fermented products are: fermented products are those whose production involves the action of...
TRANSCRIPT
Fermented products are:Fermented products are:
Fermented products are those whose production involves the action of microorganisms or enzymes which cause desirable biochemical changes and significant modification to the food.
Origins of Some FermentedOrigins of Some Fermented ProductsProductsFoodFood Approx. year Approx. year
ofof
introductionintroduction
RegionRegion
MushroomsMushrooms
Soya sauceSoya sauce
WineWine
Fermented milkFermented milk
CheeseCheese
BeerBeer
BreadBread
Fermented Fermented meatmeat
Sourdough Sourdough breadbread
Fish sauceFish sauce
TeaTea
4000 BC4000 BC
3000 BC3000 BC
3000 BC3000 BC
3000 BC3000 BC
2000 BC2000 BC
2000 BC2000 BC
1500 BC1500 BC
1500 BC1500 BC
1000 BC1000 BC
1000 BC1000 BC
200 BC200 BC
ChinaChina
China, Korea, JapanChina, Korea, Japan
North Africa, EuropeNorth Africa, Europe
Middle EastMiddle East
Middle EastMiddle East
North Africa, ChinaNorth Africa, China
Egypt, EuropeEgypt, Europe
Middle EastMiddle East
EuropeEurope
Southeast Asia, North Southeast Asia, North AfricaAfrica
ChinaChina
Fermentation processes:Fermentation processes:
Lactic acidLactic acid AlcoholicAlcoholic Acetic acidAcetic acid Propionic acidPropionic acid
Fermented foodsFermented foods
BeveragesBeverages Dairy productsDairy products CerealsCereals Meat and fishMeat and fish Fruits and vegetablesFruits and vegetables
BeveragesBeverages
BeerWineSakeCiderspirits
Dairy productsDairy products
CheeseYoghurtKefirKurut -dry yoghurt ballKumis – alcoholic beverage from mari’s milk
CerealsCereals
BreadsRollsDosa (fermented crepe made from fermented rice and black lentils), idli (cakes 2-3 inches in diameter made by steaming a batter consisting of fermented rice and black lentils), adai (dosa); lao-chao (rice) , kenkey (sourdough dumpling made or corn such as sadza or ugali), ogi (fermented cereal porridge)Injera (flat pancakes made of iron rich teff (grass specie) flour)
Meat and FishMeat and Fish
Jerky, country ham, salami, pepperonipickled meat
Fish sauce, bagoong (mixture fish and brine, traditionally left to ferment for 10 to 12 months until it produces bubbles and acquires its characteristic pungent
odor.
Fruits & vegetablesFruits & vegetables
Pickled fruits & vegetablesOlivesSauerkraut
Contribution of the Contribution of the fermented foods:fermented foods:
Enrichment of the human dietEnrichment of the human diet Preservation of substantial amounts of foodPreservation of substantial amounts of food Enrichment of nutritional value of food Enrichment of nutritional value of food
(vitamins, proteins, essential amino acids (vitamins, proteins, essential amino acids etc]etc]
Detoxification of food (flatulence-causing Detoxification of food (flatulence-causing sugars, lectins, phytates etc] sugars, lectins, phytates etc]
Decrease the cooking time and fuel Decrease the cooking time and fuel requirementsrequirements
Preservation principle:Preservation principle:
To hinder (delay) the growth of food spoilage microorganisms
Alcoholic fermentation:Alcoholic fermentation:
Simple sugars yeasts > ethanol
Saccharomyces cerevisiae
Special flavors and aromas of beers arise from minor biochemical reactions
Major Reaction: Glucose to Carbon Dioxide and Ethanol
YeastYeast
Saccharomyces sp.Saccharomyces sp.
Yeasts involve in Yeasts involve in fermentation should fermentation should possess:possess:
Rapid and relevant carbohydrate Rapid and relevant carbohydrate fermentation ability;fermentation ability;
Appropriate flocculation and Appropriate flocculation and sedimentation characteristics;sedimentation characteristics;
Genetic stability;Genetic stability; OsmotoleranceOsmotolerance
Yeasts involve in Yeasts involve in fermentation should fermentation should possess:possess:
Ethanol toleranceEthanol tolerance Ability to produce elevated Ability to produce elevated
concentration of ethanol;concentration of ethanol; High cell viability for recycling;High cell viability for recycling; Temperature tolerance.Temperature tolerance.
Alcoholic fermentation is Alcoholic fermentation is affected by:affected by:
Oxygen supplyOxygen supplySugar contentSugar contentAlcohol contentAlcohol contentTemperatureTemperature
Alcoholic fermentation:Alcoholic fermentation:
Unlimited oxygen supply - Unlimited oxygen supply - cell growthcell growth
Limited oxygen supply - Limited oxygen supply - alcohol productionalcohol production
BeerBeer
A diluted solution of ethanol with a characteristic flavour arising from the use of malt as predominant source of carbohydrates and other yeast nutrients and hops as a source of bitter components.
Kinds of beerKinds of beer
Lager - produced by bottom Lager - produced by bottom fermen- ting yeasts fermen- ting yeasts ( Saccharomyces uvarum) . ( Saccharomyces uvarum) .
