Off taste after 4-6 weeks in Corni kegs

[FermentedCulture]

It's a possibility that it was the S-04 yeast that produced this flavour because it makes lactic acid. Apparently ncyc 1026 is the same as whitbread b which is s-04.

https://catalogue.ncyc.co.uk/saccharomy ... isiae-1026 (strain information: high lactic).

I gleaned this information from the yeastwhisperer on this forum, but as someone pointed out on HBT cerevisiae doesn't produce lactic acid*. Perhaps the flavour comes from another compound - the VTT entry for this yeast says it is a high acetaldehyde producer, although that is slightly contrary to this paper unless I'm misreading it. http://onlinelibrary.wiley.com/doi/10.1 ... 794.x/epdf

*edit: maybe the poster meant it doesn't produce lactic acid in appreciable amounts.

[Piscator]

While I personally wouldn't ferment in the mashtun, I would have thought that the temperatures it is heated to in the mash tun would be enough to pasteurise it (hence stuff like "raw ale")? You could probably work out how much pasteurisation occurs by inputting your mashing regime here: https://sizes.com/units/pasteurization_unit.htm

Only vegetative cells will be affected - spores will not be touched.

[Bribie]

Although not suffering from sourness (the beer, not me) I've found a big improvement in the life of my kegged beers since I started a low-to-no oxygen transfer. Basically what I do is fill a cornie keg with dilute starsan solution and serve the whole thing through a beer tap.
So I have a keg full of CO2

Then on filling, I open the lid just a crack to allow the transfer hose right down to the bottom, and fill the keg. As the beer level rises it expels the CO2 along with most, or all, of any air that's trying to work its way in from the open lid.

Then I seal and thoroughly flush the headspace with CO2.

One real benefit is that as the initial rush of beer splashes and foams in the cornie it's doing so in a pure CO2 atmosphere and I guess that's the main point at which beer gets oxygenated in a cornie. The gas isn't expensive over the course of a cylinder (10kg in my case) and the improvement in freshness and stability is amazing.

[orlando]

Although not suffering from sourness (the beer, not me) I've found a big improvement in the life of my kegged beers since I started a low-to-no oxygen transfer. Basically what I do is fill a cornie keg with dilute starsan solution and serve the whole thing through a beer tap.
So I have a keg full of CO2

Then on filling, I open the lid just a crack to allow the transfer hose right down to the bottom, and fill the keg. As the beer level rises it expels the CO2 along with most, or all, of any air that's trying to work its way in from the open lid.

Then I seal and thoroughly flush the headspace with CO2.

One real benefit is that as the initial rush of beer splashes and foams in the cornie it's doing so in a pure CO2 atmosphere and I guess that's the main point at which beer gets oxygenated in a cornie. The gas isn't expensive over the course of a cylinder (10kg in my case) and the improvement in freshness and stability is amazing.

I take a similar approach and am achieving similar results. It doesn't stop the beer going through the usual maturation pattern but it certainly seems to slow down staling.