Throw Out Your Cubes

Australia & New Zealand Homebrewing Forum

Help Support Australia & New Zealand Homebrewing Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Yeah, I have the containment approvals. Growing HCV, HBV, HIV Influenza all require PC2 and IBC/OGTR approval usually

Im willing to give it a go but unfortunately, I cannot measure hop concentrations.

It would be nice if someone like Dr. Smurto could also jump on board.

Could be a nice paper if it grows. A dud if it doesn't.

But hey, thats science.

tnd
 
Yeah, I have the containment approvals. Growing HCV, HBV, HIV Influenza all require PC2 and IBC/OGTR approval usually

Im willing to give it a go but unfortunately, I cannot measure hop concentrations.

It would be nice if someone like Dr. Smurto could also jump on board.

Could be a nice paper if it grows. A dud if it doesn't.

But hey, thats science.

tnd

Darren, I probably don't need to suggest it but how many "cubes" would you have. Would you have a 3 or so? So you can cover a few scenario's or would this not be needed.

And if you need some grain to be donated for the experiment, I know a supplier.....................sorry that was not called for under the circumstances but I could not help myself :p

Cheers
 
Darren, if you have the means to conduct this study there will be many, myself included, watching with interest. It would be very interesting regardless of the outcome.

Cheers.
 
Yeah, I have the containment approvals. Growing HCV, HBV, HIV Influenza all require PC2 and IBC/OGTR approval usually

Im willing to give it a go but unfortunately, I cannot measure hop concentrations.

It would be nice if someone like Dr. Smurto could also jump on board.

HPLC yeah?

It'd be nice if we could take the purified fractions and test them individually to determine the active component(s).

http://www.czhops.cz/tc/pdf/bioactive.pdf


Actually, someone here said that a patent has been awarded for something about this. If that's true, we should be able to access the patent to find the active component. You can probably just determine conc of that by HPLC.

But hey, thats science.

Yeah.. It ***** you sometimes, doesn't it? Let's hope, if this were to eventuate, that all your positive controls play ball. Consistently. :)
 
Who's the guru on experiemental design?

I'd look into pH; sugarz; hop compounds; and O2.

Otherwise you'd only learn that "wort" is/isn't capable of putting CB under its thumb. Won't tell you much.
 
Nick,

pH. sugar are easy.

I am trying to avoid the Mr. Obvious of hop concentration.

Frankly I dont give the proverbial flying fcuk as to which hop "bitters" the beer.

Not doing this myself, so if no-one comes on board then it a no-goer.

We will have to live with just collective opinion, (and my conjunctive) ;)

darren
 
OK worst case scenario, clostridium botulinum does take a hold in my cube.

Now will the cube swell up like other infections? and how long that would take?
Good question Batz - i did a bit of research a while ago - and came across a couple of things.

Firstly - it would appear that your cube will swell. How long it takes I have no idea - probably depends on the growing conditions. The amount of swelling might give an indication of just how much of the toxin has been produced...

From wiki - http://en.wikipedia.org/wiki/Botulism
Metal cans containing food in which bacteria, possibly botulinum, are growing may bulge outwards due to gas production from bacterial growth; such cans should be discarded.

This lead to another question - Would the fermentation process and subsequent alcohol production negate the botulism poisoning... and it appears the answer is no. A recent example in the news might illustrate
http://www.abc4.com/content/news/top_stori...kIkxIURU6Q.cspx

So rule of thumb - if your cube swells - discard it. Unless you want to ask yourself "Do I feel lucky?"

Well, do ya, punk?
 
If your cube swells its most likely yeast (wild or otherwise) or some other wort loving dude of the sort often found in beer, like acetobacter, lactobacillus or pediococcus, your ber is still lawn mowered, just not deadly ! Yes I know about oxygen but as TB correctly points out the standard HDPE used in food safe containers (cubes) are very porous to oxygen, if I could quicly lay my hand on Wild Brews I could tell you how much .
Like I said, cubes do not (well perhaps "have not been shown to" is a better expression) cause botullism.
K
 
Good question Batz - i did a bit of research a while ago - and came across a couple of things.

Firstly - it would appear that your cube will swell. How long it takes I have no idea - probably depends on the growing conditions. The amount of swelling might give an indication of just how much of the toxin has been produced...

From wiki - http://en.wikipedia.org/wiki/Botulism
Metal cans containing food in which bacteria, possibly botulinum, are growing may bulge outwards due to gas production from bacterial growth; such cans should be discarded.

This lead to another question - Would the fermentation process and subsequent alcohol production negate the botulism poisoning... and it appears the answer is no. A recent example in the news might illustrate
http://www.abc4.com/content/news/top_stori...kIkxIURU6Q.cspx

So rule of thumb - if your cube swells - discard it. Unless you want to ask yourself "Do I feel lucky?"

Well, do ya, punk?


Nice post unrealous,

Same goes with a mosquito bite or even a cough on a train or even no-chill.

tnd
 
Darren, I probably don't need to suggest it but how many "cubes" would you have. Would you have a 3 or so? So you can cover a few scenario's or would this not be needed.

