Wikipedia:Reference desk/Archives/Science/2009 December 17

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December 17

testicular torsion

what happen if the dead testicle is not removed post testicular torsion? —Preceding unsigned comment added by Reolmadrid (talk • contribs) 03:26, 17 December 2009 (UTC)

See the "Treatment" section of our testicular torsion article. DMacks (talk) 04:34, 17 December 2009 (UTC)

Explain why cancer has a genetic code?

Please explain how cancer has a genetic code, accoding to this http://news.bbc.co.uk/1/hi/health/8414124.stm I thought cancer was just the result of unlucky mutations caused by bad environmental things (like smoking, too much sun, sodium nitrate etc). I thought only a proper species would have a distinctive genetic code. 78.149.247.13 (talk) 10:46, 17 December 2009 (UTC)

I believe you are right about mutations causing cancer; if I'm reading the article correctly, it seems that they're just recording what those mutations are. The mutations are changes to the genetic code genome so the cancer cells do have a different code genome from the healthy cells, but it's not the necessarily the same for ever cancer cell as they are mostly random changes. I believe the hope is that by recording these they can gain insight into which mutations will cause cancer, so the oncogenes I guess. I haven't studied genetics too much so my answer is probably lacking in some way. Jkasd 11:33, 17 December 2009 (UTC)

We have an article on this, gene expression profiling in cancer, and see also oncogenomics. Note also, that a predisposition to some cancers can be hereditary (covered in the cancer article) and so these too, can be detected by looking for the genetic marker. SpinningSpark 12:17, 17 December 2009 (UTC)

One more article you may want to read is tumor suppressor gene. SpinningSpark 12:22, 17 December 2009 (UTC)

Your confusion is caused by an unfortunate oversimplification made by the journalist who wrote the article, not the scientists who carried out the research. If you read the article on genetic code, it explains that the "code" is the set of rules used by the cell to translate the instructions encoded in the DNA into the proteins that actually do the work in the cell. The "genetic code" is basically the same among all species, with some rare "variants" described in certain single-celled organisms. This is different than the genome -- the entirety of all the genetic information in a cell -- which differs between individuals, and which can accumulate mutations in different cells throughout the life of the organism. Mutations aren't changes to the "genetic code" but changes in the genome. The article title (and the answer by Jkasd) confuses the distinction between the "code" (which is invariant) and the "genome" (which can be highly variable). Cancer cells still follow the same "rules" when translating the genetic information. They just accumulate mutations that activate certain genes (see oncogene) or inactivate other genes (see tumor suppressor gene). Not surprisingly, they also accumulate a lot of mutations that probably have no effect at all. What many cancer biologists are doing these days is to examine "cancer genomes" to generate catalogs of all the mutations found in individual tumor samples, then to see whether the same mutations keep coming up over and over again in different people. This would give us additional insight into the mechanisms of carcinogenesis, and hopefully point towards effective treatments. --- Medical geneticist (talk) 13:27, 17 December 2009 (UTC)

computer CD ? DVD

what is the material of construction of CD & DVD ? what is the difference ( Construction) between CD & DVD ?193.188.60.123 (talk) 11:10, 17 December 2009 (UTC)

According to our article CD, they are mostly made of polycarbonate plastic with a thin layer of aluminum. I believe that DVDs are made of the same materials, the difference being the size of the pits and the format used. See Optical Disc for more general information. Jkasd 11:24, 17 December 2009 (UTC)

A big difference between CDs and DVDs that you can easily notice if comparing the two from the side is that in DVDs the reflective layer is in the middle i.e. there are two layers of plastics on the top and bottom. This is because the amount of information that can be stored depends how close the data layer is to the surface so by reducing the thickness of the protective layer they can increase the amount of information that can be stored. There's some explaination here [1] for example (related to Blurays where the data layer is even closer to the surface). Of course to keep the thickness the same as CDs, they add another protective plastic layer to the top. This also means that the reflective surface is protected from scratches unlike with CDs where it can be scratched (and if it is, you're basically screwed). It also means double sided DVDs are possible (albeit still fairly rare because people don't like switching sides) whereas with CDs they're not compliant with the spec. As I mentioned, this is usually easy to see if you look closely from the side and you can actually differentiate DVDs from CDs in a spindle (useful for example if you have a spindle and you're looking for a specific CD or DVD in a mix or you think you misplace it). Some DVDs particularly recordable ones don't bother to put any coating at the top (or it may not cover the whole top) so you can clearly see the reflective layer is underneath from the top side as well.

