Winemaking or vinification is the production of wine Although most wine is made from grapes Mead is a wine that is made with honey being the primary ingredient after water Wine Production ID: 935708
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Slide1
WINE PRODUCTION
INTRODUCTION
Winemaking, or vinification, is the production of wine.Although most wine is made from grapes.Mead is a wine that is made with honey being the primary ingredient after water.
Slide3Wine
Production
Slide4Red & White Wine Production
One of the first things they realized was that
red wine production
required that the grapes be fermented in contact with their skins. This gives the wine color and body. In contrast, most
white wine production
does not occur in contact with the grape skins. Whites are valued for their fresh fruit characteristics, and skin contact would impart unwanted bitter tannins.
Slide5Wine Production : Main
Steps
Viticulture
Harvesting
Stemming/Crushing
Fermentation
Draining
Pressing
Mixing
Clarification
Aging
Bottleing
Slide6Wine Production: Process
Slide7Wine Production
Factors which
inflence
grape’s flavor:
climate of the vineyard’s region
drainage around the vines
humidity of the region
sun exposure.
soil quality
1.
Viticulture
Slide8Wine Production
2. Harvesting
Grappes are
picked
up by hand or mechanically
Descision of harvest informed by level of sugar and acid
weather forecasts
Slide9Wine Production
3. 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.
Slide10Wine Production
4. 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.
5. 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.
Slide11Wine Production
6. 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.
7. Mixing
The free-run wine and press wine, always from the same source, are mixed together in appropriate ratios to obtain the desired balance.
Slide12Wine Production
8. 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
siphoning the liquid off the top of the fermenting vats after the solids have settled to the bottom
Slide13Wine Production
9. 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.
Slide14Wine Production
10.
Bottling
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, which are less subject to cork taint, are becoming increasingly popular.
Slide15Crushing and primary (alcoholic) fermentation
Crushing is the process when gently squeezing the berries and breaking the skins to start to liberate the contents of the berries.
the harvested grapes are sometimes crushed by trampling them barefoot or by the use of inexpensive small scale crushers.larger wineries, a mechanical crusher/destemmer is used.
Slide16Secondary (malolactic) fermentation and bulk aging
During the secondary fermentation and aging process, which takes three to six months, the fermentation continues very slowly.
The wine is kept under an airlock to protect the wine from oxidation.Proteins from the grape are broken down and the remaining yeast cells and other fine particles from the grapes are allowed to settle.The secondary fermentation usually takes place in either large stainless steel vessels with a volume of several cubic meters, or oak barrels, depending on the goals of the winemakers.
Slide17Malolactic fermentation
Malolactic fermentation occurs when lactic acid bacteria metabolize malic acid and produce lactic acid and carbon dioxide.
Malolactic fermentation can improve the taste of wine that has high levels of malic acid, because malic acid, in higher concentration.White wines vary in the use of malolactic fermentation during their making.
Slide18Preservatives
The most common preservative used in winemaking is sulfur dioxide.It added in one of the following forms: liquid sulfur dioxide, sodium or potassium metabisulphite. Another useful Sulfur dioxide has two primary actions, firstly it is an anti microbial agent and secondly an anti oxidant. In the making of white wine it can be added prior to fermentation and immediately after alcoholic fermentation is complete.
Slide19If added after alcoholic ferment it will have the effect of preventing or stopping malolactic fermentation, bacterial spoilage and help protect against the damaging effects of
oxygen.preservative
is potassium sorbate.
Slide20Bottling
A final dose of sulfite is added to help preserve the wine and prevent unwanted fermentation in the bott
Then filled in the bottel.
Slide2121
spirits
The word distillation comes (from the
Latin
destillare
meaning to drip) which is the extraction of higher alcohols from fermented drinks by using the action of heat to
vapourize
them. Basically what distillation is the
concentration or increasing of alcohol strength
Slide22A
distilled beverage, spirit, or liquor is an alcoholic
beverage containing ethanol that is produced by distilling (i.e., concentrating by distillation
) ethanol produced by means of fermenting grain, fruit, or vegetables. This excludes undistilled fermented beverages such as beer, wine, and cider
.
Vodka,
gin,
rakı,
baijiu, tequila, rum, whisky, brandy,
Singani
and
soju
are examples of distilled beveragesDefinition
Slide23The term
spirit refers to a distilled beverage that contains no added sugar and has at least 20% alcohol by volume (ABV).
