The document discusses various types of beverages, primarily focusing on alcoholic drinks such as wine and beer, along with their production processes. It details the steps involved in wine production, including harvesting, fermentation, aging, and bottling, as well as the brewing process of beer. It also explains the fermentation process for alcohol production, emphasizing the role of yeast and the necessary conditions for optimal yield.

1. Beverages :- Wine,
Beer & Ethanol
HEENA KAUSAR
DEPARTMENT OF MICROBIOLOGY

2. What is beverages
Any potable liquid which is alcoholic and non
alcoholic is known as “beverages” . It is a liquid
intended for human consumption.

3. The large number of beverages may be classified as
shown:

4. Alcoholic beverages
• An alcoholic beverages is a drink that typically contains 30 -
60% ethanol commonly known as alcohol.
• Alcoholic beverages are divided into 3 classes:
 Beer
 Wine
 Spirit (distilled beverages)
• They are legally consumed in most countries around the
world. More than 100 countries have laws regulating their
production , sale and consumption.

6. Fermantation process
• Fermantation is a metabolic process that
converts sugar to acids, gases and /or
alcohol.
• Sugar yeast Alcohol + CO2
• It is a process in which raw or waste
material are convert into economically
important product.

7. Wine
• Wine is an alcoholic beverage
made from the fermentation of
unmodified grape juice.
• The natural chemical
balance of grapes
They ferment without
the addition of sugars,
acids, enzymes or other
nutrients.
Yeast on the outside of grapes

8. • Temperature is the most important factor in
storing wine
– Optimum temperature: 50 to 55°F
– Acceptable temperature: 40 to 65°F
Grape Varieties
Wine is usually made from one or more varieties of
the European species.

9. Pinot Noir
Chardonnay

10. Merlot
Vitis vinifera

11. Steps of wine production
1. Harvesting
2. Stemming/Crushing
3. Fermentation
4. Draining
5. Pressing
6. Mixing
7. Clarification
8. Aging
9. Bottleing

12. Harvesting
• Descision of harvest
informed by level of
sugar and acid.
• Grapes are picked up
by hand or
mechanically.

13. Stemming/Crushing
• Stemming is the separation of the stems
and grapes (which are sends to the press)
Crushing: A horizontal press squeezes the
broken grapes, separating the fresh juice
(must) from the skins (marc)
• After crushing starts the fermentation
process.

14. Fermentation
• Sugar and acids that
naturally react with
wild yeasts
• Vineyard adding their
own yeasts
• Fermentation can take
from 10 to 30 days to
convert natural sugar
to alcohol.
Wine fermentation tanks

15. Draining
• Liquid wine is
drained from the vat
without being
pressed and go into
barrels (free-run
wine). The
remaining pulp
retains about 20% of
the wine.

16. Pressing
• The remaining pulp,
after draining, is
pressed to squeeze
out the press wine.
The press wine tends
to be dark, harsh and
is mixed with free-
run wine to produce
something decent.
Grape pomace after pressing

17. Newer style equipment for pressing
grapes

18. Mixing
• The free-run wine and press
wine, always from the same
source, are mixed together in
appropriate ratios to obtain
the desired balance.

19. • Clarification
• Clarification is the step of stabilisation of fermentation.
• During clarification all remaining solids are removed from the
fermented liquid.
• Clarification done in numerous ways:
 Running the liquid through coarse and fine filters
 Siphoning the liquid off the top of the fermenting vats after the
solids have settled to the bottom

20. Aging
• The final stage in vinification is aging the wine. At this
point, the clarified wine is transferred into either wooden
barrels or metal vats in which the wine is allowed to
further mature and develop flavors. If a winemaker
chooses to age the wine in wooden casks, he will be
allowing the wine to pick up flavors from the wood,
adding greater depth to its flavors. While this can add
body to some wines, keep in mind that the “woody”
flavor isn’t suited to all types of wine, hence the use of
metal vats.

21. Aging of wine in
barrels

22. Bottleing
• The final step of wine
production.
• A dose of sulfite is added
to help preserve the wine
and prevent unwanted
fermentation in the bottle.
• The wine bottles then are
traditionally sealed with a
cork, but now use
synthetic corks and
screwcaps, which are less
subject to cork taint, are
becoming increasingly
popular.

23. Different Kinds of Wine
• Red or white wine
• Rosé wine
• Table wine
• Sparkling wines
• Dessert wine
• Fortified wine
• Cooking wine

24. Red wine
• Red wine is made from
red (or black) grapes
• But its red color is
bestowed by a process
called maceration
– whereby the skin is left in
contact with the juice
during fermentation

25. White wine
• White wine can be made
from any color of grape.
• As the skin is separated
from the juice during
fermentation.

26. Rose wine
• A white wine made from
a very dark grape may
appear pink, "rosé" or
"blush".

27. Sparkling Wines
• Sparkling wines such
as champagne,
contained carbon
dioxide which is
produced naturally
from fermentation.

