My friend Nick Bilton has a good question. If you have an answer, please post in the comments.
Q. What natural food, other than eggs, turns from a liquid to solid, when heated?
The question only pertains to a natural food, no additional things added (so no water and sugar). Just a simple, single food. I've asked so many people and no one has an answer. I even asked friends at The Food Network and nothing. Joel's been trying to find out too and he's lost. Got any insight into this or know anyone that might? A lot of people have said blood, but that just evaporates and then changes, it doesn't actually change consistency.
RSS Feed
blood
(you have to cook it realllll sloowww)
Milk?
Blood in blood sausages & blood cube soup.
Define "Natural".
I would like to second the notion of milk as this substance. Please refer to yogurt and cheese.
Cheese & tofu could also be in this category. However, there is a chemical process to solidify some of proteins inside milk & soy bean juice prior to heating.
Squid ink does nearly the same thing as blood when heated. It curdles more, though. While working at an Italian restaurant I had to harvest squid ink to flavor and color risottos and pasta. We decided to see if it could be reduced and concentrated with the curdled results I mentioned. That was on a low slow heat. I'm pretty certain it would have been more dramatic and solid if the heat had been higher.
Cheese and yogurt all require some sort of chemical addition to become solid. Milk only curdles when heated.
The correct term for the process is Denaturation.
Eggs, and the film that forms when milk is cooked are listed as examples in the Wikipedia entry.
Cake/pancake/muffin batter is liquid until it's cooked.
Adding flour to water then baking it turns it from soft fluffy powder, to liquidy soup, to hard as brick lumps of inedible dough.
Add cornstarch to water and it turns solid just by kinetic energy.
Honey is liquid but will harden to a crystalline lattice of sugar if heated and allowed to evaporate.
Jell-o: Gelatin comes from horses (ewww...)
http://en.wikipedia.org/wiki/Gelatin_dessert
maple syrup or maple sap
Jello
#12 Cornstarch and water is called a Newtonian Fluid.
Anything with a significant amount of protein will do this.
Cream.
Honey. I have a bunch of honey in my cabinets that has crystallized.
Mekki is right. Almost any sufficiently protein-rich mixture solidifies when heated.
So, depending on your definition of 'food', I'd like to nominate a candidate: Semen.
Hey, it's as natural as it comes. Natural and man-made.
i'm pretty certain semen behaves almost identically to egg whites.
There are three words in english language that end in "gry" two are "angry" and "hungry".
What it is the third?
Damn ...spazzm beat me to it by 20 seconds.
I guess spazzm gets to eat the ooky cookie.
Unicorn semen.
tree sap
Since semen has already been suggested I'll have to go with my second choice: cement.
I've got it! Maple syrup.
Mmm, maple sugar candy is delicious. :-)
Gah! And MrFitz beat me (sorta) by one minute. :-/
Heavy cream (no I don't mean semen) won't curdle from being heated, but if you boil it and boil it, it thickens almost arbitrarily. If you sweeten it a little (and maybe put in a little vanilla), you can scorch it a sort of like egg. The result is delicious!
Aren't crab and lobster meat liquid before cooking them?
Not to mention blood is more of a supernatural food.
open a fresh one sometime
@nehpets:
According to the 1933 edition of the Oxford English Dictionary:
aggry Gagry Agry ahungry gonagry magry gry malgry anhungry haegry Badagry managry Shchigry Ballingry hangry mannagry shiggry begry Margry Shtchigry bewgry maugry boroughmongry higry pigry mawgry skugry bowgry hogry meagry Sygry braggry hogrymogry Tangry Bugry hongry menagry Tchangry Chockpugry messagry Tchigry Cogry houngry cony-gry huggrymuggry nangry th'angry conyngry overangry cottagry Hungry Bungry Pelegry Tingry Croftangry hwngry Pingry toggry iggry Podagry ulgry Jagry Pongry unangry pottingry vergry Dshagry kaingry Vigry Dzagry vngry Langry puggry Echanuggry pugry Wigry Egry ledderhungry rungry Lisnagry scavengry fenegry losengry Schtschigry Ymagry
Now if you had said three words in "THE english language"...
#22: I'm bored, so I'm going to say the third word is ... "language". :)
#29: No, not exactly liquid. I guess you watched Cast Away, right? :)
Oops, that should be #21, not #22 ... although the poster is the same :)
What about crab meat? In raw form it seems similar to a liquid. Recall the mess Tom Hanks made in Castaway?
