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Gutterbunnie

Lower than expected Final Gravity twice now

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Questioning my FGs. Still somewhat newer to using hydrometer. Why am I getting such low FGs? Is that good or not so good? last Sunday before bottling, i took a sample of Brew de Ale Ze Bub after 3 wks in fermenter. Didn't have room to cold crash but I did cool it down as much as possible in cooler to under 57F. OK so my sample reading consistently came back as 1.006, which i read several times, swirled the hydrometer. FG was supposed to be like 1.014. 1.006 just seems too much under the expected FG. No bubbles or high sediment. Sample was room temp about 64/65F. I used Safale 05 & temp controlled & fermented around 64-68F (<64 for High Krausen). But my other  batch Voodoo that You Do, the FG also came out lower than recipe indicated (and I used Mr Beer yeast with that one). Should I be concerned about my FGs? What if there's some type of bacterial or wild yeast infection that's eating up sugar in my beer & dropping FG too low? I only go 3 weeks, no more no less.

 

I sniffed my sample when it was cold, unfortunately, quite a bit of green apple notes. also tasted a little, it was very very bitter. Not gross like sewage or fecal matter.  I have hopes it's not an infection and that with enough conditioning, the bitterness with fade a bit as will the acetaldehyde. anyhoo, I read that Safale 05 can be quite estery & fruity so I'll just have to be patient & wait for final product:)

 

But just in case, I did watch the twitched video about infections & off flavors, and so I ordered a few replacement LBKs as was Josh's recommendation to replace those in 6 months because the plastic scratches.

 

Thanks for any input!

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imo us05 is the white bread of yeasts. it does the job but contributes little esters. it's a very clean fermenting yeast under temperature control.  it's so blah in character that i use a few grains when bottling after a prolonged fermentation of a high gravity beer to help tired yeast carb.  it adds nothing flavorwise.

 

final gravity 1.01 is an estimate based on an approximation of how hungry the yeast will be.  an average 'attenuation' of 75% i think is used to estimate your final gravity.  i have had many beers go down to 1.005 or 1.006  before stopping.  we're talking like 90% attenuation.  the yeast has chewed through nearly all available sugar.

 

ive never had mr beer yeast perform that well. coopers yeast did the job and the best i could get was about the expected fg of 1.015 ish.  i didnt care for the way mr beer yeast tasted if i got some bottle trub in my glass.

 

hydrometers usually have a notation on them for what temp they are calibrated for.  get a jug of PURE water.  test the gravity. it should read 1.00.  if not , then your hydrometer needs you to check the temperature it was calibrated for .. or .. just add the difference to your  readings with it.  my english isnt so good atm but i think that came out right.

 

a very bitter sample you say?  are you drawing from the spigot and getting trub in your sample? trub tastes nasty. really bitter, bready....

 

green apple usually comes from your primary fermentation (your first week of activity usually)  getting too hot inside the fermenter.  ive seen a fermentation raise the internal temp over 10 degrees from ambient.   64f ambient ->  about 74f internal... still not that hot really but close.  you shouldnt be getting that much acetyaldehyde. 

 

re scratches in lbk... really?  a guy who sells lbks suggested replacing them every 6 months?  if you dont stir inside the lbk with metal and scrape the bottom you wont get scratches. if you sanitize well before using youre fine.  i have plastic buckets with scratches. they are about 5 years old and have seen many batches. i use star san and always make sure to give it a little fresh star san in the bucket that i keep for moniths, to keep the ph nice and low. it always tests about 2.0 ph...very strong.  i partially fill the bucket. i take paper towel dip it in, swish all over the sides a couple times... wait... dump into storage bucket and boom. sanitized.  no infection .

 

 

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Yeah I don't know how accurate my hydrometer is. I've tested it with spring water but was told I must test it with distilled for accuracy & haven't done so. Where's all the distilled water gone when you really need it?

Most importantly, I need to stop watching & reading about other homebrewers' infection horror-stories. Just making me paranoid about infections. 

BTW, I just cracked open a Voodoo that You Do after almost 5 wks conditioning & it was awesome, and yes, I'm bragging. My best batch to date. And no issues & ferment temps were probably 64F ambient most of the time.

I checked my notes using the S-05 in Brew de Ale ze Bub - temps were between 61-64 ambient. I thought from what I read should have been fine even during high Krausen. I was worried about going too low & having it stall out. But I could get temps lower than that very easily, in the low 50s. Currently, I have another batch chugging along using S-05, 1776 Ale, & it started around 64 & I'm keeping it a little under that. So, we'll see. I'll have to experiment & see if I can go lower next time  without stalling & if that clears up the acetaldehyde notes. I could smell it, not taste it. Weird.

