DEVON COUNTY AGRICULTURAL COMMITTEE.
CIDER - MAKING
ON THE
FARM
BY THE
County Horticultural Superintendent
(D. MANNING).
Free copies of this Leaflet and advice on all matters relating to Orchards may be obtained from
COLIN D. ROSS, B.Sc.,
Agricultural Organiser,
1, Richmond Road,
EXETER,
REVISED, 1934.
The true value of cider as a wholesome, health-giving
beverage scarcely needs emphasis, its rapidly increasing popularity being
a sufficient criterion of its worth. North, South, East and West in Great
Britain, the consumption of cider has spread into counties, cities and
districts where it was never heard of a decade ago. Still further afield
a considerable export trade has been built up with our Colonies and Dominions
across the seas and the trade bids fair to grow still greater. It should
be realised by the farmer-cidermaker, however, that -(a) this expansion
of the cider industry is almost entirely due to the action of the large
manufacturers in conducting a world-wide advertisement campaign, and -(b)
that what may be called a new generation of cider consumers has been educated
to appreciate a different article from the old type of " farm house " cider.
THE APPLE.
The value of the apple, from either the food or beverage point of view, lies in the composition of the juice, which in itself comprises over 80% of the fruit. The juice holds in solution sugar, malic acid, tannin, a gummy substance, comprising pectose and pectic acid (from which pectin is obtained and used in connection with the making of jams, etc.) and certain mineral salts. From the point of view of cidermaking the important constituents of. the juice are sugar, malic acid and tannin, the vintage quality of the apple depending largely upon the proportion in which these substances are present in the fruit. The dessert and culinary varieties are quite unsuited for cidermaking alone, owing to their lack of character. Sugar and tannin are relatively low in proportion to their acidity, and cider made from such apples is typically thin and coarse. Even varieties like Cox's or Blenheim make very poor cider by themselves. The general practice in cidermaking is to use a mixture of several varieties of apple in order to obtain a blend of the juices, containing as nearly as possible the ideal proportions of the three constituents mentioned above. An exception to the rule is the famous cider apple "Kingston Black" which may be used alone to produce a properly balanced cider. It is the presence of apple sugars in the juice which determine the alcoholic content of the cider, while the acids, besides affecting the flavour considerably, play an important part in preventing secondary fermentation and troubles such as sickness, reaminess, ropiness and oiliness. The tannin, though present in a comparatively small proportion in the juice, is an important constituent. Tannin is considered to affect the flavour, colour and possibly the elusive quality known as the "body" of the cider, while it also favourably affects the keeping qualities and plays some part in the clearing of the juice after pressing.
Varieties of apple suitable for cidermaking are classified into three groups according to the relative proportions of malic acid and of tannin found in the juice when the fruit is pressed:
Group 1. Sharp
varieties, containing 0.45 per cent or more of malic acid.
Group 2.
Sweet
varieties, the juice of which contains little acid (below 0.45 per cent.)
and little tannin (below 0.2 per cent).
Group 3.
Bitter-sweetvarieties,
with juice containing little acid but moderate to large quantities of tannin
(below 0.45 per cent of acid, and above 0.2 per cent. tannin).
An ideal blend of varieties for cidermaking would be one of which the juice on analysis was found to contain approximately from 0.5 to 0.7 per cent of malic acid, from 0.15 to 0.2 per cent of tannin, with as high a sugar content as possible, some juices showing up to 12 per cent. of sugar. For general purposes the following proportions will serve as a useful guide :-
Sweet varieties.- one part by weight of fruit.
Bitter-sweet varieties. - one part by weight of fruit.
Only sorts which ripen at the same period should be mixed,
as an indiscriminate mixture of varieties in different stages of ripeness
will produce an inferior cider. The same varieties, if kept separate and
each milled at the proper stage of ripeness, would produce an infinitely
better result. Although, except under factory conditions, it is more or
less difficult to blend to a definite standard of chemical composition,
it is worth an effort to aim at some degree of standardization by mixing
the varieties according to some definite plan. Personal taste, orthe particular
type of cider desired by the consumer, must determine the actual proportions
of the three classes of apples employed for the purpose.
