Wikipedia:Reference desk/Archives/Science/2014 January 4

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January 4[edit]

Minimum size that the tongue can feel[edit]

Hi there,
I would like to know what is the minimum scale of a particle of which the tongue can feel.
In other I would like to know the resolution of the touch sense in the tongue.
Another question will be whether the teeth split cell when you eat meat etc...
11:58, 4 January 2014 (UTC) — Preceding unsigned comment added by Exx8 (talkcontribs)

A Google Scholar search on "intraoral tactile sensitivity" gives plenty of results - this paper in particular concludes that the typical tactile resolution of the tongue is between 0.5 and 1 mm. See Tongue for our article. On your second question, only plant cells have a cell wall, so meat cells will either be split up when the meat is cooked or when it's eaten - see Meat and Denaturation (biochemistry). Tevildo (talk) 12:42, 4 January 2014 (UTC)[reply]
That seems way too big. I think that paper is talking about not being able to distinguish two particles which are that close together, versus what the OP asked about, which is how small of a particle can be detected at all. StuRat (talk) 14:57, 4 January 2014 (UTC)[reply]
Since the latter would depend on the mass and texture of the particle (not to mention its taste), as well as its size, I doubt any meaningful figure could be given. Also I suspect the tip of the tongue is more sensitive than, say, the back of the tongue. Maybe it's also desensitized in some people due to smoking or hot foods. Tactile sensitivity (distinguishing between two particles) is the more usual measurement.--Shantavira|feed me 16:03, 4 January 2014 (UTC)[reply]

Using a stainless steel mixing bowl for cooking soup[edit]

I'd like to make my own version of a double boiler by placing an 11 inch stainless steel bowl in a bath of boiling water in a steaming basket in a large stock pot. The object is to make it impossible to burn the soup.

I don't have the bowl yet, but am about to buy it. Most of the stainless steel bowls I see are called "mixing bowls" or "prep bowls". So, my question is, can these bowls take boiling temperatures ? (Presumably stainless steel itself can, but I'm worried they may have some type of coating which can't.)

I also considered a ceramic bowl, but was worried that it might also have a coating that can't take boiling temps, and it might crack, too. StuRat (talk) 16:07, 4 January 2014 (UTC)[reply]

If you just want to keep the soup warm then the vessel doesn't have to withstand boiling temperatures. Are you going to make the soup from raw ingredients, or will you be reconstituting a packet of soup? --TammyMoet (talk) 17:11, 4 January 2014 (UTC)[reply]
From raw ingredients. StuRat (talk) 17:26, 4 January 2014 (UTC)[reply]
It seems to me that buying a double boiler would make more sense. The great majority of stainless steel bowls are uncoated and wouldn't be damaged by boiling, but using a bowl is not a very good idea anyway, because the narrow base makes it likely to tip. Looie496 (talk) 17:20, 4 January 2014 (UTC)[reply]
I can only find small double boilers in local stores, suitable for making at most a pint of soup at a time. I already own one of those. I want to make a gallon of soup at a time. Plus, if I could find such a large double boiler, it would probably cost a fortune. A simple stainless steel bowl ought to be a lot cheaper. An 11 inch diameter bowl can fit in my 42 quart stock pot. As for tipping, hopefully sitting the flat bottom on the steamer basket will prevent that. StuRat (talk) 17:26, 4 January 2014 (UTC)[reply]
  • AS an experienced cook and waitrix with an undergraduate degree in biology, I can assure you there's nothing chemically problematic with a stainless steel mixing bowl, but, as noted above, the shape is not really designed stablely enough for cooking. μηδείς (talk) 18:36, 4 January 2014 (UTC)[reply]
  • OK, then how about a stainless steel insert (basically a smaller stock pot without handles on the outside) ? What other terms should I use to Google such a thing ? StuRat (talk) 20:14, 4 January 2014 (UTC)[reply]
I've googled on Bain Marie and found all sorts of arrangements. --TammyMoet (talk) 20:31, 4 January 2014 (UTC) In fact, wikiHow has a picture guide to making one, which might help. --TammyMoet (talk) 20:33, 4 January 2014 (UTC)[reply]
Thanks. I looked at those instructions here: [1]. That example just involves balancing one pan on another, which doesn't seem very stable, and doesn't allow a lid to be put over the big pot, to prevent (or at least delay) it from boiling dry. StuRat (talk) 20:56, 4 January 2014 (UTC)[reply]
With a Bain-marie one should not need a Teflon coating, because the food does not form a thick coat (although you might still need a scourer and detergent to off get what remains). If you want to simply heat up gallons and gallons (or as Carl Sagan might say – billions and billions of cubic centimeter of soup) then a [commercial bain marie] may be your cheapest solution. Do let me know of your next soiree. My family are expert culinary critics and will fly out to you, with their doggie bags, etc.--Aspro (talk) 21:04, 4 January 2014 (UTC)[reply]
That link doesn't work for me. StuRat (talk) 12:09, 5 January 2014 (UTC)[reply]
Have you thought of a Crock-Pot? They show up regularly at thrift stores - cheap ~E:71.20.250.51 (talk) 00:04, 5 January 2014 (UTC)[reply]
Hah, that's exactly what I was about to suggest. Looie496 (talk) 01:09, 5 January 2014 (UTC)[reply]
I hate to buy yet another cooking appliance. Also, cooking with electricity is more expensive than the natural gas I use now, and I understand that some slow cookers have hot spots, so get burned food stuck to them, especially if I make something like beans, which wants to burn anyway. StuRat (talk) 11:57, 5 January 2014 (UTC)[reply]
  • The safest way to go here is going to be with a crockpot that has both a thermostat and a timer. Whether you risk rigging your own bain-marie or go the safer route and buy a well-designed one you cannot leave it unwatched, and the water will run out. The only good thing about a bain-marie in the eyes of a restaurant cook is that it is the busboys who have to scrub it clean when it burns. μηδείς (talk) 00:21, 6 January 2014 (UTC)[reply]
“The only good thing about a bain-marie in the eyes of a restaurant cook is that it is the busboys who have to scrub it clean when it burns.” Forgive me for being a smart-ass here. You have over looked, that a charred pot leaves the food with a unpleasant bitter taste. Even in alcohol distilleries, they use steam pipes to heat the liqueur in the still so that charring does not take place. The 'burnt toast' taste, is the nearest thing that come off the top of my head.--Aspro (talk) 00:40, 7 January 2014 (UTC)[reply]