D'oh. Beat me to the punch.
Saying eggs go from liquid and solid is not entirely correct -- the dissolved proteins (which would be solid with the water removed) denature and link together, trapping any un-evaporated liquid in a mesh and eventually squeezing them out if heated too much.
It's the exact same process as making Indian sweets out of milk, blood pudding out of blood, or, indeed, just cooking your average everyday meat.
you people who have never met a crab; dive a few meters in clean water,pick one off the bottom, surface, break off a claw,, split with teeth and enjoy the firm, sweet texture. Don't get nipped and do float otter style while you dine. I suppose land crabs are hideous, never tried those.
True, but you can see a small scale version of that process fairly quickly - some of the proteins in cream will form a skin, which is the protein turning into a solid. When you bake a fish the eyeball liquid (the aqueous humour) turns solid. Not all proteins turn solid, though - collagen is a protein but if cooked very slowly as in stewing,it converts to gelatin. Anyway, yeah, lots of proteins do turn solid when sufficiently heated. It's one of the reasons that blood & marrow are effective thickeners in soups.
#7 - tofu is actually solid because of coagulation then compression, not heating.
Eyes? they solidify when heated.
As a guy that recently left half a carton out all day, on a day when the temperature soared into the triple digits (F), I can confirm:
Milk turns from liquid to solid when heated.
Also: Ew.
A lot of people have said blood, but that just evaporates and then changes, it doesn't actually change consistency.
I don't think that's true. Meat goes from soggy to firm when cooked, but the clincher is you can use blood to thicken sauces. Squid ink is also a good one.
So I'm with #10. I'm sure there are other kinds of animal gunk that do the same thing.
Gelatin (and I'm guessing agar and caragheen) involve additives and use heat to dissolve rather than solidify. Yoghurt etc are basically about gently adding and acid to the milk and cheese removes the liquid (but the skin on top might be a different matter). With the maple candy I'm guessing that's evaporation.
I think proteins (like blood) do thicken when heated, but I agree that for proteins to become a solid, either another element needs to added (like acid for mozzarella or paneer) or the liquid has to evaporate - so that's out. Everything else mentioned is either not a liquid (like gelatin) or requires another element or process. So for something edible that changes from liquid to solid using only heat, without adding another ingredient or process and without evaporation, I think the egg stands alone.
As has already been said, Black Pudding transforms from liquid to solid when heated.
Some of the more atlanticly-challenged amongst you should wiki it.
that liquid that oozes out of thawed meat
Since we're all nerds here ;) I should point out that #16 is wrong, #12 corn starch and water is a NON-Newtonian fluid
http://en.wikipedia.org/wiki/Non-Newtonian_fluid
(wikipedia)
The interior of tomatoes turns pretty solid when boiled. I haven't seen what happens if they're left to cool, though - I usually go straight to mashing them when they burst out of the skin.
I agree with #11. Pancake batter is a fairly goopy liquid when first made, but it only takes a few seconds on the griddle before they're converted into golden discs of God's Love.
Well obviously it's a liquid solution containing α-cyclodextrine (αCD), water and 4-methylpyridine (4MP).
This was covered on slashdot in 2004 for pete's sake.
Gluten. Proteins in general.
When people are saying "blood", "milk", and so forth, they are referring to the denaturing process of proteins in which they uncurl and interlock. First, that turns them into a network which acts as a solid. Second, after a bit, the denaturing and interlocking proteins can begin to squeeze out water.
Looking through chapter 15 of McGee, I'd suggest that solutions of starches are another possible answer to the question -- these would include things like cream-of-wheat. A mixture of starch-rich-grains, such as cream of wheat, rolled oats, or rice, and water will be a fluid -- basically dirty water. Then, "When starchy plant tissue is cooked in water, the granules absorb water, swell, and releach starch molecules; when cooled again, the startch molecules rebond to each other and can form a moist but solid gel." Which would be a description, for instance, of polenta.
However, the "solidification" process, at least with cream of wheat in some concentrations, actually starts before the cooling.
Other heat-activated carbohydrates include pectin and other hemocelluloses, but those might be a bit of a stretch. Plant gums such as agar and alginates are also heat-activated and can grab and lock away water forming a hydrocolloid gel.
But the basic answer is "proteins". Protein denaturation and coagulation. Page 808 in McGee goes over some of the basics. Of course, eggs are one obvious example, but, as pointed out by other commentators, blood and milk are also examples.
