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Describes about the fermentative production of alcohol,beer,wine and other distilled bevarages such as brandy,whisky,etc....

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  1. 1. Presented by MARIYA RAJU
  2. 2. ETHANOL Properties  Also referred to as ethyl alcohol  It’s chemical formula: CH3CH2OH  Molecular Weight: 46.07grams  Ethanol is an alcohol ( has a hydroxyl group, an -OH bonded to a carbon atom).  Is a clear, colorless liquid with slight odor  In dilute aqueous solution, has relatively sweet flavor, but when concentrated, it has a burning taste
  3. 3. Properties (continued)  Melting point of -114.1 degrees Celsius  Boiling point of 78.5 degrees Celsius  Density of 0.798g/mL at 20 degrees Celsius  Stable but highly flammable  Incompatible with acids, alkali metals, moisture, peroxides, etc.
  4. 4. Uses of Ethanol  Used as antifreeze in automobile radiators  Used to make several types of alcohol (such as whisky and brandy)  Used to burn in automobile engines like gasoline
  5. 5. Gasohol • A fuel consisting of a blend of ethyl alcohol and unleaded gasoline,especia lly a blend of 10 percent ethanol and 90percent gasoline • Used as an automobile fuel • In testing, it has been shown to reduce emissions of carbon monoxide, particular, and nitrous oxide over conventional fuels
  6. 6. The Alcohol Part  Made since ancient times by fermentation of sugars (beverage ethanol is still made by this process: simple sugars are the raw material, and Zymase an enzyme from yeast, changes the simple sugars into ethanol and carbon dioxide by this rxn:)  C6H12O6 ---> 2 CH3CH2OH + 2 CO2  Reaction is complex because impure cultures of yeast produce other substances and various other organic acids (in the production of beverages, such as whisky and brandy, the impurities bring about flavor)
  7. 7. YEAST • The role of yeasts in alcoholic fermentation was revealed by Pasteur’s work on wines • These microscopic fungi naturally transform sugar from the grapes into alcohol • Saccharomyces cerevisae, the species of yeast used by winemakers • Besides its direct action on transforming the sugar present in grapes into alcohol yeasts also contribute towards revealing aromas
  8. 8. Cont…. Two types of brewer's yeasts • There are two main types of brewer’s yeast: • The bottom-fermenting yeast, Saccharomyces uvarum (lager fermentation) • The top-fermenting yeast, Saccharomyces cerevisiae (ale fermentation) • Their action is identical: they absorb the sugars present in the fermentation tank (melibiose for lager fermentation, fructose for ale fermentation) to turn them into alcohol.
  9. 9. • Saccharomyces uvarum
  10. 10. Saccharomyces cerevisiae
  11. 11. Selection of Yeast • Rapid Fermentation • Yeast stress tolerance • Flocculation • Attenuation • Flavour component • Yeast Degeneration
  12. 12. ALCOHOLIC FERMENTATION • Alcohol fermentation, also known as ethanol fermentationis the anaerobic pathway carried out by yeasts in which simple sugars are converted to ethanol and carbon dioxide • Yeasts typically function under aerobic conditions, or in the presence of oxygen, but are also capable of functioning under anaerobic conditions, or in the absence of oxygen • When no oxygen is readily available, alcohol fermentation occurs in the cytosol of yeast cells
  14. 14. Ethanol Production process
  15. 15. Cont…. • Steps in alcoholic fermentation • Preparation of Nutrient solution • Fermentation • Distillation of ethanol
  16. 16. Preparation of Nutrient solution • Starch containing roots,tubers,grains • Molasses or juice from Sugar cane,sugar beet • Wood or waste products from processed wood
  17. 17. Fermentation Continuous fermentation
  18. 18. Distillation
  19. 19.
