Alcohol fermentation is a biological process where sugars such as glucose and fructose are converted by yeasts into cellular energy and the waste products ethanol and carbon dioxide. Yeasts perform this conversion in the absence of oxygen, making it an anaerobic process. Common organisms used include various species of yeast and bacteria. Sugars, starches, and cellulosic materials can all serve as substrates. The process takes place under controlled temperature, pH, and time conditions to yield ethanol, which has various uses including as a fuel, preservative, solvent, and in alcoholic beverages.

1. ALCOHOL FERMENTATION

2. INDEX:
 INTRODUCTION
 PROCESS
 ORGANISMS USED
 SUBSTRET AND MEDIA
COMPOSITION AND IDEAL
CONDITION
 PRODUCT RECOVERY
 USES
 CONCLUSION

3. alcoholic fermentation, also
referred to as, Ethanol
fermentation, is a biological
process in which sugars such as
glucose, fructose, and sucrose are
converted into cellular energy and
thereby produce ethanol and carbon
dioxide as metabolic waste
products. Because yeasts perform
this conversion in the absence of
oxygen ethanol fermentation is
classified as anaerobic.

4. Conversation Mechanism
C6H12O6
180
C2H5OH + CO2
92 88
100 Kg 51.1 Kg 48.9 Kg
Theoretical Yield : 51.1%

5. Sugar ====> Alcohol + Carbon dioxide gas + Energy
(Glucose) (Ethyl alcohol)

6. Organisms used:
Bacteria:
 Zymomonas mobilis
 Closteridium acetobutylicum
 Klebsiella pneumoniae
Yeast
 Saccharomyces cerevisiae
 Saccharomyces carlsbergenesiae
 Saccharomyces saki
 Saccharomyces oviformis
 Candida utilis
 Mucur sp.

7. FERMANTABLE SUBSTRATE
 Sugary materials
 Starchy material
 Cellulosic materials

8. SUGARY MATERIALS:
Molasses
Suger cane
Sugar beet
Sweet potato
Sulfide waste
Weet sorgum
Whey
glucose
Succrose
Lactose

9. STARCHY MATERIALS
cereals:
wheat,maize,barley,sorgum,corn,rice
Roots:
potato,tropica
Mild products:
wheat flour,corn feed

10. CELLULOSIC MATERIALS
Wood
Paper waste
Agricultural waste

11. Nutrient Raw material
Carbon molasses, starch
Nitrogen corn steep liquor, soybean
meal, pure ammonia or
ammonium salts, urea, nitrate
salts, phosphate salts
Vitamins
and growth
factors
biotin, yeast extract, beef
extract, corn steep liquor,
wheat germ meal
Fermentation media

12. CONDITIONS FOR FERMENTATION
Carbon sources: pure sugar or crude
sugars/molasses (10-18%).
Growth factors: can be provided in the
form of molasses.
pH: 4.8-5.0.
Temperature: 21-26 F. Temp. can be
controlled by heating or cooling of
tanks.

13. CONTN……..
Time: Depends on yeast strain.
Usual time is between 30 to
72hrs.
Yield: 0.4 gallon of ethyl alcohol per
one
gallon of molasses. 90%
carbohydrates can be
converted in to alcohol.

14. FERMENTATION PROCESS CARRY
OUT BY:
 batch fermentation
 Continuous fermentation
continuous fermentation is used
because of several advantages.

15. FERMENTATION
 Inoculums size:
In range of 3% to 10% with an
average about 4%
 Media:
10 -18%. Concentrations
greater than 20% are not employed as
they could be detrimental to yeast.

16. PRODUCT RECOVERY
 Distillation is a separation process for a
mixture of liquids or oils. It relies on
differences in the boiling points of the
component liquids to be separated.
 Alcohol can be obtained by distillation
and column is known as rectified
column.
 Can also be recovered by fractional
distillation. Distillate contains 95.6%
ethyl alcohol and 4.4% water.

18. BY-PRODUCTS
 Three byproducts generated
1.Carbon dioxide- used for production of
dry ice and pure form used for
preparation of soft drinks.
2.Yeast biomass- used for animal fodder
because it contains high protein,
vitamins etc.
3.Distillery effluents- used as a fertilizer
and animal feed.

19. Ethanol Tolerance
Growth Tolerance Production Tolerance
Ethanol level
at which
Growth ceases
6-9% wt/vol
Ethanol level
at which
Ethanol production ceases
15% wt/vol or higher

20. USES:
 Fuels
Some alcohols, mainly ethanol
and methanol can be used as an alcohol
fuel
 Preservative
 Solvents
 Alcohols have applications in industry
and science as reagents or solvents
ethanol can be used as a solvent in
medical drugs, perfumes and vegetable
essences such as vanilla

21.  Alcoholic beverages
 Antifreeze
 Antiseptics
 Ethanol can be used as
an antiseptic to disinfect the skin.

22. CONCLUSION
 Thus alcohol production is an
important fermentation because of
following reasons:
1.Gives ethyl alcohol used for
consumption as well as industrial
purposes.
2.Gives byproducts like carbon dioxide,
yeast biomass, fertilizer etc.
3.Gives effective utilization of agro-
waste eg. Molasses, sulphite waste
liquor etc.