CIDER.
The quality of the cider produced on the farm depends upon three main points -
(a) The raw material from which it is made.
(b) How the processes of milling, pressing and fermenting the juice
are carried out.
(c) The manner in which the finished product is stored after manufacture.
RAW MATERIALS.
These have been partly dealt with above, but the question of harvesting
and storing the fruit is deserving of consideration. Fruit used straight
from the tree is rarely (except in the case of the earliest varieties)
sufficiently ripe from a cidermaking point of view to give the best results.
It is not sufficiently understood by the farmer cidermaker that the optimum
stage of ripeness immensely affects the quality of the cider as well as
simplifies the processes of fermentation. Green, unripe fruit contains
a large amount of starch which. is prejudicial to a satisfactory type of
fermentation, and, when fermented, produces an alcohol which is often indigestible
and therefore harmful. It cannot be too clearly stated, also, that black
apples are very detrimental to the quality of the cider and that every
black apple going through the mill increases the risk of acetification.
While it is possible to make cider from over-ripe, or even partly rotten
fruit, yet in the first place the quantity of juice is less than that obtained
from fruit in prime condition, and secondly the result is a thin, rapidly
fermenting cider, lacking flavour, body and keeping quality. Apples may
be said to be in prime milling condition when they are sufficiently ripe
for the thumb to be pushed easily into the fruit.
STORAGE.
To ensure that the fruit is milled in the best condition it should be
stored in bulk either in the orchard or under cover in a barn or open shed.
The heaps of fruit should not be more than 2½ to 3 feet deep and
should not rest directly on the soil, whether under cover or in the open.
Apples very quickly pick up any taint and clean straw should be spread
on the floor indoors, while out of doors, if they are to remain any length
of time, the heaps should be made on close hurdles or on a plank foundation
carried on loose bricks. Varieties known to ripen at different periods
should be stored separately ; this is not difficult if the method of gathering
the fruit followed in many districts is generally carried out. The early
droppings are collected at intervals and bagged under the individual trees
; these are ground and treated separately. Long ash poles furnished with
a metal hook are then employed to shake down the remainder of the fruit
as it ripens. Unless the varieties are harvested separately it is almost
impossible to control either the blending or the condition ofripeness ofthe
fruit. Needless to say, cleanliness is of as much importance in connection
with harvesting, storing, and carting the apples to the mill, as it obviously
is in the ensuing processes of manufacture. Prevention is always better
than cure and it is less trouble to keep dirt and deleterious matter out
of the cider than to remove it afterwards.
MILLING.
The old type of cider mill still exists in remote parts of the country.
It consists of a circular trough, hewn out of solid stone, in the deep
groove of which one or two stone rollers run around. The rollers are sometimes
propelled by a horse yoked directly to them, but in the South-Western counties
the horse-gear is outside the pound and the motive power transmitted by
a shaft and gear wheels. Most of the latter are of wood including the teeth,
which can be renewed when worn. A more modern type of mill is fitted with
"tumblers" or "breakers", two deeply ribbed
rollers which revolve in opposite directions, break up the fruit, and the
latter then passes downwards between two other rollers of hard stone. Some
of these mills are turned by hand or by a horse-gear, but with the advent
of the internal combustion engine on the farm many are now connected up
and driven by machinery. The latest and best type of mill, however, is
the one known as a "grater", consisting of a cylinder fitted with transverse,
notched knives revolving at a high speed which literally "grates" the fruit
into a very fine pulp. The installation of such a mill generally repays
its cost in a very short time owing to the higher yield of juice and the
ease and rapidity with which it can be pressed from the pulp.
PRESSING.
