Final Gravity and ABV on my first two batches

[flushdrew42]

Hey all,
I've got two batches brewed, and both seem a little short on ABV...

batch #1 was the MrB WCPA 2 weeks in fermenter, and ended up w/ a FG of 1.013 and an ABV of 3.7

Batch #2 is this recipe, and ended with FG 1.014 for about 3.99ABV.
(1.5gal batch)
1.5lb NB Dark LME
1/4lb of Molasses
60 min boil, hops 60/15/5
Muntons Ale Yeast - @80F - fermented primary 10days, now racked to secondary both @ 65F

I just brewed this recipe saturday and am wondering how it will turn out. i didn't have my hydrometer til monday, so i'm slightly blind on OG.
(again 1.5gal batch)
1.5lb NB Gold LME
0.5lb Dark Brown Sugar
60 min boil hops 60/5
muntons ale yeast @75F - fermentation temp of 65F.

any thoughts on low abv? or am i just not having enough fermentables to raise it? i was using the idea that 1lb of fermentables per gal = 5%abv... (something i'd read here)
thanks!

 

[david_42]

It's more complicated than that because LME, DME, grains and sugars all have different levels of fermentables. LME will yield about 4% ABV per lb per gallon.

 

[ReverseApacheMaster]

That recipe #2 should have yielded closer to 5% ABV. How did you take the OG reading? Was this a partial boil? Did you adjust your hydrometer readings based upon temperature?

 

[flushdrew42]

i'm slightly n00btastic and may have missed my adjustments a bit but FG was taken at 64F and adjusted from there based upon a reading of 64F water,

but the OG readings were not taken due to not having a hydrometer
(until yesterday - thank you not so L-LHBS)

 

[ReverseApacheMaster]

FG readings aren't accurate based on that estimated abv scale. You need the OG readings to compare.

 

[flushdrew42]

I figure i'll update this thread, as to not spam with another thread.

i took a gravity reading from the Golden Ale I brewed last saturday.
i ran the recipe through QBrew and it estimated the OG to be 1.051 - Qbrew FG was estimated to be 1.013.

the actual FG from today was 1.010.
which puts the estimate of 5.0ABV, short of the actual ABV of 5.5%.

the porter (first recipe in OP) i was originally worried about, i took a sample today, and it was 1.012. which based upon that, brings actual ABV to 4.3%. so i bottled it today.


lesson learned? yeasts are amazing. knowing the actual FG is 10000% more valuable than any estimate. also, more time = more yeast work. patience is a virtue, and one i'm very happy i employed this time.

i didn't brew today, it's my 8y/o's birthday and so i'm going to wait until tomorrow to brew batch #4. The pipeline is up and going.