Mixing & Aeration

Before emptying the cans in your fermenter, first add some boiling water to the fermenter, this will help the malt extract mix in more easily and not just stick to the bottom.

When adding the water to top up, try your garden hose with a good nozzle to provide lots of aeration. Run the hose for a time before, to make sure that any residue from the hose pipe is flushed through.  Vigorously swirl the extract and water mix as you top up the fermenter.


Yeast

CST uses S04 yeast as we have found this provides the best flavour and fermentation.  For the first brew create a yeast starter.  This takes 24hrs and you need a packet of S04 initially added to a glass of water at about 38 deg C and rehydrate the yeast for 20 mins.  Add this glass to 113g of light spray malt to create about one litre ‘starter’ (1040 OG).  Keep this at 20 deg C and stir regularly to aerate for 24 hours. Aeration is very important. (see detailed research). Keep this in a covered (sterilised of course) container, ideally in your temp controlled fermentation unit (see temp control below).

CST re-uses this yeast for the next brew immediately after emptying the fermenter.  Scoop out the yeast residue and keep it at 20 deg C, covered.  Pitch this into the next brew asap.  This means following one fermentation from the last.  CST uses the same batch of yeast up to 4 times. (see the detailed research links on yeast).


Temperature Control & Fermentation

Temp - This seems to be a crucial aspect for quality results.  CST ferments at 18.5 deg C.  See the detailed notes on building a temp controlled units.

The general information on most kits is rubbish. Fermentation takes much longer, at least two weeks and will stick at 1020 if you don't use a yeast starter. It is also important to note that the end stage of the fermentation changes the 'character' of the beer as the yeast uses the unwanted by-products and improves flavour. Adding dry hops towards the end of the fermentation is also important to get the right flavour. See detailed research links.

Using a quality, large scale hydrometer, fairly accurate reading can be made. Remember to take the reading from the bottom of the meniscus. CST has yet to get ANY fermentation to below 1011 FG. Often it's higher, but this seems to make little difference to flavour. CST takes more account of the time and flavour of the fermentation, agitating the fermenter after a 6 days and again after 10 days seems to help keep the fermentation going.


Additions

Hops, spray malt, lactose sugar, chocolate (nibs), fruit, honey etc. can all be added to create different flavours.  See the detailed research links on this topic.


Bottles or Barrels

These give different results.  Barrelling seems to mature the beer quicker and is easier.  Some bottles take many months to mature well.  Bottles keep for a year plus, barrels for many months.

For both, first drain your initial fermenter into a second fermenter for bottling or a clean (warmed) barrel using a short hose to minimise aeration.  Add to the secondary brewing sugar or spray malt (80g to 100g) by tapping off some beer into a jug containing a solution of the brewing sugar/spray malt (use minimum boiling water to make the solution).  Add in this sugar solution to the second fermenter/barrel in stages to provide a good mix.  Keep this whole process as ‘quiet’ as possible to minimise aeration.  If bottling you shall need the right tap on the fermenter or barrel to give an easy and controllable flow into the bottles, don’t try to use the ‘little bottler’ gadget as it is far to slow!   Cap the bottles with the ubiquitous Crown capper.

You can of course bottle part and barrel part of one batch.  After barrelling and drinking, you may choose to bottle the last bit if you need to re-use your barrel, just add a small teaspoon of brewing sugar to each bottle. Bottling allows varying the result, eg adding some lactose sugar to a few bottles (which does not ferment but adds ‘mouthfeel’).

The biggest issue with barrelling is how to keep your barrels at a decent temp.  Bottles can be stored in a dark cool place (sunlight and fluorescent will ‘skunk’ your beer quickly), then put in the fridge before drinking.  CST usually prefers a cooler pint (but this is to personal preference).  See the detailed notes on building a barrel ‘temp controled cupboard’.

Overview of Key Issues