  20. 20. Raw Materials
  21. 21. Malt • Malt is one of the main ingredients and is obtained from barley • which is subjected to a process of germination under controlled conditions • This operation (called malting) causes, towards the end of the production process, the development of carbohydrates and nitrogenous substances by the enzymes formed during the germination process • Varying conditions during the malting process (temperature and humidity) allows different types of malt to be obtained, giving different colours and flavours to the beer
  22. 22. Barley
  23. 23. Other unmalted cereals • Of the unmalted cereals normally used, corn is very common • The oils are extracted, then it is milled and called grits • Barley, rice or wheat may also be used • • These cereals are used to reduce the percentage of proteins in the wort • Unmalted cereals give the beer a lighter colour and specific characteristics according to the type of cereal chosen
  24. 24. Hops (humulus lupulos) • The hop (humulus lupulos) is an aromatic plant • Gives beer its flavour and bitterness • It contributes to the formation of a good froth and protects the beer against contamination by microorganisms • Today, extracts from this plant are used industrially, obtained in such a way as to preserve its qualities • Hop varieties are classified in terms of bitterness and flavour, which vary according to the amount of resin and essential oils they contain
  25. 25. Hops (humulus lupulos
  26. 26. Production Process
  27. 27. Preparing the Wort The first phase in the process of beer production is the preparation of the wort. This process has four stages:
  28. 28. I) Milling/Malting • In order for the malt components to be rapidly extracted and converted, the malt is milled to obtain coarse flour • The other unmalted cereals are also milled to varying degrees
  29. 29. II) Mashing: • The flour from the cereals (malt and other unmalted cereals) is mixed with water • Subjected to certain processes to obtain a wort of a suitable composition for the kind of beer being produced (varying times, temperatures and PH) • These conditions encourage the development of complex starch molecules and proteins in other simpler ones by means of enzymes formed during the production of the malt • Mashing lasts 2 to 4 hours and finishes with a temperature of approximately 75 ºC
  30. 30. III)Filtration of the wort • After mashing, the whole volume is filtered in order to separate the spent grains • (which is an excellent animal feed) from the wort itself • This is done by passing water through the mash at the right temperature in a filter press or lauter tun, which lasts around 2-3 hours, conducted at a temperature of 75-80 ºC
  31. 31. IV)Boiling the wort  The diluted and filtered wort is boiled for around 2 hours  Hops are added at this stage  The purpose of boiling is to:  Transform and make soluble the bitter substances in the hops;  Eliminate undesirable volatile substances;  Sterilise the wort;  Provoke the precipitation of proteins of high molecular weight;  Establish the final concentration of wort
  32. 32. Cont…….. • After boiling, it is necessary to separate the precipitated protein and the insoluble hop components from the hot wort • Separation may be carried out in a decanter using gravity or with centripetal force in a "whirlpool“ • Before the hopped wort goes into the fermentation tanks, it is cooled to a temperature of around 9 ºC and aired in sterile conditions
  33. 33. Fermentation During fermentation, the wort sugars are converted by the transformation of yeast into alcohol and carbon dioxide  Fermentation begins when yeast of a culture selected for the type of beer being produced is added to the cooled oxygen-saturated wort Fermentation takes place at controlled temperatures and lasts around 7 days At first it is quite violent, then slows down gradually until the yeast is deposited on the bottom of the tank
  34. 34. Tower Fermenter
  35. 35. Maturation • The phase after fermentation • The period in which the beer is allowed to rest at suitable temperatures in order for the undesirable volatile components, which might affect the final «bouquet» of the beer, to be released
  36. 36. Maturation
  37. 37. Stabilisation • This consists of letting the beer stabilise at temperatures of between 0ºC and - 2ºC, to permit colloidal stabilisation
  38. 38. Clarification of the Beer • Clarification is the operation that gives the beer its clear limpid quality • Eliminating the last remaining traces of clouding still in suspension • It consists of pumping the liquid through a suitable filter • The filtered beer is then stored in tanks, now ready to be bottled.
