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Yeah I was about there. The spoons in that video made me chuckle
For me, I think the tricky bit is the lid.
For me, I think the tricky bit is the lid.
temeprature problem is negated because the reciculated wort is at the temperature shown on the user interface.
While agree I think it is a better situation than the wort over the sensor being in a situation where wort flow at that point could be stagnent. I think a better design would be one where the mash and the wort below the grain basket are stirred simiutaneously. So the drive shaft goes straight throught the bottom of grain basket and is fixed to a propeler to mix the wort below and help flow over the temp sensor... easy done.I would disagree, all you know is that is the temp at the probe point.
BM users have the same problem. Grain temp furthest from the probe can be quite different.
I have modified my AIO so that I can use the side whirlpool at the same time as recirculate. This means the wort is mixed over the sensor in the bottom of the vessel and also the wort in the deadspace between the malt pipe and vessel also gets mixed. With a further sensor testing the wort just before it goes onto the grains.While agree I think it is a better situation than the wort over the sensor being in a situation where wort flow at that point could be stagnent. I think a better design would be one where the mash and the wort below the grain basket are stirred simiutaneously. So the drive shaft goes straight throught the bottom of grain basket and is fixed to a propeler to mix the wort below and help flow over the temp sensor... easy done.
There is no other feasible place to stick the probe, it has to be at the bottom of the kettle and away from the elements. Even without any knowledge of the physics of heat diffusion through a mash, I think it is common sense there are hot and cold spots do we really think that a return pipe, which most brewers have choked down to half the flow to prevent the overflow pipe being brought into play will recirculate delivering an even temperature to the mash? Pigs arse.I think mash stirring is all fair and well but to be controversial I would prefer the stirrer in the bottom of the kettle where the wort exiting the malt pipe is. To my mine the problem with temperature differences is that the wort flowing over the temperature sensor is not giving a true reading for the temperature of the wort. There are dead spaces in these things that see wort flow totally different to the flow over the sensor. That wort leaves to be recirculated and it could be at an entirely different temperature to the wort flowing around the sensor. If the wort in the bottom of the kettle is properly homogeneous then to a large extent the temeprature problem is negated because the reciculated wort is at the temperature shown on the user interface. That is not of course to say that a stirred mash may not go some way to helping achieve that goal This has been shown to happen with the GZ gen 4 and they had to add a plate below the bottom grid to ensure the wort leaving the malt pipe flows over the temp sensor.
I know all of that thanks All you are pointing out is why these systems do not work Now you will find there is an entirley different thought amongst brewers who you these systems seeing the advantage of the system temperature being monitored from the top of the kettle where the recirculated wort enters the grain basket , see RAPT thermometer. The idea, which you ubdoubtedly know is to play the recirculation temperature off against the bottom sensor to ensure that temperature over shoots are minimised. Re the choking of the recirculation pipe. That is where users of this system are going wrong. You want that running flat out so that homogeneous wort is produced. Where a lot of brewers go wrong is over crushing their malt grains and causing a poor flow through the grain bed. Malt grains do not need to be powdered the only need to be just broken for starch conversion to take place. Every brewer has their own way of doing things but when it comes to brewers using these AIO systems it is not opinion but fact that the vast majority of users over crush their malt grains which restricts wort flow and invites temperature over shoots.There is no other feasible place to stick the probe, it has to be at the bottom of the kettle and away from the elements. Even without any knowledge of the physics of heat diffusion through a mash, I think it is common sense there are hot and cold spots do we really think that a return pipe, which most brewers have choked down to half the flow to prevent the overflow pipe being brought into play will recirculate delivering an even temperature to the mash? Pigs ****.
I mash full volume, so I have a very fluid mash, I can live with manually stirring my mash for 20 minutes while the starch converts.
But now I have had my interest tweaked for those doing a stiff mash using the preferable grain-to-liquor ratio when going into a sparge step.
Today making some bread, I use a KitchenAid to knead the dough, the perfect stirrer was right there in front of me an oscillating low-speed geared motor. Plenty of stand mixers on Market Place, but a shaft does have to reach the bottom of the grain basket, an easy fix.
But at the end of the day, a stir with a paddle every 5 minutes for twenty minutes will keep the mash temperature throughout the grain bed in equilibrium
But it isn't the difference in temperature from the top to the bottom. Throughout the grain bed, there are hot and cool spots all reading different temperatures. The only way to break these spots up is by stirring.I know all of that thanks All you are pointing out is why these systems do not work Now you will find there is an entirley different thought amongst brewers who you these systems seeing the advantage of the system temperature being monitored from the top of the kettle where the recirculated wort enters the grain basket , see RAPT thermometer. The idea, which you ubdoubtedly know is to play the recirculation temperature off against the bottom sensor to ensure that temperature over shoots are minimised. Re the choking of the recirculation pipe. That is where users of this system are going wrong. You want that running flat out so that homogeneous wort is produced. Where a lot of brewers go wrong is over crushing their malt grains and causing a poor flow through the grain bed. Malt grains do not need to be powdered the only need to be just broken for starch conversion to take place. Every brewer has their own way of doing things but when it comes to brewers using these AIO systems it is not opinion but fact the the vast majority of users over crush their malt grains which restricts wort flow and invites temperature over shoots.