Beer and wine, which are not distilled beverages, are limited to a maximum alcohol content of about 20% ABV, as most yeasts cannot reproduce when the concentration of alcohol is above this level; as a consequence,
fermentation ceases at that point.Hard liquor is used in North America and India to distinguish distilled beverages from undistilled ones
Slide24Raw materials of Distilled Spirits
The availability of this base ingredient and the uniqueness of the land which is it grown all play an integral part in the different complexities and qualities found in these distilled spirits.
Anything that can be fermented can be used as a raw material for spirits – whether fruit, grain or vegetable. Where sugar is present in the primary material, as in molasses or fruit, the fermentation can be started directly.
Some spirits can be made from one particular material only, (i.e. whiskey, vodka, genever), some schnapps and akvavit from grain. Other, such as Vodka, can be made from a broad range of raw materials, including various grains, potatoes, and even sugar cane and grapes
Slide25Methods
of Alcohol Separation
Two distinctively different methods to separate alcohol: Congelation method (freeze distillation) and the boiling method or (heat distillation)
which is commonly referred to as the distillation method. Congelation (cold extraction): separation by freezing below zero degrees Celsius or 31F degrees;
only problem with this method is that this is a dangerous method of separation,
most International countries do not officially recognize this method of alcohol separation and have banned its use making the method of alcohol separation illegal,
less than 2% of the worlds distilled spirits are made using this method.
Distillation (heat extraction):
separation by
vaporization
of the fermentable liquid at
78.5
degrees Celsius or 172
Degrees Fahrenheit to create alcohol’. scientifically the best separation method and research figures indicate that this method accounts for 98% of the worlds spirits produced, the most widely method officially recognized by International governments to separate alcohol for creating spirits which taxes and duties are levied.
Slide26Distillation
Water – boils at 100 C (212 F)
Ethanol – boils at 78.5 C (173.3 F)
Mixture is heated; ethanol gas is driven off at lower temperature; gathered in condenser – note, various devices added to minimize water vapor from escaping
Slide27Distilled Alcoholic Beverages - Whiskeys
Whiskey: made from malted barley, or malted barley + other grain
proof = twice concentration of alcohol (90 proof = 45% alcohol)
Scotch: made from barley malt; aged in charred casks
Bourbon: from Bourbon Co., Kentucky – 51+% corn
Tennessee sour mash: similar to bourbon; filtered through charcoal
Rye: 51% rye grain
Straight whiskey: <80 proof; aged 2+ years in new charred barrels
Slide28Principles of Distillation
Pot Still: (alembic or alambic)
This looks like a large copper kettle and is heated by direct heat. The vapours collect in the head and are led off through a narrow tube at the top, called the swan’s neck from where they go to the condenser. Here they are liquefied. Such a still is not very heat-efficient, but it produces spirits with character
.
Pot still distillation is a
small batch process,
This redistilling often several times is necessary to achieve the appropriate alcohol level.
Most spirits made with a pot still are double distilled, but sometimes it is done in three or even four stages (i.e. Irish whiskey, distilled three times).
Several spirits are produced using the Pot still: Cognac, brandy, Scotch malt whisky, Irish whiskey, American Bourbon whiskey, some rums (usually the darker ones) and some other spirits.
Pot Still: (alembic or
alambic
)
Slide29Principles
of Distillation
The Still man: separates the poisonous parts (methanol, propandl, butanol), from the required spirit (ethanol). The still
man identifies all these separations and parts by (a) tell by nose and (b) the rising hydrometer, the first and the last parts will not be included in the final spirit as they contain toxic compounds.
Continuous still:
(referred to as the Patent, Column or Coffey Still):
invented by Robert Stein in 1820, developed by
Aeneas
Coffey.C
onsists
of two tall columns, each about sixty feet in height, called the analyzer and the rectifier.
The
alcoholic wash is broken down into its constituent vapours, or analysed, in the analyzer, and the vapours are selectively condensed, or rectified, in the rectifier. Large coffey still (exterior view).Coffey still diagram. Small coffey still (interior view)
Maturing
and Oxidation
The barrel: most common vessel used for maturing spirits, usually 500-litre size (although smaller sizes can also be used
which restricts the oxygen intake and changes the character of the final spirit) wooden barrel help the chemical reactions, extraction of taste, extraction of bouquet and extraction of colour.
