mash run false bottom help

[HTH1975]

I'm nearly there with my all-grain setup, but it seems that the grains may end up scorched without a false bottom to raise the grains up from the heat source.

I've got an electric Brewpacs 30 litre kettle with a filter on the outlet tap to stop blockages. I'm wanting to mash in this kettle but I'm a little confused on the false bottom options. There seems to be two options: with or without a tube from the centre of the false bottom to the outlet tap.

What are the pros/cons?

Many thanks for any advice.

 

[Brew_Meister_General]

I'm nearly there with my all-grain setup, but it seems that the grains may end up scorched without a false bottom to raise the grains up from the heat source.

I've got an electric Brewpacs 30 litre kettle with a filter on the outlet tap to stop blockages. I'm wanting to mash in this kettle but I'm a little confused on the false bottom options. There seems to be two options: with or without a tube from the centre of the false bottom to the outlet tap.

What are the pros/cons?

Many thanks for any advice.

If you're using a kettle for a mash tun then a false bottom is essential and ideal for fly sparging, with this set-up you'll be hitting 80% efficiency although you might need to get a boiler jacket for insulation and wrap it to the outside using some bungees.

Depending on the diameter of the boiler you might be able to purchase a domed false bottom. The biggest one I could of got was 30cm whereas the internal diameter of my boiler is 33.5cm, which might not sound like a lot but that extra 3.5cm is actually 20% of the surface area, so I thought it would be more worthwhile getting a flat bottom (i.e. the ones held up on a stand) to create more consistency with the rinsing of the grains. You can get certain brew shop to make one for you, it will be expensive but would pay off eventually.

In the case of a domed false bottom it'll be best to connect it to the ball valve using copper piping (rather than a silicone tube) for when you stir the mash.

An additional idea is to use a solar pump (which have a 1/2" inlet that you can screw right into the ball valve) to recirculate the water, thus pulling the hot water from the bottom and putting it in the top and creating much more consistency in temperature for when you do multi-rest mashes, not to mention promoting clarity.

 

[HTH1975]

Thanks for the answer - definitely getting there now. Do you have a link to the type of false bottom that you're suggesting?

 

[Brew_Meister_General]

Thanks for the answer - definitely getting there now. Do you have a link to the type of false bottom that you're suggesting?

Well this is an example of a not-so-good one made at home, I don't actually know what homebrew websites do custom false bottoms although I'm sure there are many you could order from with a bit of online searching.

Depending on the diameter of your mash kettle a custom cut one - although expensive - may be the best choice. Although you can always google to see if there are domed false bottoms already available in a suitable size as I imagine there are a number of brands that do a variety of them.

When comparing the ones with and the ones without a tube to the outlet tap, i.e. the ones below and the ones above the outlet, the ones without a tube (above outlet) initially gives you less volume to work with as there is a greater gap underneath the false bottom. This however can be solved with a solar pump which will then put all the water to use and not just whats on top.

I prefer them as it means there is no copper pipe in the way of my mash, in other words I'm just going that extra length is trying to create as much evenness as possible in the soaking of the grains despite how minor it may be. It wouldn't be deemed as worthwhile when considering all the extra space it would requires to hold the false bottom above the outlet, but this can be resolved by a solar pump which has other benefits as well.

 

[HTH1975]

Thanks for that explanation - very thorough. Looks like I need a solar pump as well now - this is getting expensive, ha ha :0)

 

[jschein]

Custom false bottoms here; http://www.norcalbrewingsolutions.com/store/index.html

 

[RM-MN]

Thanks for that explanation - very thorough. Looks like I need a solar pump as well now - this is getting expensive, ha ha :0)

It doesn't need to become expensive, The choice of the route to beer is up to you and once you have chosen a certain route the expense is rather set. You don't have to maintain that exact route though and can reduce the expense if you choose. It's up to you what you want to spend. You might look at doing BIAB as a simple, inexpensive way to make beer. You won't have to change much to go that route and your equipment will still be the same so you can go back to the route you originally planned with the only extra expense being the bag which can be a paint strainer bag for less than $5.