In an ideal situation the grain bed the wort below the grain bed and the recirculated wort entering the grain bed it would be isothermal. This is not possible because of the reduced flow of recirculated wort through the grain bed and heat lose to the universe. The best way to gain an isothermal system is to increase the flow rate and pump the wort at as high a rate as is possible. By doing this the wort below the grain bed has less time to heat beyond the desired temperature, the wort travelling through the grain bed has less time to lose heat to the universe and the system has a more stable temperature gradient hotter to colder. The best way to get near that situation is to not over crush the malted grains and thus encourage a fast flow rate of recirculated wort through the grain bed. Having worked in scientific research for 40years I have a little knowledge of how thermodynamics work... energy only travels from a hotter to a colderBut it isn't the difference in temperature from the top to the bottom. Throughout the grain bed, there are hot and cool spots all reading different temperatures. The only way to break these spots up is by stirring.
The process of heat diffusion through grain mash involves the transfer of thermal energy from the hotter areas of the mash to the cooler areas. This occurs due to the random movement of molecules, where hotter molecules collide with cooler ones, transferring energy and eventually reaching a state of equilibrium.
To speed up the process of heat diffusion in grain mash, the mash can be stirred or agitated, which helps to distribute the thermal energy more evenly. Additionally, increasing the temperature of the mash or decreasing the density of the grains can also help to speed up the diffusion process.
Reference: file:///C:/Users/Owner/Downloads/Heat%20diffusion%20through%20grain%20mash%20to%20reach%20equilibrium.html
Very well said, consumers are gullible, and the more marketing the easier to reel them in. The ones being looked at by the OP are not a set and forget SVB's they have to be worked by the operator to extract the best out of them.
Over here in Australia it is illegal not to carry spare parts for the product being sold I would have thought it would be a similar law in the UK.
Should bonded elements burn out the replacement is the kettle and the elements then transfer the pump, circuit board and screen over.
Magical Pancake who is a forum member made a video of replacing the element.
The wash of water running over the element is just another gimmick, the scorching happens not in the boil but in the mash, mashing at a lower wattage eliminates scorching. The turbulence of the boil prevents sugars from sticking to the bottom plate.
Stirring regularly during the mash maintains the temperature, doesn't matter if it is a PID or analog temperature controller. Whatever unit is purchased will take the effort on the user's part to get the best out of it.
Well I have the Guten and Hop Cat virtually the same but both don't have the low Watt density that Keg Land claims stops burning above the elements. I mash on 1700 Watts and get no scorching whatsoever."The scorching happens not in the boil but in the mash" is certainly not what happened on my first use of BZ gen 4 35l. My first brew ever, destined to go down the sink.
A Weisenbock, with 7.5kg malts, 50% wheat malt, in 23l mash.
Virtually stuck step mash, extremely slow recirculation, even with lots of stirring. During boil, built in sensor was showing 115°C, then got an 'overheat shutdown' for a minute.
On draining found most of bottom covered with thick burnt on layer, almost up to bottom of diffuser plate. And a smokey tasting wort, that was very astringent.
It seems all the stirring let flours through. And with the slow recirculation, these largely settled on the base, rather than being recirculated and caught back in the grain bed.
On second brew (Budvar, no wheat) recircirculation was fine at max flow.
Before boil, I'd drained off the mash to check the base was clear, and found there were just a few small patches of flour. But, as it was a lager, I rinsed these off to be sure the flour didn't scorch.
This time, initial recircilulation (to 40 minutes) was done around outside of the malt pipe, rather than through the malt. Acheived by sticking the recirculation pipe through one of the lifting holes. The malt was then being heated from all round, as well as from below, and putting bubble wrap over the lid reduced heat loss from it's top.
Using the Rapt probe thermometer, about my favourite improvement to the BZ, showed how effective 'outside' recirculation was. Over the first 10 minutes, with no recirculation, temperature near top centre of bed had dropped 1°C. After starting side circulation, top-centre temperature started climbing around 0.5 °C a minute.
When using a Rapt probe, the BZ controls the real mash temperature much better. The 'differential override' setting, sets how much higher the bottom temperature (measured by internal sensor) can go above the set temp.
With diff set to 5°C, and say a 60°C target, you can see how quickly the base temperature overshoots the target, even at 40% power, then oscillates between 59°C and around 65°C. And how slowly, depending on recirculation rate and diff setting, the real temperature slowly climbs to the target.
The probe thermometer doesn't help much during sparge; boil; or cooling, and would be in the way. But once probe is powered down, the BZ switches back to using its internal sensor.
I'd been wondering if the stuck Weisenbock mash, might have been from starting recirculation through bed too early. Rather than the (notorious) wheat malt being the problem (despite 10% oat husks).
Same grains re-ordered, so hope to find out soon.
