Partial Mash Issues

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maggotbrain65

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Hi guys,

First post here! Unfortunately its a problem post. I have just done my first partial mash brew with the following ingredients for an American Pale Ale taken from this website.

2.2kg JWM Traditional Ale Malt
0.8 kg JWM Export Pilsner
0.5 kg Generic DME - Light
0.35 kg Corn Sugar
0.15 kg JWM Wheat Malt
0.05 kg JWM Crystal 140
19 g Pride of Ringwood (Pellets, 10.0 AA%, 60 mins)
12 g Williamette (Pellets, 4.2 AA%, 15 mins)
10 g Williamette (Pellets, 4.2 AA%, 0 mins)
1 tablet Whirfloc
Safale US 05

I used my converted 23 ltr esky with stainless steel mesh tube and ball valve for a mash tun.

I achieved a strike temp of 67 degrees with 8 ltrs mash water and mashed for 90 mins. The temp dropped to 62 after 45 mins and was returned to 67 with extra hot water.
I used another 8 ltrs for mash out then began to take the wort off the grain. I expected an O.G. a little higher but it was around 1.032. Probably lost a few litres or so due to absorbtion also.
Did a 60 min boil with the hops as above and lost more wort through evaporation , added malt and dextrose at flame out and ended up with something ridiculous like 9 ltrs into the fermenter after cooling! Topped it up to 20 ltrs and my O.G in the fermenter was 1.040 which didnt seem too bad to me. Possibly a touch low.
Then I ran into temperature problems as I chose to brew at the hottest time of the year in Melbourne! My fermenter sat at 28 degrees surrounded by frozen water bottles for 4 days furiously bubbling away and now it has finished at 1.002 and tastes bitter, but not much body.
Is it possible to add more malt extract in a secondary fermentation to boost the malt flavour profile or should I just use this as a learning experience? The bitterness is spot on but it just lacks a little body.

Any comments on my process or volume of sparge water etc would be appreciated.
Thanks
 
I tried once to salvage a brew that finished at 1002. It was an APA with 41 IBU's. I added maltodextrin and raised the FG to 1006. I wished I hadn't, it tasted worse after.

If you add malt it could work, but you might have to add too much to raise the FG to the desired level.

If you do add more malt don't go overboard, I'd just try and add enough to get the equivalent OG up to around 1040ish.

edit: Sorry I thought the OG was 1032....... Maybe notch it up to experience.
 
Hmm,

Thanks for the reply. Im thinking of just adding half a kilo of LDME into the secondary fermenter to round it off a bit. Just not sure that this is common practice. Would half a kilo make that much difference? My main concern is that the beer wont have sufficient body rather than the alcohol content it has.
Should I have used 8ltrs for mash out then added more sparge water as I drained the wort off?

Next time, I will be

1.using more sparge water
2. Not brewing when its 42 degrees outside!
3. insulating my brewing cupboard to keep the ambient temp down.

Thanks for the info though. I'll keep an eye on the post.

Cheers
 
I do about a 50/50 split of partials and AG at the moment. For my partials I've found that 1.5kg of liquid malt extract and 2-2.5kg of grain get me an OG of 1040ish and an FG of 1010ish, for a 20L batch, depending on mash temps. Even if the mash goes pear shaped you're pretty much guaranteed an FG of over 1004 from the liquid malt.
 
looking at your figures and punching them into Beersmith says that you would need to sparge more or more slowly. Anyway adding another 500 grams of lLDME will give you an equivalent OG of around 1049 400 grams 1047.
400 grams probably would not affect the bitterness too much particularly if you think the sample is bitter enough to handle it. Adding it will give you a little more body (not as watery). You would need to dissolve the LDME in a little boiling water before adding it.
The practice of adding fermentabels to the fermetenter is done in particular beer type but I have no experience with these so I will leave that info for a mor knowledgabel person than I

Cheers
Gavo.
 
I'd put it down to experience, and blend it with a fuller beer for drinking.

To end up with 20 litres in the fermenter, you'd need to use about 33L or so all up. Allow for grain absorption (3.2L), boil off (4L), mash tun dead space (3L), loss to trub in kettle (2L). Numbers will vary depending on your system but these should be reasonable for a starting point.

(I'm assuming batch sparging for this bit.) Mashing in with 8L is fine. Figuring that you'll lose the grain absorption and mash tun dead space (6.2L) on the first runnings and aiming for roughly equal sparges, mash out with about 11L to bring the grain temp up to 75-78C (work out required temp using Beersmith, Promash, whatever). Stir, let sit, then run off into kettle. Add another 14L to keep the grain bed at around 75-78C (water at 82C should do the job here), stir, let sit and run off into kettle where you should have about 26L.

That should get you to about 20L into the fermenter if my brain is still working in this heat. Also, you're pretty close to AG there with only 0.85kg not coming from grain, so why not go all the way next time? You could do three sparges if you need to in order to get it to fit in your esky.

Edit: And you'll probably lose another 1L as it cools... but the numbers above should be close enough anyway.
 
but it just lacks a little body.

you cant judge the body of a beer from the hydro tastings. Dont add anyting else, bottle it and leaveit a couple o weeks. You may be surprised.
 
Thanks for all the help guys. I really appreciate it. The recommendations on sparge amounts are very helpful so maybe I will convert to the dark side fully once Im sure that my mashing procedure is spot on.

Cheers guys!
 

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