Of course DVDs can also be dual layer. This means there are actually two data layers each with a reflective metal layer (one being semi transparent) and a small protective layer in between. See [2] [3] for example (these are recordable but much of the same applies to pressed DVDs.) However they are close enough together that it can be difficult to see from the side. From the bottom however if you look at the spindle you should see two different rings perhaps with a different barcode and maybe even a different description (e.g. L0 and L1). One is for each layer.

Also when it comes to recordable DVDs you they use different dyes from CDs.

BTW because of the different track pitch you also get different diffraction grating patterns in particular, the spacing between the lines is wider with a DVD. This works best with a laser e.g. [4] [5] but as with anything involving lasers please take great care when trying that and make sure you know what you're doing. If you don't, you should be able to see this with an ordinary light although probably not well enough to accurately measure. From memory a small light works well, particularly if it has two or three peaks. For example, I had a mobile phone with a fairly long but narrow LED on top (you can see the LED in this photo, it's the transparent bit between the self potrait reflective button thing and the camera) that could shine different colours, it was interesting to see the different colours that made up these and it was also a good way to compare the diffraction patterns of CDs and DVDs.

Nil Einne (talk) 14:51, 17 December 2009 (UTC)

Particles And Black Holes, are They the Same Thing?

If a particle has mass, but is a zero dimensional point according to standard model doesn't that mean it has an infinite density meaning it is a black hole? I know that according to some theories like m theory, black holes and particles are remarkably similar,but if a particle has infinite density doesn't that make it a black hole. Black hole evaporate by releasing Hawking radiation, but no one knows for sure wether they completely evaporate into a burst of gamma rays after becoming a micro black whole or wether they reach some stable state and the process stops. If at some point black holes do become stable, could a particle actually just be its stable form? --74.67.89.61 (talk) 23:50, 19 December 2009 (UTC)Connor Goham —Preceding unsigned comment added by 74.67.89.61 (talk) 12:20, 17 December 2009 (UTC)

Those are some interesting questions. Our article on the black hole electron briefly touches on some of these points, including the issue of stability of such (hypothetical) particles. The answer to your final question boils down to, "Yes, that would be compatible with some models of physics." Unfortunately, we don't have now (and may never) have the tools necessary to probe the structure of matter on small enough scales to confirm or refute the presence of tiny black holes inside each 'fundamental' particle. TenOfAllTrades(talk) 13:48, 17 December 2009 (UTC)

Why does once in a blue moon = 1.16699016 × 10^(-8) hertz?

Says Google.

Why?--72.178.133.37 (talk) 14:04, 17 December 2009 (UTC)

Because a blue moon occurs on average every 2.7154 years and a year has 365.256363051*86400 seconds. Thus, a blue moon occurs every 2.7154*86400*365.256363051 seconds, or with a freqency of 1/85692999.878958419s or 1.1669564625027745e-08Hz (minor rounding errors may have occurred). --Stephan Schulz (talk) 14:18, 17 December 2009 (UTC)

I don't understand the hertz though. The article says that the unit is defined as "cycles per second". What is a cycle? I've never heard of that unit.--72.178.133.37 (talk) 14:21, 17 December 2009 (UTC)

From wikt:cycle - "An interval of space or time in which one set of events or phenomena is completed." --LarryMac | Talk 14:25, 17 December 2009 (UTC)

So how do you compare frequencies? Because when I think of frequencies, I think of radios (sound), radiation (light), and so forth. They all use hertz? Isn't that a bit impractical? I've never heard of, say, the frequency of some light being described in hertz (or megahertz or any size prefix).--72.178.133.37 (talk) 14:39, 17 December 2009 (UTC)

