Fermentation not quite there

[jimbohlia]

I made 10 gallons of the all grain Orange kolsch recipe here on hbt and had an OG of about 1.042. I fermented in 2 separate buckets using US05 yeast Harvested from a previous batch. Gravity only went down to 1.016 which gives me something like 3.25% abv. This isn't a high alcohol brew but I was hoping for a least 4% or more. It has been in primary for at least 3 weeks now and hasn't moved from 1.016.
I'm about to make 2 starters from 2 fresh US05 packets and re pitch I'm just wondering if I should maybe add a small amount of corn syrup to give the yeast something more to chew on and maybe get the abv up a little more? I've never had gravity come in low before but I've also never used yeast harvested from another batch, thinking that had something to do with it. Thanks for any advice!

 

[Yooper]

I made 10 gallons of the all grain Orange kolsch recipe here on hbt and had an OG of about 1.042. I fermented in 2 separate buckets using US05 yeast Harvested from a previous batch. Gravity only went down to 1.016 which gives me something like 3.25% abv. This isn't a high alcohol brew but I was hoping for a least 4% or more. It has been in primary for at least 3 weeks now and hasn't moved from 1.016.
I'm about to make 2 starters from 2 fresh US05 packets and re pitch I'm just wondering if I should maybe add a small amount of corn syrup to give the yeast something more to chew on and maybe get the abv up a little more? I've never had gravity come in low before but I've also never used yeast harvested from another batch, thinking that had something to do with it. Thanks for any advice!

1.016 isn't an unexpected FG for many beers, and maybe it's just done. Maybe it could have gone to 1.008-1.012 depending on ingredients and mash temp, but it's not out of line at 1.016. This one is about 3.4% from my math.

Next time, if you want a higher ABV beer, you could start with a higher OG and that would do it. The S05 already has taken care of any fermentable sugars, so repitching at this point won't help.

 

[flars]

Are you using a refractometer or a hydrometer for SG? Take a SG reading with a hydrometer, if the refractometer was used.

Was this all grain or extract? The mash temperature may have been to high, if all grain, creating less fermentable sugars resulting in the higher than normal
FG.

I wouldn't make a starter with US-05, The current SG would not warrant it. Try bringing the temperature of the beer up to 68° to 70°F for a week.

 

[jimbohlia]

It was all grain and I am using a hydrometer to take readings. I'm pretty sure my mash temps were on target. I've never heard of anyone adding a sugar later in fermentation to up the abv , would that screw it up?