Wikipedia:Reference desk/Archives/Science/2017 March 11

Welcome to the Wikipedia Science Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

March 11

Why does salt make food taste better?

I boiled baby spinach leaves in water in a big pot. In a skillet, I cooked tofu cubes on the skillet and turned so that both sides appeared brown, indicating that it'd be crispy. The spinach diffused green color to the liquid. I transferred some spinach broth and spinach to a bowl and added the tofu cubes. It tasted bland. But adding salt made the food more palatable. Why? 107.77.194.158 (talk) 01:31, 11 March 2017 (UTC)

You develop a preference for foods with salt concentrations similar to what you are used to. You can even train this by forcing yourself to eat food with salt concentrations outside your normal comfort zone (either high or low) for several weeks. So if you start adding only half the normal amount of salt to your soup for a few weeks, thereafter the original amount of salt may start to taste excessive. Your salt preferences can also change based on how much salt you've eaten that day. Here are just a few studies on these effects: [1][2][3]. Going on Google Scholar and searching for something like "salt taste preference" will turn up a nearly unlimited number of studies of this phenomenon. It's even true for other mammals, such as mice. Someguy1221 (talk) 01:39, 11 March 2017 (UTC)

Within a certain range, yes, but sodium is an important nutrient, so we all will crave it, to some extent. Unfortunately, this nutrient rarely occurs in quantity in natural foods (other than seafood) but is now common in prepared food, so our cravings, which were appropriate when it was rare, are now unhealthy, when it is common. Note that we have salt-detecting cells on our tongues: [4]. Also note that "too salty" is highly unpalatable, although that threshold will vary by individual. StuRat (talk) 01:42, 11 March 2017 (UTC)

If you are trying to reduce sodium intake, one way to deal with bland foods is to add other spices, such as peppers. The capsaicin can fix the bland problem. However, be careful when using something like hot sauce, as those are often high in sodium, too. StuRat (talk) 01:55, 11 March 2017 (UTC)

In my case, I started enjoying hot sauce with my food when I discovered Sriracha sauce (Huy Fong Foods), which in my opinion makes other popular hot sauces taste vile and malodorous by comparison. I noticed the fairly high sodium content, but I also noticed that if I used enough to where sodium is an issue my mouth would be a volcano. A little goes a long way. --Guy Macon (talk) 02:56, 11 March 2017 (UTC)

Too sweet for my taste, and too much — something. Vinegar? Garlic? Not sure. Anyway I prefer or Tapatío or Cholula. But de gustibus and all that. --Trovatore (talk) 03:26, 11 March 2017 (UTC)

Using my 2nd link below, those have 110mg and 85mg, respectively, per 5 g serving. StuRat (talk) 18:10, 11 March 2017 (UTC)

Yea, looks like 60mg per 5g serving: [5]. That's not bad, as long as you keep to that serving size, although this source puts it at 100mg per 5 g serving: [6] and lists others with ranges from 26mg to 220mg, so it's worth shopping around. StuRat (talk) 03:07, 11 March 2017 (UTC)

Recreational drug use in animals

In what ways do animals use drugs recreationally, and which drugs?

Perhaps I should qualify: I mean wild animals consuming substances e.g. plants, at least in part, because of the effect of the drug. I believe that animals consume opium poppy latex, but I am not aware of any other recreational drug use in animals.--Leon (talk) 09:10, 11 March 2017 (UTC)

It's sometimes claimed Catnip#Effect on cats for various cat species although I'm not sure whether this happens in the wild much. The range for catnip and various Leopard and probably Lynx and catnip would seem to overlap so it's possible. Nil Einne (talk) 09:35, 11 March 2017 (UTC)

I don't know the quality of this source [7] but you could probably search the examples and it also mentions 2 books that would seem to be of interest. P.S. The examples in the above source also seem to be sourced themselves with RS. Although some of them are newspapers the bigger issue is probably the website's interpretation anyway. Nil Einne (talk) 09:40, 11 March 2017 (UTC)

• Apparently dolphins have taken to chewing puffer fish, as was reported just lately. Andy Dingley (talk) 10:13, 11 March 2017 (UTC)

Reindeer are known to like fly agaric. Cheers ✦ _hugarheimur 11:20, 11 March 2017 (UTC)

Birds are known to get drunk on fermented berries. Jahoe (talk) 12:41, 11 March 2017 (UTC)

Pigs like to eat fermenting apples, apparently. --TammyMoet (talk) 14:47, 11 March 2017 (UTC)

The widely held belief that elephants get drunk on fermented fruit has been shown to be a myth. Roger (Dodger67) (talk) 18:35, 11 March 2017 (UTC)

Sigh.

Belch (and awaaay we go....)