Ale - produced by top Ale - produced by top fermenting yeasts fermenting yeasts ( Saccharomyces cerevisiae)( Saccharomyces cerevisiae)
Production of beer:Production of beer:
MaltingMalting MashingMashing Boiling of wort with hopsBoiling of wort with hops FermentationFermentation StorageStorage
Production of beerProduction of beer
MaltMalt
Made from barley that has Made from barley that has been allowed to been allowed to germinate.germinate.
Germination produces Germination produces enzymes that during enzymes that during mashing converts starch mashing converts starch into simpler sugars and into simpler sugars and proteins into peptides. proteins into peptides.
This malt is then used by This malt is then used by the yeast in the the yeast in the fermentation process.fermentation process.
Before mashing the malt Before mashing the malt may be roasted to darken may be roasted to darken the color and harden a the color and harden a beer.beer.
barley
Malting (preparation of Malting (preparation of malt):malt):
Soaking barley grains in water Soaking barley grains in water at 10-15 at 10-15 00CC
Germination of barley grains at Germination of barley grains at 16-21 16-21 00C for 5-7 daysC for 5-7 days
Separation germs and sprouts Separation germs and sprouts Crushing the maltCrushing the malt
Mashing (preparation of Mashing (preparation of wort)wort)
Mixing malt with water at 38-50 Mixing malt with water at 38-50 00C (protein hydrolysis)C (protein hydrolysis)
Saccharafication of malt at 65-70 Saccharafication of malt at 65-70 00C (hydrolysis of starches to C (hydrolysis of starches to simple sugars)simple sugars)
Inactivation of enzymes at 75 Inactivation of enzymes at 75 00CC Separation of insoluble materials.Separation of insoluble materials.
WortWort
• Brewers' wort commonly has 8-14% total solids. Brewers' wort commonly has 8-14% total solids. • 90-92% are carbohydrates: glucose, fructose, 90-92% are carbohydrates: glucose, fructose,
maltose, sucrose, maltotriose.maltose, sucrose, maltotriose.• Nitrogenous compounds, such as, amino acids. Nitrogenous compounds, such as, amino acids. • Vitamins: biotin, inositol, pantothenic acid, Vitamins: biotin, inositol, pantothenic acid,
pyridoxine, and thiamine are present in wort and pyridoxine, and thiamine are present in wort and utilized by Brewers' yeast. utilized by Brewers' yeast.
• Phosphates, chlorides, sulfates and other anions Phosphates, chlorides, sulfates and other anions are present with the cations Na, K, Ca, Mg, Fe, are present with the cations Na, K, Ca, Mg, Fe, Cu, and Zn. Cu, and Zn.
Hops are the flowering portion of the hop vine.These flowers not only fight off bacterial infections in the beer, they aid in clarification of the beer, stabilize the flavor, help retain head, and aid in ones ability to drink the beer.
Hop oils are produced in the Lupulin glands of the flower. These oils are non-polar, and can only be extracted through a short boiling and contribute to the bitterness of a beer.
HOPSHOPS
Boiling of wort with hops is Boiling of wort with hops is done to:done to:
concentrate itconcentrate it sterilize itsterilize it inactivate enzymesinactivate enzymes extract soluble substances from hopsextract soluble substances from hops coagulate and precipitate proteinscoagulate and precipitate proteins contribute antiseptic resins: contribute antiseptic resins:
humulone, cohumulone, adhumulone.humulone, cohumulone, adhumulone.
FermentationFermentation
Fermentation of beerFermentation of beer
Pitching (inoculation)- 1lbs of yeasts Pitching (inoculation)- 1lbs of yeasts per barrel of wortper barrel of wort
Lager beer is fermented at 7-15 Lager beer is fermented at 7-15 00CC Ale beer is fermented at 18-22 Ale beer is fermented at 18-22 00CC Fermentation - 9 daysFermentation - 9 days At the end of fermentation yeasts At the end of fermentation yeasts
are skimmed (top-fermenting) or are are skimmed (top-fermenting) or are cropped (bottom-fermenting).cropped (bottom-fermenting).
Fermentation of AlesFermentation of Ales
Top fermenting-rise to the surface. Top fermenting-rise to the surface. Warmer temps- 60-70FWarmer temps- 60-70F More rapid growthMore rapid growth Create more estersCreate more esters Complex and FruityComplex and Fruity Ales, porters, stouts, and Ales, porters, stouts, and
wheat beers. wheat beers.
Fermentation of LagerFermentation of Lager
Bottom fermenting-yeast settle Bottom fermenting-yeast settle to the bottom of the fermenter to the bottom of the fermenter as fermentation reaches as fermentation reaches completion.completion.
Colder tempeatures: 47-58FColder tempeatures: 47-58F Slower growthSlower growth Crisp and hoppy like a pilsner or Crisp and hoppy like a pilsner or
sweet and malty like a sweet and malty like a Dopplebock. Dopplebock.
Examples: Pilsners, Bocks, and Examples: Pilsners, Bocks, and American malt liquors. American malt liquors.