• You compare them (I'm not really sure what you mean by "how" there). Our hertz article notes, though, that "for historical reasons, the frequencies of light and higher frequency electromagnetic radiation are more commonly specified in terms of their wavelengths or photon energies". For known speed (in this case, c), frequency and wavelength can be trivially converted, so it's simply a matter of nomenclature. Visible light, for what it's worth, is in the hundreds of terahertz range. — Lomn 14:47, 17 December 2009 (UTC)
• Yes. Hertz is just another name for "1 per second" or 1/s. 440 Hz is the frequency of a sound in concert pitch A. That's 440 "cycles" or "vibrations" of the air going back and forth in one second. Around 100 MHz in the electromagnetic spectrum is FM radio. 550 THz EM is green light. --Stephan Schulz (talk) 14:49, 17 December 2009 (UTC)
• (EC) For completeness: You can transform one into the other through v=lambda * f ([phase]speed = wavelength times frequency). For EM-radiation, the speed is fixed at lightspeed. And the reason why different things (sound, radiation, all things that rotate on an axle) are all described using hertz is that they all are, on some level, the same: A circular process which repeats, so you can count how often it repeats in one second, giving you the hertz value. --TheMaster17 (talk) 15:01, 17 December 2009 (UTC)

So basically then, you can convert anything that happens every once in a while to hertz? So you can say something like, "my birthday is 3.16887646 * 10^(-8) hertz". Doesn't this get confusing?--72.178.133.37 (talk) 15:02, 17 December 2009 (UTC)

You can, and yes, it's often completely impractical (as is the Google example that started this). However, odd units and transformations can be useful teaching tools -- you may want to look at the firkin-furlong-fortnight unit system, a system of measurement that exists for little purpose except geek humor. — Lomn 15:08, 17 December 2009 (UTC)

Although as a somewhat-pedantic note, "every once in a while" is subject to interpretation. Hertz values are most commonly used for things that cycle regularly, without significant variation. Expressing the "hertz of New York Yankees championships" wouldn't have much meaning, because the time between each is variable and not dependent on the other values. Google's use of "blue moon" is something of a middle ground -- the true time between blue moons is variable (thus the value they give in hertz is an approximation), but it's also predictable. — Lomn 15:13, 17 December 2009 (UTC)

In fact, there are two SI units that are both "1 per second" or 1/s. The hertz is intended for regularly repeating events, like the frequency of a wave, while the becquerel is for radioactive decays, which occur randomly but whose expected rate is predictable. --Anonymous, 21:57 UTC, December 17, 2009.

I'm reminded of this [[6]]. Truthforitsownsake (talk) 00:36, 18 December 2009 (UTC)

Wormholes and Blackholes

What is the difference between wormholes and blackholes? --Reticuli88 (talk) 14:55, 17 December 2009 (UTC)

Wormhole v. Black hole. First sentence of each should clear it up. --Mr.98 (talk) 15:10, 17 December 2009 (UTC)

If I had a choice, I'd prefer to go thorough a wormhole then a black hole. At least I think so. Obviously once I get thorough the wormhole and find some aliens with anal probes I reserve the right to change my mind Nil Einne (talk) 17:08, 17 December 2009 (UTC)

Well, it is not even theoretically possible to go "through" a black hole. Think well instead of tunnel. Googlemeister (talk) 17:12, 17 December 2009 (UTC)

Was wondering how long it would be before someone said something like that Nil Einne (talk) 18:42, 17 December 2009 (UTC)

Collective Human Mind Connection to the planets Ecosystem

Awhile back I remember reading a wikipage on some Theory on the entire human population mind(s) being connected on some unnamed level with the Earths Ecosystem. Does anyone recall what this Theory is called? Cheers, --i am the kwisatz haderach (talk) 17:09, 17 December 2009 (UTC)

Sounds a bit like James Lovelock's Gaia theory. --TammyMoet (talk) 17:15, 17 December 2009 (UTC)

Specifically, his Gaia hypothesis.--Shantavira|^{feed me} 17:17, 17 December 2009 (UTC)

That was it. Thanks much. --i am the kwisatz haderach (talk) 17:24, 17 December 2009 (UTC)

Sorry, but I beg to differ. While science-fictional extensions to it might have been made, Lovelock's Gaia hypothesis itself does not assume any supposed human group mind, it merely posits that the Earth either behaves somewhat 'like' a single living organism due to biosphere-atmosphere-hydrosphere-lithosphere interactions (the 'weak' form), or that by the usual definitions of life, it 'is' a living organism (the 'strong' form). —Preceding unsigned comment added by 87.81.230.195 (talk) 16:36, 18 December 2009 (UTC)

Is a hot radiator disrupting my TV's remote control?

