Interesting thickening agents
I'm the kind of cook who wings it a lot, mostly based on experience, and I'm really interested in understanding the properties of ingredients.
You can almost categorize cuisines by the thickening agents they use. I've got a mental list of thickening agent that work, though I usually rely on the standards:
White flour-butter roux for French dishes
Cornstarch for Asian dishes
Beurre manee for stews
Then there are the things for particular dishes:
Flour-oil brown roux for gumbo
Cooked, pureed rice for bisque
Butter for rich sauces
Here are some that are open for discussion:
Coleman's Dry Mustard--I've found this to be an amazing thickener. Does anyone use it as such and for what?
Stale bread--Thinking of Italian soups and English bread sauce. Anyone have any novel uses?
Eggs--Not very adventurous here, beyond blanquette de veau, English baked puddings, and Hollandaise. Ideas?
Potato starch--open to ideas on this.
Nonfat dry milk--seems like it would work for something?
Tomato paste--Is it just my imagination, or does it thicken beyond the obvious original pastiness?
Peanut butter--Now this definitely thinkings exponentially from its original pastiness.
Chickpea flour -- applications as a thickener?
Any others, and what do you do with them? I there any way to get the shiny gelatinous quality of a real demi-glace by using another ingredient?
I suspect there's a wealth of information to plunder here.
Liverthink of giblet gravy.
Ground nuts and seeds. Frequently used in Mexican cooking, and Im sure elsewhere but nothing comes immediately to mind. West African, Im pretty sure (besides peanuts).
I think bread is used in every bread-baking cuisine.
Leeks (think of soup). Okra, well cooked.
Gelatin in various forms (a calfs foot in the stew).
File is powdered sassafras and it does indeed have a noticeable flavor. It is NEVER supposed to be used in gumbo that has okra in it, but that doesn't stop some people. To the best of my memory, when I was growing up in New Orleans, Seafood gumbo was thickened with file and other types (chicken and sausage, turkey, andouille) were thickened with okra. That's how my mom did it, and I do it, anyway.
Also, as per my mom's (and my) standard practice, giblet gravy is thickened with a nice dark roux. The liver is briefly cooked and added, chopped, just before serving.
Ground cashews are commonly used in Indian cooking as a thickener, and candlenuts used similarly in Malaysia, Indonesia etc. Lotus nuts/seeds occasionally also turn up doing that too, as do ginko nuts. European "sweet" chestnuts(the kind used to make "marrons glaces") have a very high percentage of starch, and were once so abundant, that they were used by the poor instead of cereal grains at times, ground into flour and used to make a kind of bread, starchy soups, etc.. But since blight destroyed some 4 billion trees in the early 20th century, they are now too rare and expensive to be used that way.
Water chestnuts(yes, those oval somewhat crispy slices in stir-frys), which are actually a type of tuber, are dried and ground into a flour/starch in China, and are considered a very delicate thickener for stir-fry sauces. The same applies to dried lotus root starch. I have used both, and indeed they do not contribute as gummy a texture as cornstarch can to the thickened liquid. I prefer water chestnut starch/"flour" to cornstarch for that reason. However, this "flour" can be hard to work with at first, as it comes in small firm/hard crumbly bits (do not confuse this substance with sweet chestnut flour). I guess it is not finely milled, once the starch is settled out of the pounded flesh and dried. At home, you should put it in a mortar and grind it into as fine a powder as you can, and then carefully dissolve it in cool liquid (give it a couple of minutes), before adding it to a hot wok.
Lucia, using water chestnut starch may be a way to get that "shiny" appearance to your demi-glace as it has a reputation for giving a sauce a nice, shiny appearance. Worth the effort IMO, but others may disagree.
There are many other thickeners from around the world with unique flavors and textures. I like to use tapioca starch myself a lot, along with water chestnut. I've used cashew butter in place of grinding a tablespoon of cashews myself with decent results in Indian recipes. I also recently enjoyed making a thickened savory yogurt soup that used besan(chickpea flour). I really enjoy experimenting with different thickeners. Last year I discovered using corn masa to make chocolate atole, a Mexican hot beverage that was yummy!
I've always been fond of starchy hot cereals like farina and gruel and congee, and thickened hot beverages. I encourage others to experiment in these comfort foods - you might be surprised how much fun you can have. Thanks Lucia for bringing up this topic!
Interesting question. I think you could break down the ones you have mentioned into starchy or gelatinous.
Flour is the thickening ingredient for basic sauces and gravies in homestyle american cooking as I learnt from my mother/joy of cooking school.
Either browned in a roux or just blended first with liquid and then added.
Cornstarch or Arrowroot for fruit pies, sauces, puddings, asian sauces.
Both of these also act as a coating and thickening ingredient when used to coat meats before searing and braising.
Potatoes in chowders, stews. And rice in these same uses.
Gelatious: Gelatin, agar agar and xanthan gum. Okra.
You mention mustard, which I think of as an emusifier. Also, I think the thickening effect of tomato paste is really reconstituting to tomato sauce, it is not a thickener in my mind.
Some thickeners, eggs, peanuts, break easily, is it the protein? which restricts how much more cooking you can do after they have been added. And File should never be reheated too....
And some dishes are thickened by more than one ingredient, ie pot roast, the gelatin from the bones, the starch from the browning flour, the potaoes or root vegies added...
You mention potato flakes. Here is an interesting technique I've used for almost twenty years as a replacement for roux.
Lets say you're stewing down tomatoes with celery, onion, leek, carrot, etc...for a tomato soup, or even asparagus, onion, garlic, celery, leek, etc...for a cream of asparagus soup. Include peeled and rough cut russet potatoes with the vegetables when you add your stock. When you go to puree the soup base, the potato serves as a thickener rather than adding a starchy roux.
And for yellow tomato sauce or soup, use some sweet potato, which will amplify the color, as well as thicken.