the chemistry of cider
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7/24/2019 The Chemistry of Cider
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CBY NC ND
THE CHEMISTRY OF CIDER
COMPOUND INTEREST 2015 - WWW.COMPOUNDCHEM.COM |@COMPOUNDCHEMGraphic: CC BY-NC-ND licence. Photo: Michael Pereckas, CC-BY licence: https://goo.gl/AawdiR
FRUIT ACIDS
AROMA CHEMICALS
TANNINS
SWEETENERS
OH
O
OH
O
HO
OH
O
OH
O
HO
OH
O
OH
OCO
O
O
O
OOH
O
HO
OH
OH
Cl
O
O
HO
HO
Cl
Cl
The main acid present in apples is malic acid.During malo-lactic fermentation, this malic
acid is converted into lactic acid, and carbondioxide gas is also produced. This rounds theavour and reduces the acidity of the cider.
In some cider manufacture, this fermentationis often discouraged. Malic acid can also be
added after fermentation to increase acidity.
Many compounds contribute to the aromaof cider. 2-methyl-4-pentyl-1,3-dioxaneis the most odour active compound, and
is generated when acetaldehyde fromfermentation reacts with 1,3-octanediol, an
alcohol found naturally in apples.
Other contributing compounds include ethyl2-methylbutanoate, which has a fruity aroma,
and 2-phenylethanol, which has a oral aroma.
All of the sugars contained within apples arefermentable, so ciders are naturally dry if thefermentation goes to completion. They can,however, be back-sweetened to produce a
sweeter tasting cider.
Sugar can be used for this, but it can kick-startfermentation again. Some ciders get aroundthis problem by using articial sweeteners,
which are non-fermentable; however, some ofthese, such as saccharine, leave an aftertaste.
MALO-LACTIC FERMENTATION
MALIC ACID
2-METHYL-4-PENTYL-1,3-DIOXANE
ETHYL 2-METHYLBUTANOATE (L) &
2-PHENYLETHANOL (R)
Tannins are naturally occuring polyphenolcompounds, well known for their presence inwine, but also found in cider apples. They add
an astringency and bitterness to the cider.
Many mainstream ciders have relatively lowtannin levels, but more traditional ciders willcontain more. Dierent types of cider apples
will contain dierent levels of tannins.
SUCRALOSE (ARTIFICIAL SWEETENER)
OHO
OH
OH
OH
OH
HO
OH
O
OH
OH
OH
PROCYANIDIN B2
PRESSEDPULPEDPICKING FERMENTING MATURING BOTTLINGApples are picked, then
left to mature for a weekThe apples are crushed
and then pulpedThe apple pulp is pressed
to extract the juiceWild or added yeasts
make alcohol from sugarsCider is matured in barrels
for several monthsCider is bottled andready for drinking