I have a tv near to and somewhat facing a hot radiator. Could this be disrupting the infra-red signal from the remote control? The standby light sometimes starts flashing and the tv won't start - I'm wondering if this might be the cause. Thanks. 84.13.35.30 (talk) 18:00, 17 December 2009 (UTC)

It's very unlikely. Infrared diodes usually send signals modulated by a digital code, so it would be difficult for a steady IR source (even if it radiates at the same wavelength) to interfere. If the emitted IR signal from the radiator is very strong, it might be plausible that it's saturating the receiver diode's front end amplifier, but this again seems unlikely. Nimur (talk) 18:06, 17 December 2009 (UTC)

Extremely unlikely. The IR used by a TV remote is about 900nm, which is only emitted (as thermal radiation) in considerable quantities by something over maybe 500°C (900nm is only slightly longer than the 700-750nm limit of the visible spectrum, so it needs to be almost red hot). Your radiator won't be anywhere near that hot. An incandescent light bulb will emit far more at that wavelength than your radiator ever could, and TV remotes work fine in rooms light by incandescent bulbs. --Tango (talk) 19:01, 17 December 2009 (UTC)

I propose an experiment. You may be interested to know that you can use the camera in your cellphone (assuming you have one) to actually SEE the infrared light coming out of the TV remote. Cheap cellphone cameras don't have infrared filters - so they see IR light at the frequencies that TV remotes use. Most buttons on the TV remote send a brief flash - but if you hold down the volume up or down button, you should get either a solid light or a fast flashing light. This lets you be sure that the batteries aren't dead (or put in backwards or something). Now - you can sit with your camera where the TV's sensor is (do it at night with the room lights off) and you'll be able too see if there is something else interfering with the signal. What you WON'T see is the radiator glowing because of the heat! But maybe there are confusing reflections bouncing off the shiney paint on the radiator? You'll see what the TV's sensor sees - which is really kinda cool! SteveBaker (talk) 01:16, 18 December 2009 (UTC)

I do not have a cellphone, but the remote has a visible light that flashes when I press a button, so I assume its working. 89.243.91.31 (talk) 21:02, 18 December 2009 (UTC)

silicone or rubber compound used for grips etc...

I am working on a new fly fishing tool that requires a very soft rubber grip (possibly translucent) I have only seen it on a hairbrush handle and nothing else. It like nothing I have ever seen before. Doeas anyone know what type of material this is or what it is called.? It is somewhat clear,very soft , no memory any help would be appreciated greatly thanks Jason ,pennsylvania —Preceding unsigned comment added by 24.229.199.70 (talk) 18:09, 17 December 2009 (UTC)

It's going to be hard to tell - but if I had to guess: Gel pads are usually made of a Polyurethane-based elastomer...these grips sound kinda similar to a gel pad. SteveBaker (talk) 19:52, 17 December 2009 (UTC)

following migration routes leading to discovery

Now-a-days hunters still wait along migration routes waiting for the opportunity to kill. Before the gun this was possibly done with bow and arrow or snares where flock were know to land. Even crocs take advantage of the knowledge of migration. Is it possible that the discovery of Greenland came form the following of the Barnicle Goose from Western Europe to Greenland over time of seeing it fly in that direction far out at sea? 71.100.0.206 (talk) 19:54, 17 December 2009 (UTC)

The discovery of Greenland by whom? Greenland has been settled by various people at various times. The Saqqaq culture settled Greenland in about 2500 BC, and left no written history; near as I can tell, it is unknown why they ended up there, or even where they came from. The European settling of Greenland came in the 10th century by way of the Vikings, doing pretty much what Vikings always did, which is to ride around in boats and find stuff to take. I don't think that there is any evidence that the Viking settlement of Greenland was as a result of following bird migrations. --Jayron32 20:11, 17 December 2009 (UTC)

Isn't there still controversy over who discovered America or has that been resolved?. American Indians were living on the continent long before Europeans arrived. ... of course I mean by Europeans. 71.100.0.206 (talk) 20:35, 17 December 2009 (UTC)

There's a notion sometimes called the Columbus principle, which states that it's not who discovers something first that counts, but who discovers it last. It's counterintuitive at first blush, but if you think about it, it's actually fair. If you discover something, but then don't succeed in causing knowledge of it to be preserved, what did you accomplish in the long run?

