Holding sparge temp ?

[Fil]

+1 for the 30a switching controller TMH linked to, fwiw im using one to control our fridge since its own thermostat died turning the thing into a 2nd freezer they can heat or cool but not both like the stc1000.

pid wise ive read conflicting reports regarding the rex models, Auber make the good uns but they are more expensive, the sestos one i use is a close copy of the auber but is like the rex a far east rip off.. Unlike the simple controller TMH linked to a pid is a way more complicated beast, and will probably need a sit down and manual read before each use (thats what i need to do anyway)

One thing with a hlt heated with any controller is that its possible for the liquor to be at the correct temp at the level the probe reads but can be a higher temperature above and a lower temperature below, So its a Good idea to give the HLT a good stir to mix it all up to normalise the temperature before sparging, It may only be a problem if the tank is left to sit for a while, but Im not the only one who has come a cropper due to this feature of a temp controlled hlt

[daf]

Aren't you concerned about tannins? Putting 75+ dog water on that lovely mash?

[MarkO'B]

I have the simmestat linked to previously in the post, that has been more than adequate when I have brewed with that. Now, I'm not and expert, nor am I going to spout like one.

The point of this for me is brewing beer that I like, am happy with, to a standard that is such, I don't feel the need to be purchasing from the supermarket. I also see that everyone brews with differing equipment, various distances between tanks, methods of transferring liquid and heating it. People use what they have around and adapt things for their specific purpose. People have differing levels of experience and obviously, what one person is happy with, there are those who expect more. So, not only are there so many variables between the systems people use, there are variables about how they use it and what they expect. Chances are that the same brew will be different to some extent each time and between different people brewing.

With all that in mind, why is electronic management of sparge temp so important? Am I missing something here? I know I have been happy with results without.

[far9410]

I'll be ripping apart from electrim boiler soon so you could have the simmerstat off that if you want. But it's rubbish which is why I've moved over to an PID based solution. STC-1000 with an additional relay would do the job nicely even if the temp would fluctuate more than with a PID based system. The simmerstat was just fundamentally unstable- hence my first AG being tannin city when the previously stable sparge temp suddenly went up by 10-15 degrees.

You could go down the REX route for a PID but they're pretty much all fakes and some are better than others. Some of the SSR REXs are in fact relayed REXs so I'd suggest paying a bit more if you're going PID and go for a SESTO or even an Auber.

The difference between a STC-1000 and a proper PID is the difference between someone slowly turning down a dimmer switch to keep a constant temperature (PID) and someone turning the heat on and off every few 20-30 seconds to keep it at a given temperature (STC type on/off control).

sure but if the parameters on stc are set wide enough, then it doesn't keep switching in and out?

[Piscator]

Aren't you concerned about tannins? Putting 75+ dog water on that lovely mash?

No - it doesn't stay up there for long enough, just enough to achieve mash out (tannins aren't really a problem until the grain gets nearer 80C) remember the temperature is falling slowly during the sparge as well (unless you have a whizzy heater ) Unless you measure the temperature that the grain bed is achieving during the sparge worrying about the temperature of the liquor is academic.

[daf]

What's the science behind 'mash out' again?

[Piscator]

What's the science behind 'mash out' again?

In a nutshell............. traditional single infusion mashing is intended to produce wort which contains about 75% maltose and 25% dextrins (NB dextrins are a group of sugars and not the same thing as dextrose which is a single sugar). This 25% dextrin content is important as these are less fermentable and remain in the beer providing body and mouthfeel (they do not contribute much in the way of sweetness though which is a bit of a myth that gets propogated). Dextrins are also important for developing condition as the yeast can ferment some of them but it takes longer, this is very important for the secondary fermentation in cask conditioned ales in particular where no priming sugars are added.

The amylase enzymes which convert the starch into dextrins and dextrins into maltose do not have an "off" switch and if left to their own devices will continue to change the ratio of dextrins:maltose - in theory "mash out" raises the temperature to a point where they are inactivated at the start of the sparge therefore keeping the ratio of sugars where it is intended without taking it high enough to extract excessive amounts of tannins. If the ratio of sugars is changed unfavourably the result can be a thin/dry beer.

Like many of these things there are believers and un-believers.... there are even some who have experimented with cold sparging

Other factors such as not using properly treated sparge liquor and over sparging carry a bigger potential for extracting tannins in my opinion.

Cheers
Steve

[daf]

Thanks for that. Sounds like a lot of mither!