The practice of allowing the pulp to stand and "macerate" for a day or so before pressing is still followed in some places, the supposed advantages being easier pressing and a higher colour. It is very doubtful whether these supposed advantages outweigh the certain disadvantages arising from the prolonged exposure of the pulp to the air, and generally speaking the pomace is pressed as soon as it is ground. Presses are of various kinds, ranging from the old wooden screw or "spill" press still in use on many farms, up to the modern hydraulic lift type employed in up-to-date cider factories.. The mass of pulp when built up on the bed of the press is termed a "cheese" and old fashioned methods of building a cheese are still in vogue in some parts of the country. In the South-West "reed" i.e., combed-out wheaten straw, is employed to retain the pulp. The "cheese", so built up, is pressed as tight as possible by means of a windlass or capstan, manned by two lusty farm hands, a chain attached to the end of a long lever being wound on the capstan and the screw thus gradually turned. Horse-gear mills, straw cheeses, and hand manipulated presses, however, all really belong to the age of reaping hooks and threshing flails.
The modern plant combines washing apparatus, elevator, high speed mill, hydraulic press and a pump to convey the juice to its destination, all in one outfit. The motive power is supplied either by an electric motor or an internal combustion engine, combining a saving of space, time and labour, with high efficiency and an increased output. Wherever a "grater" mill is employed, cloths and drainage racks are essential to retain the pulp when building the cheese. Cloths may be of horse-hair, coco-fibre, manila-fabric or of Egyptian Cotton. The first named is far too close in texture, heavy to handle and difficult to clean, while although lasting a long time the initial cost is too high and this material is going out of favour. The same arguments apply in a less degree to the coco-fibre and manila fabric. Egyptian Cotton cloths are more popular, being light, strong, and easily cleaned.
The cheese is built up as follows :-A light "frame" of
the desired dimensions and about 4 inches deep is placed on the bed of
the press. A cloth about twice the width and length of the frame is spread
over this and a sufficient quantity of pomace placed in the cloth to fill
the frame. The cloth is then folded over from sides and ends, and the frame
removed. A drainage rack, composed of narrow laths with spaces between,
is then placed on top of the first cloth and the process is repeated until
the cheese is built to the required height. Care should be taken to build
evenly and vertically. Pressure is applied until no more juice can be extracted,
the cheese is then pulled down, the dried pomace shaken out of the cloths
and the latter are ready for the next cheese. It should be noted that a
"grater" mill with a hydraulic press will extract on an average 10% more
juice from a ton of apples than can be obtained by the older methods, while
even a small plant will grind and press a cheese in 30 minutes.
THE TREATMENT OF THE JUICE.
The transformation of the juice of the apple into cider
is mainly brought about by a process known as fermentation which consists
of the conversion of the natural sugar into alcohol with the liberation
of carbonic acid gas in the process. This change is brought about by the
action of extremely minute plants which, being present on the skin of the
apple, enter the juice when the latter is pressed out. These minute organisms,
collectively known as "yeasts", feed on certain constituents in the juice
(principally nitrogenous compounds), and secrete material which attacks
the sugar. The process is not a very complicated one and should be clearly
understood by the cidermaker. If fermentation
is allowed to continue naturally all sugar will eventually disappear and
a "dry" cider will result, the alcoholic strength of which will depend
upon the percentage of sugar originally present in the juice. If a sweet
or medium sweet cider is desired, some method must be employed to control
the fermentation and arrest it when the required point is reached. The
progress of the fermentation can be followed by ascertaining and recording
the percentage of sugar in the juice from time to time and noting the rate
of its disappearance.
KEEVING.
The practice of transferring the juice from the press
into large open vats or into partly filled casks and allowing a "crust"
to form is known as "keeving" This method is seldom necessary where modern
mill and press are employed as the juice runs clear from the press and
may be placed direct into casks to ferment. Where tumbler mills and straw
cheeses are still in use the juice generally contains a considerable amount
of suspended matter and "keeving" is advisable.
Keeving often has also the effect of reducing the rate of fermentation
by reason of the rapid growth of yeast on the exposed surface of the juice
robbing the latter of an appreciable amount of nitrogen. It is essential
that the keeved juice is drawn off at the right moment, i.e., just as the
crust begins to crack and show the white froth which indicates that fermentation
has commenced. Cidermakers know that a slow fermenting juice generally
indicates good keeping quality, but this advantage of keeving is thrown
away if the juice is carried in buckets and poured into casks or in any
way aerated. This aeration has a stimulating effect upon the yeasts and
tends to encourage a more rapid fermentation.
