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Imagine the scenario. You are cooking chicken in a Bechamel sauce. First you fry the raw chicken in the butter, stirring until the chicken is partially cooked. You then add some flour, stir and fry some more. You then add milk, a stock cube and seasoning, stir well, bring to a gentle simmer, cover and stir occasionally until the chicken is cooked through.

  1. Will the utensil become sterile under these conditions or is there a risk of contamination from the raw chicken?
  2. Is there a difference in risk factor between utensil materials e.g. steel, silicone or wood?
  3. Could the risks in 1 & 2 above be eliminated by keeping the utensil in the covered pan during cooking rather than sitting on a utensil rest or dish?
Greybeard
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  • What about dishes that _don't_ involve significant amounts of sauce, such as stir-fries or fry-ups? (Or should that be a separate question?) – gidds Apr 16 '23 at 12:27

3 Answers3

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Making stuff sterile, in the medical sense, i.e. pathogen-free, is incredibly hard. You basically need an autoclave, and of course tools that withstand prolonged exposure to high pressure steam at well over 100 degrees, so wooden tools are right out, and any plastics will degrade very quickly.

What you probably mean is "food-safe" which is a far cry from sterile under normal conditions. As long as all participants in a meal are relatively healthy, i.e. not undergoing severe immunodepressant therapy, I personally wouldn't bother using several tools along the way, neither with eggs nor chicken nor fish. Stirring hot sauce will probably bring contamination down to reasonable levels within minutes, if not seconds, especially since you have the additional decontamination mechanism of "washing" the tool with the sauce.

arne
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Bacteria will not multiply and may begin to die once the temperature is over 140F (60C), but that doesn't make the situation risk free. Once at 212F (100C) you can be sure that you are killing bacteria. So all portions of the tool that were in contact (or were splashed by) food at a temperature below 140 (60C) ARE NOT risk free until those surfaces are above boiling. This DOES NOT mitigate the risk of clostridium and bacillus spores which are heat stable.

I will add that temperatures in these cases is often difficult to determine. Food is often below the boiling point. Most parts of the utensil are often below the boiling point. In your example as long as you are proceeding exactly as you describe, there is no risk because everything in the pan is cooked through. Your final dish is, of course, safe. The risk arises when a utensil that has touched a raw product like chicken is used for another application, thus creating a cross-contamination situation. Yes, you could submerge your spoon in the sauce as you cook it to ensure safety, but that sounds like an inconvenient mess. So, in this case, serving and/or eating with a clean spoon is probably a good idea.

moscafj
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    I suppose that the worry that the OP (and I for that matter) have is that while you say the final dish will be fine, you also are regularly stirring with the spatula and regularly are potentially re-introducing still-live bacteria. If that’s done within the last few minutes of the cooking process, I can see the worry since it may not have been held “at temp” for long enough, even if you swap to a clean item to serve with. – fyrepenguin Apr 14 '23 at 00:41
  • "a few minutes" in a bubbling sauce is probably enough to mitigate any potential risk. However, easy enough to be safe and grab a clean utensil once the outside of the raw protein has been in contact with high heat near the beginning of the prep. – moscafj Apr 14 '23 at 01:13
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    @moscafj If you could find guidance from official publications, that might help clarify. (I imagine that "best practices" for this sort of thing may be covered in the sanitation requirements for food service industry workers.) – R.M. Apr 14 '23 at 01:49
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    Yeah @moscafj I usually just swap to a clean utensil halfway through once stuff is mostly cooked, and give it some time before using the new one. Just a general thought about using/reusing the same utensil for the whole cook process. And as you mention, using a clean one for serving as well – fyrepenguin Apr 14 '23 at 05:13
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    @fyrepenguin "safe" and "sterile" are two different things. The cooked chicken itself is also not sterile. If reintroducing bacteria from using the same spatula throughout the cooking process was a problem, there would be strict rules against doing so. The question was about "sterile" and moscafj's answer is correct about that. – rumtscho Apr 14 '23 at 06:38
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    @rumtscho I'm generally assuming they mean "food-safe" and not "sterile" in the OP, as [this answer](https://cooking.stackexchange.com/a/123925/48468) discusses. Maybe the OP truly is interested in sterilization, but I'm not sure they are. – fyrepenguin Apr 14 '23 at 07:39
  • @R.M. There is a large gap between what happens in the food service industry and at peoples' homes, but "best practice" is to use one tool for raw foods and another tool for cooking/cooked food to avoid cross contamination. You generally don't find spoon rests, for example, in commercial kitchens. – moscafj Apr 14 '23 at 10:27
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    Yes, I sloppily used the word "Sterile" rather than "Food safe" as it seems more appropriate in this context, even although it will never actually reach that temperature point in reality. Using the term "Food safe" seemed clumsy here as I would hope nobody would be stirring dishes with a non-food-safe implement to start with ! – Greybeard Apr 14 '23 at 21:49
  • @Greybeard Strictly sterile is very hard ;-). (Oh, arne said that much, I see.) – Peter - Reinstate Monica Apr 16 '23 at 12:43
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Most cooking utensils will be non-porous, especially plastic or metal ones. Wooden or bamboo spatulas vary a bit depending on type of used wood, finish and age. This means that you do do not need to sterilize the entire spatula, just the surface. It also means that any bacteria clinging to the surface will be in direct contact with either hot sauce or steam almost immediately.

There is also the point that for most intents and purposes food doesn't need to be sterile. Perfect sterility is almost impossible to achieve in a home kitchen, you need high pressure steam for that. What a home cook is looking for is "is the bacterial load negligible enough that any stray bacteria can be cleared up by the immune system and stomach acid"

Bacteria aren't magic! Compared to things like rocks and metals they are creatures not unlike you or me. Compare it to deforestation: do you need to stamp on each and every acorn to declare an area "deforested"?

So a utensil that was clean to start with, non-porous, and in fairly limited contact with non-spoiled meat that itself was rapidly heating, stirring a pot of hot water or oil? Will be more sterile than you need within seconds.

Borgh
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    A non-porous surface is also be very easy to rinse most of the contaminants off of by putting it under a running tap for a few seconds. And then it doesn't leave a mess on whatever it's rested on afterwards. – Andrew Morton Apr 15 '23 at 15:01