what did I get wrong?!?

[paulyman]

Hi paulyman, would that be a finer or coarser crush though? Was thinking of ordering same grain from grain and grape to see if that makes a difference.
Other than the OG issue I can say the whole brew session went really well on the GF so with my limited experience I can recommend it.

Sorry I missed this last night.

That I am not sure of, from I've learned here, the finer the crush the better the efficiency, but with the trade off of a possible stuck sparge.I currently BIAB with no sparge and do a decent crush with a fair bit of flour and since doing that rather than having the LHBS do it for me my efficiency has increased consistently over 10%! But I'm not sure if my current crush would be too fine for the GF. Which if I do hit the purchase button I'll find out the answer to in a few weeks.


Been a heap of great posts since (and before). I'd recheck gravity first and confirm it really is way off and wasn't just the lower density runnings sitting on top when you took the measurement. I don't think this is likely after an hour boil though. The suggestion that the grain bill wasn't the correct amount hadn't even occurred to me, but is probably the most likely!

 

[pcmfisher]

I doubt if the crush is going to make that much difference. I reckon you should get better than that if you didn't crush the grain at all.

How's the accuracy of your mash thermometer? Not mashing at 40 deg or something silly?

 

[Ducatiboy stu]

Or subtract it. If it's reading 5 points higher than the actual SG and you add another 5 then your end figure will be 10 points higher than the actual SG.

Math was never my strong point in school......and then I did a trade that was full of heavy math

 

[stuartf]

Thanks for all the suggestions. Weight of grain is a possibility as I talked the guy in lhbs into giving it to me for free since I was dropping over a grand on him for the gf. Too late now to confirm that either way unfortunately. Fv is in the fridge at the moment sitting at 12C so may take another sample and let it warm to 20C and see how that goes. As fir temp controller I'm pretty sure its showing the correct temp as I was checking with a separate thermometer and both were giving the same readings at different points of the mash. Think I'll chalk it down to experience and make sure all of the above possibilities are crossed of the list for next brew day.
Cheers

 

[manticle]

I doubt any smart homebrew shop owner selling grainfathers is going to gib you a couple of kgs worth of grain.

Check a sample again as soon as you can, make sure the hydro is reading correctly as well.

 

[stuartf]

Ok remeasured at 20C and hydrometer reads 1.032, refractometer from work reads 7 brix so looks like it is a true reading. Assuming I had 5kg if grain then I've lost a load in the mash. Sparge rate seemed ok but I don't really have a previous to compare to. Guess I'll try a longer mash schedule next time and see if that makes a difference. In the mean time I've got 23l of mid strength pilsner to enjoy

 

[stuartf]

Tasted this brew this afternoon and can say its turned into a damned good drinker. Nice light sessionable beer. Will be repeating next weekend with a new batch of grain on a finer crush to increase the efficiency. First all grain brew down and id rate it a qualified success

 

[Adr_0]

The mash time could have been a touch short for conversion, as it would have been a very pale beer. Another 30min on your mash time might help in future as a first step (at least for pale beers).

You can mash out at 78°C without a drama. How long was this mashout time for? What was your sparge water temp? Sounds like volume was right which was good.

Time (longer) and temperature (slightly higher) around the mashout and sparge will both help efficiency, as they both help sugars mobilise into the runoff. The first point about a longer mash though... if all the sugars weren't there to start with you are already at a big disadvantage. If you only have 3 or 4kg of grain that won't help things either...

Great that you got a tasty beer - that should be pretty close to 100% of your goal when brewing.

You might need more mash time, hotter sparge, longer sparge like this guy said.

If you have a heap of uncracked grains, yes, a finer setting will help. If everything is cracked, endosperm broken up slightly, the gain in a finer crush than this will be in the order of a few %, not 20%.

 

[stuartf]

Yeah I'm planning on adjusting mash times a bit, especially mashout as I think it may have been a bit short. Definitely think the crush was too coarse. Looking back it was more like nearly whole grains with some cracking and a few broken up. Got the lhbs to mill a bit finer for me and the esb I just did hit the expected OG

 

[CmdrRyekr]

Mash that low you need to mash for 90 mins.

 

[Rocker1986]

Efficiency is a funny thing... I BIAB and have been achieving increased efficiency since moving to a coarser grain crush. :lol:

 

[stuartf]

Yeah I think there are a few things I need to try. Being my first ag I was pretty much doing and hoping it would be right. Learnt a lot from it though so hopefully v2 will be an improvement although that said for ny first brew I'm pretty happy with it. Big improvement in taste from the kits I started out with.

 

[marksy]

I reckon your first mash step is too short. I would aim for an hour.

Since your just starting out, keep it simple. Mash at 65 for an hour, then mash out, sparge and boil.

It`ll take a few brews to get comfortable with your new system. You can always take readings during the mash as well. You should be getting really high numbers.

I use and eksi and mash for about 2hrs to get a good eff.

You can always top up with some dry malt.

Good luck.

 

[stuartf]

Ok well brewed this again today 63C for 60, 70 for 30 mashout at 78 for 10. Had the grain milled a bit finer and hit og of 12.2 on the refractometer which is spot on for the recipe. So not the most scientific approach since I cant confirm if it was the crush or the mash that caused my original low gravity but if it tastes as good as the original beer then I'll be a happy boy cheers

 

[klangers]

Strike temperature? You mentioned mashing in at 63 oC, but did you strike at this temperature?

Doughballs?

 

[TheWiggman]

Just feedback on this, a local had his grain milled at the LHBS. I talked him through the process at his place and brought my hydrometer along. Very low SG after 30 mins mashing. I got him to recirc it and there was minimal increase. After some discussion, I challenged weighs, crush etc. and he was confident the weights were right. He got another 2 packs of premilled recipes and it was clear the crush was unacceptable.
He took them back, they agree completely, and recrushed the grain. Gravities on the next brew were completely different. For reference, original SG was 1.032 with a L:G ratio of 3l/kg. I typically get first runnings at around 1.065.

In this case I talked him into dropping his sparge and extending the boil to achieve his desired pre-boil gravity. After a long boil he was able to hit 1.062 but only half the volume. I asked him if he'd rather have a lot of weak beer or less good beer, and that question answered itself. It showed him why it's a good reason to understand the process and measure things regularly because there are many variables.

 

[stuartf]

I'm leaning towards it being my original mash protocol being too short. The second version has just finished fermentation so about to cc for a week then bottle. Still have some of the first brew to compare with but tbh I changed the hopping times so isn't a true side by side

 

[wynnum1]

If the grain is course then having the grain in water longer would allow the water to penetrate and step mash using the lower temperature would prepare for when at the conversion mash temperature is reached .

 

[danestead]

That's pretty much the standard way of testing them - in water at whatever temperature they are calibrated to, they should read 1.000. Unless one owns a refractometer as well, it's impossible to test it in a 1.040 or whatever solution and know if it's correct or not.

And if it's accurate in water, it'll be accurate in any solution. It's simply a weighted instrument for measuring liquid density, it's not gonna be accurate in one liquid and inaccurate in another, otherwise it would a completely useless piece of equipment for what it's designed for.

You can actually test the calibration at any sg quite easily with a set of accurate scales.

 

[Adr_0]

You can actually test the calibration at any sg quite easily with a set of accurate scales.

I hope you're not going to make some outlandish claim that 1° Plato is equal to 10g sucrose in 1L of water...