How often are you making up for lost gravity points in AG?

[paintingken]

So, I have now done 4 all grain brews and I'm missing my gravity points. I know I can make it up with DME but wondered if I'm missing something?

I batch sparge and all of the brews have been Brewdog recipe clones (are these unrealistic targets for home brewing?)

My temperatures are spot on and my mash tun seems to hold temp very well. My grains are all pre crushed from the shop although recently I've had to buy 4 or 5 single KG bags of grain to make up the grain bill, wonder if the ratio of fine grains could be too high?

I do treat my water using the calculator and get my grain to temp. Not that it's relevant but I ferment to the correct temp in a controlled fridge. They are all IPA's

1st brew- I will discount the reading as my hydrometer was somehow faulty but final beer was definitely stronger than it should have been.
2nd brew- spot on 1,053 (Bought a new hydrometer and FV)
3rd brew- 7pts too low should have been 1,047
4th brew- 14pts too low should have been 1,072 (only just brewed yesterday but tastes fine)

Don't get me wrong, they have all gone down like free ice cream but if I've come this far I might as well get it right or should I just order some DME and admit that I'm brewing in my garage and not a brewery?

 

[An Ankoù]

I suggest you either brew short so that you get the required OG. OR increase the base malt by, say, 10% to compensate for your sparge efficiency. As your 4th, strong, brew is very short, you might look to your sparge technique as I think that's where the problem lies.

 

[fury_tea]

Are your volumes correct? Calculations correct? Wort temperature you take your measurements from correct?

I get that you want to figure out if you are making any mistakes, and correct them, but I never bother correcting with DME if I'm under. For me it's usually down to volumes, e.g. I end up with 21L in the fermenter rather than the planned 20L and that knocks my estimations off. I use a robobrew and without modifying this system it's difficult to see how much I've sparged so I just get as close as I can. Plus or minus a few points it doesn't matter, I usually end up with something I like so never see the need.

Do you take a preboil gravity reading? That could help you figure out if you are in the ball park and let you correct it with a longer or shorter boil?

 

[Hazelwood Brewery]

Unless you are using the same equipment, the same operating environment, and using all the same processes you might be expecting too much. Better perhaps to brew a beer, make adjustments to suit and then look for consistency in your own brews.

Even using a different brand of grain will give different results.

 

[paintingken]

Are your volumes correct? Calculations correct? Wort temperature you take your measurements from correct?

I get that you want to figure out if you are making any mistakes, and correct them, but I never bother correcting with DME if I'm under. For me it's usually down to volumes, e.g. I end up with 21L in the fermenter rather than the planned 20L and that knocks my estimations off. I use a robobrew and without modifying this system it's difficult to see how much I've sparged so I just get as close as I can. Plus or minus a few points it doesn't matter, I usually end up with something I like so never see the need.

Do you take a preboil gravity reading? That could help you figure out if you are in the ball park and let you correct it with a longer or shorter boil?

My volumes are spot on and I always take my readings at 19 degrees. I did wonder if say my equipment loss is twice as much as someone else by a few litres that must make some difference. I started with 39.6L for my last brew and now have 23L in the fermentor.
I will take a pre boil gravity reading next time for sure. I guess a longer boil will produce higher gravity?

 

[Rodcx500z]

Here’s a couple of screen shots of a 23L brew, the recipe and a brew day with all the amounts of water, this viable in a 30L kettle

 

[Rodcx500z]

not very clear but my total was 28.5L of water giving me 23 in the fv,

 

[Cheshire Cat]

It may help if I put down what I've done to improve my brew house efficiency BHE with the same kit.
1. Increasted my mash water to grain weight ratio to 3-3.5.
2. Added the grains gradually and stirring to avoid dough balls.
3. Reduced my mash time from 90 to 60 minutes.
4. Stir the mash after 30 minutes.
5. Changed from fly sparging to a 20 minute batch sparge at 75C.
6. Used less or equal water for sparging than mashing. I.e. 16 & 16 litres for 5kg grain bill.
7. Doing the above I've increase from 55-59% BHE to 70-74%.

