This is a small "how to" I wrote to explain to the guys at beer club how to get their hands on free brewery yeast. You'll need the following items. Bottle Conditioned beer - make sure you get one where they use the primary yeast strain in the bottles, I have had good results with Brakspear, Fullers and Hopback yeasts. A sterilised demijohn, funnel and airlock A 1.020 malt solution A pan for boiling 2l of liquid in Start by boiling up the malt solution, you can use unfermented wort from a previous brew and the following formulae to dilute it to 1.020 (Volume*Gravity points)/Desired Gravity = Volume of water to dilute with Or you can just add 200g of dried malt to 2 litres of water, either way boil it for 10 minutes to ensure it is sterile. Once it's cooled a bit pour it into your sterilised demijohn and plug with an airlock and allow to cool completely to room temperature. Once cooled aerate the wort thoroughly by swirling the demijohn with the airlock out, be sure not to let the airlock touch any unsanitised surfaces whilst you're doing this. Once this is complete carefully pour your beer, Fullers 1845 in my case, into a glass and be sure to leave all sediment behind in the bottle with a small slug of beer. Swirl the bottle round and suspend the yeast in the beer and carefully pour into the cooled, aerated malt solution and cap with an airlock. Over the next five or so days remove the bung and swirl the demijohn round to allow air into the solution two or three times a day, this is because the yeast needs oxygen to reproduce and increase the number of viable yeast cells. Make sure not to put the airlock on any unsanitised surfaces whilst you do this, with practice you can hold the airlock whilst swirling the demijohn. Over the next few days a white layer will build up on the bottom of the vessel - that's your yeast. Prior to pitching the yeast syphon off the spent wort and taste it to make sure it doesn't taste sour i.e. it's infected. If all is well add a litre of boiled cooled wort on brewday to wake the yeast up prior to pitching the whole lot into your cooled brew. It's as easy as that!