Food Chemistry

(Sean Pound) #1

930 20 Alcoholic Beverages


Table 20.27.Alcohol consumption with respect to the
type of drink in l per inhabitant in 2003


Country Spirits Wine Beer Total


Luxembourg 1. 66. 74. 312. 6
Hungary 3. 53. 94. 011. 4
Czech Rep. 3. 81. 06. 211. 0
Ireland 2. 02. 76. 110. 8
Germanya 1. 02. 65. 610. 1
Spain 2. 43. 24. 410. 0
UK 1. 82. 25. 69. 6
Denmark 1. 13. 54. 99. 5
France 2. 44. 92. 09. 3
Austria 1. 43. 24. 79. 3
Switzerland 1. 64. 13. 39. 0
Slowakia 3. 51. 23. 88. 5
Lettland 6. 10. 51. 58. 1
Greece 1. 63. 42. 77. 7
Sweden 0. 91. 72. 34. 9
aIn 2004.


and oligosaccharides (sucrose, lactose, raffinose,
gentianose, melecitose, etc.) or polysaccharides.
The main raw materials are:



  • alcohol-containing liquids (wine, beer, fruit
    wines, fermented milk);

  • sugar-containing sources, such as sugar cane
    and beet, molasses, fruit and fruit products,
    fruit pomace, whey, palm extract and sugar-
    rich parts of tropical plants;

  • starch- and inulin-containing raw materials
    (fruit, cereal, potato, topinambur, sweet
    potato, cassava, tapioca or chicory).


Saccharification of the starch-containing material
is achieved with malt (green malt or kiln-dried
malt), or by microbial amylases e. g., from the
molds Aspergillus niger and A. oryzae. Fermen-
tation is achieved withSaccharomyces cerevisiae,
which converts sucrose and hexoses (glucose,
galactose, mannose, fructose). Other substrates
can be fermented, e. g., with Saccharomyces
uvarum (raffinose), Kluyveromyces fragilis
(lactose), andKluyveromyces marxianus(inulin).
Distillation is performed in various ways, depend-
ing on the source and desired end-product. For the
distillation of rum, arrack, fruit brandies and cer-
eals, and brandy from wine, the apparatus is of-
ten a relatively simple still, used in such a way
as to obtain a distillate which contains several


other products of fermentation besides ethanol, or
which contains the aroma substances of the start-
ing raw material. These aroma substances are al-
cohols, esters, aldehydes, acids, essential oils and
hydrogen cyanide. Repeated distillation is needed
to obtain an alcohol-enriched distillate. In the pro-
duction of pure or absolute alcohol the aim is the
opposite: the final product being free from mate-
rials other than ethanol.

20.3.2.2 Alcohol Production

Alcohol used for drinks is made primarily
from potatoes, cereals and molasses. Distiller’s
yeast, especially the top fermenting culture
(cf. 20.3.2.1), is used for fermentation. Since
the fermentation proceeds in an unsterilized
mash and at elevated temperatures and since the
growth of yeast occurs in mash acidified with
lactic or sulfuric acid (pH 2.5–5.5), the yeast
must be highly fermentative, tolerant of elevated
temperatures (≤ 43 ◦C) and resistant to acids and
alcohol. In addition to saccharification by malt
which contains mainlyβ-amylase, high-activity
microbialα-amylases are also used. Molasses
does not require saccharification. The sacchari-
fied mash is cooled to 30◦C and then inoculated
with a yeast starter which has been cultured on
a sulfuric or lactic acid medium of the mash
or directly with distiller’s yeast. After 48 h of
fermentation, the ethanol present at 6–10% by
volume in the mash is distilled off along with
the other volatile constituents. This step and the
following rectification of the crude alcohol are
achieved by continuous processes.
To facilitate the removal of the fusel oils, the
crude alcohol is diluted to 15% by volume prior
to rectification. The head product obtained from
the rectification column consists nearly of pure
ethanol (96.6% by volume) which is used for
production of alcohol-fortified beverages. Large
amounts of acetaldehyde, methanol and low
boiling esters are present in the first runnings
of the distillate, while the last runnings contain
primarily fusel oil, other high alcohols, furfural
and esters. These runnings combined with other
intermediate fractions provide technical alcohol.
The fusel oil, obtained in amounts of 0.1–0.5l
per 100 l alcohol, is used for technical purposes,
while the distillation residue (the wash or stil-
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