  39. 39. Bottling • The final stage of the beer production process is transferring the beer into different kinds of containers (bottles, barrels, cans etc) • Before or after bottling, the beer needs to be biologically stabilised • This operation may be carried out cold (sterilising filtration) or hot (using pasteurisation, which may be done either immediately before - flash pasteurization - or after the drink is introduced into its container - tunnel pasteurisation)
  40. 40. Beer Bottling
  42. 42. Wine Production : Main Steps 1.Viticulture 2.Harvesting 3.Stemming/Crushing 4.Fermentation 5.Draining 6.Pressing 7.Mixing 8.Clarification 9.Aging 10.Bottleing
  43. 43. Viticulture Factors which influence grape’s flavor: •climate of the vineyard’s region •drainage around the vines •humidity of the region •sun exposure •soil quality
  44. 44. Harvesting •Grappes are picked up by hand or mechanically •Descision of harvest informed by level of sugar and acid weather forecasts
  45. 45. 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
  46. 46. 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
  47. 47. 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 Pressing • The remaing pulp, after draining, is pressed to squeeze out the press wine • The press wine tends to be dark, harsh and unpalatable, and is mixed with free-run wine to produce something decent
  48. 48. Mixing The free-run wine and press wine, always from the same source, are mixed together in appropriate ratios to obtain the desired balance. 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: •Fining, a process that calls for the addition of substances that cause the solids in the liquid to adhere to one another and sink to the bottom of the vat •Running the liquid through coarse and fine filters
  49. 49. 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
  50. 50. 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, although alternative wine clossure such as synthetic corks and screwcaps
  51. 51. Types of Wine • Red Wine • White Wine • Dry Wine • Sweet Wine • Fortified Wine
  52. 52. Brandy • The name brandy comes from the Dutch word brandewijn, meaning "burnt wine." • The name is apt as most brandies are made by applying heat, originally from open flames, to wine • The heat drives out and concentrates the alcohol naturally present in the wine • Because alcohol has a lower boiling point (172°F, 78°C) than water (212'F, 100°C), it can be boiled off while the water portion of the wine remains in the still
  53. 53. Cont… • Heating a liquid to separate components with different boiling points is called heat distillation • While brandies are usually made from wine or other fermented fruit juices • it can be distilled from any liquid that contains sugar • All that is required is that the liquid be allowed to ferment
  54. 54. Raw Materials • The raw materials used in brandy production are liquids that contain any form of sugar. • Grapes, apples, blackberries, sugar cane, , rice, wheat, corn, potatoes, and rye are all commonly fermented and distilled • Heat, used to warm the stills, is the other main raw material required for brandy production
  55. 55. Raw materials
  56. 56. The Manufacturing Process 1. The first step in making fine brandies is to allow the fruit juice (typically grape) to ferment. 2. This usually means placing the juice, or must as it is known in the distilling trade, in a large vat at 68-77°F (20-25°C) and leaving it for five days 3. During this period, natural yeast present in the distillery environment will ferment the sugar present in the must into alcohol and carbon dioxide 4. The white wine grapes used for most fine brandy usually ferment to an alcohol content of around 10%
  57. 57. Cont…. • Fine brandies are always made in small batches using pot stills • A pot still is simply a large pot, usually made out of copper, with a bulbous top • The pot still is heated to the point where the fermented liquid reaches the boiling point of alcohol • The alcohol vapors, which contain a large amount of water vapor, rise in the still into the bulbous top
  58. 58. Pot stills
  59. 59. Cont…. • The vapors are funneled from the pot still through a bent pipe to a condenser where the vapors are chilled, condensing the vapors back to a liquid with a much higher alcohol content • The purpose of the bulbous top and bent pipe is to allow undesirable compounds to condense and fall back into the stil • Thus, these elements do not end up in the final product • Most fine brandy makers double distill their brandy, meaning they concentrate the alcohol twice
  60. 60. Cont…. • It takes about 9 gal (34 1) of wine to make I gal (3.8 1) of brandy • After the first distillation, which takes about eight hours, 3,500 gal (13,249 1) of wine have been converted to about 1,200 gal (4,542 1) of concentrated liquid (not yet brandy) with an alcohol content of 26-32% • The brandy is not yet ready to drink after the second distillation. • It must first be placed in oak casks and allowed to age, an important step in the production process • Most brandy consumed today, even fine brandy, is less than six years old • However, some fine brandies are more than 50 years old • As the brandy ages, it absorbs flavors from the oak while its own structure softens, becoming less astringent • Through evaporation, brandy will lose about 1% of its alcohol per year for the first 50 years or so it is "on oak."
