making is more of an art than cider making'
This page is designed to be read in
conjunction with the cider making guide. The basic processes
of cider and perry making are very similar, however
the differances are important. References and comparisons
will be made to the cider making process throughout
this description of perry making.
page is organised into several sections. The principle
stages of the fermentation are described, followed
by an overview of the cider making
process, a discussion of the characteristics
of the pair juice, the microbiology
of the process, the changes in
the composition of the perry during fermentation,
and finally a description of how to
make your own perry.
cider making, you do need to know some of the technical
detail to make the best possible perry. Research into
perry making is less well advanced than into cider making
so the depth of detail is not so pronounced. For this
reason perry making is more of an art than cider making.
a further reading section at the end if you want to
While the current editorial team will be more than glad
to have your feedback; please be aware that this was
written by Gillian Grafton not by the current editors!
This document is as accurate as Gillian made it, but
you're on your own - we don't accept any liability for
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is made from pear juice which has undergone two different
kinds of fermentation. The first fermentation is carried
out by yeasts which have either been added deliberately
or which are naturally present on the pear skins. This
fermentation converts sugars to ethanol and the higher
alcohols (fusel alcohols). The second fermentation,
the malo-lactic fermentation converts L(-)-malic
acid to L(+)-lactic acid and carbon dioxide. This fermentation
is carried out by lactic acid bacteria which are present
in the pear juice. The malo-lactic fermentation can
occur concurrently with the yeast fermentation but more
often is delayed until the fully fermented perry reaches
15 C, normally in the late spring or early summer of
the year following that in which the perry was made.
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Perry Making Process
process starts with the picking of the pears. These
are left to mature for a period of between 2 days and
1 week depending on the variety of pear used. This period
is much more critical than the equivalent period for
apples in the cider making process. If not left long
enough then very little pear flavour is imparted to
the perry, if left for too long then the fruit begins
to rot from the centre outwards (and thus may go unnoticed)
and will ruin the finished perry. The matured pears
are crushed in a "scratcher" or in more modern
plants they are pulped in a grater mill. As with the
cider making process, the crushed pulp is known as the
pomace or pommy. Unlike the cider making
process, in perry making it is essential that the milled
pomace is allowed to stand for a period before pressing.
This allows the pomace to lose tannins and thus aids
clearing of the perry. The usual period for standing
is overnight up to 24 hours. Next the pulp must be crushed
to extract the juice. This is done in a cider press,
descriptions of which can be found in the cider making guide.
pressed juice is then fermented in one of two different
ways. Traditionally the juice is run into wooden pipes
(barrels which can contain 120 gallons) or smaller wooden
barrels, and the bung is removed. No yeast is added,
the fermentation relies on wild yeasts. The fermentation
will start within 1-2 days and will continue for several
weeks during which time the barrel is topped up with
perry. When fermentation is over, the bung is replaced
and the perry is matured for 5-6 months.
the pear juice is treated with sulphur dioxide to inhibit
natural wild yeasts, and is then fermented with added
pure yeast cultures. The amount of sulphur dioxide which
is required is substantially more than is needed for
cider making. This is because pear juice contains more
acetaldehyde than apple juice. The acetaldehyde neutralises
the effect of sulphur dioxide. At least 100 to 150 ppm
sulphur dioxide is required to be effective. In the
UK the legal limit for sulphur dioxide is 200 ppm and
may well be reduced by subsequent legislation. Always
check your local regulations first! The problems associated
with the need to add high levels of sulphur dioxide
have led some commercial producers to flash-pasteurise
the juice. The advantages of this are that it completely
controls the wild yeast levels. The disadvantages are
that it destroys the bacteria responsible for the subsequent
malo-lactic fermentation. The acidity must be reduced
after the main yeast fermentation by a controlled fermentation
with a suitable strain of lactic acid bacteria.
with commercial cider making, commercial perry makers
often blend new and old perries to ensure consistency
of the product. Because of the difficulties associated
with high tannin pears, commercial perry makers use
low to medium tannin pears which will often be a mixture
of different varieties. The resulting perry, although
requiring less skill to make, is of a lower quality
than that made with high tannin pears.
perry is matured in large storage tanks to allow for
any further precipitation of tannins. Blending is carried
out at this stage. Mutual reactions between the blended
perries can occur and hazes and deposits often form.