This is orthogonal to the point about the Americas already being inhabited at the time. From their point of view, of course none of the European explorers "discovered" anything; they already knew about it. But there was no way for that knowledge to be transmitted to Europe, so from the European point of view, it was a genuine discovery. There is no contradiction between these two things. --Trovatore (talk) 23:55, 17 December 2009 (UTC)

I happen to be reading The Route To India, A Journal Of The First Voyage Of Vasco De Gama in 1497-9, written at the time, and it is very clear from that that when going around the east coast of Africa, rather than sailing along a dark continent, the area was in fact busy and vibrant with Arab and Indian traders who had already been to India and to the Mediteranean as well. When they reached India, the explorers were surprised that the first person to come on board their ship could speak fluent Portugese. They also met two unnamed traders from Tunis who spoke european languages, so they were earlier explorers. 89.241.43.33 (talk) 12:20, 18 December 2009 (UTC)

In that regard now that I think about it I suppose a discovery of Greenland from trying to figure out where Barnacle Geese were headed if not put in a journal or made part of a story or persevered in some other way would then kill the discovery and the reason for it. Perhaps such a story has been overlooked if in fact it was preserved and what needs to be done now is to find it. 71.100.0.206 (talk) 00:27, 18 December 2009 (UTC)

We already have such a story: how Gunnbjörn Ulfsson was blown off course and spotted some islands. See History of Greenland, Saga of the Greenlanders and Erik the Red's Saga. 75.41.110.200 (talk) 02:08, 18 December 2009 (UTC)

You know, I'm guessing here but if I were a bird flying to Greenland from Western Europe and I flew over Iceland, that is where I might stop to have a few veggies and a good night's rest. 71.100.0.206 (talk) 04:31, 18 December 2009 (UTC)

Greenland was discovered after Iceland. In fact, Iceland was already settled to some extant. Googlemeister (talk) 14:44, 18 December 2009 (UTC)

Ice in My Freezer "Sublimates". Why?

If I make ice-cubes in the freezer on my refrigerator, the water becomes ice well enough, but after about a months time, I'm only left with slivers of ice at the bottom of the tray. I don't know if the ice is necessarily "sublimating" as I doubt that I'm getting steam in my freezer, but might the ice be going directly to water vapor? If so, why? All other freezers I've had required de-icing while mine isn't capable of keeping ice. Zhatt 22:00, 17 December 2009 (UTC)

Hmm, hard to say. Did you recently move to a drier climate or something? As a practical matter, though, I can't see it as very important; month-old ice tastes terrible (assuming you have anything other than ice in your fridge), and you should throw it out anyway.

Just by the bye, the verb is usually sublime rather than sublimate. Sublimating is something you do with psychological impulses that you can't admit to yourself oops, I think I got that wrong -- that's repression. You repress desires you can't admit; you sublimate the ones you can't satisfy. Or something like that.. --Trovatore (talk) 22:06, 17 December 2009 (UTC)

I don't know if it is technically sublimating, but it could be melting and then evaporating. Do you have a thermometer in your freezer (or can you put one there)? You may find it isn't really cold enough. If it is only just below 0°C then it will be very close to the triple point of water. That means water can very easily change between all three common states of matter. The water is always in a dynamic equilibrium, meaning there is always some bits melting, some bits freezing, some bits evaporating and some bits condensing. There should be the same amounts doing each so the total amounts of ice, liquid water and water vapour should stay the same but since your freezer doesn't ice up that probably means it has some kind of dehumidifier, so the bits that evaporate disappear off so there isn't much water vapour there to condense. That means the equilibrium is broken and the water gradually disappears as more bits melt, then evaporate and then get sucked up by the dehumidifier (which will then condense the water and collect it somewhere where it can evaporate out into the air outside the fridge). If you can get the freezer colder, that should reduce the amount of evaporation going on. It should be at least -10°C, probably colder (I can't remember the exact guidelines). --Tango (talk) 22:18, 17 December 2009 (UTC)

You don't know if it's technically subliming. --Trovatore (talk) 22:35, 17 December 2009 (UTC)

Yeah... I should have taken the hint when I edit conflicted with you and corrected my spelling... --Tango (talk) 22:56, 17 December 2009 (UTC)

