Clarifying Homemade Chicken Stock With Egg Whites - Fail
I made, probably one of my more successful batches of chicken stock yesterday. This time around I actually saved up a bunch of fresh chicken bones and skin, much more than I would normally use, and I also added an "acid" per some suggestions, in the form of some fresh chopped tomato. I didn't use any whole pieces of chicken either, just the bones and skin.
The result was a very dense broth (I made it in my pressure cooker) with a great mouth feel. I let it cool overnight so I could skim the excess fat off. But I also figured, if I went this far, why not really perfect it and attempt to clarify it into a "consomme".
I don't have any cheese cloth on hand, so I've only been straining the broth through a fine metal strainer. The broth itself actually looked pretty clear to begin with, but of course I wanted to see how far I could take it.
The method I had always heard of was to use egg whites, cooked in the broth to catch any debris, then strain it again to get a crystal clear broth. Some methods suggested adding even more ground meat and vegetables for this process, but I was worried these extra ingredients would muck up the broth even more, so I left them out.
I scrambled up some egg whites until a bit frothy, brought the broth to a simmer and added them. They eventually formed the "cloud" as described and I let it all cook a while longer. Then I strained it through the metal strainer. Total fail.
The resulting broth was even cloudier, had an "egg white" taste to it, and a lot of the egg white debris made it through the strainer as well.
Have any of you ever done this egg white method successfully? I'm wishing I would have just left the perfectly good stock alone after de-fatting it, lol.
you need to bring the broth to a high simmer or even a low boil before adding the raft -- then you turn the heat off, let cool, and restrain.
That's the only difference I see -- I don't think your broth was quite hot enough.
I don't clarify a lot, because I'm usually adding other stuff to the stock to make the clarity a non-issue, but the few times I've done it, the rapid-simmer worked fine.
Not sure if you could do it again...or maybe strain through paper towels or an old dish towel (clean)?
Never tried it myself but the pictured method I saw in a cookbook years ago used freshly crushed raw eggshells saying you only need the little bit of white left clinging to the shell. Stir that mess in and let it go until it literally forms a hard crust on top. Carefully remove crust and strain. Made sense to me anyway.
The fact you used a pressure cooker meant you heated the protein strands over 212 F. When this happens the protein strands not only turn into basically rubber bands but they also 'blow apart'. This means the liquid has millions of chards of protein in it. These bits of protein are too small to use any 'raft' to remove them to the point were you'd end up with a consomme.
If you want to make a very clear stock the only way is to avoid at all costs bringing the liquid above 212 F.
I make sure my stocks go no higher than 200 F. 'Low and slow'. For chicken stock I always add a couple of fresh raw pork bones and a hand full of leaks. Never any salt or herbs at this point. Anyway. Then skim skim skim at first to remove anything that floats to the top. This doesn't take too long when the stock gets up to temp.
A little tip: Move your stock pot slightly off the burner. This will cause one side of the stock pot to be a higher temp than the other side. This causes a very gentle vertical convection which gently moves particles over to one side where they are easier to skim off.
After the stock has simmered uncovered for a couple of hours I allow it to cool completely overnight. Any fat can then be very gently removed from the surface. I carefully ladle off the now clear stock. I do not pour it off as this will cause whatever has settled to the bottom to be disturbed thereby wasting any effort I put into achieving a clear stock.
This clear stock I freeze in Zip locks bags for future use. Should I want to make a consomme, which I don't foresee happening, the stock is now ready to be 'rafted'. I've made consomme a few times years ago just to do it.
Bottom line: don't use a pressure cooker if you want a clear stock.
Next time use ground chicken and egg whites. Its the tomato and mirepoix that can be left out, IMO.
Mix the ground chicken and slightly whipped egg whites together and add to cold chicken stock in a stockpot.
Turn on the heat and bring to a gentle boil, stirring occasionally. You'll see the raft come to the top and come together.
Once the raft has formed, turn the heat down to a simmer and let it go for an hour. You should be able to see how clear the stock has become during the process.
Once clarified, carefully remove the raft and strain the consommé through cheesecloth.
Puffin has a good point, though. If you make stock by hard boiling it, you emulsify the fat, making it very hard, if not impossible, to remove.
re: C. Hamster
Wrong. The whole point of pressure is to raise the boiling point of water and thereby cook at a higher temp than 100C, the max allowed by boiling water. You can probably boil water in a pressure cooker, but only if you weld up the popoff valve, which is there for that exact purpose.
Pressure is created by adding energy, ie heat, to the gas molecules, including water vapor, which increases their activity. In an unconfined environment, the gas expands; in a closed vessel the pressure rises. PV = NrT.
You are, of course, aware that water boils at a lower temp at altitude due to the lower ambient air pressure, right?
Sigh. Let's take it from the top, using real numbers, ok?
For every pound/square inch (PSI) above normal atmospheric pressure, the boiling point of pure water goes up by about 3 degrees. No mythology here, just chemistry.
The high pressure setting on a Kuhn-Rikon pressure cooker, which is a highly regarded brand, is at 11.6 PSI. The maximum before the blowout gasket blows is 17.4:PSI. At 11.6 PSI, the associated water temperature is 243 degrees F. Since at a pressure of 12 PSI, water boils at 248 degrees F, it doesn't boil in the pressure cooker. The device is engineered to keep the water just below its boiling point at a given pressure, which is the point of maximum heat transfer. And even at the blowout pressure of 17.5 psi, the water is still about 10 degrees below its boiling point.
Here -- look it up.
Science can be so annoying sometimes.
we went through this before. It allows the mixture to attain a higher temperature than 212 for a longer period of time.
But you still have to bring it to a boil to build up enough steam to close the seal on the pressure cooker.
You then turn down the heat so you maintain the boil....
re: C. Hamster
One detail that C. Hamster recommends that I think is essential is starting with COLD broth.
When the egg whites are slowly heated along with the broth, there's a lot more opportunity for clarifying.
While this isn't necessary for most applications of stock, it's important to remember the value of a well-made consommé.
And ground meat and aromatics in the raft absolutely enhance the flavor of the liquid.
Some of the recommendations here are out to lunch. I hoped they are backed up by real world results.
I learned the correct way from Elizabeth David's books, and it is derived from Escoffier.
Make your stock as usual (PC is fine) and when strained and chilled, remove every scrap of fat. All of it has to be removed.
Slowly bring the stock to a simmer. Whisk several egg whites to a frothy stage and slowly add them to the stock. Simmer and stir very gently.
They will form curds and sink, taking the cloudy parts with them, in about 20 minutes.
Strain through cheesecloth, and you'll have a crystal clear broth for consomme or jellied preparations.,
A cook in any pro. kitchen who is tasked with making stock who allows the stock to come to a boil doesn't work there for long.
Where I worked there were always at least a couple of 10 stock pots slow simmering away on the back of flat tops.
Each with valves a few inches off the bottom of the pots. The restaurant's line chef/cooks had a couple of smaller pots always on the go decanted from the main pots.