Will high SG result in high FG

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nasmeyer

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I brewed an extract Arcadia IPA clone 3 weeks ago http://homebrewing.org/assets/images/PDF/AIHrecipes/ArcadiaI.P.A..pdf using Wyeast 1028 that calls for a SG of 1054 my actual SG was 1060 partly due to not quite hitting the 5 gallon mark. Now after 3 weeks in the primary at 68-69* my gravity reading is 1018. My question is... will a higher than expected SG (was 1060 recipe calls for 1054) give me a higher than expected FG (the 1018 I have now) or should the FG still end up near the expected FG (calls for 1012-1010) even if the SG was higher than expected? I will re-check the gravity in a couple of days to see if it is still dropping, but I expected it to be done in 21 days.
 
Hi Nas:

A higher starting gravity will result in either a higher alcohol content, or a higher finishing gravity or a little of both. It depends on what percentage of your sugars are fermentable into alcohol.
Based on the recipe you posted I would expect you'll get a slightly higer gravity and a slightly higher alcohol content because the higher starting gravity was not due to an overadd of anything, but rather a shortage of water. In the future you can top off the batch after the boil with either distilled water, or pre-boiled water to bring you up to your target volume, or if you have room, and a way to measure your volume in the boil kettle you can just top off in the kettle late in the boil.
Should still be a wonderful beer though.
 
Actually you should be able to make a rough estimate of your final gravity, assuming your percentages of fermentable and non fermentable sugars increased equally and your yeast hits it's projected attenuation.
The original recipe called for an OG of 1.054, and the center of your estimated FG was 1.011, which means your projected conversion is 95.92% Assuming the sugar profiles are still in the same balance but simply more concentrated an OG of 1.060 converted at 95.92% would give you a projected FG of about 1.017. So your brew will be a bit more full bodied with just a slightly sweeter profile.
 
Zen_Brew might know the answer to this, but what are the consequences of a higher FG? Obviously it will have a lower alcohol content and maybe a bit sweeter, but anything else?
 
Actually you should be able to make a rough estimate of your final gravity, assuming your percentages of fermentable and non fermentable sugars increased equally and your yeast hits it's projected attenuation.
The original recipe called for an OG of 1.054, and the center of your estimated FG was 1.011, which means your projected conversion is 95.92% Assuming the sugar profiles are still in the same balance but simply more concentrated an OG of 1.060 converted at 95.92% would give you a projected FG of about 1.017. So your brew will be a bit more full bodied with just a slightly sweeter profile.
So if I can get a 1017 reading 2 days in a row, I should be able to rack to my secondary and dry hop?
 
Example I brewed a Sweet stout OG 1060 it would not ferment any further than FG 1018, my estimated/target FG was was 1015, there were obviously some unfermentables in there that would not allow my gravity to drop any further. ABV 5.7% it should have been slightly higher, but with a lower attenuating yeast and some unfermantables thats where it landed.

Did you use DME or LME, and what brand and color?

Briess, in particular, uses some carapils in their extracts which help with body, but they are unfermentable sugars.

Because of your more concentrated wort I would expect that you more than likely will not hit your target gravity, but keep checking it, if you have had no change over 2-3 days your done.
 
Did you use DME or LME, and what brand and color?

Briess, in particular, uses some carapils in their extracts which help with body, but they are unfermentable sugars.

Because of your more concentrated wort I would expect that you more than likely will not hit your target gravity, but keep checking it, if you have had no change over 2-3 days your done.
I used LME. Another question, if I can't get below 1018 could I consider that I have a stuck fermentation that I may be able to re-start? or just figure it is done if it doesn't go lower?
 
Zen_Brew might know the answer to this, but what are the consequences of a higher FG? Obviously it will have a lower alcohol content and maybe a bit sweeter, but anything else?

Not necessarily a lower alcohol content. Alcohol depends on amount of sugar that was converted, so if you start high, you can end up with the same or more alcohol.

Ex. Target OG 1.050 Actual OG 1.060
Target FG 1.010 Actual OG 1.014

First glance you may be tempted to say the FG 1.010 will have a higher alcohol content, but in reality the actual fermented more sugar. (46 points worth vs 40 points worth) so even though the FG is higher the actual batch will have more alcohol.

The only consequences of a higher FG in this case is a bit more body and a bit more sweetness. And in the example more alcohol.

In Nasmeyer's case if he does hit the 1.017 his alcohol will be identicle to what would have been in the original, about 5.6% ABV
1.054 - 1.011 = .043
1.060 - 1.017 = .043
 
I used LME. Another question, if I can't get below 1018 could I consider that I have a stuck fermentation that I may be able to re-start? or just figure it is done if it doesn't go lower?

No, not a stuck fermentation, just a slightly higher level of unfermentable sugars. If you get same reading 2 to 3 days in a row it is done.
 
Checked today and it is still 1018 (two out of 3 days) will check again tomorrow if it is 1018 I will rack to the secondary. Wish it had gone lower than 1018, but cant change that now.
 
Don't judge the final product until it has aged. A good IPA is supposed to have some body to it. I bet it turns out great.
 
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