Date: April 2009
Why does spaghetti curve when cooked in hot water?
I am not quite sure what you are asking in your question -- do you mean why is
cooked pasta flexible, but dried pasta is not? Spaghetti is made mostly of a
long type of molecule called 'starch'. When wet, the starch molecules inside
the pasta can slip and slide past each other, making for flexible, bendy pasta.
The water is a little like a lubricant for the starch. When dried, the water is
gone, so the starch molecules 'lock' into place, and become stiff. When cooked,
water can get back in to the noodle, and the noodle becomes flexible again.
Hope this helps,
Starch molecules can be considered as a long chain molecules that in uncooked
spaghetti has been frozen into a shapes that retain a linear uncooked spaghetti form
and is made that way from the production process. In this process, water is removed
from the uncooked spaghetti while the pasta is in a linear shape and so the molecules
conform to structures that retain the linear shape. The linear, stiff pasta is only
this way because there is no water. (In contrast, for example, freshly made pasta is
actually soft and pliable.)
When the pasta is cooked, the starch molecules are rehydrated - water goes back into
the starch which then are able to go into structures that are more pliable. The starch
molecules go into structures that they were in before they were straightened and
Greg (Roberto Gregorius)
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Update: June 2012