dan125's 2018 brewdays

[foxy]

That is right about the yeast and CO2 , lots of things stress the yeast, during fermentation it is the temp, ethanol and dissolved CO2 I believe it is not the CO2 itself but the lowering of the pH level attributed to the dissolved CO2 (carbonic acid) to much pressure also suppresses the yeast esters. One of the reasons why the spunding isn't capped until towards the end of fermentation.

 

[dan125]

Funy how its always the little things - the things you never thought would be of any significance, that can lead to cock ups:

I didn't have any bubble wrap to hand when I put the FS in the fridge, to stick down over the temp probe on the side to insulate (like I have always used).
So I grabbed one of those yellow/green cleaning sponge thingies, ripped the rough green side off, and stuck the yellow sponge on thinking no more about it.
This morning the sponge has pushed itself off and the probe was dangling in the bottom of the fridge. :headbang::facepalm:

I've got the probe hastily back in position and the beer has gone up 2C overnight to 19C - so not disastrous (this time) but bloody annoying, as I like to keep it right at the bottom end of the yeast temp range until the fermentation calms down.

 

[dan125]

One of the reasons why the spunding isn't capped until towards the end of fermentation.

Do you mean it shouldn't be under any pressure until the end?

 

[Bigcol49]

I’m trying to work out how to bottle some beers either from the FS or the keg so I can share them to. Without buying a £99 beer gun

Hi!
Here's a cheap way of doing it with a carbonation cap.

 

[Bigcol49]

This morning the sponge has pushed itself off and the probe was dangling in the bottom of the fridge.

Hi!
I use a bungee cord to hold my sponge and sensor against the FV.

 

[foxy]

Do you mean it shouldn't be under any pressure until the end?

That is the idea, let all the unwanted release with the CO2, unwanted sulpher compounds etc but it does pay to play around the last one (ESB) I did I kept the pressure around 5 psi before capping at 10 psi came out real good and they seem to clear really quick, could be because a lot of the yeast drops out with the higher pressure/carbonation.

 

[Hoddy]

That is the idea, let all the unwanted release with the CO2, unwanted sulpher compounds etc but it does pay to play around the last one (ESB) I did I kept the pressure around 5 psi before capping at 10 psi came out real good and they seem to clear really quick, could be because a lot of the yeast drops out with the higher pressure/carbonation.

This is interesting as the first beer i have done with the FS under pressure the whole time @ 0.75 bar has come out a dream. No esters (CML Pale yeast x 2 packets) and is a clear as a pin and has conditioned lovely bang on to the target FG.

And the second beer has fermented out to FG within 6 days @18oC and 1 bar. I have just dry hopped it yesterday and i think i am going to keg it on the weekend.

I think the Co2 suppresses the ester production and stops the yeast getting into a chain reaction and the temp control having to control it because i am not sure if its me but beers seem to ferment out quicker in my FS.

I do agree also tho that the yeast and trub does seem to drop out more under pressure. After i had dry hopped and i flushed the FS i noticeably saw pellets being sent to the bottom of the FS.

Ah well..... only time will tell......

 

[foxy]

The first one I did I didn't have my spunding set up, did finish in five days, drinking straight out of secondary and self carbonated one week after pitching the yeast, the 2 things I noticed were the lack of esters and slightly more bitter than usual. Did read up and found that those big commercial breweries who pressure ferment lagers adjust their hop additions because of this. The first beer poured from the secondary was as bright as any beer I have brewed without any cold crash.
Though it seems like it finishes quicker, I don't know why, considering Sierra Nevada Bigfoot barley wine can ferment out at an ABV of 9.6% in 6 days in an open fermenter, I can't see a logical explanation, then again I am no microiologist/chemist/scientist, just a pleb.

