A good egg

Royal Society of Chemistry ^ | 27 May 2009 | Anna Roffey

[neverdem]

UK and Dutch scientists have mimicked an ancient Chinese culinary technique of preserving eggs to study how proteins cause disease.

Erika Eiser from the University of Cambridge and colleagues looked at how proteins in egg whites altered during this preservation process. The Chinese method involves wrapping raw eggs in an alkaline paste of lime, clay, salt, ash and tea and storing these so-called century eggs for several months. Eiser modified the method by incubating a boiled egg in a strong alkaline sodium hydroxide-salt solution for up to 26 days.

Hard boiled egg whites become a transparent gel in an alkaline solution

After peeling back the shell, Eiser found that the egg white had transformed into a gel. This transformation is caused by changes in the way protein strands, called ovalbumin, in the white are held together. Boiling an egg causes bonds between the protein strands to break and the proteins to partially unfold. The proteins then come together, or aggregate, in a different way to form the opaque and brittle white. The transformation was thought to be irreversible, but the alkali causes the proteins in the white to aggregate into fine strands to form a transparent and elastic gel. Eiser found that the gel was more stable than the white, and could be heated without changing its structure.

Paul Bartlett, an expert in colloids and protein aggregation at the University of Bristol, UK, comments that Eiser's findings 'will be important for understanding protein gels and will inspire more work in colloidal materials.'

'Similar chemical transformations could be used to change the properties of protein aggregates not only in food but also in other biomaterials,' says Eiser, who plans to test the method on different proteins. 'If we understand the mechanism that drives aggregation then we could slow it down or reverse the aggregation into something else.' This could be important in preventing diseases caused by unnatural protein aggregation such as Alzheimer's.

[neverdem]

Molecular cooking: physical transformations in Chinese century eggs

[WKUHilltopper]

“This could be important in preventing diseases caused by unnatural protein aggregation such as Alzheimer’s.”

Cripes! You’d have to have Alzheimer’s to eat one of those eggs.

[clockwise]

Ingredients
2 cups black tea very strong
1/3 cup salt
2 cups ashes from pine wood, ashes charcoal and ashes from fireplace
1 cup lime
12 Fresh duck eggs
Directions

These are often called thousand-year eggs, even though the preserving process lasts only 100 days.

Combine tea, salt, ashes and lime.

Using about 1/2 cup per egg, thickly coat each egg completely with this clay-like mixture.

Line a large crock with garden soil and carefully lay coated eggs on top.

Cover with more soil and place crock in a cool dark place.

Allow to cure for 100 days.

To remove coating, scrape eggs and rinse under running water to clean thoroughly.

Crack lightly and remove shells.

The white of the egg will appear a grayish, translucent color and have a gelatinous texture.

The yolk, when sliced, will be a grayish-green color.

To serve, cut into wedges and serve with sweet pickled scallions or any sweet pickled vegetable.

Sauce can consist of 2 tablespoons each vinegar, soy sauce and rice wine and 1 tablespoon minced ginger root.

http://recipes.recipeland.com/recipe/v/Thousand-Year-Old_Eggs_21726

[Peter W. Kessler]

>>>The white of the egg will appear a grayish, translucent color and have a gelatinous texture.

The yolk, when sliced, will be a grayish-green color.<<<

Wow. That sounds yummy.

Blech!

[Straight Vermonter]

This could be important in preventing diseases caused by unnatural protein aggregation such as Alzheimer's.

Help your fellow freepers fight Alzheimer's. Join the team.

[happygrl]

This is your brain.

This is your brain when preserved by traditional Chinese culinary techniques.