colander/strainer/steamer insert for a pot and rinse it under my sink sprayer. Then I shake it dry over the sink and then let whatever left drain/drip from the colander over a doubled paper towel. (I’m not going to make room for a salad spinner, I have a small kitchen and can get by with my arms.)
posted by snuffleupagus at 8:01 PM on November 2, 2019

I have seen this veggie prewash sold but I’d assume it’s meant for other vegetables that have a skin and/or may have a thin wax coating for transport and shelf life. Like bell peppers or cucumbers.
posted by snuffleupagus at 8:03 PM on November 2, 2019

To support the warnings about e coli, the FDA just announced that there was an e coli outbreak, from Romaine lettuce, in September. They didn't identify it until it was over, and they didn't find the source. People did get sick.
posted by Kirth Gerson at 6:32 AM on November 3, 2019

You are supposed to wash produce in general to remove pesticides, but lettuce in particular actually tastes better after washing.
posted by w0mbat at 2:54 PM on November 3, 2019 [1 favorite]