does long fermentation imply anything bad?

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I'm currently brewing my 2nd beer kit, a Woodforde's Bure Gold. The instructions say 7-10 days fermentation, but its been 15 days now and it is still slowly bubbling away. I also have an ispindel in there:
buregold gravity.JPG


I suspect the numbers themselves are out, because I didn't calibrate it myself (it was sold as calibrated, but perhaps that was an exaggeration), but the trend is still down, which I understand to mean (combined with continued bubbling) that fermentation continues.

Is this indicative of a problem?

If not, what do you far more experienced brewers suggest I do if this is still going on by Sunday when I'm due to go on holiday for 2 weeks? ie leave it, keg it anyway, something else? Its in a brew fridge fwiw so I have complete control over the temperature.
 
No, it doesn't necessarily indicate a problem. Some yeasts are just like that, and sometimes it just takes longer (I've had this recently and no idea why - I didn't have fermentation tracker and ended up bottling it too early and it hugely over-carbed). Which yeast was it?
 
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There is a chance that the continued drop in gravity is a result of an infection, but the simplest explanation is that it's just still going.

The best way to tell if there is a problem is to taste it. If it tastes bad, you have a problem. If it doesn't, then there is no problem.

If it is infected, there is nothing you can do about it so you may as well leave it to finish fermenting, then see what it tastes like when you bottle it.

Normally, I wouldn't expect the SG to be that low, but given you didn't calibrate the iSpindel then your right to just look at the general trend and ignore the actual values. I recently bought an iSpindel and when I put it in plain water at 20°, it read 0.984 instead of 1.000. I've since calibrated it!
 
All the brews I've done with my Brewbrain floating hydrometer start out being bang on gravity, correlating with the hydrometer, but have ended up 'apparently' below 1.000 because the float always seems to end up with a big dollop of krausen on top of it - when double-checked, the brews have all been on target between 1.008 and 1.011. I haven't even bothered using it on my most recent brew.

It's great for confirming fermentation has kicked off, but otherwise just a toy really. Pouring some wort/beer into a sample jar and testing with a hydrometer is the only real way to be sure.
 
I used to find kits, especially the 2 can ones, a bit slow to finish fermenting. I had one that took 5 weeks which is ridiculous.
 
OK, just took a sample and it doesn't taste foul. It could be strong, but I might just be imagining it. I measured it with my traditional floating hydrometer, which although isn't very precise suggests that the ispindel isn't far off; I read it at about 1.004, but it is difficult to read.

I think I need to buy a more specific hydrometer, mine is for wine or beer which makes the scale too small
 
It looks to me as if it is all about done as the graph shows it pretty stable for the last 2 days, give it another day and if it stays virtually the same get ready to bottle or keg.
I would ignore any slow bubbling as it may be the yeast cleaning up and CO2 being released in the process.
You do need to record the true FG with a reliable hydrometer one of the £4 ones from Wilko's are generally good enough for most homebrewers.
Good Luck
 
I would ignore any slow bubbling as it may be the yeast cleaning up and CO2 being released in the process.
Interesting. Thanks.

You do need to record the true FG with a reliable hydrometer
For my own information, why?

I (mis?) understood the point of measuring the FG was to either calculate the ABV (if you have the OG) and/or to know when the fermentation had finished based on a recipie/kit's known target FG. The instructions on this kit just specify 'below 1014' which I think I acheived quite some time ago.
 
Yes the FG is there so that you can calculate the ABV, to help with indication of when it has finished fermenting and also so that you can use the recipe and fermentation as a record of your brewing. You can also use it so that you know what different yeasts will do with the same beer, lets say you wanted it to finish at say 1.008 and not just around the 1.014 Fg as you may prefer that beer drier than than it finished this time.
The more info you have regarding a brew will help in your mission to become a better brewer.
I was under the impression that graph was from a Ispindel which are not always the most accurate piece of equipment for giving correct gravity readings and your graph is showing way lower than would normally be expected to be that low as AgentGonzo said which indicates that is not the true/accurate gravity
 
So in short, you only need to accurately record the FG (and OG) if you want to know the ABV. I went through a couple of years of slapdash brewing where I was just making ~4-5% beers, and the actual ABV didn't matter, so I didn't measure it (some brews I didn't even weigh the grain, I just eyeballed it knowing 'most' of a scoop from one of my jugs was ~500g). I make better beer now that I measure thing and record my results, but more importantly I adapt my future brews based on my notes to improve future brews, rather than blindly guessing 😂.
 
I've ordered a hydrometer which should be easier to read for the next brew.

I kegged today, and this is what the beer looked like on top when I opened it.
IMG_20220805_185119.jpg


Looks good to me, and it smelled OK. Fingers' crossed.
 
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