Storage and packagingStorage and packaging
after fermentation beer is stored after fermentation beer is stored (lagered) at 0 C (several weeks to (lagered) at 0 C (several weeks to several months) to remove the “green” several months) to remove the “green” flavors caused by diacetyl and flavors caused by diacetyl and acetaldehyde which can impact the acetaldehyde which can impact the taste adversely as humans can taste taste adversely as humans can taste them at very low concentrations them at very low concentrations
clarified or filteredclarified or filtered pasteurized at 60 C shortlypasteurized at 60 C shortly carbonated to COcarbonated to CO22 content 0.45-0.52% content 0.45-0.52% packaged to cans or bottles.packaged to cans or bottles.
Beer defects (off flavour) Beer defects (off flavour) may be due to:may be due to:
butyric (butyric (ClostridiumClostridium sp.) or lactic acid sp.) or lactic acid fermentation during mashing process.fermentation during mashing process.
Inoculum contaminated with wild Inoculum contaminated with wild yeasts or lactic acid bacteria. yeasts or lactic acid bacteria. - Yeasts may - Yeasts may produce off flavor. produce off flavor. -Bacteria may produce sour taste -Bacteria may produce sour taste and/or silky turbitidy.and/or silky turbitidy.
WINESWINES
Products obtained by alcoholic fermentation of grapes, grape juices, fruit juices, berries, rhubarb, honey etc by yeasts.
Wine –definition of termsWine –definition of terms
Vintage – year grapes are grown and Vintage – year grapes are grown and harvested.harvested.
Dry – wine with no sugar after fermentationDry – wine with no sugar after fermentation Sweet – wine with small amount of sugar left Sweet – wine with small amount of sugar left
overover Body – the weight of wineBody – the weight of wine Style – overall impression of wineStyle – overall impression of wine Bouquet – a wine scent that comes from wine Bouquet – a wine scent that comes from wine
making processmaking process Aromatic – components of wine scent that Aromatic – components of wine scent that
comes from grape itselfcomes from grape itself
Wine – Basic typesWine – Basic types
Five basic types of wine are: Five basic types of wine are: Red Wine Red Wine White Wine White Wine Rose Wine Rose Wine Sparkling Wine - carbonated Sparkling Wine - carbonated Fortified Wine - high alcohol content Fortified Wine - high alcohol content
– Sherry - Spanish style wine (amber to brown) can Sherry - Spanish style wine (amber to brown) can be made sweet or not sweet. be made sweet or not sweet.
– Port - Sweet red wine originally from Portugal Port - Sweet red wine originally from Portugal – Madeira - from Madeira Islands made from Madeira - from Madeira Islands made from
cooked grapes & aged cooked grapes & aged – Marsala - Italian wine made from concentrated Marsala - Italian wine made from concentrated
grape juicegrape juice..
Kinds of winesKinds of wines
still winesstill wines sparkling winessparkling wines artificially carbonated winesartificially carbonated wines
Kinds of winesKinds of wines
Dry vs. sweet winesDry vs. sweet wines Unfortified vs. fortified winesUnfortified vs. fortified wines Red vs. white winesRed vs. white wines Grape vs. fruit winesGrape vs. fruit wines Table vs. dessert winesTable vs. dessert wines
How wine is madeHow wine is made
Harvesting --- Sugar/Acid RatioHarvesting --- Sugar/Acid Ratio
Pressing Techniques -- Red, White or Pressing Techniques -- Red, White or
Rose?Rose?
FermentationFermentation
MaturingMaturing
To bottleTo bottle
Grape used for production Grape used for production of wineof wine
Varies in grape species and cultivarsVaries in grape species and cultivars• Vitis vinifera, V. labruscaVitis vinifera, V. labrusca• Cabernet Sauvignon, Chardonnay, Gamay, Mission, etc. refer to Cabernet Sauvignon, Chardonnay, Gamay, Mission, etc. refer to
different varieties or cultivars of the different varieties or cultivars of the Vitis viniferaVitis vinifera
Cabernet SauvignonCabernet Sauvignon ChardonnayChardonnay Gamay Gamay MissionMission
• Different in compositions (sugar contents, pigmentation, etc.)Different in compositions (sugar contents, pigmentation, etc.)• Different climates and soil preferenceDifferent climates and soil preference• Wine quality varies greatly Wine quality varies greatly
– Climate factors have important effect on grape quality and maturityClimate factors have important effect on grape quality and maturity
Grape CompositionGrape Composition
Water 70-85% of the juice volumeWater 70-85% of the juice volume About 20% sugarAbout 20% sugar
• Simple sugars largest constituent of grapes or mustSimple sugars largest constituent of grapes or must• Important for Important for S. cerevisiaeS. cerevisiae to produce ethanol to produce ethanol• Glucose (~50%), Fructose (~50%, increase in over-ripened Glucose (~50%), Fructose (~50%, increase in over-ripened
grapes), sucrose (<1%, in grapes), sucrose (<1%, in V. labruscaV. labrusca up to 10%) up to 10%)• Other sugars very low conc.Other sugars very low conc.