Hope that helps

 

[obscure]

I typically have an efficiency of about 63%, most recipes seem to assume 75%, the thing is once you are aware of roughly what your efficiency is you can do two things try to improve it, or if you are feeling lazy like me use a little more grain to compensate, the extra cost on my 10L batches is less than a pound.

That said my efficiency used to be even worse, but a mixture of stirring to remove dough balls (seriously split one open it will be bone dry in the middle) and doing a dunk spurge (I do BIAB) have certainly helped.

 

[paintingken]

It may help if I put down what I've done to improve my brew house efficiency BHE with the same kit.
1. Increasted my mash water to grain weight ratio to 3-3.5.
2. Added the grains gradually and stirring to avoid dough balls.
3. Reduced my mash time from 90 to 60 minutes.
4. Stir the mash after 30 minutes.
5. Changed from fly sparging to a 20 minute batch sparge at 75C.
6. Used less or equal water for sparging than mashing. I.e. 16 & 16 litres for 5kg grain bill.
7. Doing the above I've increase from 55-59% BHE to 70-74%.

Hope that helps

Thanks, that does help. Does a shorter mash time help then? I guessed that a longer mash time would release more sugars.

 

[Cheshire Cat]

Thanks, that does help. Does a shorter mash time help then? I guessed that a longer mash time would release more sugars.

The opinion on this forum seems to be the mash time of 60 will give same results as a 90 minute mash, so I reduced to save time on brew day. Before joining this forum I did a 90/90 mash and boil.

 

[Cwrw666]

Do be aware that there is a lot of variability between batches of malt. It's a natural product and can't not be variable.
I found this particularly so when I was buying crushed grain. One bag would give me decent results, the next would be atrocious.
These days I only buy whole grain and crush it myself. My efficiency now hovers around 83% so to hit an OG a recipe claims I usually have to use less pale malt than stated.

 

[PerthRod]

I would try fly sparging and see if that makes any difference. (Brew Dog recommend fly sparging)

Rod

 

[Sandimas]

I typically have an efficiency of about 63%, most recipes seem to assume 75%,

+1.....this

The "problem" with AG brewing is that the recipes are only an approximation not absolutes, as there are so many variables due to everyone's different equipment, processes and grain. The biggest variable is your Efficiency, after a few brews you should start to get some consistency with this, so can dial it into your brewing app to work out how much grain you need to hit your target OG. As Obscure said, most recipes use 75% (and some use 70%) but many of us get less than this, so need a bit more grain to compensate. Obscure gets 63%, I now get a consistent 68%, so we both need to use slightly different grain bills to the recipes, to hit the OG.

 

[foxbat]

Being 7 points off on a 1.047 brew is strange. Was it a similar grain weight and water volume to the 1.053 brew that was OK?

 

[GeorgieV]

Does a shorter mash time help then?

This question was bothering me too. Then I got some iodine tincture and started doing a starch test regularly. It's different every time - sometimes it shows all conversion done before the 60 minutes mark, sometimes it needs some more time. I think there are too many variables involved, so it's difficult to do a good prediction.

 

[paintingken]

Being 7 points off on a 1.047 brew is strange. Was it a similar grain weight and water volume to the 1.053 brew that was OK?

The 1.053 (brew 2) used 36L of water for 4.75KG of grain and brew 3 used 34.2L of water for 3.94KG of grain.
Ironically I dialled it down a little as brew 2 produced 22 litres, I was not sure on the loss from the new fermenter.
Brew 3 produced 21 litres. Still needs dialling down by a litre.
Thats what made me think my mashing was the problem. After reading the advice I have put it into Beersmith software and it looks like I need to up my grain amounts to compensate. Maybe I just got lucky on brew 2.