Also, I would guess that the bagel becomes much thicker as the air pockets expand.
(Anthony ....Did you ever take my advice and get merried??)
Herb Gottlieb from New York City
(Where nationals from all over the world
cab live in peace and harmony)
-- "Anthony Lapinski" <anthony_lapinski@pds.org> wrote:
In discussing heat, I did the ball/ring demo and many students were
surprised to see that the hole EXPANDS when the ring is heated. It's like
expanding a photograph of a bagel -- both the inner and outer diameters
expand. So a student today asked why actual bagels behave differently.
When the yeast is settling, the bagel hole gets SMALLER. As a class we
reasoned that the gas in the yeast releases pressure which expands the
bagel. But why is this behavior different from heating a metal ring? This
question has never come up before, so I thought I'd ask the experts
(since I don't eat bagels much!).