 

[Brew_Meister_General]

Thanks for that explanation - very thorough. Looks like I need a solar pump as well now - this is getting expensive, ha ha :0)

I agree with RM in that we've just gone the expensive route by implementing a mash kettle but that was always my incentive, to think in the long term and get all the best equipment even though it means spending quite a bit more.

Which is why I have a single vessel HERMs systems to perform multi-rest mashes in an ideal shaped mash tun with a fly sparge and a perfectly flat false bottom, simply to get the most out of my grains for as long as the equipment will last.

 

[HTH1975]

I can justify maybe another £100 tops at present to finish off my brewing setup. From what I can see, a false bottom is going to run me around £50-60 and about £15 for a solar pump. I'd rather get my setup right from the start and get the best efficiency, so I'm happy to spend a bit extra.

From what I can gather, by recirculating the wort in the mash tun, this will give better efficiency and a clearer wort. Does that sound about right?

 

[RM-MN]

I can justify maybe another £100 tops at present to finish off my brewing setup. From what I can see, a false bottom is going to run me around £50-60 and about £15 for a solar pump. I'd rather get my setup right from the start and get the best efficiency, so I'm happy to spend a bit extra.

From what I can gather, by recirculating the wort in the mash tun, this will give better efficiency and a clearer wort. Does that sound about right?

I've been getting between 85 and 90% efficiency with my BIAB. Do you expect to do better with your more expensive system? Will it make better beer?

Yes, recirculating the wort in the mash tun will give you clearer wort. However, clearer wort does not ensure clearer beer. Those of us who do BIAB have some terribly cloudy wort but it turns out clear beer anyway. Don't be misled by those who say you need clear wort. All you really need is to separate the grains from the wort.

 

[HTH1975]

I'm glad you've raised that issue, as I've been wondering why everyone doesn't do BITB - it seems more straightforward and easier to separate the grains from the wort. What exactly is the benefit to mashing with the grains loose? (i.e. without a bag).

I got crushed grains as I'd read it was better for BITB efficiency, however for a mash tun would this not block things up? It seems that I might have no option but to do BITB for this batch.

Another thing I'm wondering is why BITB instructions say to mash with the full volume of water. Why do this rather than steeping the grains, then sparge in the bag???

 

[wilserbrewer]

IMO you really don't NEED a false bottom, and could brew with that kettle as is. Rather than adding heat during the mash, simply wrap the pot in a blanket to maintain a steady temp.

Heat to strike temp and shut off element. Add grain and insulate kettle. You may lose a few degrees, but it's not a deal breaker by any means. You could do full volume, BIAB, batch sparge and even cold water sparge. Many ways to get nice beer.

 

[HTH1975]

I think I might just give it a shot without the false bottom - what the hell :0)

Speaking of strike temperature - should I hear the water a few degrees above the temperature I want to mash at? I'd imagine that adding grains will drop the water temperature by 5C easy.

 

[wilserbrewer]

5c sounds a little high for full volume. Rackers.org has a handy mash temp calculator. You could likely charge the element with a mash in the kettle as long as you stir constantly to avoid scorching if you need to raise a degree or two.

 

[Brew_Meister_General]

I can justify maybe another £100 tops at present to finish off my brewing setup. From what I can see, a false bottom is going to run me around £50-60 and about £15 for a solar pump. I'd rather get my setup right from the start and get the best efficiency, so I'm happy to spend a bit extra.

From what I can gather, by recirculating the wort in the mash tun, this will give better efficiency and a clearer wort. Does that sound about right?

Oh cool you're based in the UK as well then, if you live in London then you can find everything you need to know about your water chemistry on the Thames Water website. You can expect it to be medium-hard with 200-300 bicarbonates means its better suited for darker beers, you can use the Total Hardness to work out the calcium, magnesium and bicarbonate content.

The only 2 places I know that do a custom false bottom are Home Brew Builder and Hop and Grape, the latter of which do up to 32cm in diameter for £40. Any wider than that means an extra £10.

