119 replies to this topic

[eGCI Team]

Please post questions related to this course here. The eGCI Team requests that you please post relevant questions only. This will ensure the integrity of the learning process.

[enthusiast]

quantity of water

i read somewhere that the more water the better - since this would absorb more flavour. you then concentrate the flavour by reduction. is this right or just a myth? for someone with less than adequate ventilation too much stock reduction is a bore...

[Fat Guy]

I'm sure there's a formula to derive the exact best amount of water for maximum extraction, but I find that covering with water and then adding a little more is good enough for me. As long as you keep the ingredients submerged (you may have to top off the stockpot with more water a couple of times), you're doing fine -- and if you fall asleep and the top layer of ingredients becomes exposed to the air, it's no big deal: some of your ingredients will wind up flavoring the air instead of the stock, but your stock will still be delicous. I agree that too much reduction is tiresome, especially in summertime when it generates so much unwanted heat. If you follow, roughly, the ratios I've outlined, you'll have a very rich stock before you perform any reduction at all. That convenience is, to me, worth whatever small loss of extraction might occur from not using a higher ratio of water to solids.

In some high-end restaurants, they actually make what are called double- and triple-stocks. What this means is that they fill the stockpot with water and ingredients, simmer for a few hours, discard all the ingredients, and then add a whole new set of ingredients to the stock. This creates some damn good stock. Why not just take the first stock and reduce it by half instead of doubling up on ingredients? The double-stock people will tell you that it's not the same -- that reduction doesn't give you as good results as making a true double-stock. But I think for most of us as home cooks it's not a distinction worth pursuing.

[gsquared]

I have a source for good (salt-free) chicken stock and have, in view of my limited need for chicken stock, decided to home in on the brown stock. My daughter has a small (8 quart) pot, and I have a large one (16 quarts), so I am making two batches at the same time. I got two types of meat - one batch with more meat than the other, and have divided the two between the two pots, thinking that it will be interesting to compare the results of a stock made with a larger proportion of meat to the other, more bone-rich one.
More later - I have to skim.....

[Malawry]

Does the type of water used make a noticeable difference? This just occurred to me. I use only filtered water for making coffee, for thinning out sauces, for reconstituting concentrates. (I have a filter, I don't buy water for these applications.) But I use tap water for stocks. Has anybody tried it both ways?

[Fat Guy]

Most restaurants, even the best ones in the world, are using whatever comes out of the tap. But I do know of a few places that have installed filtration systems where the local water supply is particularly aromatic. Once I filled a stockpot entirely from our two Brita pitchers (it took forever!) and didn't notice any difference in the end product, but I bet it might be more noticeable in a quickly-cooked fish stock or something like that. Certainly, when brewing tea or coffee, there's a noticeable difference. But using Evian for stockmaking isn't something I'd even think about unless I was having Alain Ducasse over for dinner -- and if Ducasse came over for dinner I think I'd just give up and order out for pizza.

[Fat Guy]

it will be interesting to compare the results of a stock made with a larger proportion of meat to the other

Excellent idea -- we're looking forward to your analysis.

[Jinmyo]

Rochelle, I have filters installed on the taps. Ottawa water isn't horrible but the filtered tastes so much brighter. So I always uuse filtered water for soups and stocks.

If it's easy to do it, it's worth doing it.

A double or triple reduction of chlorine...

[Dave the Cook]

The causes of the most objectionable odors in tap water (mostly sulfur compounds and the like) are volatile and decompose as the water heats. Almost all of it will completely break down during the long simmer. The rest of the stuff is tasteless or is rendered tasteless; is trapped by the other stuff in the water as precipitates or compounds; or is overpowered by the flavor of the stock.

Having said that, I wouldn't be surprised if an astute palate might not pick up some residual note that others would not -- chlorine, for instance, or iron. Filtration is always an option, or bottled water, which is not terribly expensive if you avoid the portion-size bottles and buy a five-gallon jug instead.

Incidentally, finished stock is mildly alkaline.

[enthusiast]

in a spirit of inquiry rather than rudeness...

Incidentally, finished stock is mildly alkaline.

so what?

[Fat Guy]

I'm pretty sure alkaline stock makes better batteries than regular stock.

[Dave the Cook]

in a spirit of inquiry rather than rudeness...

Incidentally, finished stock is mildly alkaline.

so what?

Hence my use of "incidentally." I think it's interesting. But then, I'm a geek.

On the other hand, if you use stock to simmer vegetables, especially dried beans, knowing this might save you some head-scratching on down the line.

I'm still working on the Introduction to Kitchen Science lesson. If there's interest, maybe we'll cover this.

Another note on volatile compounds in tap water: if you fill a bowl with tap water and sniff it, you'll probably note the presence of chlorine, among other things (iron and sulfur are the most common). Leave the bowl open (or cover it with cheesecloth), and let it sit on the counter overnight. In the morning, you'll find that most of the odor is gone (along with most of the dissolved oxygen, which is responsible for most of the "fresh" taste of water). Simmering will only accelerate this effect.

FG: what about lithium stocks? I hear they're quite soothing.

[Fat Guy]

I currently favor NiMH stocks, but I digress . . .

[Fat Guy]

Folks, I'm signing off for now, and will be back online tonight to answer questions, as will Carolyn. Don't forget to post your photos. Thanks!

[Rachel Perlow]

it will be interesting to compare the results of a stock made with a larger proportion of meat to the other

Excellent idea -- we're looking forward to your analysis.

You can actually have three products to compare - the meaty, the boney, and a mixture of the two. My prediction? That the mixture will have the best combination of gelatinous mouthfeel and meaty taste.

[gsquared]

You can actually have three products to compare - the meaty, the boney, and a mixture of the two. My prediction? That the mixture will have the best combination of gelatinous mouthfeel and meaty taste.