Plasticers leaching into food[edit]

UPDATE: I found these slow cooker liners: [2]. Hopefully I can place one of those around the steamer basket, and make my soup/beans in there, with no possibility of it burning. I'm a bit worried about plasticizers leaching out, though. Now for the science part of the Q: Which plasticizers do these bags use, and what, if anything, prevents them from leaching into the food ? Also, if they do leach into the food, does it affect the taste, and is it unhealthy ? StuRat (talk) 11:57, 5 January 2014 (UTC)[reply]

You've probably seen it because it is linked from the page you linked above, but [3] at least gives a little information. It's made from the same plastic as their line of oven bags and the plastic is BPA-free and approved by the FDA for cooking. If you trust the liners, then this shows that their oven bags are an option as well if the size or price works better for you. Katie R (talk) 16:21, 6 January 2014 (UTC)[reply]
FWIW. I hate plastic bags but cooking bags makes life simpler. My cooking bags are made of Nylon. From what I understand, is that Nylon is naturally flexible and so doesn’t require any plasticizers. They are great for Sous-vide, where I can prove to the mother-in-law, that I 'am a better cook than her precious little child, that married a ne'er-do-well that could only play a guitar, had long hair and could not play not the piano. Mind you, I know were middle C is now – I highlighted it with a bright yellow marker.--Aspro (talk) 01:05, 7 January 2014 (UTC)[reply]

Chemistry atomic orbitals[edit]

We have the electron configuration of a carbon atom is C: 1s2 2s2 2p2 . Is it more stable for the carbon atom if an electron from the 2s orbital to go to the 2p orbital for this orbital to be half filled? Thank you! — Preceding unsigned comment added by 77.42.251.200 (talk) 19:09, 4 January 2014 (UTC)[reply]

  • No. I believe Chromium and Copper are the only anomalies like this among the lighter elements (non-relativistic). The repulsion from the 2s1 electron is insufficient to make the 2p3 state a lower energy.--Gilderien Chat|List of good deeds 20:10, 4 January 2014 (UTC)[reply]
There's a nice diagram here showing the energy levels of a carbon atom. The 2s1 2p3 is a little more than 4 eV above the ground state. There's also a handy web form at NIST where you can try various other atoms if you're interested (but note that you have to use spectroscopic notation). --Amble (talk) 23:27, 4 January 2014 (UTC)[reply]