That being said, the other gentlemen may very well be right about the BIAB being the better choice. It is something I have no experience of so it'll be worthwhile looking into if it means you can hit 85%+ efficiency. I think the only other thing it would require is a roller mill, the advantage being that you can store (whole) grains for longer periods. It'll also mean you'll never have a stuck mash like when dealing with high levels of wheat.

You're right in saying that you should heat your water 3-5c+ higher before adding the grain, if you go on Brewers Friend they have a bunch of calculators. The advantage of a mash kettle is that you can do multi-rest much more simply, if you do intend to do a single-infusion then the solar pump won't be of much use, although I would say go the extra mile and do a rest at 40c before moving up to 60-70c and tailoring your beer as such, not to mention heating to 77c for the mash out.

This is the solar pump I bought which can actually just be plugged in: http://www.amazon.co.uk/dp/B00QA8D6XE/?tag=skimlinks_replacement-20

 

[Brew_Meister_General]

Another thing I'm wondering is why BITB instructions say to mash with the full volume of water. Why do this rather than steeping the grains, then sparge in the bag???

As the enzymes and sugars have more water/space to operate in once they leave the grain. Research (thats findable on wiki) has shown that a thinner mash (of say 5 litres per kilogram) improves efficiency, although you'll have to balance that out with the fly sparge water in order to find that ideal equilibrium.

From what I've read if you have 5l/kg (= 2 qt/lb) then you only need half as much water for the fly sparge, if its 3.75l/kg (= 1.25 qt/lb) then I think its the same amount.

 

[HTH1975]

Thanks for that advice - spot on :0)

I'm actually in Thirsk, North Yorkshire. The water report says we have hard water with 93mg/l of calcium. What other things should I look for specifically in my water report so I can tailor things?

Can you also explain the multi-rest mash technique further please? All I've read on this is that it will increase malty flavours and improve efficiency. I'm happy to go the extra mile if I'll get a better end result.

 

[Brew_Meister_General]

the multi-rest mash technique further please? All I've read on this is that it will increase malty flavours and improve efficiency. I'm happy to go the extra mile if I'll get a better end result.

Theres quite to bit to read on multi-rests just because of what different temperatures promotes in terms of various enzymes but most importantly theres 5 rests.

40c - Liquefying (?) rest (beta-glucanase and limit-dextrinase enzymes)
58c - Protein rest (peptidase and proteinase)
60c - Beta rest
70c - Alpha rest
77c - Mash out

From what I've read a rest at 40c for 30 min will improve your efficiency 'by a couple points' whilst a rest at 60c and 70c for varying lengths of time (ex. 20 min beta, 40 min alpha) will tailor the beer.

Beta enzymes produce only maltose meaning you would end up with more attenuation, producing a beer with more alcohol but less body.

Alpha enzymes produce sugars of various lengths, some fermentable, some unfermentable, meaning you would get less attenuation.

A protein rest is only useful for when using under-modified malts which might only be the case when making old-fashioned, German beers.

However I advocate 58c instead of the traditional 50c as at 58c the proteinase enzyme which supposedly breaks down unwanted 'large' proteins into wanted 'medium' proteins is at its peak temperature. The peptidase enyzme breaks down medium proteins into small proteins which the yeast use as nutrition but medium proteins are most important in providing the beer with body and head retention. For those reasons a rest at 58c should be beneficial when using malts that are high in proteins (wheat, flaked barley) although this is just a theory.

The mash out at 77c is just good for halting enzyme activity once all the starch are converted which you can test with iodine.

As always John Palmer is a good place to start although I'm sure theres plenty of articles on it online.

Standard Multi-Rest:

40c 30 min
60c 30 min
70c 30 min
77c

Although to be honest it always take me longer than 60 minutes to fully convert all the starch so for me it might be something like:

40c 30 min
60c 20 min
70c 70 min
77c

 

[Brew_Meister_General]

Thanks for that advice - spot on :0)

I'm actually in Thirsk, North Yorkshire. The water report says we have hard water with 93mg/l of calcium. What other things should I look for specifically in my water report so I can tailor things?

Altogether theres...

