I missed the original query so I'm responding to it via the
response posted by Puester who posted good advice.
In article >,
Puester > wrote:
= <RJ> wrote:
= > We moved from an area near sea-level
= > to a town, elev. 4500 feet.
= >
= > Suddenly, these cautions about high-elevation cooking are real.
= >
= > The general cure seems to be ..."add some flour".
= >
= > But why does it work ?
= > Why do my initial batches seem underbaked ?
It could be related to the lower boiling point of water at higher
altitudes. While your oven may be set to a temperature in excess
of 300 degrees Fahrenheit, the internal temperature of any thing
that contains water cannot exceed the boiling point of water.
While that's 212 degrees F at sea level, it is quite a bit lower at
higher altitudes.
Whether there's enough difference between sea level and 4500 feet
ASL, I don't know offhand but as the OP suggested, contacting the
extension service at any of the higher altitude states would be a
good approach.
Here's the URL of the one suggested by the OP:
http://cerc.colostate.edu/titles/P41.html
According to that site, the boiling point of water at 5000 feet is
203 degrees vs. 212 degrees at sea level. At 4500 feet, it would,
of course, be slightly higher than 203 but not much. Using that
chart, one can calculate the BP change per foot of altitude or,
perhaps, more convenient, per hundred feet.
For each foot of altitude increase, the BP of water decreases
0.0018 degrees F, 0.18 degrees per hundred feet, or 1.8 degrees
per thousand feet.
According to that site, the compensation for cakes made with
shortening is to decrease the amount of leavening (i.e. baking
powder):
Cakes Made with Shortening
Most cake recipes perfected for sea level need no modifications
up to 3,000 feet. Above that, decreased atmospheric pressure
may result in excessive rising, which stretches the cell
structure of the cake, making the texture coarse, or breaks the
cells, causing the cake to fall. This usually is corrected by
decreasing the amount of leavening agent. Also, increasing the
baking temperature 15 to 25 degrees "sets" the batter before
the cells formed by the leavening gas expand too much.
Excessive evaporation of water at high altitude leads to high
concentration of sugar, which weakens the cell structure.
Therefore, decrease sugar in the recipe and increase liquid.
Only repeated experiments with each recipe can give the most
successful proportions to use. Table 3 is a helpful starting
point. Try the smaller adjustment first, this may be all that
is needed.
In making rich cakes at high altitudes, you might have to
reduce shortening by 1 or 2 tablespoons. Fat, like sugar,
weakens the cell structure. Also, increasing the amount of egg
strengthens the cell structure and may prevent the too-rich
cake from falling.
And Farther down:
Cake Mixes
Adjustments usually take the form of strengthening the cell
walls of the cake by adding all-purpose flour and liquid.
Suggestions for high-altitude adjustments are provided on most
cake mix boxes. Follow these suggestions.
So, apparently the answer to your question as to *why* one does
that, is that adding flour strengthens the cell walls (i.e. the
walls of the bubbles that make the cake rise) while decreasing the
leavening decreases the force on those walls. In either case, the
idea is to keep them from becoming to large (a coarse texture) or
bursting (a fallen cake).
There's a great deal more information at that site for all sorts of
cooking. Take a look.
Incidentally, while I rarely use box mixes (where I have seen the
high-altitude adjustments), in general I seldom bother with
high-altitude compensation. I presently live at about 6500 feet
ASL and previously lived at about 7500 feet. Naturally, YMMV...
Would some things that I bake be improved by making the adjustments?
Quite possibly but the results are satisfactory to me.
I'm sure it depends a lot on what you happen to be cooking.
Finally, from the web site cited above:
Practical Baking Notes:
1. Flour, use any brand of enriched all-purpose flour (or cake
flour, if called for by the recipe).
2. Do not assume that your sea level recipe will fail. Try it
first. It may need little or not [sic] modification.
I specially like #2.
= > I've got a lot of recipes in my notebook.
= > Is there some general cure I can apply to all of them ?
= >
= > <rj>
=
=
= Write to the County Extension Service at Colorado State University
= in Ft. Collins, Colorado and ask for their printed information about
= cooking/baking at altitude.
=
= gloria p
--
Charlie Sorsby
Edgewood, NM 87015
USA