Lager Queries

[RdeVjun]

Hi Folks,
first post & all- please be gentle!!! Great forums BTW, fantastic resources and I've spent hours trawling though many of them, just lurking until now.

Ok, so I've been doing a fair few can & kilo numbers over the last six months or so, am getting right into the swing of things and am really pleased as punch with the results (I'm guessing that 'punch' probably isn't the right term here...). So much in fact that most commercial stuff just doesn't interest me one bit any more. So, I figured I'd get a tiny bit fancy and knock up a Lager Fridge, seems they're pretty straightforward and could be the duck's nuts for the grouse. I figured with my job being largely measurement and control I'd be able to sort a simple fridge out no problems, but just in case I messed it up (plumbing or electrical), I'd do a cheapie first while I sort out the bugs and kinks.

It turns out that I nailed the hardware and software side of things first try, so I'm well pleased with that, although some would probably say I tore the fork clean out of it. Rather than just a simple, dumb off- the- shelf fridge controller, I used a (now- superseded) Campbell Scientific CR10X datalogger, one of their CS107 temperature sensors (both idle spares from work) plus a Jaycar mains relay, and it all drives dear Gran's dusty old bar fridge that I inherited a few years ago. The fridge holds a plastic carboy snugly and, as far as a Lager Fridge goes, it seems to work a treat, plus I get the added bonus of some actual data to drool over as well (yeah, pretty nuggety, I know...). Oh, I also vented the bubbler outside the fridge with some nifty stainless and handy food- grade tubing, that way I could keep an eye on progress without continually opening a cool fridge in the heat of summer, although occasional sampling for SG kind of defeats that somewhat.

So, back to the brew. I didn't want to go completely nuts with ingredients as knowing my luck, something would SNAFU and bollocks it up (after all it was _Christmas in Toowoomba_ yet again, probably not the best time of year for Lager), so I just simply used:
1.7kg Coopers International European Lager can
1.25kg Dextrose
0.25kg DME

I pitched it with the Coopers kit yeast (29007P if you want to know) at about 25deg, and it was down to about 14deg the next morning. So then, for the next three weeks, I've had the logger running it, just beautifully I might add, the typical 'deadband' control with the fridge coming on at 16 and off at 12, I'll fine that range down with the next one and lower the overall target as the average temperature during the whole time its been brewing has been about 14.6deg, maybe a bit high, but still ok I guess considering the yeast?

Oh yeah, so on to my real questions. IG was 1.043, it is now stable at 1.008, and has been there for three days now _but _ when I sample it for SG, there's i) lots of fine, small bubbles, so much so that it froths up a bit when I pop the hydrometer in the measuring tube, not out of control, Vesuvius- style, but enough for me to wonder about it should much of it end up in a bottle along with a couple of priming lollies to make it really tingle, and ii) the sulphurous smell is still fairly strong. It tastes fine, BTW, not that I've bothered with much lager before though.

So, if I had to bottle it in the next day or two as I might be going away for a few weeks, would all that gas be a drama and also, will the odour persist? I'm guessing much of the gas will be liberated at bottling, but it takes a fair while to calm down after sampling for SG and has me wondering if any of that latent gas will cause problems with MOABs ruining much of the show. I've noted with previous brews that some gas can be present, they're seldom completely flat at that stage. I'm actually hoping it will yield a persistent fine head, but we'll have to just see about that.

The odour, if it does present a problem by persisting, I can cope with I guess. Some of my marks will probably think its normal for home brew, the right peanuts...

BTW, if anyone has any ideas regarding bubbler or gas sensors that would help to keep track of fermentation, that would be fab, although its starting to sound rather industrial for what is really a hobby, but I've plenty of capacity with a CR10X (Such blasphemy! I'll never make it to brewers' heaven now...). I'm familiar with the gas bubblers for water level we use in hydrography, but that's pretty different to just measuring gas throughput. Ditto for any other water quality sensors that could be of use (we usually have EC, pH, temp, turbidity and pressure of sorts but I've not seen any gas ones before.)