Sugar content in final productSugar content in final product• ““dry”: 0.1%-0.2%dry”: 0.1%-0.2%• ““sweet” >10g/Lsweet” >10g/L• ““very sweet” as much as 100g/L-200g/Lvery sweet” as much as 100g/L-200g/L
Organic AcidsOrganic Acids
• Second in content constituent in mustSecond in content constituent in must• Very important in wine qualityVery important in wine quality
– Provide low and well buffered pH (3.0-3.5)Provide low and well buffered pH (3.0-3.5)– Antimicrobial activitiesAntimicrobial activities– Stabilizes anthocyanins (color, antioxidant, Stabilizes anthocyanins (color, antioxidant,
desirable flavor)desirable flavor)– Volatile acids (acetic acid and others) very lowVolatile acids (acetic acid and others) very low– Fixed acids (malic acid and tartaric acid ~5:1) Fixed acids (malic acid and tartaric acid ~5:1)
important to maintain the right acidity of wine important to maintain the right acidity of wine and anti-spoilage, affected by environmental and anti-spoilage, affected by environmental factorsfactors
Nitrogenous Nitrogenous CompoundsCompounds
Total N content in must range from 0.2g/L Total N content in must range from 0.2g/L to 0.4g/Lto 0.4g/L
Generally adequate for rapid growth of Generally adequate for rapid growth of yeastyeast
Biogenic amines (histamine and tyramine) Biogenic amines (histamine and tyramine) in wine (by wine bacteria) can cause in wine (by wine bacteria) can cause adverse reactionsadverse reactions
Ethyl carbamate potential carcinogen, Ethyl carbamate potential carcinogen, concentration increased by heat treatment concentration increased by heat treatment and high urea concentration.and high urea concentration.
PolyphenolsPolyphenols
Polyphenolic compounds naturally Polyphenolic compounds naturally occurring in grapes, some are occurring in grapes, some are introduced laterintroduced later
Contribute to color, flavor, aroma, Contribute to color, flavor, aroma, mouth feel to the winemouth feel to the wine
Production of wineProduction of wine
After harvesting: After harvesting: The grapes are transported to The grapes are transported to
the winery where they undergo the winery where they undergo destemming and crushing. destemming and crushing.
There are a variety of presses There are a variety of presses that are used to produce the that are used to produce the juice, which is called “must”. juice, which is called “must”.
The sugar in the wine is used The sugar in the wine is used by the yeast to produce ethyl by the yeast to produce ethyl alcohol and carbon dioxide alcohol and carbon dioxide gas, thus making wine. gas, thus making wine.
The type of yeast can affect The type of yeast can affect the qualities of the the qualities of the wine as will other wine as will other compounds in the wine compounds in the wine - some naturally - some naturally occurring and some that are occurring and some that are byproducts of the byproducts of the winemaking process.winemaking process.
Crusher Small Bladder Press
Large Rotary Press
Steps involve in Steps involve in fermentation of wine:fermentation of wine:
Preparation of must (grape juice, Preparation of must (grape juice, crushed grapes, fruit juice]. crushed grapes, fruit juice].
inoculation of must with wine inoculation of must with wine yeasts (2-5% ].yeasts (2-5% ].
aeration of must to encourage the aeration of must to encourage the growth of yeasts and to facilitate growth of yeasts and to facilitate the extraction of pigments from a the extraction of pigments from a skin (mixing must twice a day ].skin (mixing must twice a day ].
Steps involve in Steps involve in fermentation of wine:fermentation of wine:
Active fermentation: Active fermentation: - red wines 24 -27 - red wines 24 -27 00C; 3-C; 3-5 days; - white 5 days; - white wines 10-21 wines 10-21 00C; 7-14 days;C; 7-14 days;
separation of fermented juice from residue separation of fermented juice from residue (pomace);(pomace);
placing fermented juice under light COplacing fermented juice under light CO22 pressurepressure
secondary fermentation: 21-29 secondary fermentation: 21-29 00C, 7-11 days.C, 7-11 days. aging of wines.aging of wines.
Differences in making red and white Differences in making red and white winewine
White Wine: White Wine: Grapes for white wine are Grapes for white wine are
harvested and pressed. harvested and pressed. The must is fermented in The must is fermented in
stainless steel tanks. stainless steel tanks. Some white wines, such as Some white wines, such as
Chardonnay, is aged in Chardonnay, is aged in oak barrels. oak barrels.
The wine is bottled The wine is bottled Most white wines are not Most white wines are not
bottle aged but consumed bottle aged but consumed with in 3 years of bottling. with in 3 years of bottling.
However, an exception is However, an exception is particularly fine wines particularly fine wines made from Chardonnay made from Chardonnay and Champagne. and Champagne.
Red Wine: Red Wine: Grapes for red wine are Grapes for red wine are
harvested, crushed. harvested, crushed. The must is left with the The must is left with the
skins during skins during fermentation to produce fermentation to produce the red color. the red color.
Red wine is commonly Red wine is commonly aged in oak barrels for 6 aged in oak barrels for 6 to 24 months. to 24 months.
