Is this temp swing why SG is a little low?

[brew_mama]

This is my 3rd brew and I am using a clone extract recipe for DFH 60 Minute IPA. I am brewing a 2.5 gallon batch. I made a 1L yeast starter with a package of Wyeast Ringwood Ale. This was my first starter as I used dry yeast in my previous brews. I have a temp controller on my fridge that I keep at 67. The OG was supposed to be 1.064 and FG was to be 1.017. I have attached the Tilt log and as you can see the starting was 1.062 and it went pretty fast at first and then over the last couple of days it has slowly dropped to 1.012. There is quite an increase in temp during the first couple of days as I know will happen and then it settles back down. It got up as high as 74/75. Was that too high and caused the yeast to go crazy and eat too much of the sugars? I haven't tasted it yet as I was going to rack to secondary for drying hopping tomorrow.

 

[Golddiggie]

Did you decant the spent starter wort before pitching the slurry into the brew? If not, there's your reason. I always chill my starters for at least a day to condense the yeast, remove as much of the spent starter wort as possible, then make a slurry of what's left and pitch/infuse that into the batch.

 

[brew_mama]

Did you decant the spent starter wort before pitching the slurry into the brew? If not, there's your reason. I always chill my starters for at least a day to condense the yeast, remove as much of the spent starter wort as possible, then make a slurry of what's left and pitch/infuse that into the batch.

I did chill the starter and I poured off a little more than half of the liquid. I was afraid of pouring off too much and not being able to get all the yeast out of the flask. Maybe I left too much.

 

[Golddiggie]

Half a liter of spent starter wort in a 2.5 gallon batch could be the reason for the lower OG. But, only being two points off is really no biggie. For the lower FG, it's not an exact process (since humans are involved).

I've had recipes that listed the FG (through software) as being one number and it came in lower. As long as I'm within the FG range it also lists, I'm OK. If it goes way lower, then something went wrong in my process (probably too low a mash temp) causing that.

Being three points lower on the FG, also really is NBD. Since you started a bit lower on the OG, you're really only one point lower. Which is probably as close as you'll ever get.

 

[brew_mama]

Yeah l figured the starter wort lowered the OG a bit, but I guess 5 pts. lower FG than what the recipe said is not too bad given like you said I was 2 pts lower on OG. I’ll see what it tastes like tomorrow.

 

[hotbeer]

Only 6 days. Why not wait another couple weeks or more?

 

[Holden Caulfield]

Was that too high and caused the yeast to go crazy and eat too much of the sugars? I haven't tasted it yet as I was going to rack to secondary for drying hopping tomorrow.

Regarding SG - I use a Tilt and find that the SG reading is fairly accurate if calibrated correctly. Whatever amount of starter liquid you added did not materially affect the SG as your Tilt read 1.062 and you were targeting 1.064.

Regarding FG - There are a lot of variables that factor into FG, most importantly are the fermentability of your wort and the yeast's attenuation capabilities, some yeast are more attenuative than others. While slightly warmer ale temperatures can speed up fermentation and lead to off flavors, it really can't enable the yeast to consume sugars that they don't have the ability to do so. As long as the temperature stays warm enough to keep the yeast from not going dormant, they will eat what they can, and most will start floccing out when there is nothing left to eat. While, your apparent attenuation is much higher than what Wyeast predicts, I would guess that the fermentability of the extract was not in line with the predicted FG. This is very common. FG is a bit of crap shoot unless you have past experience with the brew and your recipe and process are consistent.

Also, in my experience, the Tilt's FG can vary 3 to 4 points as some krausen sticks to it and alters the way it floats so you could be near your 1.017. You won't know until you check with a floating hydrometer.

BTW, 1.012 is just fine, your beer will be quite tasty, so no worries.

 

[brew_mama]

Only 6 days. Why not wait another couple weeks or more?

I’m racking to secondary then waiting a couple more weeks. Not bottling today.

 

[hotbeer]

I’m racking to secondary then waiting a couple more weeks. Not bottling today.

The only time I used a secondary, I had the worst beer I ever made.

There might have been other reasons besides just the fact I used a secondary though.

Unless you are going to be leaving it for months before kegging or bottling, I'd just leave it were it is.

 

[Golddiggie]

For a regular brew, do NOT move to a "secondary" fermenter. Instructions with that on it are ANCIENT and that part can safely be ignored. The fact that so many recipes are NOT updated with that removed, or marked as completely OPTIONAL, is disturbing.