Ref regarding dolphins chewing puffer fish.

Ref for reindeer eating mushrooms and also discusses several other animals that consume psychoactive substances.

Ref regarding birds getting drunk off of berries.

Another generic ref on the subject, with a link to a more scholarly disputation on the drunk elephant story. Matt Deres (talk) 19:29, 11 March 2017 (UTC)

FWIW, the source I linked above before all of the replies (I did add the P.S. after some of them) includes this video of dolphins [8]. It also suggests the mushroom thing applies to moose as well as caribou/reindeer but I'm unclear whether the book it uses Animals and Psychedelics: The Natural World and the Instinct to Alter Consciousness ISBN 978-0892819867 mentions moose since it's not discussed in the abstract/reviews. It also mentions several more animals for alcohol including bees, fruit flies and monkeys although I'm not sure the later 2 are in the wild (well ignoring the book mentioned there which was referring to humans).

There are a few other cases mentioned there not mentioned here yet like big horned sheep and lichen. As well as cattle, sheep and sometimes horses with locoweed, although I guess for these you could dispute whether this counts as in the wild but it has given rise to a word wiktionary:locoed. It simplifies a bit but from the refs it uses, it's been sheep at least don't seem to get addicted [9] but cattle seem to learn the behaviour socially [10]. More info on locoweed and lichen is probably found in the other book it mentions which it uses as a source for that info Intoxication: The Universal Drive for Mind-Altering Substances ISBN 978-1594770692.

Also mentioned in the source I linked is an example of what the OP referred to namely wallabies consuming opium. The elephant thing is new, the posting is tagged with elephants but from what I can tell they aren't mentioned in it. (They are mentioned in the first book which seems to predate the dispute.) Nil Einne (talk) 20:41, 11 March 2017 (UTC)

Just to be clear, no part of my sigh had anything to do with the posts of people who posted references. Matt Deres (talk) 22:50, 11 March 2017 (UTC)

• Our article on locoweed says that "some individual animals seek it out". -Arch dude (talk) 02:52, 12 March 2017 (UTC)

The chemistry of ice cream

Chemically, what is ice cream? How can ice cream be low fat? I thought the fat part of milk is required in ice cream production. Can coconut flesh be grounded up into a creamy texture and then frozen at slightly below zero Celsius by ice cubes and salt while the mixture is constantly mixed by shaking the bag? Is this how commercial coconut ice cream is made? Avocados are high in fat. Why are't they made into commercial ice cream? Why are coconuts, almonds, and soy used instead? 107.77.194.195 (talk) 16:30, 11 March 2017 (UTC)

Ice cream is your source. The so-called "low fat ice cream" used to be called "ice milk" because it had very little fat content. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:03, 11 March 2017 (UTC)

"Low fat" is a relative term in the US. For example, 2% milk can be marketed as "reduced fat" compared to whole (4%) milk and one-percent milk can be described as "low fat" in comparison. What is marketed as reduced fat icecream in the US is not the same as "ice milk" and the brand I buy (bought) seems to use carb-based emulsifiers to maintain a fatty texture that icemilk does not have. Now I am off to seek ice-milk.... μηδείς (talk) 17:49, 11 March 2017 (UTC)

While fat, or something that simulates fat, is required to avoid ice crystals and get a creamy feel, shaved ice is another approach. As long as the crystals are small enough, they aren't too annoying. As for avocados, they can be used, but do have a flavor, so only work with strong flavors, like chocolate, that would cover up the avocado taste. Vanilla ice cream made with avocados would taste like avocados, not vanilla. Bananas can also simulate the fat, so frozen bananas in a blender can make a passable dessert. StuRat (talk) 17:52, 11 March 2017 (UTC)

Most industrial produced ice cream today is simply foam, representing 30-70% air or gas. Foam guarantees a soft, creamy texture and ofcourse at the same time its very, very, very cheap. You may notice icecream today is always sold with a volume declaration and there is never a weight declaration.

Ofcourse if you could read "2 litres/700 g" you would not pay more then the equivalent for 2 litres of milk, which seems a common prizetag, because you woult assume there is ~0.5 litres of milk in that at best. Often there isnt even any milk in it at all and usually it only contais Propylene glycol, some cheap fluid, some cheap fat and lots of sugar, in a masterful, cheap mixture you can not distinct form pure frozen whipped cream. --Kharon (talk) 22:23, 11 March 2017 (UTC)

Not in the U.S. where ice cream must contain milkfat to be called "ice cream". [11] Rmhermen (talk) 02:00, 12 March 2017 (UTC)

Likewise in NZ & Australia [12] "not less than 100g/kg of milk fat, and not less than 168g/litre of food solids". If it's something else it will be labelled as frozen dairy dessert or frozen confectionary or something else, see the earlier link and e.g. [13]. I can say most 2 litre tubs of ice cream or not ice cream I've weighed here in NZ are at least 900g and more commonly 1-1.1kg. This includes the container but that's only about 50g. That includes a fair amount of water of course.

