Chilling cube in river stream

[jbaker9]

Hi,

I use a cube solely to allow me to do 2 brews on one day (2nd brew goes into cube to transfer to fermenter after 1st batch finishes).

I have access to a cold river stream and was thinking of using it to cool the cube to prevent excess bittering and ensure my flavour hops survive.

How long should I wait before chilling the cube to ensure everything is well sanitised and low risk of infection in ~3 weeks in storage?

 

[malt junkie]

Pasturisation @ 80c is around 8 minutes (correct me if I'm wrong here MHB, etc) I'd let sit for 12 min and dunk it, just remember to spay it down with some sort of sanitiser your before going to open.

 

[manticle]

Way less
72 for about 15 secs for milk,90 for about 1 second.

 

[malt junkie]

sorry, manticle your right, I was quoting pasturising a bottle insitue. Quite obviously the wort is already at temp.

 

[Mikeyr]

Damn we want pictures!

Theres a mad photo from those crazy victorians with a bloody ...... whats the plural of cubes..... a yahtzee?? ......... rubix? ...... pod of cubes floating around a pool.

Been doing it myself ....... but a stream ..... lets call it a river! Awesome!

 

[Florian]

Just make sure you tie it to something so it doesn't swim away...

Also, I would really avoid getting the opening under water even when the cube is properly closed. Which in turn might give you a headache balancing the bloody thing in the river.
Remember it won't sit in there like a rock would, it'll be all floatyboaty.

 

[Lyrebird_Cycles]

None of the above.

Pasteurisation level in PU per minute is given by 1.398(T-60) where T is the temperature in oC, normally 25 PU is considered adequate for beer (but not for wort, see below). BTW 1.398 is simply log10 of 25, so this is equivalent to saying that PU = 10(T-60) / 25.

Technically, the above is a gloss for standard conditions. To make an accurate prediction for non standard conditions you need to know the D value (death rate) and Z value (rate of change of D value with temperature) for the target organisms in the medium. Both D values and Z values change with pH which is why wort requires more PUs than beer because the pH is higher. I think** the D value for Lactobacillus in milk is slightly lower than that for Saccharomyces in beer, hence the shorter times in Manticle's post above.

OP: there is no answer to your question. There are potential spoilage organisms present in the wort which survive* a 90 minute boil and would be likely to survive whatever you threw at them in the cube short of autoclaving it.

Normally they are of no consequence because the wort is taken to fermentation quickly and they are out competed by the yeast. I do not know what happens to them in three weeks. I suspect you are about to find out.

* in spore form.

** never worked in dairy processing, would have to look this up and couldn't be arsed.

 

[manticle]

Those spores that can potentially form just don't seem to ever cause any issues in a very large number of properly made and stored no chill worts.
One instance where I'll definitely trust anecdotal and experiential over theoretical. That said, I'd love to see some hard data from a well run study on survival rates of harmful microflora in no chill worts.

And yes milk is different to wort but as you point out - if it survives 90 minutes of boiling, it will survive 1 min, 5 mins, 8 mins or more at 80 so if you're already taking a punt with no chill (which I regularly do) a few minutes to get the cube surface to 70-80 should be ample for our purposes.

 

[Lyrebird_Cycles]

Agreed: theory is a generalisation from accumulated experience.

I don't do "no chill" so I wasn't going to venture a specific answer to the OP's question but if pushed I'd opine that around 15 minutes would be the point of diminishing returns. Dunk it in the stream and keep it cool, if it doesn't swell use it.

 

[jbaker9]

Great discussion. I'll put some photos up in the weekend!

 

[Coldspace]

I usually fill my cubes after shut down, wirlpool temp on gf drops to about 92. Fill 2 clean and starsan spayed cubes as I double batch. Wait 3-4 mins, with cubes on side to sanitise lid/handle then drop them into my swimming pool for an hr or so while I clean up.
Have had no problems with swollen cubes, have had some sit in my shed for 3 months no issues, and turned out excellent beers.

Go for it.

 

[Lyrebird_Cycles]

Those spores that can potentially form just don't seem to ever cause any issues in a very large number of properly made and stored no chill worts.

Thinking about it some more, I think the difference is one of perspective. The info I posted pertains to commercial heat treatment regimes which are predicated on achieving a better than one in a million failure rate. That might sound ludicrous until you realise that's more than two failures a day when you are running a 1500 can a minute filler.

Unless there are lots more home brewers no chilling than I think there are, we're in a different ball park here.

 

[Ducatiboy stu]

Depends on how well santised your cub is to begin with as well

But in general it should last a fair while in the sealed cube.if you have done everything right

Basically, if it doesnt swell after a few weeks, looks like a duck, tastes like a duck then you will most likely have a duck

 

[mofox1]

Oh great... so it wasn't enough to have kittens in airlocks, we now have ducks in cubes?