I've had brews in fermenter for several weeks (2+ months) without any issue. Usually those are bigger beers that get something like oak added. I won't move a beer to another vessel unless it's for long term aging. As in several months (12+).

 

[brew_mama]

I've actually moved my previous brews to secondary and they turned out fine. No sediment in the bottles and they seemed pretty clear. But I might try one without to see how it is some time soon.

As for my gravity reading, after cleaning the gunk off the Tilt and putting it in the secondary carboy now it went up a point.

 

[Golddiggie]

Every time you rack a brew, you open it up to possible contamination and infection. Plus oxidization (unless you're using a completely closed transfer method, into a CO2 purged vessel).

No sediment in the bottles can be had simply by letting the yeast flocculate out in primary and proper transfer methods. TIME in primary can give you completely clear beer. With bottle conditioning/carbonating you'll always get some sediment in the bottles. Well, IF you chill them long enough that is. Even with kegging you get sediment in the bottom. The difference there is, unless you move the keg around, once you pull your first few ounces, you won't get any after that.

 

[BrewnWKopperKat]

First, welcome to HomebrewTalk!

I've actually moved my previous brews to secondary and they turned out fine. No sediment in the bottles and they seemed pretty clear. But I might try one without to see how it is some time soon.

Seems like a reasonable approach.

There's a topic, What does a secondary fermenter do?, which may be of interest. So far, It's been a reasonable, balanced, discussion about the technique.

 

[brew_mama]

Back to the topic of this thread...It is now two weeks in fermentation and my SG is now down to 1.009 for what was supposed to be an FG of 1.017. I planned to keep it in the carboy for one more week but I'm wondering now will it even be drinkable. Could I have pitched too much yeast? I did a 1L starter for a 2.5 gallon batch. Should I have just pitched the liquid packet and been done with it? I used a calculator and because it was a higher gravity beer to start with, the calculator said I needed a starter.

 

[brew_mama]

So I have cracked open the bottles of this brew and it turned out really good. No overly alcoholic taste or any off-flavors. It really does resemble the 60 minute IPA, not quite as hoppy, maybe because I can't do the continuous hopping, but instead added the hops at intervals. But all in all I'm really happy with this.

I did check the gravity with an actual hydrometer and it matched up with the Tilt. FG ended up at 1.008 so about a 1% increase in ABV, but it doesn't affect the flavor at all.

 

[CascadesBrewer]

Glad your beer turned out well.

As far as your question about over attenuation (lower gravity than expected). I am not familiar with that yeast. A 1.017 FG seems a little higher than I might expect but 1.008 seems lower than I would expect. Was this an all-grain or an extract batch?

A 1L starter for a 2.5 gallon batch might be a little overkill, but is not a problem. Did you decant the majority of the spent starter wort? I will often direct pitch a pack of White Labs or Wyeast into a moderate gravity 2.5 gallon batch.

Overpitching will not cause your final gravity to be too low. The wort starts with a set amount of sugars that the yeasts are capable of fermenting. If you under-pitch, the yeast might not be healthy enough to complete fermentation, but if you over-pitch it means the yeast will consume the available sugars a bit faster, but once they run out they run out.

Fermentation is complex and there are lots of factors involved that impact your FG. I don't put a lot of faith in predicted FG values and I don't get too worried if a batch comes in a little over or below my expected FG.

 

[brew_mama]

Glad your beer turned out well.

As far as your question about over attenuation (lower gravity than expected). I am not familiar with that yeast. A 1.017 FG seems a little higher than I might expect but 1.008 seems lower than I would expect. Was this an all-grain or an extract batch?

A 1L starter for a 2.5 gallon batch might be a little overkill, but is not a problem. Did you decant the majority of the spent starter wort? I will often direct pitch a pack of White Labs or Wyeast into a moderate gravity 2.5 gallon batch.

Overpitching will not cause your final gravity to be too low. The wort starts with a set amount of sugars that the yeasts are capable of fermenting. If you under-pitch, the yeast might not be healthy enough to complete fermentation, but if you over-pitch it means the yeast will consume the available sugars a bit faster, but once they run out they run out.

Fermentation is complex and there are lots of factors involved that impact your FG. I don't put a lot of faith in predicted FG values and I don't get too worried if a batch comes in a little over or below my expected FG.

This was an extract batch. I probably decanted a little over half of the starter wort. Since the SG was kinda high I used the starter according to a calculator, but for most of my 2.5 gallon batches, I will probably just pitch the pack and see what happens. This was my first beer using liquid yeast and the highest SG I've done.