10 Day Rule?

[martyn142]

I have a Coopers IPA made with 500g DME and 300g brewing sugar which has been in the FV for 7 days and seems to have finished (below 1010 and stable). Now I've read several times on here that it is a good idea to do the primary ferment for 10 days as this is the optimum for imparting the flavours from the yeast. What are the opinions? Better to leave it or get it in the barrel as soon as it has finished the primary?

[sparky Paul]

I look for 2-3 days of constant readings to confirm that fermentation has finished. If the beer is still very murky, I may leave it another day or so to clear down a bit, otherwise I bottle it immediately.

You don't want to to be leaving your beer on top of dead yeast any longer than is necessary. It can impart an unpleasant taste to the beer, unfortunately I know this from experience...

[martyn142]

OK Paul tanks. Into the barrel it goes this arvo.

[stevezx7r]

The ten day idea is down to the by products produced by the yeast while making alcohol (and c02), specifically, diacetyl. If you were to allow the yeast to ferment in say three days their will be some of this diacetyl still around in the beer. Some beers benefit from small quantities of it so the brewer will allow for this whereas others try to avoid it. The ten days rule is to allow the yeast to clear up after itself as once it's done making beer it then eats the diacetyl too.