Airborne nasties - just a thought!

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evanvine

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We can eliminate nearly all “nasties colonies” in our vessels, tuns and containers by dedicated sterilisation.
I do hate the Americanism “sanitation” as it makes me think of cleaning loos etc!
The problem (as I see it) is airborne nasties.
With these we are between a rock and a hard place in as much that we have to aerate our worts and starters to generate yeast growth.
I think we can prevent a lot of these by using an aquarium type compressor and filtering the air through cotton wool or other medium.
Any thoughts on this matter would be greatly appreciated.
Pic shows airborne nasty contamination on my discarded grain and hops after only a few days.
P1020088a300x275.jpg
 
evanvine said:
We can eliminate nearly all “nasties colonies” in our vessels, tuns and containers by dedicated sterilisation. I do hate the Americanism “sanitation” as it makes me think of cleaning loos etc!
I do hate the misuse of the term sterilisation . . . when something is sterile (in this context) it has NO contamination . . . all bugs and spores are killed . . . what we achieve using chlorinated caustics, iodophors, Quats, boiling water etc is a long way off that . . . The level of the bugs is reduced incredibly though and that is good enough . . . . but it isn't sterile, which is what I aim to achieve when I am yeast culturing . . .Autoclaving everything at 120C for 15 minutes or flaming to read heat, achieves exactly that . . . can't do that with plastic though.

having reduced the bugs to a very low level, we pitch a massive amount of yeast which out competes the bugs and turning the wort into beer . . . increasing the conditions away from the ideal for bug growth, so they tend not to grow. . . . Plus we take steps to keep our wort away from further contaminaition . . .unlike the ex contents of your mash tun.
 
AM
Thank you for your in depth reply; I take the point, but I still shudder at the word “sanitise”!
Strikes me that “Domestos” are telling porkies when they claim, “Kills all known germs dead”
The picture was just a bit of drama and not meant seriously.

Kind regards
 
evanvine said:
Strikes me that “Domestos” are telling porkies when they claim, “Kills all known germs dead”
:ugeek: Actually its 99.9% . . . which is what we want. The effectiveness of 'disinfecting agents' is generally described as the length o time required to reduce the live bug count by 1000 times (~99.9%). . . . Unfortunately the FDA 'standard' test states a minimum contact time of 20 minutes . . . even when the agent has completed it's disinfection within the first 30 seconds or even instantaneously (Like Peracetic in a fogging application) so everything we get states a contact time of 20 minutes.

Actually I don't like the term sanitise anyway as it sound to much like taking the rubbish out to the bin . . . Sterilise is too strong a word . . . and I'm not really comfortable with disinfect either :hmm:
 
Aleman said:
evanvine said:
We can eliminate nearly all “nasties colonies” in our vessels, tuns and containers by dedicated sterilisation. I do hate the Americanism “sanitation” as it makes me think of cleaning loos etc!
I do hate the misuse of the term sterilisation . . . when something is sterile (in this context) it has NO contamination . . . all bugs and spores are killed . . . what we achieve using chlorinated caustics, iodophors, Quats, boiling water etc is a long way off that . . . The level of the bugs is reduced incredibly though and that is good enough . . . . but it isn't sterile, which is what I aim to achieve when I am yeast culturing . . .Autoclaving everything at 120C for 15 minutes or flaming to read heat, achieves exactly that . . . can't do that with plastic though.

having reduced the bugs to a very low level, we pitch a massive amount of yeast which out competes the bugs and turning the wort into beer . . . increasing the conditions away from the ideal for bug growth, so they tend not to grow. . . . Plus we take steps to keep our wort away from further contaminaition . . .unlike the ex contents of your mash tun.


No they don't. 99% of brewers here massively underpitch a yeast that hasn't even started to work. You want to pitch yeast that is like a scary movie and trying to consume evrything in it's path. If your brewing 40L you want to pitch 1L of fiesty, fight everyone, eat ya kids, take you all on yeast. Then you WILL NOT GET AN INFECTION. The amount of C02 that bugger will produce in 48hrs is enough to kill anything. 72hrs later your brew should be finished. Not 10 days later. Using the right amount of yeast you should have fermented out the sugars in 2-3 days. You think millions of hectolitres at Becks have 10 days to ferment?
The single biggest failure for home brewers is underpitching yeast.
 
