Infection frequency?

kurtz · Post by **kurtz** » Tuesday Dec 13, 2005 10:13 pm

Don't like to sound like a kill joy or a beer snob but if you have never had an infection how do you know what an infection is?
Most infections do not blow your head off but they are detectable at low levels though and come from many things other than improper sanitation. You might sanitise your fermentor to the cows come home but the cleanest fermentor in the world is only clean when you add the wort.
Certainly once the beer has fermented and assuming it has fermented clean, the chances of infection from most bugs are reduced due to thepH and the alcohol content. It is when it is fermenting that you have most problems.
The first is the race between the yeast and the wild yeasts that are everywhere. The suggested pitching rate fresh dry ale yeast is 1gm per litre that is 22gms per 22 litres, lager should be pitched at twice this rate.
Until the beer strain saccaromyces gets hold you have heaps of wild yeasts and bacteria who are happy to join in the party.
A slow start and or a long ferment multiplies the problems.
Actually I will start another thread devoted to this.

Kurtz

MHD · Post by **MHD** » Wednesday Dec 14, 2005 6:10 am

Hi Kurtz, I guess my fear came from all the stuff I read when I got my first kit....

Now I am about to do my first multi stage (ie I am going to rack to a secondary fermenter and leave it for a while before bottling) and I wanted to get a basic idea what the risks were....

Cheers!

kurtz · Post by **kurtz** » Wednesday Dec 14, 2005 6:53 am

Be careful of oxygen transfer when you rack, under CO2 pressure is best, as late addition of oxygen may lead to diacetyl problems but this is fortuneately easy to remedy, give it a diacetyl rest. When you finished let the temp rise up to about 20C for a day or so, the yeast will scavenge the diacetyl.

Kurtz

MHD · Post by **MHD** » Wednesday Dec 14, 2005 7:13 am

I dont have c02, I was planning using some food grade hose connected to the tap on my fermenter and letting it run through the hose to the bottom of the secondary to minimise disturbance...

kurtz · Post by **kurtz** » Wednesday Dec 14, 2005 6:53 pm

konnect the taps (keeping the mmm"Primary" above the mmm"Secondary") this will reduce the amount of O2 (and atmospheric travellers as well).
If its an ale yeast you have used watch out for diacetyl, as I mentioned before.

Kurtz