Hi I have been buying yeast slants from brewlabs, a british company. Each one i have used has left the same sulphurous flavour in the beer. I bottled one and it got worse and worse so I thought my sanitation wasn't up to speed. So for the next one i used a pressure cooker to sterilise all wort and containers for stepping up and used yeast nutrient. I have used a 10ml , 100ml, 1 litre, starter step up.
I have one in the keg and it is good but the taste is still in the background. The one in the fermenter is really sulphery. All the different yeasts are different strains so it isn't a yeast specific thing.
Any one know what is going on?