FERMENTING.
On the farm the juice is transferred either direct from the press or via the "keeve" to hogsheads, pipes or vats to ferment. It cannot be too strongly emphasised that all casks, etc., should be scrupulously clean both outside and inside. Apple juice, like the fruit itself, has an almost uncanny faculty of absorbing odours and flavours from anything with which it comes in contact and it is impossible to remove or "camouflage" a musty or caskyflavour if allowed to develop in the cider. Casks may be cleaned by steaming, washing or chaining in most cases, but some require the removal of the head and a vigorous scrubbing with strong hot soda water. Any cask in too bad a condition to be cleaned by one of the above methods would be better chopped up and burned. While it is difficult to clean a cask it is quite a simple matter to ensure it remaining sweet and clean when not in use. It may be thoroughly washed and stored perfectly dry, or better still, half a pint of bi-sulphite of lime diluted with two gallons of water should be placed in the cask and bunged down tight. The cask must be emptied and rinsed with clean water before being used again.
In order to be able to follow and record the progress of the fermentation, the cidermaker should provide himself with a simple instrument known as a hydrometer. This is similar to the one used for storage batteries connected with electric light plants except that the scale should register from 1.000 to 1.060. A word of explanation here may be helpful. The purpose of a hydrometer is to ascertain the relative density of any liquid in comparison with water. A hydrometer when floated in pure water will show 1.000 on the scale and this is taken as the standard. If, for instance, the hydrometer when placed in the fresh apple juice floats high enough to show the figures 1.060, this is said to be the S.G. (Specific Gravity) of the juice. In simple language this means that if a certain quantity (approx. 100 galls.) of water weighs 1,000 lbs., the same quantity of that particular juice would weigh 1,060 lbs. This extra weight or density of the juice is mainly due to the natural sugars from the apples. By dividing the last two figures of the reading by 5, the approximate percentage of sugar may be roughly estimated, e.g.,
The early stages of fermentation should cause an extrusion of froth
and some crust from the bung-hole but when this stops
it only indicates that the preliminary stage is over, not that the
fermentation has ceased. As soon as this occurs, generally within a week
or so, steps should be taken to prevent an undesirable form of fermentation
taking place, which, if allowed to continue, will convert the alcohol into
vinegar and thus spoil the cider.
This form of fermentation (known as "acetification") is caused by bacteria or minute organisms which can only carry on their work in the presence of air and at a relatively high temperature. While the fermentation is rapid, the large amount of gas given off prevents acetification taking place by excluding the air from the surface, but when the process slows down other means must be employed to ensure the absence of air. The best method is to use a cork bung through the centre of which a glass tube is passed. This tube is either bent over and the end inserted into a vessel containing water or else it is bent into a complete loop with two bulbs blown out, on opposite sides of the loop. The bulbs and the U shaped tube between them are filled with water. Whichever type is used forms a complete airlock to the cask, although allowing the gas arising from the fermentation to escape freely. The rate of fermentation can be roughly gauged by the rapidity of the bubbles of gas passing through the water. Any cider or froth which may be spilled around the bunghole should be wiped away with a clean cloth or this will also increase the risk of acetification.
If a dry cider is desired all that, is necessary is to allow the fermentation to proceed naturally until it almost ceases, when the cider is transferred to a clean cask and bunged down until required for consumption or sale. There is no doubt, however, that the type of cider in greatest demand to-day, and this is true even within the cider producing area, is one with some degree of sweetness. Although a naturally dry cider can be sweetened to taste, yet the true flavour of the original apple sugar is infinitely preferable. When it is remembered that the action of the yeast in causing the fermentation is responsible for the disappearance of the sugar from the juice, it will be easily seen that some method must be adopted to rid the cider of this disturbing element if the natural sweetness is to be retained to any degree. There are three methods by which the farmer-cidermaker may attain this object :-
Racking.- This consists of drawing off the cider into clean casks preferably after a spell of cold weather which causes the yeast to become dormant and sink to the bottom of the liquid. Racking is best done by means of a pump, or by the use of a siphon, when it can be arranged that the fresh cask is at a lower level. If a racking tap is employed there is a risk of the passage of the cider through the air stimulating a fresh fermentation instead of checking it. If racking is relied upon, it may be necessary to repeat the operation once or twice, a general time-table being as follows :-
2nd Racking. -4 weeks later.
