Methods
For those of you a little apprehensive, I'd like to offer a little assurance...
Fruit Selection and Processing
The advantage of a small, manual, operation is that fruit can be individually quality controlled. The first stage of processing, is manual washing, at which point any bad fruit can be immediately discarded. Most domestic setups require chopped (typically quartered) fruit for crushing/juicing, providing an opportunity to look at the insides of the apples you use. Totally organic domestic fruit will almost inevitably contain a certain amount of insect life. For this reason, avoid juicing fruit whole and cut out any bruised, rotten, insect damaged and otherwise undesirable bits.
Hygiene
My golden rules are:
- wash your hands
- follow manufacturer's guidelines
- sterilise your vessels
Bottle brushes and larger variations for demijohns and kegs are easily available and cheap. The procedure for hygienically cleansing equipment is generally:
- scrub (visible)
- disinfect (invisible)
- rinse (away disinfectant residue)
Campden tablets and chlorine-based sterilisers are commonly used; baby bottle sterilising solution is my preference. You have to be careful with wooden equipment, such as presses and barrels; excessive use of detergent would taint juice and impede fermentation. A thorough hosing followed by salt-water treatment might be more appropriate here.
Finally watch out for orchards where animals graze - take extra precautions in washing fruit in this case.
Additives
I'm more comfortable with cider made from apples, rather than with them. A recent study of UK Cider content found that typically commerical ciders contain only 30% juice - the rest being diluted syrup! Anyway I avoid adding anything at all, as a member of CAMRA I subscribe to the real ale philosophy - consequently my drinks have a unique character, if only a short shelf life. The secret to this is careful manual processing and monitoring of the fermentation process, I'm happy to advise on this, but there's not room here to go into detail.
In your own brews you may be more comfortable to sterilise juice before adding a cultured yeast; this is often done with Campden Tablets (Sodium Metabisulphite, E223) and called Sulphiting. If your using freshly pressed juice, then there is rarely requirement to add yeast nutrient or sugar. Some people prefer sweeter ciders, so they add non-fermentable sweeters such as Saccharin or Aspartame, my preference is simply to stop fermentation earlier.
Alcoholic Content
During fermentation sugar is converted into alcohol affecting the liquid's Specific Gravity. By measuring this change with a hydrometer it is possible to monitor the progress of fermentation and the percentage of alcohol produced.
| (OG - FG)f = %ABV | |
|---|---|
| OG | Original Gravity (before fermentation) |
| FG | Final Gravity (post fermentation) |
| f | yield factor - varies with strength |
| ABV | Alcohol by Volume (expressed as percentage) |
The yield factor, f, varies since sugars can be used in yeast reproduction as well as respiration.
| OG - FG | %ABV | f |
|---|---|---|
| 26.2 to 36.0 | 3.3 to 4.6 | 0.129 |
| 36.1 to 46.5 | 4.6 to 6.0 | 0.130 |
| 46.6 to 57.1 | 6.0 to 7.5 | 0.131 |
| 57.2 to 67.9 | 7.5 to 9.0 | 0.132 |
As if this isn't complicated enough, when blending you have to work out the relative preportions. Alcoholic Units are commonly used these days, where a single unit represents a litre at 1% ABV. A pint, being 568ml, can thus be calculated as 568 / 1000) x %ABV (roughly ½ %ABV). Typically my cider comes out at around 5 or 6 %ABV (about 3 units), but each batch is unique.