And I'd say that gelatin is another. It activates when heated -- it then needs to be cooled again to get it below its melting point, but, with care and some additives, it might be possible to lower the activation point, and/or raise the melting point, to the point that they overlap.
And, of course, gluten.
A cake batter would be another example of a substance that turns from liquid to solid when heated. And, of course, eggs can be a part of that, but if you've ever done vegan baking, you know that it CAN be done WITHOUT animal-sourced proteins. It's not as easy, but you CAN get that process to work with only plant-based glutenoid proteins.
Ditto to the wise folks who talked of coagulating proteins out of solution. Despite what the OP says, cooking blood is undergoing pretty much the same reaction as cooking egg; blood just has more water to lose. Tangentally, it's not quite the same as clotting blood; that relies on enzymatic activity to make platelets "sticky", which leads to a similar protein cross-linking as cooking. But because human enzymes only work within a narrow temperature range, it isn't responsible for the cooking reaction.
While not strictly a food, I vote for tree sap. Especially if it's from a rubber tree.
@17 - Nope, you mean a non-newtonian fluid.
@21 - I only came across that riddle recently and am completely baffled by it. I read it as meaning:
There are three words in [the] english language that end in "gry". Two of these three words are "angry" and "hungry". What is the third such word?
But the answer seems to suggest I should read it as:
There are three words in "[the] english language" ... what is the third?
So to solve it one has to assume, based on absolutely no evidence, that half of the setup is a lie. Am I mising something here, or does this "riddle" really suck this badly?
...I bet you're right about the semen though. Hmm, this reminds me of the conversation we had about plasticising milk/semen protein the other day; egg whites would work beautifully.
As I am a food technologist, please excuse me for sounding authoritative.
what you are really looking for is a food that is naturally high in either starch or protein, without adding extra water to activate the starches.
the change from milk to yogurt should count. You can take a glass of fresh milk, let it sit at 100 degrees for 8-12 hours and you will have a considerably more viscous substance. This is really more of an acid digestion of protein than a change due to heat, the heat you apply just helps nurture the bacteria. Ditto for tofu and other cheeses.
I have no empirical evidence, but from what I understand about the composition of semen, it probably wouldn't gel the way an egg would, protein count is much, much lower.
The philistines who count raw crab meat and shrimp as a liquid are on to something since seafood is a very wet, very high protein substance. You could probably puree the wettest organs in a fish, or puree an oyster and the result would be a very runny liquid slurry, which would then solidify when heated. I have never made a seafood mousse, but I assume this is the principle behind the thing.
Shake those molecules thermally until some of the bigger ones curl up in a delicious way...nom nom nom
Check what Harold McGee (who wrote about this on page 808 of the latest edition of "on food & cooking" and is totally my homegirl) has to say!
What you're talking about is caused by denaturation, but it is more specifically protein coagulation which is one of "several consequences of denaturation that follow for most food proteins."
it's the same thing going on in the egg or the blood or the milk as is going on in any other protein as it is denatured by "exposing [it] to heat, or to high acidity, or to air bubbles, or to a combination of these." But, since they're liquids to start, they form a network of scrambled-together proteins that give it a structure. I guess technically it's then a gel. (right? semisolid colloid and all that?) At any rate, if you continue to denature (by overcooking) blood or eggs or milk you end up with curds and a liquid.
Hagfish slime. I remember watching a video of some marine biology students making an "egg white" omelette out of the stuff.
It was kind of gross.
# 51 I stand corrected :-)
balsamic vinegar
A can of sweetened condensed milk, unopened, set in a pan to boil for an hour or so, turns into deliciously firm and wobbly dulce de lecce.
Konnyaku, The Vegan alternative to gelatin. Although it is sort of more like a gel to begin with, but after it's cooked is very firm.
Sweets such as caramel and toffee
Weasel fingers. All other answers are wrong
Bird's nest starts off as liquid
From a biological sciences standpoint: eggs become solid because the proteins (primarily albumin) denature (that is unfold) and then stick together in long sticky strings.
As far as this question goes it is completely open ended. There are a multitude of things that become solid when heated.
The blood example is not just evaporation it also undergoes denaturation similar to eggs. The same is true of the curdling that happens in any dairy products.
Jello is a bad example because it is heated to go into solution and then cooled to solidify. Gelatin is also not made from horse hooves anymore. It is made from leftover porcine parts such as ligament.
Really pretty much anything organic (in the chemical sense) solidifies if heated properly... ever burn liquids?