 

[manticle]

Thinking about it some more, I think the difference is one of perspective. The info I posted pertains to commercial heat treatment regimes which are predicated on achieving a better than one in a million failure rate. That might sound ludicrous until you realise that's more than two failures a day when you are running a 1500 can a minute filler.

Unless there are lots more home brewers no chilling than I think there are, we're in a different ball park here.

There are definitely a lot of no chillers and they are definitely producing a lot of wort on multiple occasions. However there is still every likelihood that we are coming at it from different perspectives. Apart from fwk (and I believe the process likely differs from HBNC), NC is really on suitable for home brewers or very, very micro at the outside.

 

[TheWiggman]

I don't do "no chill" so I wasn't going to venture a specific answer to the OP's question...

Buy yourself a container and join the movement, and just like using airlocks you won't look back.

 

[Lyrebird_Cycles]

I have tried it, I don't like it. I preferred the version with the block of ice to pull down under 80 straight away to the total no chill, but I prefer wort chilling to both.

Horses for courses etc etc.

 

[technobabble66]

...I have access to a cold river stream and was thinking of using it to cool the cube to prevent excess bittering and ensure my flavour hops survive....

Hey, fwiw, you shouldn't need to worry about the issue of the heat damaging the "flavour" impact of your hops in the cube.

The bulk of the flavour impact of the hops in the boil decreases over time because the volatile oils (as opposed to the bittering alpha & beta acids) are boiled off and lost in an open kettle/urn.
Whereas in the cube, these oils are captured and held inside the cube, so should be more reliably incorporated into the wort. The lower temperature may compromise the chemistry to fully incorporate and transform these oils/compounds, but at least they're not being lost quickly.

Note there's big differences in the consequences of this between hops added (very) late in the boil to those hops added into the cube, given the short exposure of the late hops to boiling temps - both in terms of oils losses and specific chemistry kinetics fuelled by the higher temps.

So in that sense, the "flavouring oils" from cube hopping (or maybe very late hops additions), should actually be incorporated better than a typical 15-30mins (boiled) addition.
I'd stress there would be differences in chemistry with downstream byproducts/compounds due to the temperatures being well below 100°C, however, the fact the oils are not lost should offer the hope that the flavour impact is potentially being maximised.

2c

EDIT: so (again, fwiw) i prefer to leave my cubes to slowly cool on their own and then compensate/calculate the effect this has on bitterness, rather than try to speed their cooling. This is to maximise the chemistry that is theoretically occurring/required to incorporate the oils into the wort.
(i.e.: you want the oils to actually bond into compounds in the wort, rather than simply be dissolved into it and remain separate molecules; otherwise the CO2 from fermentation will simply "scrub" out these oils later on. Plus many of the flavour compounds we detect in the finished beer are actually modified version of these oils, not just the simple oils themselves. Does that make sense? :huh: )

 

[Lyrebird_Cycles]

i prefer to leave my cubes to slowly cool on their own and then compensate/calculate the effect this has on bitterness, rather than try to speed their cooling. This is to maximise the chemistry that is theoretically occurring/required to incorporate the oils into the wort.
(i.e.: you want the oils to actually bond into compounds in the wort, rather than simply be dissolved into it and remain separate molecules; otherwise the CO2 from fermentation will simply "scrub" out these oils later on. Plus many of the flavour compounds we detect in the finished beer are actually modified version of these oils, not just the simple oils themselves. Does that make sense? :huh: )

Although the chemistry of hop flavour is very complex and many things are not understood, I do not believe that hop oil borne flavours bind to anything in the wort. I've seen it stated many times but I do not know of any evidence for it and I think it arises from two sources of confusion:

Firstly from confusing hop oils with hop polyphenols, which do indeed bind to wort (and other) proteins. This is an entirely different process.

Secondly, many plant derived flavours exist initially as glycoside precursors which are then split to form the flavour (called the aglycone) and a sugar molecule. This happens during processing and during fermentation, I don't know if it happens during the boil but I suspect it does. Again glycosides are not oils although the aglycone can be moderately hydrophobic and the glycoside will be water soluble because the sugar moeity makes the glycoside as a whole sufficiently polar.

As stated, the above is based on not knowing of any evidence of hop oils binding to wort. If anybody does know of any such evidence I'm all ears.

 

[Ducatiboy stu]

Oh great... so it wasn't enough to have kittens in airlocks, we now have ducks in cubes?

You better believe it

https://www.youtube.com/watch?v=0vu_uxsngS0