While it may be correct the use of volume makes it less clear how much stuff is actually in the container, I'm unconvinced people's knowledge of the mass of stuff in it is a big factor in how much they will pay. After all people may tremendous amounts for cups of coffee but most people have some idea how much the beans etc cost. Heck even for things like chocolate or a lot of other things, while I wouldn't be surprised if people overestimate how much the ingredients cost, they tend to know the actual cost is a lot lot less than the product.

I'd also note that most liquids including milk are often sold by volume. Definitely here in NZ you wouldn't expect weight on the bottle of milk or coke or cream or oil even if it's not that different from volume. (Butter and spreads tend to be sold by weight, although mayo is an interesting one where some go buy weight and some volume.) Heck Coke and other soft drinks are another great example of people knowing the ingredient cost is a lot lot less than the product. And yet plenty of people still buy them. I mean heck here in NZ you can get Coke for perhaps 3 for $5 1.5L bottles on occasion yet plenty of people will happily buy them at $2.50 or more that they are more commonly sold at (and this isn't even the ordunary retail price in many supermarkets).

Nil Einne (talk) 13:51, 14 March 2017 (UTC)

Radium Fission

Is any radium isotope fissile?32ieww (talk) 17:30, 11 March 2017 (UTC)

See radium. StuRat (talk) 17:56, 11 March 2017 (UTC)

Does it answer the question? Dbfirs 18:25, 11 March 2017 (UTC)

Wikt:fissile defines the word as "capable of undergoing nuclear fission", so any radioactive isotope would seem to qualify. However, the OP may have meant it in a more restrictive sense, like "usable to make a nuclear weapon or power a nuclear reactor". StuRat (talk) 18:32, 11 March 2017 (UTC)

Well almost any substance can decay. Even protons decay eventually. See Fissile material. Dbfirs 18:36, 11 March 2017 (UTC)

Looks like Wiktionary may need to be updated to show this diff between Wikt:fissile and Wikt:fissionable. They are currently treated as synonyms there. StuRat (talk) 18:41, 11 March 2017 (UTC)

Before 1965, the American Nuclear Society decided that "fissile" should refer to "those heavy nuclides which can be fissioned by thermal neutrons". Dbfirs 18:43, 11 March 2017 (UTC)

Looking at Isotopes of radium, no isotopes of radium are listed as undergoing fission. Radium atoms with masses 221-226 can undergo cluster decay, which according to that article "is a type of nuclear decay in which an atomic nucleus emits a small "cluster" of neutrons and protons, more than in an alpha particle, but less than a typical binary fission fragment."--Wikimedes (talk) 19:56, 11 March 2017 (UTC)

Ra is not fissile. You find fissile nuclides from Th onwards. Double sharp (talk) 04:08, 13 March 2017 (UTC)

Research question: What's in a typical carpet?

Someone suggested attempting to write an article at Wikivoyage on "Carpet Safari" for April 1st.

This got me thinking, as I wasn't sure what to put in such an article as I am not entirely sure what might be relevant.

So does anyone have a guidebook to what flora and fauna may be present in a typical carpet? ShakespeareFan00 (talk) 19:05, 11 March 2017 (UTC)

Not every question has an answer. Look up yurt, Persian carpet, and indoor-outdoor carpeting, as well as dust mite and nematode. A more specific question could be answered more specifically. μηδείς (talk) 19:19, 11 March 2017 (UTC)

Seek and ye shall find. See Your home is a jungle inhabited by 100 different species, What Lives in Your House (Besides You), 50 Interesting Facts about Carpets, and Uninvited Guests: Invisible Creatures Lurking in Your Home. Alansplodge (talk) 20:03, 11 March 2017 (UTC)

No problem with those sources, except that they all refer to British infestations. What "carpet" means is not limited to that isle. μηδείς (talk) 19:04, 13 March 2017 (UTC)

How indestructible are military dog tags? (morbid)

I was thinking about the metal ID tags that military personnel wear, as do some other extreme activity people, and was wondering, how tough are dog tags? House fires burn at about 1500-2000ºF, and stainless steel melts between 1600 and 2200º depending on type and thickness. So would it be more likely that (in the unfortunate event of a firefighter dying in a blaze) that their tags wouldn't survive, but would like warp or the letters would be smeared and thus of no use? Another possibility is that the metal could become malleable enough that a falling object could crush or deform the tags? Thanks L3X1 ( distant write ) 20:24, 11 March 2017 (UTC)