Calcium (50-250 ppm)
Bicaronates
Sulphate
Chloride (max 100 ppm)
Sodium (70 - 150 ppm)

Calcium and bicardonate are most important, calcium simply because its the backbone of the beer so to speak, 93 mg is a great amount, not too much, not too little. As you add certain salts such as calcium sulphate then it will increase by a small amount, if its too high, approaching 200 ppm say, then it would produce a metallic taste although I don't think you'll ever have to worry about that.

Bicarbonates are basically the alkalinity of your water. Historically when a brewers water was higher in bicarbonates they would of had to use darker malts which are more acidic to bring the pH down to the ideal 5.2. Nowadays we can just use phosphoric acid so in a sense you don't actually need to know as you can find out its alkalinity as you brew. Last time my wort dropped to 5.6 after adding malts so now I would just add a bit before and a bit after. This applies so the sparge water as well which would have a pH of 5.2.

In terms of tailoring theres sodium, chloride and sulphate. Sulphate is known to accentuate the bitterness or hop characteristics whereas chloride is known is accentuate the sweetness or malt characteristics. Sodium is known to create a rounder, fuller and sweeter tasting experience, its said to be best between 70 - 150 ppm although too much produces a salty flavour.

There are 3 salts you can use to configure you beer in this way: calcium chloride, calcium sulphate (gypsum) and sodium chloride (sea salt).

Another significant factor with regards to sulphate and chloride is their ratio, when they have a 1:1 ratio the bitterness/sweetness is balanced but when it varies between 1.5:1 or even 2:1 then one factor will reside over the other which would be useful for brewing contrasting beers such as stouts and IPAs.

If you find these out via your local water report then you can put them into Brewers Friends water calculator and figure out how much of different salts to use. It will also take into consideration the balance between sulphate and chloride. Salts also lower the pH by a small amount.

 

[HTH1975]

^ Wow, what an amazing post. Very informative and easy to understand - 'water for dummies', if you will

 

[HTH1975]

Also, back on the false bottom subject, I bought a vented pie dish today which looks like it could work as a false bottom with a little modification.

This is my boiler with the heating element exposed and the hop strainer attached... View attachment ImageUploadedByHome Brew1451760131.260026.jpg

Below is the 'pie dish' I got today which covers the heating element, so I'm hoping that it will work as a false bottom by drilling the centre and attaching some pipe to the water outlet. View attachment ImageUploadedByHome Brew1451760356.953911.jpg

Sound doable?

 

[wilserbrewer]

Yes, it looks good. When adding heat you will need to distribute the heat throughout the mash either by stirring or pumping. From the looks of your vessel, is it plastic? It may hold heat well enough to not bother...jmo but it appears your taking the complicated path.

 

[HTH1975]

I agree it probably is the more complicated route, but it seems I'm almost there now, so might as well finish - I'm pig-headed, so I'd like to finish this approach. I may try a BITB at a later stage just for the hell of it.

The boiler is metal, with a kind of 'ceramic' finish. I'm going to test how well it holds temperature with some spare blankets wrapped around it and also over the top. Kind of like lagging a hot-water tank I suppose.

 

[HTH1975]

I tested my DIY false bottom today and it works fine. With a few blankets lagging the kettle, I only dropped 2C in an hour and 5C in 90 minutes. I teckon with a duvet added to this mix, I could lose even less heat. Or just turn the heating element on to bring the temperature back up.

 

[Brew_Meister_General]

I tested my DIY false bottom today and it works fine. With a few blankets lagging the kettle, I only dropped 2C in an hour and 5C in 90 minutes. I teckon with a duvet added to this mix, I could lose even less heat. Or just turn the heating element on to bring the temperature back up.

The main challenge is usually maintaining a consistent temperature throughout the mash but with a single infusion that shouldn't be a problem. You could also drill similar holes along the outside of the pie dish for drainage.

Back to the water chemistry, a level of 93 ppm of calcium indicates that you have a high level of bicarbonates (i.e. alkalinity) which means your water will be good for brewing amber and dark beers such as ESBs and porters etc. I image your bicarbonate level will vary between 150 - 300 ppm.

