Serious Eats / Amanda Suarez
Where I grew up in India, it was common practice to wash ingredients before cooking, including all types of meats and chicken. Only when I moved to America did I learn that washing meat, especially chicken, was discouraged by food safety authorities like the FDA, USDA, and CDC. Given the official stance of these federal agencies, and the scientific studies that support their advice, this article could start and end with a simple statement: Do not wash your chicken because science and the US government say so.
But chicken washing remains a common practice around the world (90 percent of respondents in one 2013 study claimed they still do it), and so the question lingers. Even in the 1990s, Julia Child and Jacques Pépin had a friendly back-and-forth about it on an episode of their TV show Julia and Jacques Cooking at Home—Julia told Jacques that she washed her chicken with hot water, and then Jacques very pointedly made clear that did not. Whom to trust?
Let's get right to the point: While we have some lingering questions about the don't-wash-chicken edict and believe the subject can be approached with a bit more nuance, overall we think the evidence is clear that washing raw chicken is not generally a great thing to do.
Let's now take a closer look, because it's worth digging into the science and the studies that have contributed to our understanding about the relative risks and merits of chicken washing.
Why Do People Wash Their Chicken?
To state the obvious, people wash chicken out of a perceived need to clean it. In modern times, this can be driven by the desire to remove microorganisms like bacteria, but even before people knew of the existence of these invisible germs, it often made sense to wash meats to remove debris, traces of blood, and other unwanted or inedible matter. Just as one example, the chicken I used to buy in India went through fewer steps from slaughter to sale than most of the more industrial chicken I see here in the United States: The butcher killed the bird and then cleaned, cut, and packaged it right there, and I’d take it home to be cooked. It often had some remnant matter on it that we at home wanted to rinse off.
The cultural and agricultural contexts influencing chicken washing is something that has been pointed out by journalist and YouTuber Adam Ragusea in his insightful video on chicken washing. Ragusea hypothesizes that in parts of the world where more of the population remains more directly connected to agriculture, there could arguably be a greater need to wash a chicken of things like feathers and clotted blood that are less likely to be found in a shrink-wrapped supermarket chicken that gets thoroughly washed as part of its industrial processing. Plus, Ragusea links the frequency of the practice to parts of the world that tend to be hotter, where, especially in pre-refrigeration times, spoilage would happen more quickly.
This gets us to the other reason people often say they wash chicken: to remove an unappealing flavor, often described as "raw," from the bird prior to cooking. The editors at Serious Eats have heard this explanation frequently, often from contributors who come from countries where chicken washing is more common. In these cases, the washing often involves more than simply rinsing the bird with water—rubdowns with citrus, salt, and other seemingly cleansing ingredients are part of the process. Ragusea, in his video, wonders whether this "raw" flavor is really just the first signs of spoilage that might be more common in hotter climes, though we're not so sure that's it. Rinsing meat to remove unwanted flavors is something Serious Eats editors have heard from recipe writers from many countries around the world, some hot, some not.
Why Do Scientists Say Not to Wash Chicken?
The argument against washing chickens is all about harmful bacteria, specifically Salmonella, and it goes like this: When you wash chicken, you risk spreading those pathogens all over your kitchen via splashes and droplets of contaminated water as they land on surrounding surfaces, counterintuitively increasing the chances of foodborne illness instead of decreasing it. You're not cleaning your chicken, you're contaminating your kitchen!
A quick internet search reveals multiple studies that have looked at this phenomenon, and they tend to come to the same conclusion that washing chicken doesn't do much to help, and very possibly can hurt. Based on estimates from the CDC, every year one in six Americans gets a foodborne illness, 128,000 Americans are hospitalized, and 3,000 die. Salmonella specifically, which is the one we're most concerned about with chicken (though not the only one), is estimated to cause more than one million illnesses annually, 19,000 hospitalizations, and nearly 400 deaths.
In 2003, scientists at Campden BRI, an organization that works with the food industry on scientific, technical, and safety matters, published a detailed report on how bacterial contamination can occur during the handling of meat. This study examined various types of meat like chicken, beef, lamb, and pork and how bacteria transferred to two types of common kitchen surfaces—laminate surfaces and stainless steel. Not only did they find that wet meat transferred higher levels of bacteria, but they also noted that stainless steel surfaces had more bacteria transferred to them than laminate surfaces, and the bacteria persisted on these surfaces for 48 hours.