3rd Racking. -6 weeks after the second.
Since January, 1927, when new regulations came into force, it is forbidden to expose cider for sale containing any other preservative than Sulphur Dioxide. This material may be introduced (a) as a gas, (b) in liquid form, (c) as crystals.
Filtering has for its object the removal of the yeast plants from the juice which passes from the filter into clean casks in a perfectly clear sparkling condition and is bunged down till required.
If it is desired to produce a sweet cider, the point at which the fermentation should be checked or arrested may possibly be decided by personal taste.
The determination of the degree of sweetness will be obviously more exact if the hydrometer is employed to ascertain the progress of the fermentation. No fixed period after making can be indicated for treating the juice to stop fermentation as some ciders ferment much more rapidly than others, some may be ready in a fortnight, while others may take months to reach the desired point. The.following hydrometer readings, (i.e., Specific Gravities of the juice) may be taken as suitable points for arresting fermentation according to the type of cider desired.
Filtered at Specific Gravity of 1.015 to 1.025 - Medium sweet.
Filtered at Specific Gravity of 1.000
to 1.015 - Dry Cider.
The storage of cider after the fermentation has ceased
naturally or has been artificially arrested by one of the foregoing methods
necessitates extreme care if transformation of the alcohol in the liquid
into vinegar is to be avoided. With the cessation of the fermentation the
protection afforded by the gas is no longer available and precautions must
be taken to exclude the air as much as possible and maintain a low, even
temperature in the store house. No air-lock is now required but the casks
should be completely filled and all wastage caused by evaporation through
the wood made good from time to time. A better type of bung than the cork
one wrapped in sacking generally used is a long tapered wooden bung made
of apple, ash or similar hard wood of such a size that, when driven in,
the small end dips into the cider and prevents the bung shrinking and allowing
air to enter the crevices. It will be realised, also, that it is an advantage
to make all the bung-holes of one uniform size. When bunged down tightly
the fermentation proceeds very slowly and the cider charges itself with
the gas produced in the maturing process, which may continue throughout
the following summer or even over a longer period.
BOTTLING CIDER.
The question of bottling cider largely depends upon the purpose for which it is required. If the bottled cider is required for consumption over an extended period, then the champagne type of bottle should he employed. These can generally beobtained at a moderate cost from dealers and should be thoroughly cleaned before being used. The bottles should be filled nearly full by means of a rubber tube used as a siphon, the end of the tube being dropped to the bottom of the bottle to ensure that the cider is not aerated or disturbed in any way. Corks should be of the best quality, steeped in warm water before use, and should be secured by wires, after which the bottles should be stored on their sides to prevent the corks shrinking when dry.
With reference to the bottling of cider for storage, the best time for this is generally during the month of April following the making. However, no two ciders are exactly similar in respect of the rate of fermentation and it is well to test each sample by the following method before bottling a quantity.
With regard to the screw-stoppered bottle, cider may be bottled in this
way at any time of the year provided the fermentation has practically ceased
or has been stopped artificially. It is necessary to bottle a whole hogshead
or pipe at one operation, but it is not advisable to bottle by this method
long in advance of requirements.
DISORDERS AND TROUBLES OF CIDER.
Acetification-
This is the term applied to cider in which the alcohol is wholly or
partly converted into vinegar, or, as the farmer terms it, the cider has
"gone off". This conversion is affected by a micro-organism present in
all ciders which, under favourable conditions, develops into the growth
known variously as "mude", "mare", or "mother" of vinegar. As this organism
can only develop in the presence of air and warmth, prevention is a practical
proposition. Every effort should be made to keep the cider cool and airtight.
Storing casks in an upright position is a fruitful cause of acetification
as the head shrinks on drying and allows the air to enter.