When it comes to brewing blonde and golden ales you would just need to add more phosphoric acid to the water, although you'll have to check if however much is needed will effect the flavour. In other words you won't be able to brew something as light as a pilsner without using distilled water, however pale ales with lots of hop flavours should be fine for masking any flavour the acid might produce.

 

[HTH1975]

Thanks for your post - that seems to tie in with what I've read so far on water. I do actually prefer darker, heavier beers. I'm not much of a lager or light beer fan.

As for my water, this is the full report...View attachment ImageUploadedByHome Brew1451869304.840808.jpgView attachment ImageUploadedByHome Brew1451869315.629844.jpgView attachment ImageUploadedByHome Brew1451869325.197704.jpg

At this point, it's worth asking how I calculate efficiency. I think this is important to know from the outset so I know I'm getting value from my grains.

 

[Brew_Meister_General]

Thanks for your post - that seems to tie in with what I've read so far on water. I do actually prefer darker, heavier beers. I'm not much of a lager or light beer fan.

As for my water, this is the full report...View attachment 327442View attachment 327443View attachment 327444

At this point, it's worth asking how I calculate efficiency. I think this is important to know from the outset so I know I'm getting value from my grains.

Calcium 67 (good)
Magnesium 15 (good)
Sodium 14 (low)
pH 7.33 (standard)

It gives two different values of calcium (67.1, 93.7) which I'm not familiar with, it'll be handy to check because if its 93.7 then it means you can focus your salts on upping the sodium content using sodium chloride.

The only thing you need to find out then is your sulphate and chloride which I imagine is listed somewhere or can be provided by request. You can then put those values into the Kaiser Water Calculator which would calculate for you your bicarbonate content. It does this via the Ion Balance which current stands at 50% (assuming your mean calcium is 67.1) when it would need to be reduced to 0% by increasing the level of bicarbonate. Your water is termed as hard so I imagine your bicarbonate content will be 200-300 ppm.



In terms of calculating what's officially termed as Brewhouse Efficiency you can only use an online calculator which effectively has a database of what level of extractable sugars different malts contain and then measure that against what you did extract. There's that and a whole bunch of others calculators on IBUs, alcohol content, water chemistry and their 'All Grain OG/FG' which is good for estimating your malt content in relation to your desired FG and ABV. Once you get the hang of it all you'll ultimately be able to use their Complete Recipe Builder.

http://www.brewersfriend.com/stats/

 

[HTH1975]

Thank you so much for your detailed responses - it's great to have such knowledgeable people on this forum who are willing to share their experiences. One day, I hope to be able to repay that knowledge back to the home-brew community. Cheers!

 

[Brew_Meister_General]

Thank you so much for your detailed responses - it's great to have such knowledgeable people on this forum who are willing to share their experiences. One day, I hope to be able to repay that knowledge back to the home-brew community. Cheers!

Haha! I thought the same thing when I first joined, and now I'm doing it

 

[HTH1975]

Well I look forward to the day when I'm as knowledgeable as the guys who have participated in this thread - bring it on.

I got more comprehensive report from my water company... http://www.ywonline.co.uk/web/WQZ.nsf/0/08F2F7D0B5D90B47802574FD003904A0/$file/Northallerton%202004%20WSZ.pdf

Seems my water is pretty bang on for bitters, porters and stouts.

The water hardness in my area is 93.6 mg/litre as calcium (hard). My water company also quoted the following:

CaCO3 (mg/l)233.9
CaCO3 (mmol/l 2.3
Ca (mg/l) 93.6
English (Clarke) degrees 16.4
German degrees 13.1
French degrees 23.4

Bicarbonate HCO3 for the past year was:
Max 347 mg/l
Min 28.8 mg/l
Mean 187.1 mg/l

That's quite a swing, so it's difficult to predict how the water will be when I'm brewing, without getting heavily into testing water myself.

I would mention that I'm pretty much in the same water region as Theakstons and Black Sheep Breweries - two of the largest in Yorkshire. I'd imagine they treat their water, but at least it's probably ballpark for a decent bitter or porter without treatment.