You should check your (false) temperatures.--TMCk (talk) 21:02, 11 March 2017 (UTC)

"In typical house fires, temperatures seldom reach 650 degrees C." Manual of Forensic Odontology, Fourth Edition edited by Edward E. Herschaft (2007) p. 46. Alansplodge (talk) 21:30, 11 March 2017 (UTC)

Which is 1,200F (so, not close to 2,500F, the melting point of steel, but at least let's keep using the same scale). Matt Deres (talk) 22:23, 11 March 2017 (UTC)

Most are made of iron steel sheet metal. Something suitable, like SAE 310S stainless steel, has a melting range of 1354 – 1402°C °C or 2470 – 2555°F °F. --Kharon (talk) 22:42, 11 March 2017 (UTC)

Thanks Kharon I didn't know that. L3X1 (distant write) 22:48, 11 March 2017 (UTC)

(edit conflict) Thanks for the feedback, I am fruitlessly trying to track down the Google search that gave me the stainless steel temp. But regarding house fires, 1200 is only the average. Chimney fires (which can spread to the house) can easily break 2000ºF. Also hot spots, and other structure fires can get lots hotter than 1100ºF, and while no department would send in firefighters, there is the possibility that they could of died while the fire was smaller, and the bodies were unable to be retrieved by other crews before the blaze intensified. So I'll take all this as: Yes, their indestructible unless something above average happens. L3X1 (distant write) 22:46, 11 March 2017 (UTC)

Chimney fires are not the type of house fire fireman put out and I don't think Santa is wearing a dog tag :)) --TMCk (talk) 23:11, 11 March 2017 (UTC)
...and "fireking" certainly not a reliable nor believable source.--TMCk (talk) 23:15, 11 March 2017 (UTC)

I must be missing something from you first statement "Chimney fires are not the type of house fire fireman put out". Fireman do put out chimney fires, and chimney fires can turn into attic fires which constitutes​ a structure fire. I'm not a firefighter, but I've seen chimney fires on STATter911.com, and it still is missing the point. The avg. house fire temperature doesn't exclude the fact that other types of structure fires could be closer to 2000ºF. But I've seen to have answered my own question, below the destruction temps of steel, dog tags are indestructible by heat. Above the melting point of steel, poof. Thanks for y'alls time.L3X1 (distant write) 23:23, 11 March 2017 (UTC)

The point is that chimney fires can be the cause of a "regular" house fire but it's not the ch. fire itself that is put out, and no fireman will crawl into a chimney.--TMCk (talk) 23:29, 11 March 2017 (UTC)

• All that discussion about fusion temperatures sounds awfully like a "jet fuel can't melt steel beams" argument. The fire temperature is lower than the melting point, but the yield strength decreases sharply with temperature, see [14].

If the fireman/soldier is "only" on fire, then the plate will not be subject to meaningful stresses so it will not be destroyed, but if (e.g.) the roof of the building collapses and rocks fall over the plate, damage may be significantly more than one would expect from a room-temperature test. Tigraan^{Click here to contact me} 10:20, 14 March 2017 (UTC)

References

Ice falling from aircraft

What happens to ice which falls off aircraft as a result of the aircraft's anti-icing systems activating? Does this ice eventually fall to the ground below, or does it get absorbed in air? If it were to fall from the ground at thousands of feet above the air, then it would probably be hazardous for whatever/whoever it strikes on the ground, right? 173.52.236.173 (talk) 23:46, 11 March 2017 (UTC)

Whether it's hazardous would depend on the size and shape of the pieces. A small piece would not carry much kinetic energy even if falling rapidly, and furthermore, it would also have a low terminal velocity. --76.71.6.254 (talk) 00:26, 12 March 2017 (UTC)

See Ice falls from aircraft.--TMCk (talk) 00:26, 12 March 2017 (UTC)

However, that page refers to two other reasons that ice may fall off, rather than anti-icing systems as in the question. --76.71.6.254 (talk) 00:34, 12 March 2017 (UTC)

Oh. I didn't know that de-iced ice falls different than non-de-iced ice.--TMCk (talk) 01:08, 12 March 2017 (UTC)

See above: if it forms pieces of different size and shape, then it will. --76.71.6.254 (talk) 08:31, 13 March 2017 (UTC)

In reading De-ice, I'm not so sure your initial premise is likely. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:05, 12 March 2017 (UTC)

The fate of the falling ice is also dependent on the temperature of the air through which it falls. If the air temperature is below freezing all the way to the ground, most of the ice can be expected to reach the ground; but if there is a substantial layer of air whose temperature is above freezing, the ice will melt and disperse as a bunch of rain drops that may, or may not, evaporate before reaching the ground. Dolphin (t) 11:59, 12 March 2017 (UTC)