Brewing Lager & Temperature

[Hopperty]

It says pitch yeast at 23°c and then to brew at 14°c. How quickly should the 14 be achieved after pitching ? and what would happen if it took a day to achieve that temperarure drop ?

 

[pilgrimhudd]

What yeast is it?

 

[foxbat]

How long depends on your volumes and your fridge temperature. If I finish brewday at 12pm (I start early!) and 24 litres of wort is usually chilled to 21-22 with the immersion chiller then it will be the following morning around 8am when it's down to 12C-ish. I pitch the yeast when it's cold. Wyeast have this to say about it:

Fermentation Temperature:

One of the most common questions we field is, “should I start my lager warm or cold?” The answer depends on how much time you have for your primary fermentation and how clean you want your final beer. The best results will be achieved by pitching at least 12 million cells/mL into cold and well-aerated wort at 48-58 °F (9-15 °C).


If a faster primary fermentation is desired or you are pitching less yeast, then it is best to start a little bit warmer and then cool to the desired fermentation temperature once signs of fermentation are evident.

 

[Hopperty]

I guess the yeast is a "Coopers" as it came with a coopers lager kit.

I don't know how I can simplify the question any more - The instructions with the kit say to pitch the yeast when the 23l of wort is around 23°c and then to brew at 14°c. - I am curious as to the timesacle between pitching and brewing. Can I allow this timescale to be as long as a couple of days or should I attempt to achieve it in a few hours ?

 

[Sadfield]

I would say upto about 15 hours during the Lag phase where there isn't much affect on the flavour profile. Any longer and you're into the Exponential Growth Phase, what we would consider as fermentation.

https://byo.com/article/fermentation-time-line/

 

[Cwrw666]

Pitching a bit warmer than fermentation temperature just gives the yeast a chance to reproduce and get fermenting that bit faster. All yeasts have a temperature range that they're happy with. The lower in that range the actual fermentation occurs, the `cleaner' the result will be.

 

[The-Engineer-That-Brews]

It says pitch yeast at 23°c and then to brew at 14°c. How quickly should the 14 be achieved after pitching ? and what would happen if it took a day to achieve that temperarure drop ?

Sounds like you’re using dried yeast without a starter, so I’d say you’ve got at least 10hrs to get it down to 14° (give or take a couple of degrees). Assuming you’ll be pitching in the late afternoon, I’d say just stand the FV outside overnight. Probably won’t have frozen solid by morning…
Once fermentation starts, keep an eye on it because it will start generating its own heat so the temperature can easily run away. To keep the beer itself at 14° you’ll probably need an air temperature of about 12° once it gets going.
Don’t sweat it though, the beer will be fine even if your temps are slightly off.