The wine is bottled. The wine is bottled. Many red wines are Many red wines are
ready to drink after ready to drink after bottling. bottling.
However, some red However, some red wines, such as Cabernet wines, such as Cabernet Sauvignon, will benefit Sauvignon, will benefit with some bottle age.with some bottle age.
Production of Blush & Sparkling Production of Blush & Sparkling WinesWines
Blush Wine: Blush Wine: Red grapes are Red grapes are
harvested for Rose or harvested for Rose or Blush wine. Blush wine.
Before fermentation the Before fermentation the must is left with the skin must is left with the skin for a short time. for a short time.
The must is fermented in The must is fermented in stainless steel tanks. stainless steel tanks.
If a sweet wine is desired If a sweet wine is desired then the fermentation is then the fermentation is stopped before all of the stopped before all of the sugar is consumed. sugar is consumed.
The wine is bottled The wine is bottled Blush wines are not Blush wines are not
commonly bottle commonly bottle aged but aged but consumed consumed within 3 years of within 3 years of bottling. bottling.
Champagne (Sparking) Champagne (Sparking) Wine: Wine: Grapes for sparking wine are Grapes for sparking wine are
harvested and pressed. harvested and pressed. It is fermented like a white It is fermented like a white
wine. wine. More sugar and yeast is added More sugar and yeast is added
to the wine. to the wine. The wine is bottled. The wine is bottled. The additional sugar and yeast The additional sugar and yeast
produce carbon dioxide, which produce carbon dioxide, which carbonates the wine. carbonates the wine.
The second fermentation is The second fermentation is stopped. stopped.
Most sparkling wines are made Most sparkling wines are made to drink young. But, fine to drink young. But, fine Champagne will benefit with Champagne will benefit with additional bottle age.additional bottle age.
Production of fortified wineProduction of fortified wine
Grapes for fortified wines Grapes for fortified wines are harvested like for other are harvested like for other wines. wines.
Depending on the type of Depending on the type of wine, the must may be wine, the must may be handled in different ways to handled in different ways to intensify the flavor before intensify the flavor before and during fermentation. and during fermentation.
Most fortified wines have an Most fortified wines have an addition of alcohol (brandy) addition of alcohol (brandy) to stop fermentation and to stop fermentation and increase the alcohol increase the alcohol content. content.
Fortified wine maybe aged Fortified wine maybe aged in oak barrels before in oak barrels before bottling. bottling.
Many fortified wines will Many fortified wines will benefit with bottle age.benefit with bottle age.
Aging of wineAging of wine
Once fermentation is complete, the Once fermentation is complete, the
wine can be transferred to oak barrels wine can be transferred to oak barrels for aging for 6 to 24 months. But, not for aging for 6 to 24 months. But, not all wine is oak aged. all wine is oak aged.
The barrels are usually made from The barrels are usually made from either French or American Oak, which either French or American Oak, which give differing qualities to the wine. give differing qualities to the wine.
Some wine is aged in old barrels and Some wine is aged in old barrels and some in new to produce different some in new to produce different characteristics, as well. characteristics, as well.
The wine maker will then blend the The wine maker will then blend the various lots of wine to produce a various lots of wine to produce a finished wine ready for bottling. finished wine ready for bottling.
Fermentation Tanks
Barrel filling
Barrel aging
Active Yeast Cells
Bottling and storage of wineBottling and storage of wine
After the aging of wine is After the aging of wine is
complete it is transferred complete it is transferred to bottles. to bottles.
Most wine is consumed Most wine is consumed within three years of within three years of bottling. bottling.
But some fine wines gain But some fine wines gain added flavor and bouquet added flavor and bouquet with time in the bottle if it with time in the bottle if it is stored at 50 to 60 F. But, is stored at 50 to 60 F. But, humidity is also important humidity is also important so that the corks do not so that the corks do not dry out, which spoils the dry out, which spoils the wine. wine.
The wines commonly aged The wines commonly aged in the bottle are: in the bottle are:
– Cabernet Sauvignon (Red) Cabernet Sauvignon (Red) – Pinot Noir (Red) Pinot Noir (Red) – Chardonnay (White) Chardonnay (White) – Champagne (White Sparkling) Champagne (White Sparkling) – Port Port – Sherry Sherry
Bottling line
Bottles being filled
Large Commercial Cellar
Small in-home cellar
Problem solvingProblem solving
Calculate the % [w/w] of EtOH in wine. Assume that at fermentation starting point 30 kg of must contained 26% of sucrose. The fermentation ceased at 2% concentration of sugar. The yield of conversion of sugar to ethanol was 94%.
Calculation steps:Calculation steps:
C6 H12O6 = 2 C2 H5 OH + 2 C02
1. Calculate the amount of sugar in must.
M1 = 30 * 0.26 = 7.8 kg
Calculation steps:Calculation steps:
2. Calculate the final weight of must (M) at the end of fermentation process.
M = M0 - M2 + M3
M0 - initial weight of must;M2 - weight of sugar used during fermentation;M3- weight of produced alcohol.