And if you need some grain to be donated for the experiment, I know a supplier.....................sorry that was not called for under the circumstances but I could not help myself :p

Cheers

You could just pickup a few craftbrewer cubes ;)
 
I see this thread has taken a turn for the awesome. I like it.
 
Not sure if you've missed it. Germination will not happen unless there's an anaerobic environment that's sensed by the spore (the bacterium with a capsule around it). Now if the spore isn't killed by boiling, by sanitisation, by pH, by those hurdles... and that spore ends up in your oxygen-deprived, non-fermenting NC wort. Then the Go switch flicks on, and its off to infectionland we go, and toxins are produced. 500g of which can kill half the human population.
Anyway, from the discussion here, it seems that Aw and maybe Hops are the two things that might have a nullifying effect in a NC "anaerobic" environment, they're in the NC wort, and perhaps the only things that'd stop said spore going postal.

no, didn't miss it - In fact I was under the impression that I'd ben posting about just that for a few pages worth of this thread now.

You talked about the spores easily going over the hurdles to infection - but they dont. They themselves might not actually be killed by many of those hurdles, but then again, the spores themselves are completely harmless. Its only when, as you and a bunch of other people have pointed out, they germinate that they begin to metabolize, grow and produce toxins. Thats what the hurdles are about - they represent the barriers to the germination, metabolism and growth of the bacteria and they exist in the post boil wort, which may or may not contain spores that have not been killed by the previous adverse conditions. So the hurdles are in fact perfectly relevant, because at the time it matters, we are talking about bacteria, not about spores.

Most of the hurdles are however, marginal - they flirt with the edges of CB's ability to start and run, enough to inhibit it, perhaps severely, but not enough to necessarily stop it in its tracks. None of them, Low starting spore count, AW, pH, Dissolved Oxygen - individually present a sure fire barrier to the infection (with the possible exception of the hop beta acids) but they represent a series of partial barriers who's cumulative and possibly synergistic actions make it extremely unlikely that an infection could take hold. Not impossible - just extremely unlikely.
 
Darren

I can do iso alpha acid tests - its not a direct measurement of the components that inhibit CB (I believe its certain of the beta acids) but it might give you implied or comparative concentrations.

I doubt that would be good enough - but I'm happy to run the tests if it helps make the experiement fly. Mind you all I can personally offer is an iso-octane extraction through a spectrophotometer.... although if it comes to it I could perhaps spread a bit of homebrew largess amongst the lab bodies around here - someone will have a HPLC machine that I can convince them to weild in the name of the cause.

If you can tell me what we'd need to test for - I'll try to find out if we can test for it.
 
Seems to me the first thing to do is calculate the AW of wort (and if the gravity significantly alters the AW - does a double APA have a lower AW han a mild?)

I had a look at the maths and its out of my league though somebody else may be able to figure it out.

However there are 2 other ways to measure AW:

Capacitance hygrometers & Dew point hygrometers

Capacitance hygrometersCapacitance hygrometers consist of two charged plates separated by a polymer membrane dielectric. As the membrane adsorbs water, its ability to hold a charge increases and the capacitance is measured. This value is roughly proportional to the water activity as determined by a sensor-specific calibration.

Capacitance hygrometers are not affected by most volatile chemicals and can be much smaller than other alternative sensors. They do not require cleaning, but are less accurate than dew point hygrometers (+/- .015 aw). They should have regular calibration checks and can be affected by residual water in the polymer membrane (hysteresis). Dew point hygrometers

Dew point hygrometers
The temperature at which dew forms on a clean surface is directly related to the vapor pressure of the air. Dew point hygrometers work by placing a mirror over a closed sample chamber. The mirror is cooled until the dew point temperature is measured by means of an optical sensor. This temperature is then used to find the relative humidity of the chamber using psychrometric charts.

This method is theoretically the most accurate (+/- .003 aw) and often the fastest.

I don't have access to either of these but I do have a mate who owns an ananalytical food lab and he might - I'm seeing him tonight and I'll pick his brain.
 
no, didn't miss it

we're talking about the same thing. if we could sit and chat face to face for 20 seconds, we'd work that out. its a minor point that I'm making that in all the "hurdle" stages are in an aerobic environment, so no bacteria will be active anyway (atleast from Cb's perspective -- there'll be others of course where they do a fine job of killing off other bugs such as e.coli.). So, really, the only concern is spores getting through here.. and they will. Once they're in the potentially anaerobic NC environment, can they become active, make toxin and sporulate?
That's the point we're at.. as you say with Aw, dissolved oxygen, hop products. Do they present an adverse environment? I'm starting to think they do, but the reason for this (my) interest, is that nobody really has published anything solid to shows they (any of them) does [at least from the lit searches I've done].

RobW: I provided a reference earlier in this thread that suggested that yeast is inactive in a solution of Aw <0.88. So we could assume that if the wort is able to support pitched yeast growth, then its Aw is likely somewhere around 0.88. BYO's article states that Cb's limit is Aw <0.93. I don't know how different (in reality) a 0.88 solution is from a 0.93 solution.
 
Back
Top