These are removed by filtration or centrifugation. The
finished perry is checked for stability by cooling it
to 4 C for 24 hours and observing whether any deposits
or hazes form. If the perry is clear then it is either
sulphited or flash-pasteurised. The perry may then be
sweetened and is artificially carbonated in the bottle
by counter-pressure bottle fillers. The resulting product
may be considered analagous to keg beer. A common example
of this type of perry is the sparkling wine substitute
Pomagne (often sold as Babycham). This bears little
resemblance to real perry so please don't be put off
trying the real thing by this inferior cousin!
perry is served completely flat and may well be cloudy.
It may rarely be found as a naturally-conditioned cask
perry in a similar way to real ale. Naturally sparkling
perry may be made by the traditional champagne method
in a bottle but this is very difficult to do since tannin
deposition interferes with the process of disgorging
the yeast deposit. For this reason it is almost never
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of Pear Juice
pears tend to have a high sugar content than cider apples
and may give specific gravities of up to 1090 or even
more. Unlike cider apples there is a proportion of unfermentable
sugars present, the main contributer being sorbitol.
This can lead to final gravities of between 1010 and
1020. The sorbitol does not contribute towards the alcohol
content of the perry but will leave a residual sweetness
and fuller flavour.
acid composition of perry pears differs substantially
from that of cider apples. Many perry pears contain
appreciable levels of citric acid which may be the predominant
acid in some varieties. Malic acid is also present,
and the levels vary with pear variety, in some pears
it is the dominant acid whilst in others the levels
are less than those of citric acid. Citric acid will
give a sharper taste than malic acid for the equivalent
amount of acid present. It can also lead to microbiological
problems (see below). Pear juice also contains minor
acids such as quinic and shikimic acids.
tannin content of apple juices gives the resulting cider
an overall flavour of bitterness with some astringency.
The tannin content of pear juices is quite different.
Astringent leucoanthocyanins predominate and may be
up to 1% of the total juice. The juice also contains
complex leucoanthocyanins which are colloidal in nature
and which are responsible for the heavy hazes and precipitates
characteristic of perries. The particular component
responsible is probably a polymer of 5,7,3,4-tetrahydroxyflavan-
juices are lower in soluble pectin than apple juices.
The soluble nitrogen content of pear juices is even
lower than that of apple juices. The levels of asparagine
and aspartic acid are lower. Some perry pears may also
contain the unusual amino acid amino-cyclopropane-carboxylic
acid. The final result of all this is that pear juice
does not support yeast growth as well as does apple
juice and fermentation is therefore often sluggish.
Commerical operations routinely add ammonium sulphate
to the juice to ensure rapid fermentations.
compounds contributing to flavour, namely the higher
alcohols and esters, are similar in perries compared
with ciders. However, the range and amount of compounds
seems to be smaller in perries, consequently the aroma
of perry is less intense than that of cider and faults
in the making show up more readily. Some perries may
contain excessive levels of acetaldehyde and ethyl acetate.
This problem can only be overcome by blending.
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Microbiology of Pear Juice
with apple juice this is less well characterised. The
main wild yeasts present are likely to be the same as
those present on apples, namely, Aureobasidium pullulans,
Rhodotorula spp., Torulopsis, Candida,
Metschnikowia, and Kloeckera apiculata.
Fermentation is not only affected by the species of
wild yeast but also the tannin levels of the pear juice.
If the pear is a high tannin variety and has not been
allowed to stand sufficiently long before pressing,
then heavy precipitates of tannin may separate from
the juice taking the natural yeasts with it. This will
result in a long lag period before fermentation can
occur and will greatly increase the chances of infection
of the perry.
low nitrogen content of the juice also affects the microbiological
makeup, favouring undesirable bacteria over wanted yeasts.
This can be overcome by the addition of yeast nutrients.