Actually Wiktionary seems to think they're both acceptable. Subliming is just what I've heard, and I do like that it's a different word from the psych one. --Trovatore (talk) 22:59, 17 December 2009 (UTC)

Never heard of the triple point, but that sounds like a likely situation. I'll grab a thermostat on the way home and check it out. I'll report back here if I find out anything. Zhatt 23:04, 17 December 2009 (UTC)

Commonly in the UK snow disappears with the temp well below freezing. I don't know why you should be adverse to labelling it sublimation.--BozMo talk 23:11, 17 December 2009 (UTC)

The noun is sublimation, the verb is sublime. --Trovatore (talk) 23:15, 17 December 2009 (UTC)

I wonder if this could be a pondial thing, like orient/orientate? --Trovatore (talk) 23:16, 17 December 2009 (UTC)

If I'm reading the sublimation article correctly, it seems that sublimation occurs at the triple point. So it would be safe to say that its subliming if what Trovatore described is what is happening. Thing is, on the water article it notes that while the triple point of water is nearly at the freezing point, the triple point is also at a pressure about 1⁄166 of normal sea level pressure. I don't think my freezer is also a decompression chamber. Nor is it on Mars. Zhatt 23:35, 17 December 2009 (UTC)

The triple point is where the partial pressure of water vapour is below 1/166 atm, the total pressure can be far more. --Tango (talk) 17:49, 18 December 2009 (UTC)

The simple answer is I bet you just have a freezer with auto-defrost, in australia we call it "frost free". I'm surprised no one has mentioned it already, it has been very common in freezers for years. Vespine (talk) 00:00, 18 December 2009 (UTC)

The process is really no different from evaporation. Even though the ice is a solid - the molecules are still jiggling around (as they will anytime the temperature is above absolute zero) - and once in a while, one is going to get knocked out of position and go flying off someplace else. The air inside a freezer is very dry indeed - so the odds of any stray water falling back onto the ice is vastly less than any from the ice ending up elsewhere - so slowly but surely, the ice-cubes get smaller. Now - whether it's subiming or sublimation or evaporation or some other thing is purely a matter of vocabulary. The effect is that the water goes from ice to vapor without ever having been a liquid in between - while being at a temperature below it's melting or boiling point. But that's not really the same as the way that (for example) dry ice goes straight to CO2 gas when it warms above it's melting/boiling point. The underlying mechanism is the same - but it's a matter of degree. In humid sub-zero air, the ice would gain volume as fast as it loses it - but the dry ice is hitting it's boiling point and it's going away, no matter how much CO2 gas is mixed into the air. SteveBaker (talk) 00:47, 18 December 2009 (UTC)

SteveBaker is right. Ice sublimes perfectly fine at temperatures well below the freezing point (the triple point is irrelevent, since your freezer is not anywhere near the correct pressure to be at the triple point). Inside of a block of ice, molecules are vibrating at multiple speeds; some are vibrating fast enough to overcome the lattice energy of the ice. Doing so means they seperate from all of the other molecules around them... They become a gas. Its exactly the same as a liquid evaporating. There is no functional difference between a solid and a liquid in these events. Lots of other solids are as volatile as ice; some much more so. Naphthalene for example is a solid at room temperature, and sublimes even more readily than does ice. --Jayron32 03:13, 18 December 2009 (UTC)

Refrigerators and freezers are extremely dry. They have almost no humidity at all. So ice can evaporate very easily. Water will evaporate at temperatures well below boiling. The lower the humidity, the faster water evaporates. In a freezer (and fridge, since they are connected), the humidity is so low, ice will evaporate. See here [7] - it seems that ice will evaporate down to about -12c/8f and most freezers are kept warmer than that. But note that the freezer coils ARE colder than that. So the ice evaporates, and then condenses on the freezer coils - this keeps the humidity of the air in the freezer very low. Ariel. (talk) 08:24, 18 December 2009 (UTC)

Jello

Does Jello still have horse hooves in it? --71.144.122.81 (talk) 23:49, 17 December 2009 (UTC)

Our Gelatin article says: Gelatin (from French gélatine) is a translucent, colorless, odorless, brittle, nearly tasteless solid substance, derived from the collagen inside animals' skin and bones. Comet Tuttle (talk) 23:52, 17 December 2009 (UTC)