I am assuming he means some substance that is like an egg and turns solid without burning?
yes i am dyslectix, and routinely leave out words.
but actually i did write the riddle wrong on purpose for the shear pleasure of seeing
aggry Gagry Agry ahungry gonagry magry gry malgry anhungry haegry Badagry managry Shchigry Ballingry hangry mannagry shiggry begry Margry Shtchigry bewgry maugry boroughmongry higry pigry mawgry skugry bowgry hogry meagry Sygry braggry hogrymogry Tangry Bugry hongry menagry Tchangry Chockpugry messagry Tchigry Cogry houngry cony-gry huggrymuggry nangry th'angry conyngry overangry cottagry Hungry Bungry Pelegry Tingry Croftangry hwngry Pingry toggry iggry Podagry ulgry Jagry Pongry unangry pottingry vergry Dshagry kaingry Vigry Dzagry vngry Langry puggry Echanuggry pugry Wigry Egry ledderhungry rungry Lisnagry scavengry fenegry losengry Schtschigry Ymagry
I will also note that pancakes (in the U.S. at least) tend to include eggs and thus aren't really an additional answer.
Did anyone else play the game of adding a small spoonful of baking soda to a cupful of elmers white glue?
It starts sweating profusely, smelling like cheese, and in a few hours solidifies into a surprisingly durable water proof plastic like material.
at least that's what it did in the 80's...
How about we do foods that turn from solid to liquid when heated? There are lots of those.
hogrymogry solidifies when heated too
ketchup.
is "tissotropico" (sorry i don't know the eng. term)
Methylcellulose is what came to mind immediately for me, although probably not what Nick probably means by a "natural" food. It is, however, not all that unnatural since it is derived from plant cellulose. Also, unlike eggs, methylcellulose's gelification is reversible - your product will "melt" in the refrigerator/freezer.
Speaking of egg oddities though, egg whites are one of very few foods we eat that are alkaline. From Harold McGee's On Food and Cooking: "On the pH scale, the yolk rises from a slightly acidic pH of 6.0 to a nearly neutral 6.6, while the albumen goes from a somewhat alkaline 7.7 to a very alkaline 9.2 and sometimes higher."
RE#49
and the liquid solution containing α-cyclodextrine (αCD), water and 4-methylpyridine (4MP).
http://physicsworld.com/cws/article/news/20325
I foresee a variant of this substance becoming a party drug.
12 hours of perfect bliss with no hangover.
But you MUST keep your body artificially cooled to 97 degrees for the duration.
If your temperature rises before the drug is fully cleared from your body, you are instantly ready join Gunther von Hagens's traveling exhibit.
This comment thread is a serious testament to people's inability to read and follow directions.
Latente, I think the English word you're looking for is "thixotropic": http://en.wikipedia.org/wiki/Thixotropy
you mean by your not contributing a food?
children's TEARS.
Sugar based syrups and caramel. Heat over a stove and they will thicken and harden.
Agar.
@ 5000!:
Agreed. So many of the answers here aren't a "simple, single food."
Cake batter, blood, and semen? C'mon.
oh? and what do YOU live on, Mr. Fancy Pants?
#70 For the win.
"hogrymogry" would make a great name for a band...
With sugar syrups, I discover Caramelization does take up some water, but I'm gonna maintain a lot of the thickening is just boiling water off.
For example, the 'hard ball stage' is when the syrup reaches a certain temperature, which it can only reach because the syrup has reaches a certain concentration (the boiling point rises the less water there is).
That said, what happens to condensed milk is probably more complex. Jams involve sugar concentration too but, as noted above, they are something else again.
Well we may never learn the answer, but I did find the definition to my new favorite word while looking:
This involves adding water so it's a little off topic - but I want to know why it works! If you add boiling water to tapioca starch it thickens really nicely and you can use it to make pão de queijo - taste brasilian cheese buns. If you try using tapioca starch like normal flour it just gets runny. Anyone know why?
Lobster. Have you ever broken open a live lobster's claw? Seeping, oozing, goo.
Wow, the vast majority of the comments for this entry are gross. That is sort of interesting in itself.
Regarding gry: the final word on this tedious little stumper belongs, as so many final words do, to Cecil Adams.
http://www.straightdope.com/classics/a3_251.html
I like the squid ink answer, sounds awesome.
The "birds nest" answer is awesome too, that's some sort of spider silk delicacy or something, no?
And just who is cooking their semen? ewww, but coool. Could you blog abut it, sans photos? I personally respect my sailors too much.