I've the heat exchange (diverter) plate fitted in my BZ gen4, a solid plate half way between false bottom and base leaving gap around outer edge. It diverts the recirculated wort so it then all flows right across the bottom (to central drain hole) for even heating.Well I have the Guten and Hop Cat virtually the same but both don't have the low Watt density that Keg Land claims stops burning above the elements. I mash on 1700 Watts and get no scorching whatsoever.
Very surprising that the scorching occurred during the boil as the turbulence coming off the area of the elements would/should prevent any scorching.
Why was the pump pressure so low? All the SVB's use the same pump, I open mine to full bore even with adjuncts in the mash, and stir for 20 minutes by which time conversion from starch to sugar is about complete.
Rapt probe is just puffery, same with a lot of claims made to sell a product. If it was possible to put half a dozen probes into the mash you could more than likely get half a dozen different readings. The pump recirculation doesn't help in bringing the temperature to equilibrium the only way is stirring or other agitation. What the pump does is dump all the small pieces of grain back on top of the grain bed.
As the conversion is completed (using malts with high diastatic power in 20-30 minutes) the grain bed can settle, the pump carrying on dumping all the loose bits on the top of the grain bed.
The wheat malt, was it crushed grain, or pre-gelatinised malted wheat flakes? When I have made wheat beer I have used the flaked wheat malt, which makes life a lot easier.
I don't have a mill, and buy all my malts coarse crushed, from the malt miller. And haven't yet found a supplier that will supply 'just cracked'. Can anyone suggest a place?I know I am repeating what I said earlier but I will. One of the biggest mistakes brewers using AIO systems is crushing the malt grains over fine. This leads to the production of too fine a grist with too great a proportion of flour which in turn greatly hinders the flow of wort through the compacted grain bed. Something this system of brewing requires is a high flow rate of recirculated wort. A high flow rate ensures that the top to bottom temerature gradient is at a minimum and that a good rate of extraction of sugars from the malt grains is achieved.
Timothy Taylor brewers mash with grains that have only just been cracked when they make their beers. Now we know the are professional brewers are better placed to mix their mash and then sparge but the same principal applies to AIO home brewing. A lighter crush allows faster recirculation of wort which in turn elutes more of the sugars from the mashing grains and greatly helps termperature stability in the system. With reference to the wheat beer, this is the reason that high wheat content grain bills are a nightmare in these AIO's the whet flour just bungs the grain bed and the work struggles to flow through it. Here endith this sermon brethren
I suspect that the crush you get from the malt miller will be suitable for an AIO but it will still put efficiency ahead of wort flow. I crush my malt grain at 1.4 mm sometimes a bit more .Wheat malt grains crushed at that are fine too in my experience but then again I never go more than 40% wheat in my mash to prevent sticking. Crisp Maltings pre crushed malt supplied to some brewers is done at 1.6 mm according to a video I watched .I don't have a mill, and buy all my malts coarse crushed, from the malt miller. And haven't yet found a supplier that will supply 'just cracked'. Can anyone suggest a place?
Only had a stuck mash when doing wheat beer, and the wheat malt crush looks no different to all the others.
No need to change the recipe, you can still mash at your saccharification temperature but I would be removing the top plate and stirring while the starches convert. I would say most of the flour in your mash would be from the wheat malt.I've the heat exchange (diverter) plate fitted in my BZ gen4, a solid plate half way between false bottom and base leaving gap around outer edge. It diverts the recirculated wort so it then all flows right across the bottom (to central drain hole) for even heating.
Under the plate its just a 6mm gap, the charred flour filled the height with just a few channels from pump recirculation, so I guess boiling couldn't lift it.
I have my doubts about the plate being a good idea during boil, and posted the question on forums before buying, but everyone seemed happy.
A previous stuck wheat beer in BZ3.1, had just as much flour below, but hadn't scorched.
During mash, if pump was opened more than just a trickle, level in malt pipe rose - level outside malt pipe fell till air underneath - air in pump - no recirculation.
You could get a dozen different probe temperatures, from different points in the malt, but every one would show the working mash temperature more accurately than any built in probe located by the heater.
Supplier I use, TMM, only does un-malted rolled wheat flakes. Those make 7% of the Weisenbock grain bill, and malted wheat grains 43%, so could try upping unmalted percentage a bit.
Other brew suppliers have GEB 'Chit wheat malt flakes' which are only barely malted, that I guess wouldn't convert well.
Health food stores do 'malted and toasted wheat flakes' but don't give figures for diastatic power or colour.
I suspect that the crush you get from the malt miller will be suitable for an AIO but it will still put efficiency ahead of wort flow. I crush my malt grain at 1.4 mm sometimes a bit more .Wheat malt grains crushed at that are fine too in my experience but then again I never go more than 40% wheat in my mash to prevent sticking. Crisp Maltings pre crushed malt supplied to some brewers is done at 1.6 mm according to a video I watched .
The malt miller do a grist box separator test, to find crush settings for giving consistent coarse : fine : flour ratios across grains.
The light and dark wheat malt bags from TMM, looked to have same amount of flour as their barley malts I used in the recipe.
Good video from a few years back.
I feel the wheat issues mainly come from it being a huskless malt (like naked barley), and having higher gum levels.
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