The recommended amounts being 1 g thiamine hydrochloride
and 8 oz ammonium sulphate per 1,000 gallons for each
10 degrees drop in specific gravity required.
a perry which is well sulphited before the main yeast
fermentation, lactic acid bacteria are kept in check
until the end of the fermentation. The acitivity of
the bacteria then comes into its own, breaking down
malic acid into lactic acid in the malo-lactic fermentation.
The species responsible have not been identified, but
may be presumed to be the same or similar to those responsible
for the malo-lactic fermentation in cider. A problem
arises with perry however. In those pears with a high
citric acid content, the lactic acid bacteria can convert
the citric acid into acetic acid (vinegar) producing
a vinegar taint. Since the lactic acid bacteria are
anaerobic (grow in the absence of oxygen), excluding
air from the perry cannot prevent this occurance. Production
of even small amounts of citric acid will effectively
ruin the perry. Fortunately this is not an invariant
occurance. The bacteria which only attack malic acid
and not citric acid outnumber those which will attack
both. The problem can be completely avoided by flash
pasteurisation of the perry after the main fermentation
is complete, followed by controlled fermentation with
a specific, known strain of lactic acid bacteria.
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in Pear Juice Composition During Fermentation and Maturation
majority of the changes which occur during fermentation
are those which also occur in cider fermentation. The
initial yeast fermentation converts sugars to ethanol
or higher (fusel) alcohol plus carbon dioxide. There
is also an increase in acidity due to the production
of L(-)-malic acid by the yeast. Once the yeast fermentation
is over, the yeast release nitrogenous compounds, pantothenic
acid, and riboflavin into the perry. These compounds
are used by the lactic acid bacteria for the subsequent
malo- lactic fermentation.
maturation phase of the perry includes the malo-lactic
fermentation in which lactic acid bacteria convert malic
acid to lactic acid plus carbon dioxide. An important
differance between cider and perry occurs at this point.
As previously mentioned, perry pears may have substantial
levels of citric acid. This can be converted, by some
strains of lactic acid bacteria, into acetic acid. This
taints the perry with a vinegar taste, effectively ruining
the perry. Fortunately, the predominant bacteria present
in pear juice are those which will not convert citric
acid to acetic acid, but this is always a possibility
to be born in mind.
major differance between perry and cider maturation
is the changes in tannin levels which occur during the
process of perry making. Tannin behaviour is unpredictable,
the juice may clear before fermentation (when the tannin
is thrown out as a gelatinous mass) or it may clear
during fermentation. Tannin may also persist in the
finished perry which may then throw hazes or deposits
at a later stage. Extended milling periods and allowing
the pomace to stand before pressing can substantially
reduce these problems. Oxidation and adsorption of tannin
by the pomace are the main mechanisms which contribute
to the reduction of tannin levels. The oxidation is
partly carried out by pear tissue enzymes and is also
partly non-enzymic. Proteins in the pomace contribute
to tannin reduction by causing a preciptation of the
tannins. In the juice itself, tannin precipitation is
favoured by high tannin levels, by the presence of oxygen,
high acidity and low temperatures. The increase in alcohol
levels as fermentation procedes retards the precipitation.
Addition of sulphur dioxide reduces tannin precipitation
by the formation of sulphonic acid derivatives of the
tannins which increases their solubility. The final
contributing factor is the ripeness of the pear used
to make the perry. Best results are found in pears which
are ripe but not over-mellow. This is the reason why
the milling period of pears is so critical.
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pick your pears. They should be fully ripe (see the
discussion above on the importance of this point) without
being over-ripe. The pears should be left for a period
of 2 days to 1 week depending on variety. This period
is critical for the production of good perry. Please
consult the pear variety guide for the milling periods of common perry
pear varieties. Do not wash or sterilise the pears if
you want the perry to be fermented with wild yeasts.
matured the pears for the critical period, you must
pulp them. This is best achieved by hiring a fruit mill
from a homebrew store. For an alternative approach to
milling fruit, see the short description by Ifor Williams
in his Sacks'N'Socks Cider recipe. Do not seperate the juice and
the pulp. Allow them to stand, covered, for several
hours (preferably overnight) in a cool place. The cooler
the better, since this aids precipitation of tannins
and development of flavour. Once the pulp has stood
for the required period you now need to press it to
extract the juice. This is best achieved in either a
purpose-built cider press, or by hiring a wine-makers fruit press.