Pretty much every other answer above is a mix of ingredients, or just a matter of evaporation, and are therefore fail.
My best guess is a variation on the original question: fish roe.
has anyone tried heating hagfish slime?
This comment thread has turned into a solid.
Re semen. Now I'm so curious! ug!
Isn't raw crab meat somewhat liquid before cooked?
other then that, Jello gets cooked and cooled, but I assume has a similar reaction going on.
Batter of all kinds is sorta redundant because there are eggs in there that are doing most of the changing.
Sugar is the other option. Sugar water is cooked into marshmallows. That is the only reaction that seems similar to me
well, abalone is nice twitching
http://physicsworld.com/cws/article/news/20325
Now That is fun
Guar gum or psyllium husk? Or do they count as food even?
Sugar water and gelatin are solids dissolved in water, and therefore are not single ingredients.
Also, prepared gelatin (a.k.a Jell-o) is a colloid, not a solid.
Come to think of it, how about Gum Arabic.
Great minds think alike, Nehpetse.
marshmallows have starch. historically the starch of the marsh mallow.
i've had cocaine go from solid to liquid, but that's not the question is it?
it's not as if most of the posters in this thread actually read the question anyway.
we don't call it gum arabic anymore. go ahead try to find gum arabic in a list of ingredients. i'll wait...yes yes how about that gum arabic wonder stuff that it is.
Cream, (non-pasteurized) when churned, becomes butter...no additives, no heating, no nuthin'.
"Sugar water and gelatin are solids dissolved in water, and therefore are not single ingredients.
Also, prepared gelatin (a.k.a Jell-o) is a colloid, not a solid."
Doesn't sugar water exist in nature, couldn't you make little marshmallows out of nectar or something?
Are eggs ever a true solid?
@ #85: I prefer the last word on the subject from xkcd.
Giancarlo says vitreous fluid for sure, or maybe honey.
#17 wins.
My answer is Chicken Fat.
It's true you won't find "Gum Arabic" on many labels, but that's only because it's called "Gum Acacia" now. Something to do with the Sudan.
Even if it's not right, the stuff is just awesome (and is mostly responsible for the diet coke/mentos reaction, fwiw).
Someone may have already posted this, but, in a process that I cannot explain in scientific know-how, if you heat soy milk in an open pan, the top layer will begin to solidify, which can then be set aside to be eaten later as tofu skin.
What about eyeballs? I saw on Man vs. Wild, Bear ate a yak eye and liquid came out, but it looked like the sort of stuff that would solidify like egg whites if cooked.
Ill go for seitan.
Cooked until solid and typically used as a 'meat substitute' like tofu or tempeh. Formed from wheat gluten and other tasty nibbles...
babies ---> blender ---> 9x12 inch pan ---> oven 350 F ---> babyloaf
ANY food,liquid or solid, when cooked long enough or at sufficient heat, will turn to a solid.
Spätzle = southern German egg noodles, my wife still makes them herself - addictive stuff
http://en.wikipedia.org/wiki/Sp%C3%A4tzle
I've got it:
Popcorn!
The centre of the kernel is moisture and oil (according to Wikipedia) which solidifies when it comes into contact with surrounding air.
That is exactly why popcorn is so great, it is the only kind of food you explode before you eat it.
http://en.wikipedia.org/wiki/Popcorn
Er.
Based on empirical evidence, I can say that semen does not behave anything much like egg whites when heated. #52 is correct.
The story behind this is convoluted, involves the phrase "in the name of science!", and no, there is no way in hell I am ever blogging it.
Anything that's a mixture of a liquid and a solid where the solid melts at a higher temperature than the liquid evaporates would qualify.
For instance, cane juice, if you boil it long enough, will turn into cane sugar and water vapor.
cake batter.
sperm.
it's largely albumin, essentially the same thingas egg white, and therefore if poached, fried, or baked i have every reason to believe it would go white and hard.
it is also a definitely a foodstuff.
In addition to the very protein heavy foods listed above, there is a whole class of plant based foods that gel when heated due to pectin: think jellies and jams.
Jelly/Jam/Marmalade.
The original fruit might be solid, but it's the juices inside that turn into the jam, the pectin sets from exposure to heat and causes it to solidify.
I know this from brewing experience - if you want to add fruit, you can't get it too hot or you have to add an enzyme to cause the pectin to release.
Milk turns to cheese -- you can make this without rennet, I've done it.
Maple syrup turns to a hard sugar.