So they don't have any way to make it synthetically? --71.144.122.81 (talk) 00:04, 18 December 2009 (UTC)

Make what synthetically, horse hooves? hydnjo (talk) 00:19, 18 December 2009 (UTC)

Collagen. It's just a chemical compound, so there must be some reaction or series of reactions which can produce it. --71.144.122.81 (talk) 00:21, 18 December 2009 (UTC)

Yes - but perhaps not economically. SteveBaker (talk) 00:36, 18 December 2009 (UTC)

There are a number of Ghits for "vegetarian jello" though... Dismas|^(talk) 01:10, 18 December 2009 (UTC)

But these are usually based on agar-agar (seaweed-derived), guar gum (guar bean-derived) or other such polysaccharides, rather than synthetically produced gelatin. -- 128.104.112.87 (talk) 16:01, 18 December 2009 (UTC)

People in the English-speaking world tend to get somewhat irrational when it comes to horses in food - but I very much doubt that horse hooves are actually available in sufficient numbers to met the vast amount of jello that's produced. Complying with food safety standards with horses would also be a nightmare because they aren't farmed commercially for the purpose. Cow hooves and skin are just as applicable. These are waste products that are presumably cheap and in plentiful supply - they would likely be wasted if we didn't use them for stuff like this. So I would be very surprised to hear that horse hooves are actually used for making Jello. Cow hooves is much more likely - maybe pig trotters - who-knows-what bits of chickens and turkeys. SteveBaker (talk) 01:49, 18 December 2009 (UTC)

Actually, its a Good Thing!!! that Jello and products like it use animal hooves and other waste products in their production. One of the "criticisms" of meat consumption is that it is wasteful; not all parts of the animal get used. Its applications like Jello (and Glue, and other uses) which help to ensure the efficiency of the system. Its using every part of the animal, which can't be bad, unless you object to eating animals because they have have more biological rights than do plants... --Jayron32 03:07, 18 December 2009 (UTC)

Or if you don't want to eat stuff made from hoof and skin, a great substitute little known in the west but very common in Asia is agar. Mind you some people might find the idea of seaweed just as unappetising as hoof but let me assure you it is quite tasteless and you can flavour it however you like. I personally think it's much nicer then jelly, it sets a bit firmer which i like, it's not as "sloppy", but it is still unmistakably jelly "like". I've learned a recipe for coconut jelly and it is a really impressive but simple dessert to make. I don't see why you couldn't use more traditional western flavours. Vespine (talk) 04:49, 18 December 2009 (UTC)

I would say agar is fairly well known in the west among biological scientists (and there must be quite a few on the RDS). I agree with you it's not commonly used for deserts though. I made a post a while back which discussed some issues relating to this a bit Wikipedia:Reference desk/Archives/Humanities/2009 November 11#Gelatin, whey, and lard vs. Islam. A key point which I raised there of relevance here is that a fair amount of the gelatine comes from pig parts. Take a look at the gelatine article. Cow/Beef/Bovine gelatine is also quite common although that may be used for halal products and sold to Muslim countries (however there's some dispute over whether the cows need to be slaughtered in a Dhabīḥah ḥalāl fashion) and perhaps for Kosher gelatine (again the cows may have to be slaughtered in a Kosher fashion and it's possible fish gelatine is more common for that purpose). In particular I suspect if the gelatine doesn't say it's more likely to be pig/porcine then cow/bovine/beef although it could be both and vary. There are ways to identify it [8]. I agree horse gelatine is only a tiny proportion of the world's supply if anything. Incidentally back to the agar-agar point, as you say deserts made from it are a lot firmer. I personally like both. Even in Malaysia, with gelatine jellies are quite uncommon gelatine may still be used in sweets, Western influence desserts and other food products and there is increasing interest in halal gelatine which I think highlights the fact there's no simple substitute. Of course that makes problems for Hindu consumers since the halal gelatine is usually cow/bovine/beef. Fish gelatine is also on the rise I believe with new methods of production being researched (seems to be of interest to Thai reseachers in particular) which will likely fulfill the needs of both Hindu, Muslim and Jewish consumers but not vegetarians ones of course. Nil Einne (talk) 06:04, 18 December 2009 (UTC)