These are available for hire from most large homebrew
the juice is separated from the pulp you should check
the pH. The pH will depend on the variety of pear used,
if too many sharp pears are used then the pH will be
too acid. Aim for a pH in the range 3.9 to 4.0. To lower
the pH add malic acid - do not add citric acid, this
will greatly increase the chances of spoilage of the
perry by inappropriate fermentation of the citric acid
to acetic acid. To raise the pH add precipitated chalk.
1 tsp of pectolase per gallon of juice may be added
at this stage to aid in clearing of the perry. This
step is optional and probably not necessary since pears
are low in pectin, and in any case the major problems
with lack of clarity in perries are due to tannins not
check the original gravity. Pears are generally high
in sugar content and it is unlikely that you will need
to add extra sugar. Nevertheless it is wise to check.
Aim for a starting gravity of over 1055. Bear in mind
that many pear juices, especially after a long hot summer
will contain appreciable amounts of non-fermentable
material. The final gravity of the perry may well be
above 1000 even when fully fermented.
the juice in a suitable fermenting vessel. Traditionally
this is a wooden barrel, but a wine fermenter is probably
a better idea since it is easier to sanitise. Put the
juice under an airlock and leave to ferment naturally.
The perry is traditionally fermented at whatever is
the outside temperature at the time. If you wish to
ferment with a specific yeast strain then add 1 crushed
campden tablet per gallon of juice and leave to stand,
covered, for 48 hours. Note that pear juices require
the addition of more campden tablets than do apple juices.
However there are statutary limits to the amount of
sulphur dioxide which can be added to food stuffs -
consult your local regulations on this point. After
standing for 48 hours, pitch with a yeast of your choice.
For a traditional style English perry you should use
an ale yeast. For a pear wine, use a wine yeast such
as a champagne yeast.
the gravity regularly. There is not the same tendancy
with perries to go on fermenting past the desired finishing
gravity as there is with ciders. However, if you wish
to produce a sweet perry then you should add 1 crushed
campden tablet per gallon of juice when your target
final gravity is reached.
the final gravity is attained the perry must be matured.
Rack the perry into glass carboys or other similar container
and place under airlock. Cleanliness is of the utmost
importance at this stage to avoid the introduction of
those strains of lactic acid bacteria which will produce
acetic acid from the natural citric acid of the perry.
Perry is traditionally left to mature in outbuildings
throughout the winter. The fluctuations in temperature
will not hurt it, and in fact exposure to the low temperatures
of an English winter will encourage the deposition of
excess tannins. Don't, however allow the perry to freeze!
Beware of blending perries, this can lead to the formation
of hazes. If you do blend perries they will need an
extended maturation period to clear these hazes. As
the temperature rises to 15 C in the spring or summer
following the year in which the perry was made, the
malo-lactic fermentation will occur. Once this is over,
the perry may be racked and bottled. Traditional perry
is flat, however you may serve it slightly carbonated
in the style of real ale. Beware of trying for too high
a carbonation level, lactic acid bactera grow readily
under high carbon dioxide pressures so you run the risk
of accidental acetification of the perry. Perry carbonated
in the champagne style is very difficult to make, not
only because of the risk of acetification, but also
because tannin deposition interferes with the process
of disgorging the yeast deposit.
the process of perry making requires a little skill
and attention to detail, it is perfectly possible to
produce a perry at home which is the equal of many if
not all of the excellent varieties available at specialist
producers throughout the country.
luck and enjoy your perry!
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Pears edited by L.C. Luckwill and A. Pollard.
Published by the University of Bristol, 1st edition
1963. ISBN unknown. This is a production of The
National Fruit and Cider Institute. The book covers
all aspects of perry making from selecting the
varieties to making the finished product. Highly
readable and enjoyable and strongly recommended
to anyone wishing to produce good perries.
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