Fermentation Fridge Temperature Advice

[Newts]

Hi guys,

I know this is a constantly repeated thread but I've been reading a lot on this and I'm still unsure what the real deal is.

I have a fermentation fridge that I'm using a STC-1000 with the temp probe attached to the side of the fermenter with a lump of blu-tack and a heat pad resting vertically against the side of the fridge. Every time I check the temperature it's within the 0.5 degrees C I've set the controller at. In my last few brews I've found that there is an off taste in each beer - it's not significant at all but I think it's noticeable. I've been brewing at 21 degrees C and they are all kit extracts to date.

In terms of sanitisation I think I'm pretty top notch. I've spent hours (if not days) watching vids on the net and reading up - currently I clean my fermenter with Pink Neo (sometimes twice) and then sterilise with Star San before I start the wort. Also have keg cleaner and sterilise with Star San before kegging.

I decided to step it up and now have an ND Brewing fresh wort kit in the fridge. One of the ones you just pour in the fresh wort, 5L of water and add the yeast. It's using a US-05 Safale yeast kit.

I just wanted to know what you would set the fridge at - I've read that typically the fermentation temperature is slightly higher than that of the actual fridge - 1 to 2 degrees or so. Is this correct? If so does that mean if I want to brew at 20 I should set the fridge to about 19? I currently have it set at 20 and I'm expecting big things from a fresh wort kit from all the other posts I've read. I've ordered another thermometer I'm planning on sterilising and putting into the wort to see what's actually happening temperature wise but delivery is taking it's time.

Please let us know if you have any input. Anything I can do to make a better brew is appreciated!

Cheers,



Newts :drinks: :drinks: :drinks:

 

[Droughtmaster]

my dad was a fridge machanic he used to say air temp mimicks water temp just a few hours afterwards , he was a old dude but his first fridges were amonia machines with out that there wouldnt be any cold are........imm smashed dont even know why i comented just thought i should

 

[citizensnips]

Ideally you want us-05 at 18, well at least that is the number majority of brewers will go for or tell you to ferment with it. I brew at 18 and get great results, I have a probe going directly into the beer so I'm not sure about your situation. Although I would say if anything brew at 18 because fermentation does create heat so at least you know you won't be well under (not that it's that bad, can handle as low as 16 I think?)..because 19-20 degrees will still produce great beers, a lot of brewers prefer to brew above 18 anyway. But I'd say get the figure of 21 out of your head and replace it with 18 as that's where you will most likely extract as little off flavours as possible and get the neutral clean crisp flavour that us-05 is known for

 

[jhay]

Do you set a differential factor in your STC 1000 .I set mine at 0.7' and find this is close to when the the fridge would normally operate if it wasn't fermenting.To do this hold the "s" button down until F1 appears.Then go to F4 to set your tolerance i.e.in my case 0.7'.

 

[QldKev]

It sounds like you have the cleaning and sanitizing working for you. Have a good look for any scratches in the fermenter, they are the perfect place for bacteria to hide. Never use a scourer on the fermenter. The other thing depending on what fermenter you are using maybe replace the tap. I'm using the bunnings fermenters and for $2 a tap any thought of infection they get replaced.

With a strange taste in there, it could be many things. Older kits and slight infection are probably the 2 main things to look at. You are trying a fresh wort kit, which are an excellent way to great beer. This should eliminate if it is a 'kit twang'.

Have a good taste of the water you are using in the beer. This makes up a huge percent of the product, so if you have a funny taste here, it will come though into the final beer.

I also have my temp probe on the side of the fermenter, so all is good there. I set the fridge temp to my desired temp, not lower.

20-21c is more where you want kit yeasts.

US-05 is 16 to 22c depending on the target style, but 18c regarded as the safe ground. 16c will produce a very clean beer, but you may have issues with the ferment stalling. The higher temps are for when you purposely want to throw some yeast byproduct flavors into the target beer, which can be great in some styles.

QldKev

 

[Nick JD]

The tap is far and away the biggest source of homebrewing infections IMO.

