Low FG 1gal batches of wheat beer

[wildtower]

To get the hang of all grain brewing I divided a 20L all grain kit into 4 5L batches. I've been getting my OGs fairly near the mark, but my FGs have been going lower than I want for my wheat beer. I've been giving them 7 days in the primary fermenter, at 21'C/69F fermentation has been very fast to start. Is it because I've been using a half pack of yeast for just 1 gallon? Do I need to shorten the fermentation time? Also I'm bottling rather than kegging. After priming the beers have tasted ok, not too dry. But we prefer a sweeter wheat beer so I'd rather not let it get too dry.

Wheat beer Batch 2
OG 1.048 FG 1.006 - 6 days
Wheat beer Batch 3
OG 1.044 FG 1.002 - 7 days
Wheat beer Batches 4
OG 1.050 FG 1.002 - 7 days

I'm done with the small batches and brewed my first 20L batch yesterday, US 05 dry ale yeast and OG was 1.048 and I haven't seen any activity yet this morning so maybe it will ferment slower?

If you guys can guess what happened to my micro batches and maybe some suggestions on what to watch for in my first big batch, that would be really helpful.

 

[bracconiere]

what are you using on your small batches to hold temp during the mash? those are some low FGs!

 

[wildtower]

I'm working really low tech here, aside from batch 1 that mashed too high of temp, the remaining batches have been kept between 62C-68C/143-154F. I have canning pots on my gas stove that I heat to 71C/160F when I add the grain the temp drops to range and I turn off the stove, cover it, and check temp every ten or fifteen minutes. I've been mashing for 60 minutes that way. I don't have special equipment so I sparge by draining and pressing the grain bag and running an extra litre or so of hot water through the grain bag to add back to my wort.

 

[Leezer]

I wonder if your mash temps were too much on the low end of the 143 - 154F range. You could try aiming for at least 148.

 

[RM-MN]

A recipe would help a bit. I usually include a bit of caramel malt to add unfermentable sugars when I want a bit of maltiness in my beer.

 

[Zambezi Special]

I brew pretty low tech as well.
But I bring the water up to a couple dgrees centigrade above mash temp. Then add bag with grains, stir, cover pot and put the whole thing in a cooler box, lined with a duvet). The temperature stays pretty constant this way.

 

[rock_n_herm]

So, after you dough or mash in the grains, stir and cover, what is your starting mash temp? I would guess that from a 160F strike water temp, that temp drops to around 154F after mashing in. You mention checking temps each 10 or 15 minutes during the 60 minute mash - how much are temps dropping during that time?

 

[wildtower]

The temp doesn't drop that quickly, it seems to take most of the hour to fall to the low end of mashing temps. Although I should test my digital thermometer for accuracy, just to see how accurate it is.

My 20L batch also had a low FG, so I need to figure this out. SG was already 1.004 after 7 days in primary.

I buy an all grain kit that's half wheat malt and half pilsner malt. I get about 5lbs each for 20L of beer. It comes with small samples of hop pellets and a pack of US05 dry ale yeast.

 

[Zambezi Special]

Your OG seems pretty normal for the amount of grains.
I do think you need to play with your mash temperatures. It seems you are creating an incredibly fermentable wort. Maybe slightly lower mash temperatures would work?
Another thing to look at is your hydrometer and temperatures of your samples. They should be 20 oC for most hydrometers (15 for some others)

 

[bracconiere]

i just had a thought, could shoot for a strike temp to hit 160-162f....with a qt/lb ratio that let you add as much cool water to bring back down to beta range, to try and selectivly denature 'some' but not all beta amylase but keep alpha intact?