  61. 61. Byproducts/Waste • The waste products from brandy production include the solids from the wine production and the liquids left over from the still • The solids from brandy production can be used for animal feed or be composted • The liquid wastes are usually allowed to evaporate in shallow ponds • This allows the residual alcohol in the waste to go into the atmosphere, but the United States Environmental Protection Agency does not consider this to be a major pollutant source.
  63. 63. Main ingredients: 1. Base Ingredient — A sugary or starchy base ingredient, whose sugars can be fermented, as in the process of making beer or wine 2. Yeast 3. Water 4. Flavorings — Some spirits owe their character to the addition of distinctive flavoring These can include herbs, spices, honey, fruits, and vegetables
  64. 64. Manufacturing Steps • Mash preparation  The grain or vegetables are loaded into an automatic mash tub. Much like a washing machine, the tub is fitted with agitators that break down the grain as the tub rotates  A ground malt meal is added to promote the conversion of starches to sugar.
  65. 65. Sterilization and inoculation  Preventing the growth of bacteria is very important in the manufacture of distilled spirits  First, the mash is sterilized by heating it to the boiling point  Then, it is injected with lactic-acid bacteria to raise the acidity level  needed for fermentation  When the desired acidity level is reached, the mash is inoculated once again
  66. 66. Fermentation • The mash is poured into large stainless-steel vats • Yeast is added and the vats are closed. Over the next two to four days, enzymes in the yeast convert the sugars in the mash to ethyl alcohol
  67. 67. Distillation and rectification  The liquid ethyl alcohol is pumped to stills, stainless steel columns made up of vaporization chambers stacked on top of each other  The alcohol is continuously cycled up and down, and heated with steam, until the vapors are released and condensed  This process also removes impurities  The vapors rise into the upper chambers (still heads) where they are concentrated  The extracted materials flow into the lower chambers and are discarded. Some of the grain residue may be sold as livestock feed
  68. 68. Water added • The concentrated vapors, or fine spirits, contain 95-100% alcohol • This translates to 190 proof • In order to make it drinkable, water is added to the spirits to decrease the alcohol percentage to 40, and the proof to 80
  69. 69. Bottling • Alcoholic beverages are stored in glass bottles because glass is non-reactive • Other receptacles, such as plastic, would cause a chemical change in the beverage • The bottling procedure is highly mechanized as the bottles are cleaned, filled, capped, sealed, labeled, and loaded into cartons • This can be done at rates as high as 400 bottles per minute
  71. 71. WHISKY • Whisky is a spirit produced from fermented grain and aged in wood • Some claim that whiskey was invented in Ireland as long as 1,000 years ago and carried to Scotland by monks
  72. 72. Raw Materials • Whiskey is made from water, yeast, and grain • The water used is often considered the most important factor in making good whiskey • It should be clean, clear, and free
  73. 73. The Manufacturing Process Preparing the grain  The grain is inspected and cleaned to remove all dust and other foreign particles  2 All grains except barley are first ground into meal in a gristmill  The meal is then mixed with water and cooked to break down the cellulose walls that contain starch granules  This can be done in a closed pressure cooker at temperatures of up to 311°F (155°C) or more slowly in an open cooker at 212°F (100°C)
  74. 74. Cont….  Instead of being cooked, barley is malted  The first step in malting barley consists of soaking it in water until it is thoroughly saturated  It is then spread out and sprinkled with water for about three weeks, at which time it begins to sprout • During this germination the enzyme amylase is produced, which converts the starch in the barley into sugars • The sprouting is halted by drying the barley and heating it with hot air from a kiln