 

[Brew_Meister_General]

Well I look forward to the day when I'm as knowledgeable as the guys who have participated in this thread - bring it on.

I got more comprehensive report from my water company... http://www.ywonline.co.uk/web/WQZ.nsf/0/08F2F7D0B5D90B47802574FD003904A0/$file/Northallerton%202004%20WSZ.pdf

Seems my water is pretty bang on for bitters, porters and stouts.

So to summaries...

Calcium 67 (50 - 82)
Magnesium 16 (10 - 20)
Sodium 15 (12 - 17)
Sulphate 105 (77 - 125)
Chloride 19 ( 17 - 22)
pH 7.3 (7.1 - 8.3)

Yikes! Your sulphate is high which means it would be ideal for brewing IPAs and other bitter beers. That being said if you increase your chloride, which is very low in comparison, to 85 or 90 say (but away from 100) then that will produce a balance between sweetness and bitterness and also allow you to increase your calcium and sodium in the process using calcium chloride and sea salt.

So using the Basic Water Chemistry calculator on Brewer's Friend this is what your salt additions might look like per 10l of water:

I've also read never to use table salt as it contains iodine which sea salt and pickling salt doesn't.

And wow that is a huge swing in bicarbonate! I haven't come across that before, I'd be curious to find out why now, maybe its seasonal? But every problem has a solution! It'd probably to start a thread and get some expert feedback on your water chemistry.

 

[HTH1975]

Once again, big thanks for your input - some great advice a d I feel like I've got a better idea of what my baseline is now. Living in North Yorkshire, I had an idea that the water would naturally be good for bitters - that's what all the breweries round here are traditionally known for, and it's my favourite style of beer too. Check out Timothy Taylor beers, if you haven't already (I like Bolt-thrower best).

Regarding the bicarbonate levels, I did think that was weird. I'm going to ask my water company about that. I know that they do sample customer's water to get a sample of what domestic homes are getting at the tap, so I'm gonna ask if they would do a sample test (they can only say no). Failing that, I know that I can get a water report for around £20 by sending a tap water sample away to a lab.

 

[HTH1975]

My water company has advised me that the reason why the results are varied is because there are two water treatment works that can supply the water in my supply zone.

The bicarbonate levels for the treatment works more often supplying me are on the higher end:

Max 347 mg/l
Min 321 mg/l
Mean 333 mg/l

Ouch!!!

 

[Brew_Meister_General]

Failing that, I know that I can get a water report for around £20 by sending a tap water sample away to a lab.

I considered that too but after looking at my own report I realised that even that wouldn't give me an accurate idea just because of how much the mineral content and pH can vary. To be honest I think you have all the info you need.

I imagine the best way to proceed is to simply add the malt to the water first, give it a good stir, wait 5 or so minutes, test the pH and then adjust as necessary. Nothing ever goes smoothly anyway at first, I thought I had everything figured out before I did my first brew except reality didn't fit the theory. I didn't even test the pH and that was all pale malt, came out fine, and then when I put my stout recipe into the water calculator it told me my pH would be 2.0 when it arrived at 5.8.

My water company has advised me that the reason why the results are varied is because there are two water treatment works that can supply the water in my supply zone.

I've heard a similar thing before where you can have 2 different water supplies, one in the day and one in the night for example. I'm pretty sure I have two as well but their mineral content is very much the same anyway.

 

[HTH1975]

The 'problem' seems to be that the main water works that supplies me has higher bicarbonate levels, and the other one has very low levels - I'd imagine that this could make consistency very difficult due to the large swing.

At this stage, I'm thinking that I'm just going to brew this batch and see how it turns out without procrastinating over every last detail. I think that sticking with darker beers will put me in the ballpark for mash pH. I would however like to treat my sparge water and that is still a bit unclear to me. I did some tests with sea salt, calcium chloride dihydrate and sodium bicarbonate. The first two only dropped my pH by around 0.3, while the bicarb dropped the pH by a good 1 or more pH points. However, I'd imagine that having so my bicarb in the water could leave a weird taste.