Anyway, that's my lot, a thousand pardons for blethering on so. Many thanks in advance of course.

Cheers,
RdeVjun.

 

[lagers44]

Hi RdeVjun & welcome to the forum.

Don't worry about the CO2 in the beer, that's what happens when you ferment at a lower temp , the Co2 stays in suspension much the same way it does in the finished product. Some people take that into account when bottling as it adds to the overall Co2 level in the beer. There are programs out there that work this out for you just do a search on bulk priming calculators, or don't worry about it & have a slightly gassier brew.
Don't worry about the sulphur either it will go away with time, some yeasts produce more sulphur than others.

Happy brewing

Lagers

 

[matti]

As Lager says.
To add on a bit...
If you are going away for a while lower the temperature slighty an leave it fermenter.
If you bottle and then go away it is usually best to leave the bottle at optimum fermentation temperature.

If you brew at 16 degrees leave the bottle at 16 degrees.

Not to quick or the yeast will go dormant. The yeast is likely to clean up the sulphur.
If some still there when you bottle it take a while but it generally clean up in the bottle.

In the future look into a spare fermenter and the benefit of racking when brewing lagers.

 

[mattwest]

Here it is:

The NCBE Bubble counter
A battery-powered infra red counter is supplied with
two glass fermentation locks, for monitoring simple
fermentation experiments.
Bubble counter .............................................................. 46.00
Spare fermentation lock ............................................. 3.50

http://www.ncbe.reading.ac.uk/NCBE/MATERIALS/PDF/Price08.pdf

 

[seemax]

Bubbles are CO2, produced during fermentation, they tend to remain in the wort at low temps.

When bottling, the amount of priming sugar needed will be less due to this condition. Try this calculator.

http://brew.messerschmidt.com.au/index.php...p;section=sugar

Jaycar sells CO2 detectors, you could use this in the fermentor as a method for observing fermentation?

From memory the kit yeast in that kit is a hybrid and they do recommend a 14C ferment. I tried the same kit + 1kg LME with a S-189 yeast and it turned out very ordinary.

 

[RdeVjun]

Many thanks matti, Lagers and seemax- that's all logical, I appreciate and will follow your advice. I wasn't going to rack it, but I'm thinking now that the extra movement will liberate some of that gas, plus the other benefits of racking, and I'll sleep better at night. Not that I was freaking out about it, its just a niggling doubt.

Gran's bar fridge is looking like it needs company as it will only hold a carboy and a few bottles. No worries, on the logger I have another seven control channels to go, just more temperature sensors and relays needed- simple. Oh, and I already have a another fridge too, so its time to get serious. Spousie wanted rid of that fridge as it freezes stuff, so its a perfect candidate for Lagering as I'll be bypassing its own thermostat, lucky we didn't toss it.

Here it is:

The NCBE Bubble counter
A battery-powered infra red counter is supplied with
two glass fermentation locks, for monitoring simple
fermentation experiments.
Bubble counter .............................................................. 46.00
Spare fermentation lock ............................................. 3.50

http://www.ncbe.reading.ac.uk/NCBE/MATERIALS/PDF/Price08.pdf

Aww, man!!! That's precisely the thing I'm after! Fantastic, and many thanks WestOzBrew. I just knew these forums were productive territory.

They're pretty darn cheap as far as sensors go, has anyone ever used one? Am curious what the pulse voltage is, not that that will stop me, I can usually sort interfacing out.
Oh wait, I see Doc has been there already: Bubble Counter/logging [AHB Marketplace forum] . I'll suss it out some more over there.

We've mucked with optical drop counters through nozzles for waters, initially a fair PITA they were too, so the NCBE style of sensor really should've occurred to me earlier. The Omron proximity detectors we use are a bit fiddly to get the drops counting correctly, but once set they're pretty right. I'd imagine these bubble counters would be the same. I'm sold though- I wonder how long the boat from ol' blighty takes these days...

I'll look into that CO2 sensor, could be tearing the fork out of it some more, but hey, isn't that what happening already with this?

Thanks indeed everyone, I'm just stoked!
B)