If you've never broken it down and smelt the sealing face between the two shafts ... you're in for a revelation.

EDIT: http://aussiehomebrewer.com/topic/10484-cleaning-fermenter-taps/

 

[Spiesy]

Ideally you want us-05 at 18, well at least that is the number majority of brewers will go for or tell you to ferment with it. I brew at 18 and get great results, I have a probe going directly into the beer so I'm not sure about your situation. Although I would say if anything brew at 18 because fermentation does create heat so at least you know you won't be well under (not that it's that bad, can handle as low as 16 I think?)..because 19-20 degrees will still produce great beers, a lot of brewers prefer to brew above 18 anyway. But I'd say get the figure of 21 out of your head and replace it with 18 as that's where you will most likely extract as little off flavours as possible and get the neutral clean crisp flavour that us-05 is known for

Yep. 18-degrees, and get a thermowell - so you can drop your probe into the fermenter and measure the actual temp of your wort. BeerBelly make and sell some nice ones that are reasonably priced (no affiliation).

If you're setting 21, and measuring the wall of the fermenter - you could be fermenting at 22-23 degrees, which probably still shouldn't account for a terrible beer, but you did say it was just noticeable... or, maybe it's just the kits?

 

[bum]

It seems to me that as many new brewers get a better handle on process they seem to complain about bad flavours showing up. This indicates one of two things to me:

• thinking about process leads to thinking more critically about the end product - maybe we start to notice more as we put more work/time into a brew?
• better process leads to the reduction of off-flavours that may have initially covered up kit twang

As Kev points out, the FWK you've got on now will be very useful in isolating your issue. Let us know how you get on.

Good luck with it.

 

[citizensnips]

I personally recon it's kit twang and most likely the best way to cover it up is with a **** load of hops and specialty malts, and ferment at 18 of course. Time will tell

 

[Nick JD]

Recently, I made a batch of 1.038 fake Kolsch with US05 ... at 30C+ due to having no electricity for 4 days and the world's worst timing.

Proves to me once and for all that fermentation temperature is not the reason kit beers have twang.

While the 30C+ beer is fruity (and only has a Saaz bittering addition), it's is far from undrinkable.

 

[Newts]

Thanks for all the replies guys. There's some interesting information here. As an update, the fermenter I'm using is near new and I've never used any scourers or sharp objects on it. The tap sanitisation is a good point. When I started brewing a few months ago I used to pull it out and sanitise this area. Haven't done that for the last few brews so this could be an issue - will do going forward.

In terms of fermentation temp the homebrew shop owner told me to brew it at 20 hence why I have it higher. I'm gonna go turn it down to 18 now. The threshold on my STC-1000 is 0.5.

I thought I'd ask these question on here as it's a more expensive brew and supposed to be a much higher quality beer. I feel I'm doing most things right with the kit beers but there are some things I'm not 100% on.

In response to your post bum, I think that at the beginning if you get drinkable beer you're happy that your new hobbies working out. I started brewing in Spring and my first two brews were fantastic. As soon as summer came I felt like giving up brewing altogether after 6 or so crappy brews but I persevered and put together my fermentation fridge and improved my sanitisation techniques. The beers brewed were literally undrinkable with ambient temps of 40-45 degrees. I also put together a 4 tap 4 keg fridge system (in my profile pic) for dispensing.

Now that I've put in all the time and effort (and money) to find out what is required to brew good beer, I expect a reasonable brew each time hence I am FAR more critical than when I began. I think I also have a better idea of off flavours to expect so the minute I taste a beer I start looking for them. If I invite friends over to check out my setup and have a drink I like to serve them a nice cold good tasting beer. I'm hoping my fresh wort kit gives pub like beer from what others have said.

The only thing that's getting me here is the "kit twang" people are referring to? Is this just an expected taste in a kit beer or is it a flavour produced by bad practice? Maybe it's time to start looking at adding some grain but I don't like to change too much at once as then I can't identify a single reason if something goes wrong :blink:

Cheers all,

Newts :kooi: