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THE SCIENCE OF CIDERMAKING

Part 1 - Introduction

There has been a tremendous resurgence of interest in cidermaking overthe last few years. There are probably well over 400smallcommercial cidermakers in the UK in addition to the wellknown names of Bulmers,Gaymers and Magners - and a general interest in all things 'green'has fostered the growth of small-scale cidermaking. Bulmers arenow owned by Heineken, and Gaymers by Cantrell and Cochrane of Ireland.Magners is also part of the C&C group. Thatchers, Westons,Aspall and Aston Manorare other larger independent UK cidermakers. In other parts ofthe English speaking world such as North America and Australasia therehas been a similar revival of interest.

Anyone wanting to make cider on a small scale is often presented withmisleading dogma and half-truth which is confusing and misleadingto the novice, and sometimes seems to result from an almost wilfulignorance ofthescientific principles of cidermaking. In part, this stems from agenerallack of accessible information about the subject. Since the Long AshtonResearch Station closed its Cider Section in 1986 there has been no'official'source of advice for UK cidermakers, and there have been few reliablebooks on the topic. With the rise of the internet, cidermakinginformation has become more accessible, but much ofit is misleading and some of it is just plain wrong! This seriesof articles tries to fill the gap and to put thescienceof cidermaking into its proper perspective, so that potentialsmall-scalecidermakers can make their own choices from the options available.Thereare, after all, as many different ways of making cider as there arepeoplewho make it.

Definition and History

First of all, what is cider? In the UK it is understood (and legallydefined)to be a beverage made "wholly or partly from the fermented juice ofapples".Similar words (cidre, sidra) are also used in France and Spain. InGermanyand Switzerland, although cider is made there, there is no specificwordand the term 'Apfelwein' is used instead. In the USA and Canada,'cider'commonly refers to a cloudy but unfermented 'farmgate' apple juice,unlessqualified by the term 'hard cider' to denote that it has beenfermented.The word 'cider' itself is supposed to be derived from Greek or evenHebrewsources and simply means 'strong drink', although a millenium of usagenow ties it in with apples.

Presently, most commercial cider is made in the UK (ca 100+milliongallonsannually) followed by France, Ireland, Spain, Germany and Switzerland.Productionin other countries is small but in North America and Australasia is rapidly increasing. Although cider seems to have beenmade in the Mediterranean basin around the time of Pliny (1st centuryAD),it became well-established in Normandy and Brittany in early medievaltimes(from 800 AD onwards), probably arriving there from the Atlantic coast of Spain . Shortly afterwards it seems to have taken holdinBritain, and the first mention of established production in thiscountryis from 1205.

Although cider was once made all over the UK even as far north asYorkshire, the centre of UK cider production is now in a bandstretchingnorthwards from Devon, through Somerset, Gloucestershire,Worcestershireand Herefordshire, with sporadic local operations in Suffolk, Kent,Sussex, Berkshire and the Midlands. In the 17th and 18th centuries itseemed to have reachedsomethingof a zenith, with cider being compared to the best French wines andexportedfrom the West Country to London. A number of manuals on the subjectwerepublished at this time, including Worlidge's famous 'Vinum Britannicum- a treatise on Cider and Perry'. John Evelyn, the diarist, politicianand arboriculturalist, published his 'Pomona' in 1670, which discussesfruit growing in general and cider making in particular, and includescontributionsfrom authors throughout the country. This book (part of his epic'Sylva')went through several editions and is still available in facsimiletoday.

Cider did not seem to last as a serious competitor to wine(possiblydue to punitive taxation), and by the end of the 19th century it seemsto have been made without much care on most West Country farms. It wasoften considered as part of the labourers' wages, particularly atharvesttime when last season's cider would be consumed. The growth of railtransportand bottling technology, however, enabled a new market to beestablishedin towns and cities throughout the 20th century, dominated by a fewlargemanufacturers. From the 1990's there has been a new divergence, between themass-market producers on the one hand and the smaller specialistproducerson the other. This website and series of articles is mostly concerned with the cider made by smaller 'craft' producers.

The Fruit

It has to be said that cider of a sort can be made from almost any typeof apple. In Suffolk, Kent and Sussex, surplus dessert or cookingapples are used with great success. In Germany and Switzerland,littledistinctionis made between dessert, cider and juice apples and the ciders are veryacceptable locally although somewhat thin and acidic to an Englishpalate.In North America there are some traditional cider varieties with highertannin levels such as Golden Russet and Hewes Crab, and some newer oneslike Redfield, but most ciders there and in Australia and New Zealandare made from surplus dessert apples.

Despite this, much of the present mystique of cider makinglies withthe selection of 'true' cider apples - that is, those cultivars grownforno other purpose. In the West Country and in Northwest France, wherearguablythe finest ciders are made, these are centred on the high-tannin'bittersweet'and 'bittersharp' varieties (if low in tannin, these arecorrespondinglydescribed as 'sweets' or 'sharps'). Since these are generallyunavailableon the open market except in glut years ,anyone planting a new cider orchard would be well-advised to go forthese'true' cider apples. Not only do they have the extra 'body' and 'bite'due to high tannin, but they also press much more easily than dessertapplesdue to their fibrous structure. Some of these varieties, at least, alsopossess the elusive character of 'vintage quality' which sets apart thebest cider from the run of the mill. But if you do not have theseapples,do not despair - just make sure you select full flavoured dessertvarietieslike 'Cox' and 'Russett' rather than 'Bramley' and 'Golden Delicious',with a modicum of crab apples (to supply the tannin) if you can getany.

A word about 'tannin' is probably in order here, since it issofrequentlymentioned in connection with cider and yet is so frequently confusedwithacidity. This is perhaps because in most 'crab' apples (which are not atrue species, merely domestic apples which have gone wild from seed)bothacidity and tannin are high. Acidity is easy to understand - a lemonprovidesa good example of this. Tannin is exemplified by the mouth-puckeringtasteof strong tea, or by the taste of a sloe - it can be both bitter and/orastringent ('hard' or 'soft'), depending on its chemical structure andmolecular size. In cider making, we need both tannin and acidity inmoderateamounts, as will appear later. The other major component we need issugarto ferment into alcohol. This can of course come in a bag from Tate andLyle but is better for our purpose if it comes from a bittersweet ciderapple!

Cideris made only from apples, with a possible admixture of pears.Other so-called ciders which are made or flavoured with other fruitsand herbs are not ciders at all. At best they are fruit wines(known legally as 'made wines') and at worst they are alco-popsfor indiscriminating and generally young drinkers. You will not findany advice on how to make such products here. Nor will you findany 'recipes' on this website. Cider is not a beer and the concept of'recipe' does not apply to cider.

Milling and Pressing

Whatever kind of apples are used, they must first be milled to a pulpbeforethe juice can be pressed out. This is rather different from winemakingwhere the grapes need only a light crushing to break the skins beforeexpressingthe juice. Traditionally, apple milling was done in a circular stonetroughby a rotating stone wheel drawn round by a horse. From the 18th centuryonwards, roller mills based on two closely spaced but contra-rotatingshaftswere used, either hand or steam powered. Resourceful people havemanagedto adapt domestic mangles for this purpose, fitting the rollers withstainlesssteel screws to break up the fruit! Scratcher or grater mills, in whicha wheel bearing coarse knives or graters rotates against a fixedsurface,are also popular and form the basis of the high speed mills used inmostmodern cider factories. Domestic versions of this mill are alsoavailable.At worst, a food processor or a thick lump of timber may be used tosmashthe fruit to a pulp, or a rotating blade ('Pulpmaster') may beharnessedto the end of an electric drill.

To extract the juice from the pulp, wooden screw 'pack'presses wereused from medieval times onwards. The apple pulp had first to be builtinto a 'cheese' using alternate thin layers of pulp and straw. Pressurewas then applied to the cheese, the straw providing drainage channelssothat juice could flow to a receiving tray and thence to a barrel as thecompressed pulp diminished in volume. This principle is still used inmanymodern cider presses, large and small. The straw has long been replacedby wooden slats and terylene cloths, and the pressure is provided by anhydraulic pump, but the principle of making the cheese still remains.Small-scaleversions of this press are readily available from specialist suppliers.

In the horizontal piston press (Bucher-Guyer) which is nowused inlargecider factories, flexible nylon drainage channels are providedthroughoutan enclosed steel cylinder which is filled with pulp and graduallycompressed.New types of belt press, where a thin layer of pulp is squeezedcontinuouslybetween two endless woven steel and nylon belts, were originallydevelopedfor sewage sludge dewatering, but have recently become popular incommercialjuice and cider factories! A modern but smaller alternativefor the hobbyist is the 'bladder press' which is driven by mains waterpressure alone.

Small-scale basket presses are relatively cheap and widelyavailablefor domestic use, being commonly used for grapes, but they do notalwaysgive good juice yields on apples because no allowance is made fordrainagechannels in the pulp and not all the juice can find a pathway out.Problemswith 'slimy pulp' will be discussed in a later section.

The interval between milling and pressing is nowadays keptveryshortby most cidermakers and is usually only a matter of minutes, the pulpbeingfed straight to the press. However, this was not always the case intraditionalcidermaking, particularly in France, and various interesting and usefulenzymic changes take place if this period lasts for several hours('cuvage').Similarly, the way in which the juice is treated before fermentation('keeving')can also have important implications for cider quality. These aspectsareconsidered in a later article.

Fermentation and storage

Once the juice is expressed, the 'new traditionalist' and the largecidermaker tend to part company. The 'new traditionalist' addsnothing,doesn't interfere with the natural course of fermentation at all, andisquite at the mercy of the wild yeast and bacteria that get to his juicefirst! The factory cider maker manipulates the processcompletely,adds cultured yeast and sugar syrups to ferment to a high alcohol 'base', and has total technical control!

The 'new traditionalist' may by good luck produce a superbcider butall too often it is acetic, murky, full of strange odours and reallyquiteunpleasant to drink, except to the committed fanatic or to theunsuspectingtourist who expects no better of his 'scrumpy'. The factory makeralwaysproduces a consistent product, but it is bland and undistinguished,competingwith the lager market in suburban pubs and clubs. Somewhere betweenthesetwo extremes lies the middle ground of highest quality where thesmall-scale'craft' cider maker is aiming to operate and which these articles are intended to help.

Whether traditional or otherwise, certain features shouldremain thesame. The right sort of yeast must be present, and must dominate otherless desirable organisms. There must be sufficient nutrient in additionto sugar for the yeast to grow, it must convert much of the sugar toalcohol,and it must generate desirable flavour characteristics as it does so.Afterfermentation, most or all of the yeast should be removed and the cidershould be stored in the absence of air, protected from spoilage yeastsand bacteria. Otherwise it acquires peculiar off-flavours andeventuallyturns to vinegar.

Exactly how we achieve these objectives is the subject of thefollowingarticles. To conclude this introduction, we list an outline flow chartfor cider making, with options which any individual cider maker maychooseto exercise as he wishes. These options are discussed in detail as theseries proceeds.

Flow Chart for Cidermaking
MAIN PROCESS	OPTIONS
APPLES	Varietal selection Nutrient levels
HARVEST	.
STORAGE	Fruit blending
WASHING	.
MILLING	'Cuvage' of pulp Pectinase addition
PRESSING	Keeving Pectinase addition pH (acidity) adjustment SO2 addition Yeast addition Nutrient addition
FERMENTATION	Use of concentrate Addition of sugar
RACKING	Malo-lactic fermentation SO2 addition Natural (arrested) sweetening.
STORAGE IN BOTTLE OR CASK	Fining Filtration Added sweetener and preservative SO2 addition Pasteurisation

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