@ #90
Batter need not have eggs in it, as stated quite a few comments up. Vegan baking works just as well as the omni version, sans eggs.
And marshmallows have gelatin/agar/carrageenan in them.
Milk turns to cheese, but it needs help. It doesn't have to be rennet, but it has to be something - like acid.
Maple syrup doesn't turn into sugar, maple syrup is sugar and water, once the water is gone, the sugar remains. Nothing is converted.
You people are goddamn terrifying, but two different types of terrifying.
Type 1: Knows that cooking blood, semen, and hagfish slime causes them to thicken (and summons Baal'goroth, Lord of the Abyss Between the Stars)
Type 2: Prefers their seafood served Klingon style (alive and pissed off).
Of course, now that I've posted this, someone is going to post their recipe for a blood and semen pudding garnished with live shrimp.
#86 MDHatter
Birdsnest is actually swallows' saliva, which when hardened is a Asian delicacy. But technically I don't think it works even tho I suggested it. It hardens naturally, not by heat.
Hot dogs.
Cheese.
Corn.
Salamander.
Lamb fat.
What about bread? I am not sure if regular bread dough meets the definition of liquid (it flows very slowly) but pancake dough and cake batters are liquids.
BenGoldAcre 114: Yes, but it's better raw, fresh...shall we say "applied directly from tube"?
The Blow Leprechaun 118: Not quite. There's a carmelization process too. And that can lead to at least partial solidification even without driving off any water: for example, the dulce de leche mentioned above, though I would cook it slowly for four hours rather than quickly for one, is entirely in a sealed can, so no water is extracted; but white liquid condensed milk comes out of an unboiled can, and firm gelatinous tan-to-brown dulce de leche comes out of a boiled can. Has a completely different flavor, too.
I'm not sure what would happen if you boiled the condensed milk for, say, 12 or 16 hours instead of four. Pretty sure it would be inedible, but it might be truly solid.
However, none of these things is "a simple, single food," unsweetened and with no additives. I would argue that milk is, and if milk is, the other mammalian secretion we've been discussing must be too! But condensed milk is concentrated and sweetened, so it doesn't count.
I'm not sure what would happen if you poured blood into a hot oiled skillet. I do not intend to find out, though I'd be interested to know if someone's done that experiment.
Esnible 120: all doughs are combinations of different ingredients (in fact some contain egg), and thus not a "simple, single food" like egg.
Oysters turn from a liquid to a solid when cooked.
For the snickering folks suggesting "semen"...
Try googling for the phrase "Soft Roe".
Gluten doesn't really change from a liquid to a solid, WRONG - it's a protein and it gets stringier and tougher as it's kneeded, but does not change essentially.
However, the starches in corn, wheat, oats, rice, and other grains can be cooked into a paste that was once quite liquid to a more solid form. Ever hear of pudding? As the protein amylase breaks down the tightly coiled starch molecules the starches both break off into sugars and they branch out into larger in volume molecules, thickening the paste. Et voile, pudding! Of course, if you cook it longer the pudding loosed viscosity to become runnier again, as the amylase continues to break down the starches and the starches loosing the branches.
- Ethel
@ anonymous around 2:27. You're my hero.
Epicanis 129: Who's snickering? We're talking about one of our favorite foods!
couple things come to mind:
Juice from the Casava, the juice when cooked slowly form small egg like balls. used in puddings and the like:
Pectin, a geling agent, when heated to about 160F gels to make a soft solid... the base to jams and Jellies.. found in the juice of fruit rinds.
i know that coconut milk when cooked will gel as well, in to a soft paste...
People who say "sugar" are right--especially if they're thinking sap, as in the sap from the sugar maple tree. You heat that up for awhile and you get maple syrup. Keep heating and you end up with maple sugar.
A couple of decades ago, my girldfriend and I got some takeout from an Asian restaurant...I can't remember the exact country of origin. We ordered without really knowing what we were getting, and one of the dishes we ordered was crab legs. When my girlfriend and I broke them open, out poured a viscous tan-colored liquid. The legs were whole, so I doubt the meat was extracted and the goo injected somehow, but we were somewhat put off our food that evening.
Salt Water = Salt.
Most, if not all bivalve mollusks (mussels, oysters, scallops, clams) will solidify from a mucus-like consistency to solid when heated.
Also when lemon is added to them, where the citric acid "cooks" them.
Cornstarch. Mix it with water and it is a liquid, squeeze it and it is a solid.