Thanks for the warm welcome :)
Can you explain why I should leave it a fortnight and keep the temperature lower than is recommended in the kit? The kit says it should be kept at between 21C and 27C. At the mo its at (what I thought was a healthy) 24C.
I'm not questioning your expertise, i'm just fascinated by the whole process and want to learn as much as possible. :)
Until about two months ago, I was brewing Cooper's kits exclusively and enjoying the results. Then I came here and met a lot of long time and expert brewers who explained some things about the process that would improve things for me.
Firstly, high temperatures (especially for some yeasts) lead to the production of fruity esters which are perceived as 'off tastes' and faults. You can also produce fusel alcohols which give headaches and if temperatures get even higher - you can produce REALLY foul tasting beer. Different yeasts are more or less sensitive to temperature, and to be fair, I have had brews get to 24C this summer and they turned out fine, but it is not regarded as good brewing practice. Cooper's being Australian and using their own yeast may be more tolerant of heat, but other yeasts are certainly not. I understand that for a really clean taste, cooler - like 18C - 20C is something to aim for.
Your beer will likely ferment pretty quickly especially if it is a bit warmer, but once the activity in the fermentation vessel (FV) has died down and looks calm, there is still a lot of business going on even when the bubbler has stopped plopping away like it does at the start. Yeasts create other by products besides alcohol and these get cleaned up by the yeast slowly both in the FV and in the bottle or keg.
One obvious advantage of not bottling your beer before DAY14 is that a lot of the yeast in suspension at DAY 7, will have fallen out of the beer and laid itself down as a creamy deposit on the bottom of the FV. This means you get a thinner deposit in your bottles. I have sometimes had 2mm or 3mm of yeast in my bottles. Good luck with pouring a clear pint with that much yeast in the bottle. It's pretty harmless, but it doesn't make the beer look great when you offer it to a mate all cloudy like that. Of course you could get around that by leaving an inch or two of beer in the bottle and chucking that out... But that never appealed to me for some reason. :)
Ferment it on the cooler side if you can and let it stand a fortnight in the FV and you will get a cleaner, clearer product in the end.
Carbonation will also be much better if you can leave it in the bottle a while. A month would be good. Two weeks in the warm for the secondary fermentation and another two weeks in a cooler environment. It REALLY will make the beer much better, but I do realise the awful temptation to start drinking the beer as soon as it tastes remotely like beer. It's a question of whether you drink good beer, or poor beer.
There are plenty of REAL experts on here who will advise you (not me). You can learn a lot from them and before you know it, Clibit will have you buying grain and hops and brewing your beer in a cheap 15litre stock pot on the stove top..... When you get there (and it likely won't be long) you will find a new world of wonderment and great tasting beer that you can adjust and perfect yourself. Better still, you can make it for about 27p to 30p a pint and it is FAR better stuff.
Great hobby, and a great forum.