Calculation steps:Calculation steps:
3. Calculate the weight of sugar in wine. M4 = M * 0.02
4. Calculate the weight of sugar fermen- ted to alcohol. M5 = (7.8 - M4 ) * 0.94 M5 = (7.8 - M * 0.02) * 0.94
Calculation steps:Calculation steps:
5. Calculate the weight of produced alcohol.
C6 H12O6 = 2 C2 H5 OH + 2 C02 180 92 M5 M3
--------------------------------- M3 = 92 * M5 /180 = 92 * ( 7.8 - M4)*0.94/180 = 92 * ( 7.8 - M * 0.02) * 0.94/180
Calculation steps:Calculation steps:
6. Calculate the final weight of wine (M) M = M0 - M2 + M3
M = 30 - (7.8 – M*0.02)+ + 92*(7.8 - 0.02*M) *0.94/180
M = 26.22 kg of wine
Calculation steps:Calculation steps:
7. Calculate the weight of produced ethanol.
M3 = 92 * (7.8 - 26.22 *0.02) * 0.94/180
M3 = 3.495 kg of ethanol
Calculation steps:Calculation steps:
8. Calculate [ % ; w/w) of ethanol in wine.
[%] = M3/M * 100 [%] = 3.495/26.22 *100 [%] = 13.3%
Factors affecting the wine Factors affecting the wine spoilage:spoilage:
Acidity - the lower the pH the less likely Acidity - the lower the pH the less likely the wine will spoil. Molds, yeasts, acetic the wine will spoil. Molds, yeasts, acetic acid bacteria would not be stopped by acid bacteria would not be stopped by any pH normal to wines: most wines - any pH normal to wines: most wines - pH 3.5-4.0;pH 3.5-4.0;
Sugar content < 0.1%;Sugar content < 0.1%; Ethanol content . 14%Ethanol content . 14% Temperature - spoilage most rapid at Temperature - spoilage most rapid at
20-30 20-30 ooC.C.
Yeasts of the genera Dekkera & Brettanomyces
“Brettanomyces sp. has been identified in spoilage
from all wine-producing areas of the world”
Fugelsang, K.C. (1997) In Wine Microbiology, Chapman & Hall
Responsible for the production of off-flavours in wine (known as “phenolic taint”, “horse sweat”,or“Brett flavour”)
I II III
R= H I=p-coumaric acid; II=4-vinylphenol; III=4-ethylphenol
R=OCH3 I=Ferulic acid; II=4-vinylguaiacol; III=4-ethylguaiacol
o
Evaluating WineEvaluating Wine
BodyBody• Light, medium, or full? (think about the difference between Light, medium, or full? (think about the difference between
skim milk, whole milk, and cream)skim milk, whole milk, and cream) TextureTexture
• How does the wine feel in your mouth (e.g. soft, sharp, How does the wine feel in your mouth (e.g. soft, sharp, smooth)? smooth)?
• If you had to describe the wine as a fabric, what would it be?If you had to describe the wine as a fabric, what would it be? FlavorFlavor
• What specific components can you taste? It may help to run What specific components can you taste? It may help to run through lists of choices.through lists of choices.
BalanceBalance• Is the wine overwhelmed by any components (alcohol, Is the wine overwhelmed by any components (alcohol,
acidity, tannin, fruitiness, sugar)? acidity, tannin, fruitiness, sugar)? LengthLength
• How long do the flavors and aromas linger after swallowing? How long do the flavors and aromas linger after swallowing?
Evaluating Wine – Smell Evaluating Wine – Smell (aroma and bouquet)(aroma and bouquet)
• Aerate the wine by swirling it in the glassAerate the wine by swirling it in the glass• Stick your nose in the glass and inhaleStick your nose in the glass and inhale
• Aroma traditionally refers to grape- traditionally refers to grape-associated smellsassociated smells
• Bouquet refers to other smells (e.g. oak, refers to other smells (e.g. oak, vanilla, nutty or buttery)vanilla, nutty or buttery)
Aroma WheelAroma Wheel
Evaluating Wine - TasteEvaluating Wine - Taste
• Evaluate the first impression of a wine on your Evaluate the first impression of a wine on your tongue by taking a sip but don’t swallowing yettongue by taking a sip but don’t swallowing yet
Following this:Following this:
• Swirl the wine around in your mouth, draw in Swirl the wine around in your mouth, draw in some airsome air
• Evaluate body & texture as well as flavor and Evaluate body & texture as well as flavor and balancebalance
• Evaluate the flavors and aromas that last after Evaluate the flavors and aromas that last after swallowing the wineswallowing the wine
• Evaluate Evaluate lengthlength of finish (the longer the better) of finish (the longer the better) (ie. How long the flavor last)(ie. How long the flavor last)
Production of ethanolProduction of ethanol
Starch pretreatment: Starch pretreatment: -gelatinization, -gelatinization, - -liquefaction, liquefaction, -saccharification -saccharification
FermentationFermentation DistillationDistillation
Type of whiskyType of whisky
• Malt whiskyMalt whisky• Pot still whiskyPot still whisky• Grain whiskyGrain whisky• Blended whiskyBlended whisky• Straight whiskyStraight whisky
By locationBy location• Scotch whisky (Scotch)Scotch whisky (Scotch)• Irish whiskey Irish whiskey • Kentucky whiskey Kentucky whiskey
(Bourbon)(Bourbon)• Tennessee WhiskyTennessee Whisky• Canadian whiskyCanadian whisky
Production of WhiskyProduction of Whisky
FermentationFermentation• The dried malt (or The dried malt (or
other grains) is ground other grains) is ground and soaked in water, and soaked in water, dissolving the sugar dissolving the sugar and producing and producing wortwort
• Yeast is then added, Yeast is then added, and the wort is allowed and the wort is allowed to ferment, producing to ferment, producing washwash or or low beerlow beer. .