Since washing chicken doesn't seem to remove enough bacteria to make raw chicken safe, and since it seems to spread that bacteria around, it's therefore not recommended as a practice.
The Data: A Closer Look
Several of the chicken-washing studies I read sought to determine and understand the risk of spreading bacteria. Most of these studies involved applying a dye to the chicken (which could then be seen if spread elsewhere) or dosing the surface of the chicken with cultures of bacteria (which could then be detected by taking cultures of different nearby surfaces to see how much germ spread had occurred). The studies routinely reported finding the dye or bacteria on the surfaces surrounding the sink, indicating that washing chicken is highly likely to spread bacterial contamination.
While there is no denying that washing raw chicken and meat can spread bacteria in the surrounding areas, I had several unanswered questions after reading the published literature. They include:
- How do we know if the manner in which the raw chicken in the studies was artificially loaded with dye or bacteria accurately replicated the bacterial load on raw chicken obtained from stores? The answer to this wouldn't change the basic finding that, yes, washing can spread bacteria in harmful ways, but it might have implications for the level of risk in real-world scenarios (that risk might be less or more, depending on the answer to this question).
- How did each study account for the shape and dimensions of the sink where the raw chicken was washed? In this study, for example, the chicken and the trays used to collect the "projecta" (the potentially contaminated spray droplets) were placed at the same height. In reality, most sinks are deep basins so it makes interpreting the results from this study a little tricky. Other studies were done in actual sinks, though not all sinks are the same size, depth, or shape, which may also have some bearing on risk levels.
- Faucet height and design matter, as they can impact the flow rate and force of water hitting the chicken, assuming one is washing the chicken under running water and not in a basin of water. All of this can influence the way the water droplets fly off the surface of the chicken, with lower faucet heights and lower water flow rates in theory causing less splashing.
- What are the relative risk levels between washing chicken in prefilled bowls of water versus under running water? We know that washing chicken under running water is the riskiest of all, but by how much? It's possible that the advice should really be to avoid washing chicken under running water; maybe gently lowering a raw chicken into a prefilled bowl of water and then carefully discarding that water down the drain is much less of a concern.
These questions aside, I also wonder about the basic fact that these studies were carried out in such controlled conditions in the first place. Of course scientific studies need to be carefully controlled, there's no way around that, but it could have some implications for the conclusions we draw. For example, in most home kitchens, the sink is almost never a clean place. It's the place where dishes linger with standing water and remnants of food waste, where hands that have touched raw chicken get washed, and where raw chicken itself is often removed from its packaging—specifically because there's often excess raw chicken liquid (called "purge" in the poultry industry) that also can carry pathogens, and that comes sloshing out as soon as you unwrap the chicken. This stuff is going to get all over your sink too, whether you wash the chicken or not.
In a laboratory setting where the sink starts out sterile, then gets exposed to raw chicken splatter via washing, and then is swabbed to detect that splatter—sure, we're gonna find the germs from that splatter and declare all chicken washing bad. But any kitchen where raw chicken has to be handled is going to have exposures as well, it's simply unavoidable. The sink is not a clean place, and shouldn't be considered as such.
This, of course, wouldn't change the fact that splatter caused by running water hitting the chicken has been found to extend outside the sink—that still seems like a pretty big problem we'd want to avoid—but it might make some of the other findings, in the content of a real kitchen where real raw meat is being handled no matter what, a little less alarming.
Conclusions
While I agree that water splashing on raw meat can transfer bacteria in the kitchen, there are broader implications to consider, and both details and context are very important. The findings from the studies on chicken washing and the resulting recommendations are good as far as they go, but they make me wonder if home cooks wouldn't be better served by a more general emphasis and education on basic cleaning best-practices and food safety.
Some actions that we might want to pay closer attention to include:
- washing/cleaning our hands, food-prep tools, and kitchen surfaces regularly, especially before and after touching raw meat, but also before and after cooking;
- reserving separate cutting boards for working with raw meat;
- and being mindful of how we store and prepare fresh produce that isn't going to be cooked to avoid cross-contamination with raw meats.
If you do decide to wash chicken, avoid doing it under running water from the faucet, and take care to avoid and/or contain any and all spatter or other transfer of wet matter that has been in contact with the raw bird.
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