 

[foxy]

Hydro-static and Gaseous pressures effects on yeast.
High hydrostatic pressure stress in the brewing industry Most yeast resist to hydrostatic pressures stress, but the brewing yeast strains cannot withstand hydrostatic pressures higher than 10MPa and gaseous pressure up to 50kPa. The simultaneous effect of high gaseous pressure and ethanol stress increase the negative effects upon brewing yeast cells. High gaseous pressure negatively affects cellular membrane integrity and cellular division cycle, which further influences the aroma of the final product, beer.
As shown the back pressure of the CO2 (gaseous pressure) is not very high at all

 

[dan125]

Hydro-static and Gaseous pressures effects on yeast.
High hydrostatic pressure stress in the brewing industry Most yeast resist to hydrostatic pressures stress, but the brewing yeast strains cannot withstand hydrostatic pressures higher than 10MPa and gaseous pressure up to 50kPa. The simultaneous effect of high gaseous pressure and ethanol stress increase the negative effects upon brewing yeast cells. High gaseous pressure negatively affects cellular membrane integrity and cellular division cycle, which further influences the aroma of the final product, beer.
As shown the back pressure of the CO2 (gaseous pressure) is not very high at all

You've lost me a bit there foxy - i don't know what those units are or how they relate to the kind of pressures we're likely to see in our fermenters.

It usually smells to me like most sulphury compounds are produced after the inital vigorous fermentation is over though.

I might try ramping up the pressure gradually next time if I get any off flavours this time round.

 

[foxy]

50 kpa is around 7 psi, I will be playing around with the pressure just to see where the pressure gets to before I start to taste a difference in the yeastiness.

 

[dan125]

Well this brew's been over 10 psi the whole time so it'll be interesting to see how it turns out.

Having disposed of the 1st bottle of trub last night my mind is turning to dry hopping - as I want to add them via the bottle on the FS to see how this works, I'm wondering if I should try to break up the pellets a bit to help them disperse.
Anyone else tried dry hopping in a FS this way?

 

[dan125]

So dry hopping via the bottle on the FS hasn't been a great success - using just 50g the pellets have broken up and swollen up in bottle, seemingly wedging themselves in.
These have been in for just over 12 hours now. Shame coz the Cashmere hops smell lovely.

 

[foxy]

Drop your pressure off and it should all lift upwards. Then set your pressure again.

 

[dan125]

Drop your pressure off and it should all lift upwards. Then set your pressure again.

Thanks Foxy, this has defo helped a bit but I think I've left it too late and most of the hops are still quite well clogged in the bottle. Trouble is as soon as I let the pressure off loads of CO2 comes out of solution - I don't want to lose all the natural carbonation if I can help it.

 

[foxy]

Might be better to dry hop earlier on in the fermentation, that way you can build up the pressure again quite easily. 20 litres will make 1.6 kg of CO2 so there is plenty to play with. Another way is to just drop the pressure and pop the hops in through the top and let the pressure rebuild.

 

[dan125]

Might be better to dry hop earlier on in the fermentation, that way you can build up the pressure again quite easily. 20 litres will make 1.6 kg of CO2 so there is plenty to play with. Another way is to just drop the pressure and pop the hops in through the top and let the pressure rebuild.

Yeah next time they're going in the top - and its tempting to chuck some more into the top of this brew, but I want to try getting a batch packaged without opening up the top at all this time round.

 

[dan125]

Kegged/bottled this brew today exactly 14 days from brew day. Finished at 1.011 - I always seem to end up with 76-77% attenuation with the CML US pale ale yeast.
Despite the nice head in the picture its a bit under carbed. There's a bit of chill haze but its coming out of the FV at 0C.
First impressions are that it's a bit under bittered for the higher than expected ABV although it doesn't taste anywhere near as strong as 5%. There is a very faint sulphury aroma.
The dry hops defo aren't coming through but the bottle at the bottom smelt amazing when I emptied it - I'll have to try these Cashmere hops again.

 

[foxy]

Have you tried the hop oils Dan, more difficult to get here but I am getting some to give them a go.

 

[dan125]

Have you tried the hop oils Dan, more difficult to get here but I am getting some to give them a go.

Yeah I've got some Citra & Cascade oil - I like them and they would be easy to add into the FS via the bottle.
I've used them a few times in conjunction with normal dry hopping, and just once instead of a normal dry hop - I thought that 7.5ml total in 25L didn't have as much aroma as the 140g dry hop I'd used in a similar recipe before.