Treatment of Acetic Cider-
It should be clearly understood that prevention is better than cure.
The formation of acetic acid (vinegar) cannot take place if casks are kept
full and air-tight at a low temperature. If, however, in spite of precautions,
cider becomes acetified later in the season it may be kept until cidermaking
time comes round again. A "cheese"
or "mock"
after pressing is then broken up and soaked for twenty-four hours in the
sharp cider, after which the pomace is re-pressed. The juice is then fermented
in the ordinary way, the only point being that the resultant cider should
be used as soon as possible. Cider will often go off, i.e., turn sour,
if a cask is a long time on tap owing to the entry of air as the cider
is drawn off. Commercially this is prevented, both in the case of storage
vats and hogsheads on licensed premises, by the periodical introduction
of carbonic acid gas from a cylinder kept for the purpose. Where this is
not practicable, however, another method may be employed. A small quantity
of purified medicinal paraffin is poured into the cask, this forms a
film about ¼" thick over the cider, thus excluding the air
from it and effectively preventing acetification. When the cask is nearly
empty the paraffin can be drawn off and used again.
Cider Sickness-
A cider will sometimes turn "sick" during hot summer weather, the trouble being characterised by a thick cloudy appearance, a rapid secondary fermentation with the risk of bursting bottles or casks, a heavy deposit and the cider becoming unpalatable. The "sickness" is due to the action of a bacterial organism upon the sugar content of the cider, thus the sweeter and richer the juice the greater the danger of this disorder. Conditions which favour the development of sickness are-(a) high temperature, (b) low acidity. The trouble seldom develops at a lower temperature than 50º Fahr.
With regard to acidity, it is very rare that sickness develops in cider
containing 0.5% or more, of malic acid. Hence, if attention is paid to
blending the apples to ensure a sufficient acidity and to storing the cider
in a cool even temperature, the risk of trouble is minimised. It should
be noted that cider sickness is contagious and all vessels and appliances
which have been used in connection with affected cider should be steam
sterilized,
Treatment of " sick " cider.
If not too far advanced, cases of sickness may be treated by either
increasing the acidity or re-fermenting the liquor. The acidity may be
increased by blending with a sharp cider or by adding sufficient Citric
or Tartaric Acid. To re-ferment the liquor, use about ½ gallon of
thick brewer's yeast per hogshead, well washed before use. Fermentation
is then allowed to proceed until the Specific Gravity has been reduced
5 or 10 points when it should be stopped by filtering.
Oiliness, Ropiness and Reaminess.
As with cider sickness these disorders occur most frequently with cider
containing low proportions of acid and alcohol, especially when sugar has
been added to the juice. The cider becomes cloudy and changes into a viscous
oily liquid.
Treatment of oily cider.
If the disorder is not very far advanced it is sometimes sufficient
to pour the cider into open vessels, stir it vigorously for some time,
transfer it to closed casks to settle and rack or filter from the deposit.
More severe cases should be treated by using a clearing agent as Kieselguhr,
Tannin and Gelatine, or Kaolin (China Clay).
Blackening.
The liability of cider going black on exposure to the air is almost entirely due to iron compounds in the juice. The risk of blackening may be reduced to a minimum if great care is taken to prevent iron from entering the juice from the mill. Iron shovels, iron buckets, soil which may be rich in iron, adhering to the fruit, etc., are all potential causes of "blackening".
If one pound of Citric Acid (lead-free) is dissolved in water and added to a hogshead of cider which has gone black the natural colour may often be restored.
NATIONAL FRUIT AND CIDER INSTITUTE,
LONG ASHTON,
BRISTOL.
Other leaflets dealing in more detail with the subject of cidermaking are issued by the above Institute. Practical advice and help is also readily available at all times on matters relating to cidermaking to anyone communicating with the Director.
The writer has been in close touch with the Institute since 1911, and wishes to acknowledge his indebtedness to the members of the Staff for their invaluable help, without which this leaflet could not have been written.
Visits are organised to Long Ashton annually, in May,
particulars of which may be obtained from the Agricultural Organiser, 1,
Richmond Road, Exeter.