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Are cells living by the time you eat them? I'm guessing for very cooked foods they're quite dead, but perhaps (some or all of) the cells constituting certain other food sources are alive by the time they reach the mouth?

rumtscho
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Noah J
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    What would you consider “living”? Cells don’t have beating hearts. – Sneftel Jun 19 '23 at 21:37
  • I would bet there are living things in sushi. But perhaps you don't want to get a microscope and have a look. – Steve Chambers Jun 19 '23 at 21:39
  • @Sneftel while this question may be difficult for a philosopher, the word has a very clear meaning for everyday, practical purposes. As long as it actively maintains homeostasis, it's living. – rumtscho Jun 20 '23 at 09:04
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    @rumtscho Thank you for your intriguing definition of life. Can you take that further --- What is homeostasis? Is it (from Wikipedia) ``the state of steady internal, physical, chemical, and social conditions maintained by living systems''? If so, then we would be explaining life by referring to a concept which refers to life --- not very helpful. Do you know of a good explanation of homeostasis that does not depend on the notion of life? – Noah J Jun 20 '23 at 18:56
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    @NoahJ yes, that's what I mean. No, I don't think that there is a notion of homeostasis that doesn't depend on the definition of life. As I said, if you try to define life formally, there is no good definition. But luckily, that's a problem for philosophers. The concept is perfectly usable and clear in everyday situations, such as being able to determine whether a cell is dead or alive. – rumtscho Jun 20 '23 at 20:54

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If you eat fresh vegetables and/or fruits, then the cells certainly can be alive. Every time you eat a fresh (i.e. not cooked) salad or similar you are eating living things.

Almost all plant parts will survive quite a period out of the soil and retain "freshness", which indicates that they are alive - so much so that you can take a cut stem or even a leaf, place it in water and have it generate a whole new plant. This is known as vegetative propagation.

bob1
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  • Amazing! Okay, cooking kills plant cells --- how much cooking (to the extent that this can be answered generally)? Does freezing them kill them (or an appreciable sum of them)? Does bacterial or fungal spoilage kill them (or an appreciable sum of them)? Does time alone kill them (supposing that, somehow, spoilage due to bacteria and fungi were to be prevented and that things like moisture, temperature, and light conditions were kept ideal for the given plant matter)? Are the cells of raw meat alive? Please let me know if these should be asked elsewhere. – Noah J Jun 19 '23 at 22:18
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    @NoahJ the answers there are "it depends" Freezing in a freezer generally does - but plenty of plants survive freezing temps too (think snow in many countries...). Time, yes, if deprived of water and nutrients, otherwise maybe - hydroponics works for growing plants.. Spoilage will kill them over time - the bacteria/fungi are eating the cells for nutrients. Raw meat cells - for a while they are alive, but once they use up their energy source (ATP) and oxygen, they will die - any meat you get from a butcher/supermarket is well and truly dead. – bob1 Jun 19 '23 at 22:52
  • @bob1 nitpick: I tried to think of edible plant parts that go through a freezing cycle and couldn't think of any. We eat a lot of non-perennials, or plant parts that are protected from freezing (e.g. onion bulbs in the soil), or botanical fruit that isn't there in winter (e.g. aubergines). Perennial plants tend to survive winter with only hardy parts being out unprotected. As soon as the cytosol freezes and punctures the cell walls, it's over. – rumtscho Jun 20 '23 at 10:31
  • ... not to mention all the microorganisms that are alive in any raw food you eat. – FuzzyChef Jun 20 '23 at 17:09
  • @rumtscho -I quite agree, other than some specialist things like spruce buds, I don't think there are any. I was thinking kale and possibly some of the other brassicas might be possibles, but these are mostly harvested before the snows set in. However there are plenty of plants that we can freeze then cook and eat, so I think that makes this a valid point. – bob1 Jun 20 '23 at 20:54
  • @FuzzyChef I was discounting those as they aren't the bulk of the food source, but good point otherwise. – bob1 Jun 20 '23 at 20:55
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    @bob1 yes, talking about frozen vegetables is quite valid in the context of the question. I just don't think that there are any vegetables which will survive after freezing, independently of the fact that whole plants can survive a harsh winter. So I would put frozen-then-thawed vegetables in the "no longer alive" category. – rumtscho Jun 20 '23 at 20:56
  • @rumtscho absolutely. Kale is hardy down to -23 C/10 F, so it could survive freezing potentially, though not in the context of leaves removed from the plant I suspect. – bob1 Jun 20 '23 at 21:11
  • @rumtscho ordinarily not, not from standard cutting cloning, however depending on how it's been frozen, you can sometimes do tissue cloning. It depends on the veg itself, and the method of freezing. Some seed germs require freezing to be viable in the spring. I realize that's a germ, but it still kinda counts I think. – Escoce Jun 21 '23 at 17:40
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    @Escoce I'm with you on that one. Seeds may be dormant, but I sure count them as alive. – rumtscho Jun 21 '23 at 18:28
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Regarding sushi, some sushi is served fresh as in, killed right in front of you. That tissue is certain still viable.

Regarding things like beef, that's usually aged several days before it's even butchered, and then often aged some more. That's not usually still viable tissue.

Obviously veg that has been served fresh is still living tissue, since depending on what you have you could clone or culture a new plant from the tissue samples.

Then there are live cultures (that have not been pasteurized); Pickles, Kimchi, Sour Kraut, Yogurt, Sour Cream, Cultured Buttermilk. Yes you are consuming live lacto bacillus or similar bacteria in that case.

Escoce
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  • I forgot to mention wine, beer, kambucha, and kefir – Escoce Jun 21 '23 at 17:39
  • Oh yes, good thinking! I forgot about all fermented stuff. This is probably the prime example, because many people specifically consume it *for* the live cultures. – rumtscho Jun 21 '23 at 18:27