 

[Brew_Meister_General]

The 'problem' seems to be that the main water works that supplies me has higher bicarbonate levels, and the other one has very low levels - I'd imagine that this could make consistency very difficult due to the large swing.

At this stage, I'm thinking that I'm just going to brew this batch and see how it turns out without procrastinating over every last detail. I think that sticking with darker beers will put me in the ballpark for mash pH. I would however like to treat my sparge water and that is still a bit unclear to me. I did some tests with sea salt, calcium chloride dihydrate and sodium bicarbonate. The first two only dropped my pH by around 0.3, while the bicarb dropped the pH by a good 1 or more pH points. However, I'd imagine that having so my bicarb in the water could leave a weird taste.

It'll be good to start a new thread on that and get some expert advice, I'm sure someone has had experience with it before.

Salts are used only to attain the desired water profile, its phosphoric acid which you'll need to lower the pH/bicarbonate level of your sparge and mash water, you'll be able to purchase some from a home brew store. It's better than lactic acid due to its neutral flavour.

I think sea salt is actually alkaline so better to add that during the end of the boil.

 

[HTH1975]

Nice one bud, thanks for the reply. I'll grab some phosphoric acid.

Back on the thread topic, I bought a false bottom as the pie dish rusted - should have known, seems obvious now.

I'm thinking that I'll go with a pump to circulate the wort as I've read that it eliminates the need to sparge. That would take out an extra step and (from what I gather) improve efficiency.

 

[Brew_Meister_General]

Nice one bud, thanks for the reply. I'll grab some phosphoric acid.

Back on the thread topic, I bought a false bottom as the pie dish rusted - should have known, seems obvious now.

I'm thinking that I'll go with a pump to circulate the wort as I've read that it eliminates the need to sparge. That would take out an extra step and (from what I gather) improve efficiency.

Oh you'll want sparge anyway, it's just about soaking as much of the sugars out of the grain as possible, but only until the gravity of the second runnings reaches 1.010. When it falls below you'll start to extract unwanted tannins.

This would mean taking regular samples of your second runnings using the hydrometer, with the water being drained slowly (1 litre/minute) this shouldn't be too much of a hassle. The tricky is then using Brewer's Friend's 'Hydrometer Temperature' to correct the reading as the higher temperature the higher the reading will appear, i.e. at 70c the wort will have a reading 18 higher it really is, meaning you would stop at 1.028 rather than 1.010. To be honest I do need to doubled check that.

That plus you'll only be able to fit so much water inside anyway. From all that I've read a thinner mash improves efficiency, with a 30l tun you should try and fit as much water in there as possible with each brew.

After that you'll have to take into consideration other factors like the volume of your boiler and water loss via grain absorption which is thought to be 1 - 2 litres per kg, although with a pump I imagine it will be on the lower side. An estimate of 1kg of malt = 1 litre of volume is also reasonable.

So with a 30 litre mash tun:

5kg grain = 5l volume (allowing say, 23l room for strike water)

23l / 5kg = 4.6l strike water per kg (or 1.84 qt/lb) which is great

Water loss = 5kg x est 1.5l = 7.5l

23l strike water - 7.5l loss = approx 15.5l first runnings

Sparge water: add until gravity reaches 1.010 (or rather 1.028)

 

[RM-MN]

Nice one bud, thanks for the reply. I'll grab some phosphoric acid.

Back on the thread topic, I bought a false bottom as the pie dish rusted - should have known, seems obvious now.

I'm thinking that I'll go with a pump to circulate the wort as I've read that it eliminates the need to sparge. That would take out an extra step and (from what I gather) improve efficiency.

Your wort will be high in sugars and when you drain it there will be sugars left in the grains because the wort sugars and the grain sugars will be at equilibrium and no amount of recirculation can change that. Drain out the wort and replace it with fresh water and now the grain has more sugar than the water and you can extract more sugars from the grain.

You don't have to sparge but you will gain more sugars by doing so. At the small batch size most of us do that isn't necessary as you can just add a bit more grain to get the OG you want but it does come at a cost, a cost that in commercial breweries would make them less competitive.