DistillationDistillation
Distillation - Pot StillDistillation - Pot Still
Heat is applied directly to the pot Heat is applied directly to the pot containing the fermented wortcontaining the fermented wort
Alcohol, water and flavor Alcohol, water and flavor components evaporatecomponents evaporate
The first distillation produces so-The first distillation produces so-called 'low wines', (25-35%)called 'low wines', (25-35%)
The second distillation produces The second distillation produces the colourless spirit, collected at the colourless spirit, collected at about (70%)about (70%)
Whisky productionWhisky production AgingAging
• In new (for Bourbon) or old, charred (Bourbon & In new (for Bourbon) or old, charred (Bourbon & Scotch) or uncharred (Irish Whiskey) oak Scotch) or uncharred (Irish Whiskey) oak barrels/casksbarrels/casks
• Typically causes the brown color to develop over Typically causes the brown color to develop over timetime
• 0.5 – 2.0% volume evaporates each year of aging 0.5 – 2.0% volume evaporates each year of aging (making long-aged whiskies more expensive to (making long-aged whiskies more expensive to produce)produce)
BottlingBottling• Mature whisky is usually blendedMature whisky is usually blended• Water is usually added (to reduce alcohol content)Water is usually added (to reduce alcohol content)
Chill FiltrationChill Filtration• Whisky is chilled to near 0°C (32°F) and passed Whisky is chilled to near 0°C (32°F) and passed
through a fine filter through a fine filter • Removes some of the compounds accumulated Removes some of the compounds accumulated
during distillation or aging, prevents the whisky during distillation or aging, prevents the whisky from becoming hazy when chilledfrom becoming hazy when chilled
• Can also remove some of the flavor and body from Can also remove some of the flavor and body from the whiskythe whisky
Scotch Whisky (Barley Malt Scotch Whisky (Barley Malt Whisky)Whisky)
Distilled at a Scottish Distilled at a Scottish distillery from water and distillery from water and malted barleymalted barley
Only other whole grains may Only other whole grains may be addedbe added
Must have an alcoholic Must have an alcoholic strength of less than 94.8% strength of less than 94.8% by volume by volume
Must be matured in Scotland Must be matured in Scotland in charred oak casks for at in charred oak casks for at least three years (giving it least three years (giving it smoky & earthy overtones)smoky & earthy overtones)
Most single malts are aged Most single malts are aged for at least 8 yearsfor at least 8 years
Must not contain any added Must not contain any added substance other than water substance other than water and caramel colourand caramel colour
Typically distilled twiceTypically distilled twice
Irish Whisky (Barley Malt Irish Whisky (Barley Malt Whisky)Whisky)
Similar to Scotch whisky in Similar to Scotch whisky in ingredients & productioningredients & production
Typically distilled 3 timesTypically distilled 3 times Aged in Aged in uncharreduncharred barrels barrels
(unlike Scotch or Bourbon) (unlike Scotch or Bourbon) Pure pot still whisky Pure pot still whisky
Canadian WhiskyCanadian Whisky
Must be barrel aged Must be barrel aged at least three yearsat least three years
Most are blended Most are blended multi-grain whiskiesmulti-grain whiskies
Traditionally called Traditionally called “rye whisky," “rye whisky," contains proprietary contains proprietary blends of corn, blends of corn, barley, and rye. barley, and rye.
Lactic Acid BacteriaLactic Acid Bacteria
The lactic acid bacteria can be divided into two groups The lactic acid bacteria can be divided into two groups based on the end products of glucose metabolism.based on the end products of glucose metabolism.
Those that produce lactic acid as the major or sole Those that produce lactic acid as the major or sole product of glucose fermentation are designated product of glucose fermentation are designated homofermentative.homofermentative.
Those that produce equal amounts of lactic acid, Those that produce equal amounts of lactic acid, ethanol and CO2 are termed heterofermentative.ethanol and CO2 are termed heterofermentative.
The homofermentative bacteria are able to extract The homofermentative bacteria are able to extract about twice as much energy from a given quantity of about twice as much energy from a given quantity of glucose as the those heterofermentative glucose as the those heterofermentative .
Lactic Acid BacteriaLactic Acid Bacteria
All members of Pediococcus, Lactococcus, All members of Pediococcus, Lactococcus, Streptococcus, Vagococcus, along with some Streptococcus, Vagococcus, along with some lactobacilli are homofermenters.lactobacilli are homofermenters.