28. Dessert wine
• Dessert wines range
from slightly sweet
(with less than 50 g/L
of sugar) to
incredibly sweet
wines (with over 400
g/L of sugar).

29. Fortified Wine
• Fortified wines are often sweeter, and generally
more alcoholic wines.

30. Beer
• Beer is an alcoholic
beverage usually
made from malted .
• Cereal grain (as
barley), flavored with
hops, and brewed
by slow
Fermentation.

31. What is beer made of?
• Malted Barley
• Hops
• Yeast
• Water
Not required, but frequently found ingredient
– Starch adjuncts
• Corn and rice starches

32. Making Beer:
a three step process
• Malting
• Brewing
• Fermentation

33. Malting
• In the preparation of malt , barley grains are
soaked at 10 to 15.6 C , and germinated at 16
to 21 C for 5 to 7 days.
• Most of the sprout or germs are removed, and
the malt remains.

34. Brewing process
1. Mashing
2. Fermenting
3. Conditioning
4. Filtering
5. Packaging

35. Mashing
• Main ingredients such as water, malted barley
and hops are put in a kettle and mix at 38 to 50 C.
• The mash is then boiled with hops in order to
obtain wort.
• Hot wort is cooled down to fermenting
temperature and then fermented using beer yeast.

36. Fermentation
• Fermentation process is takes place
in closed fermentation tanks.
• Determined fermentation time and
temperature must be observed.
• During fermentation, the highest
amount of alcohol and carbon
dioxide is produced. Following the
fermentation, fresh beer is racked in
conditioning.
Fig : - Beer Fermentation

37. Conditioning
• With fermentation complete, the
beer is removed from the yeast
and pumped to a conditioning or
bright tank.
• Where it is stored at near freezing
temperatures that cause most of
the remaining yeast to drop out of
suspension.
• Once the beer is clear it is ready to
filter and package.

38. Filtering and packaging
Conditioned beer is filtered using a
kieselguhr filter. The filtered,
purified beer is stored in storage
tanks.
Filtering
When beer is purified and
filtered it is packaged in clean
glass bottles and kegs.
Packaging

39. Alcoholic fermentation (ethanol)
• Ethanol fermentation also called alcoholic
fermentation, is a biological process which convert
sugar such as glucose, fructose and sucrose into
cellular energy, producing ethanol and CO2.
yeast
Sugar Alcohol + CO2
• Because yeasts perform this conversion in the
absence of oxygen.
• Alcoholic fermentation is considered an anaerobic
process.

40. • Usually the strain of yeast, Sacchromyces cerevisiae
are employed for commercial production of ethyl
alcohol.
• Generally, strains of S. cerevisiae are selected when
starchy material, as well as saccharide material like
mollasses are use as raw material.

41. •One glucose molecule breaks down
into two pyruvates.
•The energy from this exothermic
reaction is used to bind inorganic
phosphates to ADP and convert
NAD+ to NADH.
•The two pyruvates are then
broken down into two
acetaldehydes and give off two CO2
as a waste product .
•The two acetaldehydes are then
converted to two ethanol by using
the H- ions from NADH

42. Raw materials
• A variety of corbohydrates available as waste product
of agricultural industries are used for preparation of
fermentation medium.
• On the basis of their chemical nature they may be
group as-
 Saccharide material – molasses , whey, fruit juices
 Starchy material – potato starch, corn starch wheat
flour.
 Cellulosic material – sulphite waste material and
liquor

43. Fermentation condition
• Carbon source - Sugar concentration in the range of
10 to 18 % is found satisfactory.
 Ex- Cane molasses contains sucrose as a carbon
source.
• Nitrogen source – Ammonium sulphate (0.15 gms /
2.5 gallons of molasses)is generally used.

44. • pH – pH of the fermentation medium is adjusted to
4.8 – 5 . The higher value of pH increase the chance
of contaimination, whereas the lower pH values
inhibit the yield of ethyl alcohol.
• Temperature – Usually, the temp. range of 70-80 ͦ F
is preferred.
• Time – Fermentation starts within a few hours after
the addition of yeast, the process complete after 30-72
hrs in this stage it contains 6-8% of ethyl alcohol.

45. • Yield – On an average of 0.4 gallons of ethyl
alcohol is obtained from one gallon of molasses.
About 90% of carbohydrates converted to alcohol.

46. • Recovery – The fermented liquid is allowed to
settle for a few hours and then distilled in
analyser and rectifier columns to obtain
rectifier spirit ethyl alcohol.
• The highest concentration that can be secured
by fractional distillation is the constant boilling
mixture which contains 95.6% ethyl alcohol
and remaining 4.4% is water.

47. References
• Industrial microbiology by A. H. patel Pg. no. 146-148.
• Industrial microbiology by L. E. Casida , JR , chapter 18
anaerobic fermentation pg. no. 299- 303.
• Food microbiology 4th edition by W. C. Frazier and D. C.
Westhoff chapter 22 , food fermentations pg. no. 339-
341.

48. Thank you