Propagating Liquid Yeast

[scotty1975]

Hi all,

Firstly,Sorry about the long post.

Recently I have propagated 3 different liquid yeasts as per instructions i found on this site. I used a glass carboy with an airlock each time.

The first was white labs 830 and it worked fine.
The last two were 800 pilsner and 002 british ale. I left them in the carboys for nearly 2 months as i have been a bit busy. When i divided them up into sterilised containers i tasted a bit of the wort and it has a slight sour taste. I am worried that they are infected, but i dont see how as they were never opened and i am pretty anal about sterilisation.

I have used the 830 once and the beer seems fine, so today I opened one of the remaining containers of 830 i have in the fridge and tasted some of the wort on top of the yeast and that has a slight sour taste as well.

Do you guys think my yeast startet=rs are stuffed or is it usual for the wort to taste slightly sour. Also, the temps may have gotten close to 28-30 degrees if this makes a difference.

Any advice would be greatly appreciated

Scotty

 

[Gough]

G'day Scotty,

It is pretty hard to say for sure without tasting the starters and knowing exactly how you made them etc, but in my opinion if it is tasting sour I wouldn't use it personally. Depending on your definition of sour, it sounds like an infection to me. Hope I'm wrong though and that they are fine Personally though, like I said, a sour yeast starter wouldn't be getting near my beer...

Shawn.