  75. 75. Mashing  Mashing consists of mixing cooked grain with malted barley and warm water  The amylase in the malted barley converts the starch in the other grains into sugars  After several hours the mixture is converted into a turbid, sugar-rich liquid known as mash
  76. 76. Fermenting  The mash or wort is transferred to a fermentation vessel, usually closed in Scotland and open in the United States  These vessels may be made of wood or stainless steel  Yeast is added to begin fermentation, in which the single-celled yeast organisms convert the sugars in the mash or wort to alcohol  The yeast may be added in the form of new, never-used yeast cells  The sour mash method is more often used because it is effective at room temperature and its low pH (high acidity) promotes yeast growth and inhibits the growth of bacteria 
  77. 77. Cont…  The sweet mash method is more difficult to control, and it must be used at temperatures above 80°F (27°C) to speed up the fermentation and to avoid bacterial contamination  After three or four days, the end product of fermentation is a liquid containing about 10% alcohol known as distiller's beer in the United States or wash in Scotland
  78. 78. Distilling  Scottish whiskymakers often distill their wash in traditional copper pot stills  The wash is heated so that most of the alcohol (which boils at 172°F [78°C]) is transformed into vapor but most of the water (which boils at 212°F [100°C]) is not  This vapor is transferred back into liquid alcohol in a water-cooled condenser and collected  Most modern distilleries use a continuous still
  79. 79. Cont.. The temperature of distillation and other factors determine the proportions of water, alcohol, and other substances (called congeners) in the final product  If it contains more than 95% alcohol it will have no flavor because it has no congeners  This product is known as grain neutral spirit and is often used to add alcohol without adding taste during blending  If the final product has too many congeners of the wrong kind it will taste bad  Distillers remove bad-tasting congeners (usually aldehydes, acids, esters, and higher alcohols) in various ways  Some congeners boil at a lower temperature than alcohol and can be boiled off
  80. 80.  Some congeners boil at a lower temperature than alcohol and can be boiled off  Some are lighter than alcohol and will float on top, where they can be poured off
  81. 81. Aging  Water is added to the high wine to reduce its alcohol content to about 50% or 60% for American whiskeys and about 65% or higher for Scotch whiskeys  Scotch whiskeys are aged in cool, wet conditions, so they absorb water and become less alcoholic  American whiskeys are aged in warmer, drier conditions so they lose water and become more alcoholic  Whiskey is aged in wooden barrels, usually made from charred white oak  White oak is used because it is one of the few woods that can hold a liquid without leaking but which also allows the water in the whiskey to move back and forth within the pores of the wood, which helps to add flavor
  82. 82. Cont…..  United States these barrels are usually new and are only used once.  In most other countries it is common to reuse old barrels.  New barrels add more flavor than used barrels, resulting in differences in the taste of American and foreign whiskeys The aging process is a complex one, still not fully understood, but at least three factors are involved. First, the original mixture of water, alcohol, and congeners react with each other over time. Second, these ingredients react with oxygen in the outside air in oxidation reactions  Third, the water absorbs substances from the wood as it moves within it. (Charring the wood makes these substances
  83. 83. Bottling  Glass is always used to store mature whiskey because it does not react with it to change the flavor  Modern distilleries use automated machinery to produce as many as 400 bottles of whiskey per minute  The glass bottles move down a conveyor belt as they are cleaned, filled, capped, sealed, labeled, and placed in cardboard boxes
  84. 84. T H A N K Y OU