Diacetyl Rest

[kramla]

Hi fellow homebrewers
Have just started brewing again after 7 years & reading through the forums has been great, have learnt more in 3 weeks than I ever knew, but then came over diacetyl rest - what is it?

For my second brew I have put down a Tooheys Draught beerkit with a saflager yeast & I have noticed in the forums that when using lager yeast
you need to do this.

Any help much appreciated.

[Aussie Claret]

Hi kramla,
The diacetyl rest is only needed on lagers that are fermented at lager temperatures 10-12c, having used a real lager yeast.

Basically you increase the temperature to 16-20c for 24-48hrs, during the rest the diacetyl is removed from the beer by the yeast. The diacetyl is a by product caused from fermentation at lower temperatures, the yeast will clear it up if the temp is increased. You do the rest in the primary nearing the end of primary fermentation, you have more viable yeast in the primary, after which you generally rack to secondary then cold condition 0-2c.

The diacetyl gives the beer a toffee or butter scotch flavour I beleive, that is considered an off taste in a lager.

AC

[kramla]

Thanks for clearing that up AC, i did some more research on the subject after i posted this & am now a lot wiser.

This site is a wealth of information & i will be here regularly as I to, like many more people these days, have got the HB bug after a 7 year abcense.