Wednesday, August 4, 2010

:: notes about eggs ::

On Sunday, after the New Amsterdam Next GINeration Cocktail Challenge, Andrea and I caught our last seminar at Tales of the Cocktail 2010, "The Eggpire Strikes Back," hosted by Timo Janse, Andrew Nicholls, and Henrik Hammer. The presentation covered everything from the historical and philosophical aspects of eggs to the practical ones suited to the bar. Eggs have been used in beverages and frozen desserts since 3000 B.C. and only recently have come under attack. Perhaps some of the fear of eggs has always existed, but these issues have become more to apparent in recent history. The presenters even spoke of the chemical egg white substitute called Mr. Frothy -- a few drops gave a foam, but when tasted neat, it had a horrible bitter flavor and an unattractive aroma. Before jumping into the more practical aspects, I need to pass on their recommendation to read On Food & Cooking by Harold McGee. My copy is coming via Amazon, so for now, I take their recommendation without question.

Do's and Don't Concerning Creamy Heads on Drinks:

• Fresh eggs work best.
• Refrigerate your eggs. Eggs age four times faster without refrigeration.
• Use only as needed and do not batch in advance.
• The more water, the more foam.
• Too much water, the less foam.
• The presence of acid increases the foam amount.
• It needs to be absolutely free of detergents.
• Pre-shaking with just the egg white helps to set up the foaming capabilities.
• Adding a balled up Hawthorne strainer coil can help to foam up the egg white in this pre-shake. Remove the coil before adding rest of ingredients and ice.

There was a bit about egg physiology and biochemistry that was quite interesting to me (I am a classically trained biologist), but to spare the details and get to the nitty-gritty of how this will effect your drinks, here are the pointers:

• Egg white serves to bind ingredients together, provides texture, donates an attractive layer of foam.
• Protein is bound up in knots in the egg white. Movement unwinds these knots and causes them to branch out. In this branching out process, one peptide chain will grab onto another and cause them to stick together. In this process, air can get trapped.
• It is possible to over do this "movement" step by over-agitating/over-shaking.
• Eggs can absorb flavors in the refrigerator. As an egg ages, it generates sulfur compounds, but the more complained about off-flavors are absorbed, especially those that come across as "wet dog" aromas.
• Use the egg's absorption of odors to your advantage. Store eggs in a sealed container with white or black truffles, lemon oil-soaked cloth, or other aromatics to give them a more pleasant smell instead.
• Store your eggs so that there is less movement. Fridge door (the traditional place refrigerator manufacturers put the egg drawer) are the worst since the constant opening and closing weakens the egg white.
• Egg white is filled with umami (the 5th taste after salty, sour, bitter, and sweet) and acts as a flavor enhancer.
• Different species of fowl provide different flavors. The diet of the bird will affect the flavor of the egg greatly. Yes, ostrich egg will work.
• To re-create historic egg yolk-containing pousse-cafés, like the Knickebein, quail egg is probably the most accurate today to replicate the chicken eggs of yore.

In terms of the health fears, it has been covered elsewhere in depth, but here are the highlights:

• Salmonella, if present, is exclusively on the outer shell.
• Frequency is one egg in every 20- to 40-thousand, or one egg per person every 84 years.
• It takes 3-5 weeks for this bacteria to develop so use fresh eggs.
• There is more risk if eggs are cracked and sit around before being used. This gives the bacteria time to grow in numbers (especially since the bacteria from the outside of the shell would come into contact with the energy-rich inside of the egg at this point). The danger is in the improper handling of food, not in the use of eggs per se.
• Salmonella targets the sick, pregnant, very elderly, and very young which are four groups who should not be drinking egg cocktails in the first place.
• Eggs have a lower incidence of Salmonella than lettuce (unsure if he meant bacteria in general or Salmonella specifically).
• 17.5% alcohol by volume kills Salmonella.

4 comments:

Russos said...

very informative, thanks.

Anonymous said...

Thanks for posting all this--it may help me overcome my irrational fear of raw eggs...

Elvira said...

Very interesting, I now know much more about eggs than before, (I will no longer put my eggs on the refrigerator door, for example,)but I still have one question that is not answered. You say that: "Refrigerate your eggs. Eggs age four times faster without refrigeration." But then, why do we always find eggs far away from the refrigerator at the supermarkets?

frederic said...

The eggs I buy at the supermarket are always in the refrigerator case.

I have definitely seen eggs stored at room temperature. For eating, they would probably be fine as they age (I know that the omelets made during my grad school days using eggs kept in my fridge for months after the expiration date never did me in). But for cocktail use, they will be less optimal. This doesn't even cover nutritional loss due to breakdown or other. The places that store the eggs at room temperature might do so to save on refrigeration cost or expect a high turn over or do not care about quality as much as profits. If the eggs are used soon after laying, I believe that they would be fine not kept chilled.