ajdelange

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Join Date:

08-06-2010

Last Activity:

09-03-2015 1:44 AM

Likes Given: 33

1079 Likes on 845 Posts 

    ABOUT ME

  • Retired
  • Baroque, early Classical
  • BURP, AHA, ASBC, MBAA
  • Male
  • Married
  • McLean/Ogden
  • Virginia/Quebec

LATEST ACTIVITY

  • Posted in thread: Good Deal on Ph Meter? $11 shipped! on 08-31-2015 at 03:34 PM
    I wouldn't trust the pH meters you use in the lower level chem labs, so why do you even bother?
    Besides, I hear each of you saying these meters are junk but no one of you have tested them
    against the ...

  • Posted in thread: Good Deal on Ph Meter? $11 shipped! on 08-31-2015 at 01:43 PM
    What I'm saying is that 0.1 +/- 0.1 pH accuracy is probably way more precise than taste buds. I
    don't know this as fact, but I'm willing to give it a shot to find out.How will you do that
    with a meter...

  • Posted in thread: another water report need help reading on 08-31-2015 at 01:27 PM
    I think you could enter 21 mg/L calcium and alkalinity of 50 ppm and represent your water
    pretty accurately in a spreadsheet. You can also go with the 1/8 - 1/4 gram per liter calcium
    chloride additio...

  • Posted in thread: Proximity of SSRs on 08-31-2015 at 01:19 PM
    It's not the mass of the metal that is significant but its thermal impedance to ambient. The
    latter is inversely proportional to surface area and airflow over it. If the box is big enough
    and subject ...

  • Posted in thread: 50A, 3 elements - Interlock two of them? on 08-31-2015 at 12:50 PM
    Easy to draw, lots of work to wire.Wow!!! This is about as simple as it gets and is based on
    the standard Start/Stop pushbuttonb station. Not hard to wire at all.1)Control power + bus to
    Start PB2)St...

  • Posted in thread: 50A, 3 elements - Interlock two of them? on 08-30-2015 at 05:57 PM
    Should be simple enough to do with a couple of relays each with 2 NO and 2 NC contacts per the
    diagram below. The NO contact not shown for each is used to operate the contactor or relay that
    controls ...

  • Posted in thread: Stratification within volume gauge on 08-30-2015 at 01:18 PM
    Just wait about a month or 2 and diffusion will remove the stratification.If it bothers you
    just blow into the top of the gauge or use N2 or CO2 or an air compressor to force the liquid
    in the gauge b...

  • Posted in thread: "Understanding Efficiency" on Braukaiser on 08-30-2015 at 11:40 AM
    ... funny thing: if you input 50% moisture, the SG doesn't change at all. That shakes my
    confidence in it. I'll just make a spreadsheet and input the grain bill and their info by
    hand.I always trust ...

  • Posted in thread: Good Deal on Ph Meter? $11 shipped! on 08-30-2015 at 03:21 AM
    This is clearly not for the 10/10ths brewer. The one who obsesses over every minute detail. I
    judge a brewer by the product he puts out, not the level of detail he puts into the process.
    Me too but i...

  • Posted in thread: "Understanding Efficiency" on Braukaiser on 08-30-2015 at 02:58 AM
    Ah, yes. I think that's correct. But somehow they come up with a gravity that implies greater
    than 80% extraction and that just doesn't happen in the real world. Sometimes you will see 81
    or 82% for a...

1 COMMENTS
Posted: 
February 8, 2014  •  08:08 AM
Yeast starters generally need to be stepped up to a size appropriate for 10 gal batch pitching. But I've been researching the reason for this. It seems to me, that if the yeast needs can be anticipated and met for the whole starter size, then this step-up procedure could be eliminated. The most obvious delta (to me) across the fermentation is pH. Internally, yeast maintain pH at 5.0-5.8. Dissolved CO2, excreted acids, and cell H+ transport continously increase H+ concentration, decreasing pH. There needs to be a pH delta across the cell wall for maltose influx. So this is why yeast act to decrease pH in external medium. But they don't appear to be able to shut that process off (at least, completely) and so can acidify mediums that aren't well buffered right down and out of their operating window. Looks like best pH is mid-4's to 5.0 or so. Now, pitching a starter with too little yeast means that they can't quickly acidify the wort down to optimum pH levels. And then, even if they can, such a large amount of growth causes over-acidificaiton and floccing before full attenuation. Since this is a starter and we intend to decant the 'beer' before pitching, can't we introduce a buffer into the wort before fermentation? The buffer would hold pH around 4.5-5.0. The yeast would be presented with optimum pH from start to finish, ensuring full attenuation with any size starter, with any size innoculation. What think ye? Any recommendations for acid-salt-alkaline combinations for buffers?
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