Meaty and boney both contentedly simmering away - meaty looking paler, but perhaps only shy due to being in a smaller pot.

[alacarte]

Can you recommend some alternative aromatic vegetables to use? Would fennel or mushrooms work?

[CityCook]

I'm still working on the Introduction to Kitchen Science lesson. If there's interest, maybe we'll cover this.

absolutely there's interest, if only my interest. I think it's indispensable.

[gsquared]

Just for interest's sake, I took 3 small samples of my brown stock (the boney one) at different times, and strained each sample. Here are the results at, from left to right, 1 hour, 3 hours and 12 hours.

This is not very scientific (I wanted to it every 3 hours but got distracted!) , but it does look as though the bones still added a lot of colour after 3 hours.

[Rachel Perlow]

Did you chill your samples to examine the strength of the gelatin at the various time points?

[Bux]

What factor might evaporation have played in regard to the relative strengths of the broths.

[gsquared]

Did you chill your samples to examine the strength of the gelatine at the various time points?

I chilled the first two samples immediately after taking them. Did not specifically test for gelatine, though, but the both samples were watery and not gelatinous at all, as I observed when pouring them back into the stock. The last sample was still warm....Damn! I'll make a poor scientist.

What factor might evaporation have played in regard to the relative strengths of the broths

There must have been some evaporation, but I doubt that it played much of a role - in any event, evaporation would have made the first two samples darker, no?

[Fat Guy]

Great photos, G2! I'm kicking myself for not documenting the same sort of thing when I was preparing the lesson. Then again, I slept through most of it.

On the Unit 1 Q&A thread, there was a great post about the science of all this, and one of the points made -- which reconciles entirely with my experience -- is that there's a Maillard reaction that occurs continuously throughout stockmaking. A white stock will eventually become a brown stock, in other words, even if you don't oven-roast any bones or add any tomato product. Its flavor may develop a bit differently, but color will occur. Evaporation won't explain it, because you'll get the brown color even if you keep topping off the water supply with fresh water. There's also no question that there will be a ton more gelatin in a 12-hour stock than a 3-hour one. I don't know how we'd measure the amounts without special instruments, though.

G2, did you taste those samples? Notice anything?

[Jason Perlow]

By the way, French Laundry Cookbook author Michael Ruhlman posted a very interesting answer to a question about "self clarifying" stocks:

http://forums.egulle...&f=109&t=25342

[gsquared]

G2, did you taste those samples? Notice anything?

Yep - in the first two the mirepoix was dominant. In the first one, I picked up mostly celery, the second one a more general "veggie" taste with the onions being distinct. The last sample tasted the way I expected the completed stock to taste - the mirepoix was still there, but as part of a far more complex flavour.

[Fat Guy]

Can you recommend some alternative aromatic vegetables to use? Would fennel or mushrooms work?

When I did the shopping for the lesson, I actually bought a fennel bulb. It's one of my favorite aromatic vegetables for stockmaking, and in particular I consider it almost essential to a good shellfish stock. Ultimately, I decided against using it because it didn't fit with the way I outlined the class, so you'll see it used as a leftover in one of the recipes at the end of Unit 3.

Mushrooms are a bit trickier. I wouldn't put them in with the mirepoix in a long-simmered stock. I'd only add them at the late stages if you specifically wanted a mushroomy flavor. You can also use the (well strained) liquid from soaking dried mushrooms -- an excellent use of this byproduct.

Leeks are a milder alternative to onions and are especially useful in fish stocks when you want mildness. Parsnips can pinch hit for carrots and will help keep a stock whiter.

In Asian-style stocks, garlic, ginger, star anise, and other aromatics from that culinary style can be added. And of course you can add just about any herb or whole unground spice, especially if you're trying to enhance a flavor you ultimately plan to use in a finished dish or sauce.

[Fat Guy]

G2, did you taste those samples? Notice anything?

Yep - in the first two the mirepoix was dominant. In the first one, I picked up mostly celery, the second one a more general "veggie" taste with the onions being distinct. The last sample tasted the way I expected the completed stock to taste - the mirepoix was still there, but as part of a far more complex flavour.

The moral of the story being that if you want a vegetable stock with clear vegetable flavors, you should do a short simmer, and if you want a classic full-bodied meaty-tasting stock with serious thickening power you should do a long simmer!

[Dave the Cook]

There's also no question that there will be a ton more gelatin in a 12-hour stock than a 3-hour one. I don't know how we'd measure the amounts without special instruments, though.

To approximate a quantitative measurement, dissolve specific weights of gelatin in specific volumes of water, measure their setup times and create a spreadsheet.

Then deposit similar amounts of each sample into identical containers, time how long it takes each to set up (though some will not set up at all), and compare to your spreadsheet.

Edit: a really interesting project would be to graph gelatin development over time.

[jackal10]

On the Unit 1 Q&A thread, there was a great post about the science of all this, and one of the points made -- which reconciles entirely with my experience -- is that there's a Maillard reaction that occurs continuously throughout stockmaking.

Thanks. I think that was my post, and was a little discouraged as no one took it up.
I'll try and get something done as input for the Kitchen Science unit. It should certainly cover Maillard reactions, at least in outline - I don't think anyone really understands the fine details.

Edited by jackal10, 04 August 2003 - 01:18 PM.

[Fat Guy]

I think that was my post, and was a little discouraged as no one took it up.

As I'm particularly weak on the scientific details of all this stuff, additional science-oriented information is always appreciated. I don't think you'll get much direct reaction to it -- the idea of these threads is to answer questions rather than engage in too much crosstalk -- but people are surely glad to read those enhancements to the lesson material, as am I. Thanks.