Aleman said:
evanvine said:
Strikes me that “Domestos” are telling porkies when they claim, “Kills all known germs dead”
:ugeek: Actually its 99.9% . . . which is what we want. The effectiveness of 'disinfecting agents' is generally described as the length o time required to reduce the live bug count by 1000 times (~99.9%). . . . Unfortunately the FDA 'standard' test states a minimum contact time of 20 minutes . . . even when the agent has completed it's disinfection within the first 30 seconds or even instantaneously (Like Peracetic in a fogging application) so everything we get states a contact time of 20 minutes.

Actually I don't like the term sanitise anyway as it sound to much like taking the rubbish out to the bin . . . Sterilise is too strong a word . . . and I'm not really comfortable with disinfect either :hmm:


70% methylated spirits-kills all that can infect a brew, is cheap and even gives viruses a hard time. Sure beats 'sterilising' everything to death-only for it to become 'infected' as soon as you touch it. :thumb:
 
evanvine said:
I do like the idea of a violent, homicidal yeast!!

Why would you want to pitch a 'flower arranging yeast' when what your after is an axe wielding maniac of a yeast?
 
When I was studying at university I did a course in microbiology.
This involved growing yeasts, fungi and bacteria on agar plates.

The lecturer said the chance of infection from airborne contaminates was so small to be insignificant. Our control plates proved this (in the lab anyway).
In fact one week in ideal conditions would only yield a few small colonies from a finger print, piece of hair, or grain of soil.
I think people worry too much.

A good disinfection, sanitation, sterilisation (whatever) regime is good practice.
 
True.
But how many years had he been working in a lab before that chance infection?
It's also not clear if that infection was airborne.

I still maintain that an airborne infection is unlikely.
 
Aleman said:
evanvine said:
We can eliminate nearly all “nasties colonies” in our vessels, tuns and containers by dedicated sterilisation. I do hate the Americanism “sanitation” as it makes me think of cleaning loos etc!
I do hate the misuse of the term sterilisation . . . when something is sterile (in this context) it has NO contamination . . . all bugs and spores are killed . . . what we achieve using chlorinated caustics, iodophors, Quats, boiling water etc is a long way off that . . . The level of the bugs is reduced incredibly though and that is good enough . . . . but it isn't sterile, which is what I aim to achieve when I am yeast culturing . . .Autoclaving everything at 120C for 15 minutes or flaming to read heat, achieves exactly that . . . can't do that with plastic though.

EXACTLY! No home brewer has ever achieved sterility. Even if you do so with bleach etc..

As soon as your kit is exposed to air.. contaminated
As soon as you rinse with tap water... contaminated

Not sterile!

Sanitation is actually a good word because it conveys the idea that the contamination has been reduced to an acceptable level. Sterilisation is misleading.
 
evanvine said:
I think we can prevent a lot of these by using an aquarium type compressor and filtering the air through cotton wool or other medium.

You need to be careful that your filters arent just acting as breeding grounds for nasties and end up amplifying contamination... filtering through cotton wool is no good. You will just suck the bugs out of the cotton wool and into your brew.
 
Varnish said:
When I was studying at university I did a course in microbiology.
This involved growing yeasts, fungi and bacteria on agar plates.

The lecturer said the chance of infection from airborne contaminates was so small to be insignificant. Our control plates proved this (in the lab anyway).
In fact one week in ideal conditions would only yield a few small colonies from a finger print, piece of hair, or grain of soil.
I think people worry too much.

A good disinfection, sanitation, sterilisation (whatever) regime is good practice.

I did a Msc in microbiology and plant biotechnology with a few years experience growing theraputic t-cells for leukemia patients at UCL/UCH.....

Your lecturer is only correct in the context of culturing very fast growing bugs like E.Coli overnight. In the context of culturing something like human cells which take two weeks, or plant tissue which takes six weeks to several months (similar time to beer in fact), airborne contamination is a very significant factor indeed.

In order to achieve <50% contamination of plant tissue culture the precautions neccesary were extraordinary and far beyond what could be achieved at home.... even then one small slip and 6 months of work is crawling with fungus.....

Truth is we get away with it because the hops, alcohol, and anearobic environment make it hard for most uglies to get a toe-hold in the beer.
 
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