[Homeroast] Vac-Pot Temp

Seth Grandeau grandeau at gmail.com
Thu Mar 22 07:32:02 CDT 2012


I like to get the water boiling on the bottom, without the funnel in
place.  Once I get a good boil going, i dial it down to low (simmer is too
low on my stove) and add funnel with glass rod and coffee.  The water
starts rising immediately and I've measured the temp, it's always between
200 and 205.

On Mon, Mar 19, 2012 at 12:35 PM, John Stewart <johns_webmail at yahoo.com>wrote:

> I have the same observation on temperature.  It takes a bit more time and
> patience to get the temperature on the vacuum pot over 190.  I usually
> stick a thermometer in the top to track the temperature.
>
> As to the other thread on stalling.  I use a yama pot and cory glass rod.
> Getting the temperature on top up to 190-195 means that steam is bubbling
> through the top for a couple of minutes.  I'm speculating that brewing to
> the 195ish temperature does a couple of things.  It increases the brewing
> temperature, increases the brewing time, and it increases the agitation in
> the brewing chamber.  (I'm not averse to stirring the top a couple of
> times.)  I'm thinking that the increase in brewing time and agitation makes
> the process less likely to stall.  My speculation is that the increased
> time more fully expands the coffee granules and the agitation helps keep
> the coffee from settling together.  One other note that may effect things
> here is the rate and method of cooling.  I use a gas stove, and once I hit
> the target temperature, I remove the vacuum pot from the burner and place
> it on a pot holder.  My thought here is that I want the cooling process
>  to begin quickly - as opposed to leaving the vacuum pot on a hot
> surface.  I could see that leaving the brewer on a hot electric coil for
> instance, would allow the grounds to settle fully before the bottom is cool
> enough to draw the coffee down.
>
> John
>
>
> ________________________________
>  From: Doug Hoople <doughoople at gmail.com>
> To: "A list to discuss home coffee roasting. There are rules for this
> list, available at http://www.sweetmarias.com/maillistinfo.html" <
> homeroast at lists.sweetmariascoffee.com>
> Sent: Sunday, March 18, 2012 2:19 PM
> Subject: Re: [Homeroast] Vac-Pot Temp
>
> Hi John,
>
> No scientist here, but I have measured the water temperatures in the vacpot
> funnel, and, in my experience, you're going to have a hard time getting the
> water temperature any higher than 205F under any circumstances.
>
> My method is to take water out of a hot water kettle just off boil, pour it
> into the pot (lower portion) and place the pot on a hot stove burner, let
> the water rise into the funnel, and then dumping the grounds into the
> funnel.  Because the rise is governed by temperature differences and not by
> absolute temperatures, you can get water to rise into the funnel when it's
> as cool as 155F or so.
>
> Even taking water just off boil (just slightly less than 213F), the first
> bit of water rising into the cold funnel is somewhere around 175F (!).  The
> cold funnel continues to act as a heat sink, and by the time all the water
> has risen to the top, I get readings around 195F.  The grounds are also
> cold and will cool the water in the funnel briefly as well. The water temp
> might rise another 5 degrees during the 2-minute steep time, and maxes out
> around 200F or so.
>
> I've also recommended the 'burst of heat' just before drawdown (to prevent
> delays and stalls), and that burst of heat, lasting no more than about 5
> seconds, doesn't raise the water temperature measureably.
>
> You can get higher water temps by letting the water bubble at idle in the
> funnel for a while before dropping in the grounds, but if you drop your
> grounds in as soon as the water's at the top, your temperature curve should
> be mostly as described above.  If you start with the grounds already in
> your funnel, there is probably no difference in temperatures whatsoever.
>
> I've found that coffee brewed in the 195-200F range is just about right.
> It seems that, the cooler the water, the less bitter the coffee.  Even
> when the temps creep up above into the 200-205F range, it seems that the
> coffee flavor takes a bitterness hit, so cooler is better IMHO.
>
> But no, I don't think there's a problem with overheated water in a vacpot.
> .
>
> Thanks.
> Doug
>
> On Mon, Mar 19, 2012 at 8:40 AM, John M. Howison <johnmhowison at gmail.com
> >wrote:
>
> > IMHO, my Vac-pot with a glass rod rather than cloth brews coffee as
> > good as it gets.  One of my kibitzers opines that during the minute
> > that the water on the grounds is bubbling it exceeds 212 degrees, with
> > heated air and water rising under pressure.  Said kibitzer compares
> > the situation to that of liquid in a pressure cooker, where
> > temperatures exceed 212.  I disagree, because water at 212 degrees
> > does not produce great coffee in a French Press or an Aeropress.  I
> > allow for the possibility that toward the end of the "fill" very hot
> > water may be arriving, but does not necessarily raise the whole potful
> > to 212.   Scientists please comment.
> >
> > --
> > Contra muros, mater rubicolla
> >
> > _______________________________________________
> > Homeroast mailing list
> > Homeroast at lists.sweetmariascoffee.com
> >
> >
> http://lists.sweetmariascoffee.com/mailman/listinfo/homeroast_lists.sweetmariascoffee.com
> > <a href="http://www.sweetmariascoffee.com/forum/">Sweet Maria's
> Forum</a>
> > <a href="http://www.sweetmarias.com/library">Our new Coffee Library</a>
> >
> _______________________________________________
> Homeroast mailing list
> Homeroast at lists.sweetmariascoffee.com
>
> http://lists.sweetmariascoffee.com/mailman/listinfo/homeroast_lists.sweetmariascoffee.com
> <a href="http://www.sweetmariascoffee.com/forum/">Sweet Maria's Forum</a>
> <a href="http://www.sweetmarias.com/library">Our new Coffee Library</a>
> _______________________________________________
> Homeroast mailing list
> Homeroast at lists.sweetmariascoffee.com
>
> http://lists.sweetmariascoffee.com/mailman/listinfo/homeroast_lists.sweetmariascoffee.com
> <a href="http://www.sweetmariascoffee.com/forum/">Sweet Maria's Forum</a>
> <a href="http://www.sweetmarias.com/library">Our new Coffee Library</a>
>


More information about the Homeroast mailing list