Carnobacterium, Oenococcus, Enterococcus, Carnobacterium, Oenococcus, Enterococcus, Lactosphaera, Weissells and Lecconostoc and Lactosphaera, Weissells and Lecconostoc and some Lactobacilli are heterofermenterssome Lactobacilli are heterofermenters
The heterolactics are more important than the The heterolactics are more important than the homolactics in producing flavour and aroma homolactics in producing flavour and aroma components such as acetylaldehyde and diacetyl.components such as acetylaldehyde and diacetyl.
Lactic Acid FermentationLactic Acid Fermentation
LactobacilliLactobacilli
Streptococci (dairy streptococci)Streptococci (dairy streptococci)
PediococciPediococci
LeuconostocsLeuconostocs
Lactic bacteriaLactic bacteria
Pediococcus - used in production of fermented meats
Leuconostoc cremoris – used in the production of buttermilk and sour cream
Lactobacillus bulgaricus – used in the production of yogurt
Benefits from Lactic Acid Benefits from Lactic Acid FermentationFermentation
Alteration of flavour, texture, and Alteration of flavour, texture, and appearanceappearance
enhancement of nutritional valueenhancement of nutritional value Retardation of food spoilage and Retardation of food spoilage and
reduction of microbial contaminationreduction of microbial contamination Probiotic effect- prolongation of life: Probiotic effect- prolongation of life:
(Metchnikoff 1908) due to lactase, (Metchnikoff 1908) due to lactase, metabolism of dietary cholesterol, metabolism of dietary cholesterol, detoxification of potential carcinogens.detoxification of potential carcinogens.
Sequence in changes in raw milk Sequence in changes in raw milk in relation to acid concentrationin relation to acid concentration
Sauerkraut ProductionSauerkraut Production
Lactic acid bacteria Lactic acid bacteria are the primary group are the primary group of microorganisms of microorganisms involved in sauerkraut involved in sauerkraut fermentationfermentation
Shredded cabbage is Shredded cabbage is placed in a jar and placed in a jar and salt is added to a final salt is added to a final concentration of 2- concentration of 2- 2,5%2,5%
Sauerkraut ProductionSauerkraut Production
sugar contained in the cabbage is sugar contained in the cabbage is converted to lactic acidconverted to lactic acid lactic acid lactic acid fermentationfermentation
Fermentation is completed approx. after 20 days at room temperature,
Sequence of acid fermentation Sequence of acid fermentation in sauerkraut manufacturein sauerkraut manufacture
Leuconostoc mesenteroides an acid and gas producing coccusLactobacillus plantarum and bacilli that produce acid and a small amount of gasL. CucumerisLactobacillus pentoaceticus acid and gas producing bacilli(L. Brevis
Are fermented foods safer Are fermented foods safer than fresh foods?than fresh foods?
Cases of microbial food-borne infection have Cases of microbial food-borne infection have been reported in association with fresh been reported in association with fresh cheese, sausages, fermented fish and cheese, sausages, fermented fish and fermented cereals.fermented cereals.
Cases of microbial food intoxications due to Cases of microbial food intoxications due to mycotoxin contaminated raw material, mycotoxin contaminated raw material, production of microbial toxins, production of production of microbial toxins, production of mycotoxins by fungal have been reported.mycotoxins by fungal have been reported.
Toxic by-products (ethyl carbamate and Toxic by-products (ethyl carbamate and biogenic amines) may be produced.biogenic amines) may be produced.
Toxic by-products of Toxic by-products of fermenta tion:fermenta tion:
Ethyl Carbamate: a carcinogenic and Ethyl Carbamate: a carcinogenic and mutagenic compound which results mutagenic compound which results from the esterification of ethanol with from the esterification of ethanol with carbamic acid (NHcarbamic acid (NH22COOCCOOC22HH55- also - also known as urethane)known as urethane)
Biogenic amines - a mildly toxic Biogenic amines - a mildly toxic substances. 100-200 ppm; substances. 100-200 ppm; >1000ppm is supposed to elicit >1000ppm is supposed to elicit toxicity.toxicity.
Biogenic aminesBiogenic amines
Biogenic amines in Biogenic amines in fermented foodsfermented foods
Major risk enhancing Major risk enhancing factors:factors:
Use of contaminated raw materials.Use of contaminated raw materials. Lack of pasteurization.Lack of pasteurization. Poorely controlled natural Poorely controlled natural
fermentations.fermentations. Sub-optimal fermentation starters.Sub-optimal fermentation starters. Inadequate storage and maturation Inadequate storage and maturation
conditions.conditions. Consumption without prior cookingConsumption without prior cooking
How can these risk be How can these risk be minimized minimized
By ensuring wholesomeness of raw By ensuring wholesomeness of raw materials.materials.
Optimization of starter cultures by Optimization of starter cultures by conventional selection and mutation or conventional selection and mutation or by recombinant DNA manipulations.by recombinant DNA manipulations.
Good hygienic practices during Good hygienic practices during manufactu- ringmanufactu- ring
Adequate storageAdequate storage