h a l f b a k e r y
Experiencing technical difficulties since 1999
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
or get an account
Many hours are wasted waiting for water to boil off sauces
and such to produce a thicker tastier product. There are
several ways to speed this up, you can use a shallow, wide
pan to increase surface area. You can aim a fan at the
surface, this blows water vapor away from the surface
the partial pressure and enhancing further
evaporation. You could also move the pot to an
advantageous location, Vostok station or the summit of
Everest come to mind. Here, low-pressure high wind
speeds and very dry air would really speed the process at
the cost of some convenience.
An alternative would be to manufacture a pot lid with a
Peltier thermoelectric cooler built in. The cold side should
face down onto the inner-lid, a dome-shaped condensation
surface. Around the inner perimeter, a shaped rim collects
the condensate and a small gear-type pump moves the
water to a waiting tube for collection. The hot side of the
Peltier should be attached to the outer lid which is
separated from the inner condensation lid by fiberglass
In operation, the lid will be placed on a boiling pot. After a
few seconds, the steam will displace any air in the space
above the liquid. Adding power will cool the inner lid. This
will condense water vapor to be pumped out, this will
dramatically increase the evaporation rate. Your sauce
will thicken up much faster.
[FlyingToaster, Jan 22 2019]
||Excellent idea [+] you might get away with cooler
temperatures too since there's always going to be a
degree of vapour at the top of the pan - creaming
this off would encourage additional evapourage.
||Adding a vacuum and gasket seal would improve
||//encourage additional evapourage.//
||I'm stealing "evapourage". I'm going to build the marketing
around it in fact. When I'm finished, it will be industry canon
that "evapourage" is a mainstay of classical French cooking.
||A vacuum process is going to be much more energy-efficient than a Peltier device.
||However, the pump will need to be carefully selected. Fortunately the pressure gradient required isn't high, but the pump will either need to be water-lubricated, or have a lubrication system that copes with wet steam.
||Alternatively, an oscillating-diaphragm pump with no sliding contacts would work well, as the liquid should be almost pure.
||As a bonus, you get a free supply of distilled water out of the condenser.
||//free supply of distilled water out of the condenser.//
||I doubt the liquid would be pure, there's spattering on the
inside of any lid I've ever used, then there's any volatiles in
the food, ethanol from wine for example. A stern warning in
the manual should state, that under the wrong conditions
(several examples should be shown as what not to do) the
equipment might be used for the production of high
concentration alcohol. Which is to be avoided. Obviously.
||So, what's the difference between this and boiling without a lid ?
||// So, what's the difference between this and boiling
without a lid ?//
||There IS a lid. That's the main difference. The vacuum
reducer is getting there with a vacuum pump alone. This is
getting there with a condenser, which will create some
vacuum in combination with the scavenge pump. This is
more complicated and less efficient, so I'll compensate with
aggressive marketing. On late night TV "Solid-state
evaporage" is a winner.
||If you fling it skywards, then photograph it, do the
resulting pics look like a UFO?
||Good grief, [bs]. Surely you have ample access to a Rotavap
or a Speedvac?
||//Surely you have ample access to a Rotavap//
||I have access to all sorts of things, most don't. Sadly
bringing a sauce to work isn't that convenient and I
haven't successfully lobbied for an in-building serviced
||Actually, there was a nearly new rotavap in a recently
closed lab. I asked and wasn't allowed to have it, so it
sat. Then I saw it smashed and bent in a skip, worse than
book burning if you ask me. Strange is the convoluted
nature of ownership when it comes to scientific
||//bringing a sauce to work isn't that convenient// No, I was
thinking the reverse.
||//I asked and wasn't allowed to have it// The trick is to take
it, and then wait for someone to ask for it back. Most of my
company's equipment has arrived in that manner.
||// The trick is to take it, and then wait for someone to
ask for it back.//
||I've learned a variety of techniques since that incident.
When legitimately acquiring old equipment, they're often
marked with stickers/tape with "Smith lab, do not
remove" and sometimes old asset tags from one of the
many attempts at central control of lab equipment*. Such
stickers should be harvested and kept to demonstrate the
legitimate providence of any newly acquired resources.
Also, brake clean does a very good job of eliminating all
printed information from any label.
||* "How much did it cost?" "$29,000" "OK, what's the
current value?" "somewhere between $-350 and $65,000
depending what experiments the reviewers ask for" "can
you give me a solid figure" "not really" "surely there's a
reasonable estimate, what's it worth on the open
market?" "The global market is me, I'll take it off your
hands for -$350, tell you what I'll throw in shipping and I
can test it for another $500" "I'll put down $0 and send
you a tag" "I wouldn't do that, very adhesive sensitive is
the photon alignment in the 1989 Photicon XL1201b, you
can end up with 2nd harmonic peaks, that was the main
problem when Photicon were acquired by Perkin Elmer,
Literally just the rebadging made it un-calibratable.... I
mean I could go on"