There is a bubble-like air cell inside the egg. Placing the egg
small-end-down stabilizes the air cell, which is on the large end of
the egg, allowing it to "ride" on top of the yolk so that the yolk
stays totally submerged in the albumen ("white") of the egg. The egg
will stay fresher in this position, and the yolk sac is less likely to
rupture. If the egg is placed with the large end down, the air cell
(since it is lighter in weight) will be pressing upwards against the
yolk and albumen, which can deform the yolk and cause portions of yolk
to extend into the air cell rather than staying within the protective
albumen.
I learned this at a local State Fair when I had an interesting
discussion with a young lady who had a 4-H exhibit of chicken eggs in
an incubator. She told me that storing eggs in this way is not only
good for unfertilized eggs in the refrigerator; those who raise
chickens place the fertilized eggs in the same position, since it's
good for the embryo.
Here are some online references on this subject:
"For instance, a freshly laid egg that sits at a temperature of 75
degrees F for one day loses almost 50% of its nutritional value even
though it can still appear "fresh" when broken open. One way of
maintaining and slowing nutrition loss in eggs is to collect them
every two hours and immediately cool them down to 40 degrees F with a
humidity range between 30-50%. The best cooling is in older
refrigerators that are not frost-free. Frost-free refrigeration blows
forced air over the eggs and increases moisture loss. They should be
stored with the small end down so that the yolk is completely
submerged in the egg white, which contains antibacterial properties."
Mary Jane's Farm: The Art of Eggs
http://www.maryjanesfarm.com/SimplyMJ/articles/column14.asp
"Eggs should be collected at the very least twice per day. Put the
small end down in the plastic flats (air cell must be up)."
Organic Valley
http://www.organicvalley.com/member/requirements_eggs.html
"Store eggs small end down in an egg carton to keep the air cell
stable."
Virginia Cooperative Extension
http://www.ext.vt.edu/pubs/poultry/factsheets/9.html
Apparently this method of storage applies to fertilized ostrich eggs
and duck eggs, as well:
"On ostrich farms, storage temperatures may vary from 17 °C to 30 °C,
depending on storage facilities. Apart from storage time and
temperature, the position of eggs during storage may affect
hatchability. Traditionally, eggs are stored in the small-end-down
position before incubation."
South African Society for Animal Science
http://www.sasas.co.za/33(1)pdf/sahan.pdf
"If eggs are stored for a while before they are set, they should be
stored at a temperature and humidity level that will minimize
deterioration of the egg. For a small number of eggs, storage in a
cellar may suffice. Store eggs at about 55°F (13°C) and 75% relative
humidity whenever possible. Store eggs small end down."
Duck Health
http://www.duckhealth.com/hatcduck.html
Google search strategy:
Google Web Search: "eggs" + "small end down"
://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=%22eggs%22+%22small+end+down%22
I hope this information is useful. If anything is unclear, or if a
link does not function, please request clarification; I'll be glad to
offer further assistance before you rate my answer.
Best regards,
pinkfreud |
