Food biotechnology- alcoholic beverages

1. FOOD BIOTECHNOLOGY
ALCOHOLIC BEVERAGES
SUMBITED BY
R.YASOTHA

2. INTRODUTION
 All alcoholic beverages involve the action of fungi.
 Most involve the genus Saccharomyces. These yeasts covert six carbon
sugars such as glucose to ethanol and carbon dioxide and live under
anaerobic conditions. Yeasts can tolerate fairly high concentrations of
alcohol (up to about 14-18%) in the medium.
 Alcoholic beverages are known from virtually all cultures. These beverages
are major social problems, but also sources of nutrition.
 Many plants have been used to prepare alcoholic beverages. Mead is made
from fermented honey.

3.  Plants often store nutrition as starch. Yeasts cannot use starch. The starch
is broken down by enzymes in the plant into sugars. The sugars are then
converted by the yeasts into ethanol and carbon dioxide.
 Alcohol is a lipid and moves freely across membranes in the stomach.
 Alcohol is broken down in humans, but also affects the neurons and is a
non-selective central nervous system depressant.

4. YEAST
 In browing, alcoholic fermentation comprises the conversion of sugar into
carbondioxide and ethyl alcohol. This process is carried out by yeast enzymes.
 In browning we use the sugar fungi form of yeast. These cells gain energy from
breaking down the sugar.
 The product, CO2 bubbles through the liquid and dissipates into air. Alcohol
remains in the yeast cells die, when the level of alcohol exceeds beyond tolerance.
Brewers yeast tolerates about 5% alcoholic beyond this level the yeast can not
continue fermentation.
 The overall process of fermentation aims to convert glucose sugar (C6H2O6) into
alcohol(CH3CH2OH)and carbondioxide.

5. The reaction with in yeast make this happen:

6. BREWER’S YEAST
 Brewer’s yeast is dried, pulverized cells of saccharomyces cervisia, a
type of yeast that reproduce by budding.
 They are hundreds of varieties and straing of this yeast in the past,
there were two types of beer yeast;
 ale yeast : [ the “top fermenting type, saccharomyces cerviside ]and
large yeast: [the “bottom – fermenting “type, saccharomyces
uvarum,tormerly known as saccharomyces carlsbergensis].

7. ALE YEAST:
 Ale yeast strains are best used at temperatures between 10 and 25*c though some
strains will not actively ferment below 12*c ale yeast is generally regarded as
top – fermenting yeast since it rises to the surface during fermentation,
creating a very thick, rich yeast head.
 That why the lerm “top fermenting” is assosiated with ale yeast.
 Ale yeast produce beer high in esters.

8. LARGE YEAST;
 Large yeast strains are best used at temperature between 7and 15*C large yeast –
grow less rapidly than ale yeasts, and with less surface form they tend to settle to
the bottom of the fermenter at the and of fermentation.
 This is why they are often refferred as “bottom” fermenting yeasts.
 The final flour of beer will however, depend greatly on the strain of yeast and the
temperatures at which it is fermented.
.

9. YEAST LIFE CYCLE;
 Yeast is activated from dormancy as soon as it is added [pitched] to the wort.
yeast growth follows four phases:
The lag phase
Growth phase
Fermentation phase
Sedimentation phase

10. LAG PHASE:
 Reproduction is the priority in pitching, and the yeast will not show any other
activity untill food reserves are built up this stage is marked by a drop in PH due to
untilyzation of phosphate and reduction in oxygen.
 Glycogen,an intracelluler carbohydrate reserve. Is a prime energy sources for cell
activity since wort sugars are not assimilated early in the lag phase.low geycogen
levels produce abnormal levels of vicinal dixetones [ especialy diacetyl]and may
result in longer fermentation.

11. Growth phase
 The growth phase aften refered to as the respiration phase,follows the log phase
once sufficient reserves are built up within the yeast.
 In this phase the yeast cells use oxygen in worth to oxidize a variety of acid
compounds resulting in a significant drop of PH. In this connection, some yeast
strains will result in a much greater fall in PH than others with in the same
fermenting wort.

12. FERMENTATION PHASE:
 The fermentation phase quickly follows the growth phase when the oxygen supply
was been depleted.
 Fermentation is an anaerobic process. In fact any oxygen remaining in the wort is
stripped out of the solution by carbondioxide bubbles produced by yeast.
 This phase is characterized by the reduction of wort gravity and the production of
carbondioxide. ethanol and beer flavours.
 Most beer yeast will remain in suspension for 3or7days, after which flocculation
and sedimentation will commence.

13. SEDIMENTATION PHASE:
 The sedimentation phase is when the yeast flocclates and settles to the bottom of
the fermenter.
 The yeast produces a substance called glycogen, wich will preserve its. Life as it
prepares it self for dormancy.
 Glycogen is necessary for cell maintance during dormancy and is an energy source
during the lag phase.

14. Products of Alcoholic Fermentation

15. WINE FLOW CHARTS
Ripe grapes
Washing, removal of stem and crushing
Filling jar up to ¾
Addition of sugar
Adjustment of pH [0.6-0.8]
Addition of preservative [1.5g/10kg of fruit]
Addition of wine yeast [S.ellopodevs]
Fermentation [For 2 day]
Filtration

16. Fermentation[For 10 days]
Packing [siphoning of clear liquid]
Fining and filtration [bentonies]
Aging 6-8 [months]
Bottling
Crocon corking
Pasteurization[85*c for 20min]
Cooling
Storage

17. Wine fermentation tanks

18. BEER FLOW CHART
Barley grains
Washing
Soaking
Malting [involves soaking, steeping, germination, drying and crushing.]
Mashing [mixing of ground malt with water and heated at 70*C
Worting [inactivation of enzyme] and boiling with hops S.cervisiae S.carlbergenos
fermentation
Maturing
Packaging

19. Barley fields in California
and Germany

20. BRANDY FLOW CHART
Cashew apple fruits
Plucking and removing nuts
Transportation
Washing and weighing
Fruit-mill
Juice extraction
Sulphitation
Inoculation
Fermentation

21. Distillation
Adjusting the strength to 60%
Aging in wooden barrels
Dilution to 43% alcohol
Bottling
Labelling

22. VODKA FLOW CHART

24. TANK YOU