Ideas for a cold, stock-based sauce or dressing

[jmcgrath]

Could someone enlighten me on why freezing an egg yolk enhances its emulsifying power. This is a tip I have never run across before.

Jim

[Dave the Cook]

Could someone enlighten me on why freezing an egg yolk enhances its emulsifying power.  This is a tip I have never run across before.

Jim

Again quoting from Harold McGee's The Curious Cook:

Ever since (the 1920s), most commercial mayonnaise has been made with frozen yolks, about one-third yolk per cup of sauce. The chemistry of yolk thickening is still something of a mystery. The current theory is that freezing deprives the yolk's emulsifier-protein particles of their protective layer of water by solidifying the water into ice crystals, and this causes the particles to bond to each other.

He doesn't go into this further.

Most of the emulsifying power in an egg yolk comes not from the "protein-emulsifiers" McGee mentions, but from the phospholipid lecithin. I deduce that freezing is suspected of adding to the already substantial emulsifying capacity of the yolk by loosening this previously untapped source.

That's my guess, anyway.

[Fat Guy]

Freezing also has a food-safety benefit, does it not?

[fifi]

Freezing only helps health wise with storage time. Freezing doesn't kill the little salmonella buggers.

[Dave the Cook]

Freezing only helps health wise with storage time. Freezing doesn't kill the little salmonella buggers.

Correct. In fact, under certain conditions, some strains of salmonella actually thrive at sub-freezing temperatures.

I haven't tested them, but I'd bet you could use pasteurized eggs in combination with the freezing technique, and get the best of both worlds.

[jmcgrath]

Could someone enlighten me on why freezing an egg yolk enhances its emulsifying power.  This is a tip I have never run across before.

Jim

Again quoting from Harold McGee's The Curious Cook:

Ever since (the 1920s), most commercial mayonnaise has been made with frozen yolks, about one-third yolk per cup of sauce. The chemistry of yolk thickening is still something of a mystery. The current theory is that freezing deprives the yolk's emulsifier-protein particles of their protective layer of water by solidifying the water into ice crystals, and this causes the particles to bond to each other.

He doesn't go into this further.

Most of the emulsifying power in an egg yolk comes not from the "protein-emulsifiers" McGee mentions, but from the phospholipid lecithin. I deduce that freezing is suspected of adding to the already substantial emulsifying capacity of the yolk by loosening this previously untapped source.

That's my guess, anyway.

I think it's time for an experiment. The use of frozen egg yolks in commercial mayonaise may just be a matter of convenience. I'm an engineer and fairly proficeint home cook, not a professional cook in any sense. The experiment must have repeatable results to be valid.

1 extra large egg yolk frozen for 2 hours and then defrosted to refrigerator temperature.

1 extra large egg yolk at refrigerator temperature.

The rest of the ingredients are identical:

1/2 Tbsp fresh squeezed lemon juice.

1/2 tsp Maille Dijon mustard

Inexpensive EVOO (e.g. Bertoli)

Add yolk, lemon juice and mustard to blender and blend for 10 seconds at high speed. Start dribbling in oil 1 Tbsb at a time until emulsion no longer incorporates oil.

Does anyone want to change proportions or process before running the experiment?

I'll go first.

Jim

[Dave the Cook]

The use of frozen egg yolks in commercial mayonnaise is a matter of convenience. It's much easier to control frozen inventory than something that has a shelf life of a couple of weeks. But it's also economics. If you're making millions of gallons of mayo, cutting the cost of your eggs by two thirds can make a big difference in the bottom line. If you can make a mayo with consumer-acceptable consistency using only a third of a yolk, why waste it?

But a home cook, who probably doesn't care about the expense of an extra egg, can exploit this. You can reduce your consumption of cholesterol (let's not get sidetracked into that discussion, please!), or (the big thing for me) you can make a thicker mayonnaise without overloading it with egg flavor. This gives you a neutral medium for say, veal stock, or soya, or almost anything. That's a nice trick to have in your bag.

In any case, before you proceed, you might want to read the entire mayonnaise chapter in McGee's book. I won't get into a lot of paraphrasing here, but in short, your blender will probably overflow before you exhaust the emusifying capacity of either yolk starter. You'll need to divide the mixture along the way so that you can continue without consuming unreasonable amounts of oil. In other words, make two cups of sauce, then divide it back down to maybe a half-cup, and continue adding oil. And maybe a blender might not be the best method for making mayonnaise in a quantity greater than a cup or two -- once you've got a stable emulsion, a stand mixer at medium-low will probably do a better job. For each cup of oil, you need to add a tablespoon or two of water-based liquid -- remember that the emulsion is not between egg and oil, it's between water and oil.

Also, McGee points out (admittedly without understanding why) that unrefined oils, e.g. EVOO, are not as mayo-stable as others. This might be one reason why we don't see "gourmet" mayo made with EVOO at the grocery store. If you're simply looking to find out what a practical limit for emulsification, a neutral, refined oil (or a blend of say, 75% safflower/25% EVOO) will suit your purposes better. And you'll need a lot of of it.

So I'm interested in your experiment, but I'm not sure what you're trying to prove. Could you clarify?

[jmcgrath]

So I'm interested in your experiment, but I'm not sure what you're trying to prove. Could you clarify?

I was trying to determine if freezing the egg yolk was worth the bother for a home cook. You have convinced me that it is if the intention is to reduce cholesterol or a create a more neutral mayonaise, but probably not otherwise.

Thank you for the wealth of information and I think I will forgo the experiment. There is no need to tread where experts have gone before.

Jim

[Marlene]

Added to the archive:

Using Frozen Egg Yolks to make mayonnaise

Beef Mayo

Sauce for Brisket

Courtesy of Dave the Cook

[Dave the Cook]

So I'm interested in your experiment, but I'm not sure what you're trying to prove. Could you clarify?

I was trying to determine if freezing the egg yolk was worth the bother for a home cook. You have convinced me that it is if the intention is to reduce cholesterol or a create a more neutral mayonaise, but probably not otherwise.

Thank you for the wealth of information and I think I will forgo the experiment. There is no need to tread where experts have gone before.

Jim

You went through pretty much the same thought process I did.

It also turns out to be a good techinique for getting a really thick mayo that you want to dilute, as in FG's recipe.

Thanks, Marlene.

[Carlovski]

I just can't get the concept of beef mayonnaise out of my head now, it sounds wrong, but o so right!

Though now I keep thinking of variants. Beef custard anyone?