As for the sample, I've pulled samples from other batches from LBK the same way & didn't ever have this bitterness. I think it's just the style - it was Diablo HME, plus the hop boil at the end. Have to wait & see how things turn out, nothing much  I can do about it at this point - it's bottled! Now it's the waiting......not my strong suit

 

haha, scratches, well, it's possible the LBKs could get beat up quite a bit with enough use! (no I never use metal, I use silicone). No, but honestly,  I just needed an excuse to buy more LBKs while they're only $10! Doesn't hurt to have a spare or 2, or gift to another to take into the fold of homebrewing. Just wanting to share my passion, right? Right. Time to get some shut-eye.

 

Thanks for all the feedback & for the reality check - definitely need that. like others have said many times before - R, DW, HAHB! Which I did tonight & thoroughly enjoyed. Can't wait to make more beer:)

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in years of brewing ive only experienced one infected batch.  i got a lacto bacter in a wheat beer.  if you use healthy yeast and even take the slightest care for sanitation, youll be fine.

 

ales - dont let the temps go too low. 50s will likely put the yeast to sleep. lager yeast on the other hand love colder ferments.

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Good to know! I think my sanitation process is pretty good. I've been using Star San & very good about sanitizing everything that comes in contact with wort/beer. Is there ever a possibility that hop pellets could introduce an infection, even after a 10 min hop boil? Plus, I had googled "is my beer infected" & tons of posts/pics came back from various forums (too much really), and so, I'm dialing it back..........

 

Got some distilled water (finally) & test my hydrometer today just out of curiosity. Yes, it is off by .004 or .005 because instead of reading 1.00, it's at 1.004/1.005. So my FGs sound spot on after adding the difference to them. but good to know it's not uncommon to reach 1.006 FG. Read that the final product can be a bit drier with more attenuation.

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Um - am I confused?

The hydrometer  reading with distilled water  should be 1.000 but instead reads 1.005.

The error is +.005 so you would need to subtract 0.005 to get correct reading - no?

So the when FG reads  1.015 on your hydrometer it is really 1.010?

 

 

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You're right! I'm totally mixed up with the hydrometer. Yes in distilled water, hydrometer read 1.004/1.005. So I would need to subtract 0.004 from my final reading, which would bring my FG to 1.002. Does that sound normal? I'm thinking there's a flaw in my process - for this one, maybe overpitching to yeast (never used liquid before). Or, leaving it ferment too long - maybe I should have bottled at 2 weeks?  Or a wild yeast or bacterial infection?  Is it possible to over-aerate the wort? I didn't think so because I'm not using any forced air (like an air-stone), just good old plastic whisk action. hmm. Well I've gotten 3 very low readings, different LBKs, different recipes & yeast for each one. Seems odd...........any suggestions on how I can correct this? Voodoo was a good beer, no weird off flavors or over carbonation. Not sure about the other 2 yet - Brew de Ale ze Bub & the Kolsch will need to bottle condition for a time before I know if any issues. Any help is appreciate.

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I tried a Plato test but then got confused on how to correct the calibration after doing the sugar water test. Graphing? Not at 9pm on a sunday!

 

But I dissolved 3 tsp of table sugar into 3oz of pure water & my hydrometer reading was 1.052.  The reading was supposed to be 1.048. I just had to check & see if the darn thing worked at all, and it did give a different reading. Just confirms that my FGs have been very low on my last 3 batches. We're talking 1.002-1.004. Almost water, like the yeast ate almost 100% of the sugar. From what I've been reading that's not really normal or desired.

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Your FG is off due to improper temperature adjustment, see your other post.

 

I also suspect your distilled water reading is off due to the same reason or due to improper reading of the hydrometer to begin with.  

 

 

 

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Update - good news is that after 3 weeks bottle conditioning, Brew de Ale Ze Bub turned out pretty good in my opinion! I opened one last night & really enjoyed that hoppy bitterness which has tamed considerably, but still very hoppy. I used a few 12oz recycled bottles & tried one a week too soon & it had this very faint cabbagy aroma (not taste). Not sure how else to describe but it seems to not be as evident with the 22oz bottle at 3 weeks. It's likely my process. Read some potential issues could be DMS (although, with Mr Beer basic recipes, I don't think we need to do 60 min  boil, right?) I don't put the lid on my wort at any time during my process, so anyhoo. Or perhaps a tiny bit of infection? Who knows - maybe it's just my sniffer & Safale 05 with the particular hops in this recipe. But I'm enjoying my beer & will drink quickly & give some away, since we're having a heat wave & I have no where to really cellar my beer.  Waiting on a used mini-fridge which will help during summer months:)

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