Evaporation
loss of spirit (like
angels share
contains dangerous fusel oils this
vaporises
first.
In summary the wooden barrel helps the spirit to;
change as the
congeners (fusels) interact with air filtering through the porous wooden barrels new congeners are absorbed from the wood itself, adding flavouring agents to the final spirit (flavours are married, blended). Not all spirits are aged. Wood finishes: More and more, some distilleries are producing whisky with various finishes, achieved by the last 6 months to 2 years of maturationbeing in ex-Sherry, ex-Port, ex-Madeira, Maturation periods: can differ (a minimum of 3 years before it can be legally called Irish or Scotch whiskey).
Used Bourbon cask
American white oak.
French oak cask
Slide32Brandies are distilled wines.
The most famous come from France. Cognac is one type.The fermented juices of many other fruits are also distilled.Liquers differ from brandy in that various flavoring agents are added. They have sugar and syrups added.
Brandies
Slide33By the 15th century, the English and Scots had begun distilling barley beer and, in the 16th century, cognac was prepared in France. Whiskeys were made in a similar way.
Once distilled, the mixture is diluted back to about 50% alcohol in general. Whiskeys are aged in (usually oak) barrels.
The inside of these barrels is often charred. The barrel provides some of the flavoring materials.
Slide34Scotch whiskeys have a characteristic taste because of the smoking process (over peat) used to dry the malt.
Bourbon whiskey is made from corn as the primary grain (
Zea mays, Poaceae) and was developed by the early Scottish (many of whom are called Scots-Irish) immigrants in Pennsylvania.These whiskies are aged for at least two years in new, charred oak barrels.
Slide35Aging of whiskey in charred white oak barrels
Slide36Other distilled beverages
Gin and vodka are distilled to a high percentage of alcohol and in the case of gin,
Juniperus communis, Cupressaceae, "berries" are added.These beverages can be distilled from almost any fermented mixture including potatoes, grains, etc.
Rum is made from fermented molasses or sugar cane juice.
Slide37Tequila and mescal
Tequila and mescal are distilled from
pulque made from various Agave species.
Slide3838
Fig:-Distillation process
Slide3939
USES:
Used as beverage
Burn it - as fossil fuels
Wear it - in perfumes
Wash with it – for cleaning
Dissolve in it - extracts
Slide40Production
of Rum
2
kinds
of
Rum
:
The
industrial
: the
alcohol
resulting
from
distillery
of molasses
The agricultural
:
alcohol obtained by distilling the fresh, fermented cane juice
Slide41PRODUCTION LINE
Slide42reaped
during the drying period
cut into short logs and bundled for transport crushed as soon as possible to avoid drying and deterioration of the sugar
THE CANE CUTTING
Slide43weighed, controlled and discharged.
millings stages: to separate the cane juice (vesou) from the fibbers (the
bagasse)The bagasse serves as combustion for the furnaces
The
vesou
is gathered in a drainage
system for filtering and pumped on
to the fermenting vats
CRUSHING
Slide44Process
of transforming the sugars into alcohol :
optimal temperature 30 C°yeast (private of oxygen) 72 hours after…Cane wine is obtained:
moût (7% of alcohol)Moût is quickly sent for distillation
THE FERMENTATION
Slide45THE DISTILLATION
Definition
: The method consist in heating the wine to vaporize the volatile components, mainly the alcohol, and then to condense them
The column give to the Rhum its own characteristics.
THE AGEING
White Agricultural Rhum
:
stored in huge wooden tuns to be "rounded out“ (before bottling)
Spring water is crossed to have the degrees desired for commercialisation (40° to 62°)
Golden agricultural Rhum or amber agricultural Rhum :
stored for at least 12 months in wooden containers.
golden colour: due to its short period spent in an oak tun
Slide47Other
distilleted beverages
Rakı
is an
unsweetened
,
anise-flavored
Turkish
alcoholic
drink
that
is
produced
by
grape
.
is an unsweetened, anise-flavored Turkish alcoholic
drin
k.
Brandy
is
a spirit produced by
distilling
wine
. Brandy generally contains 35–60% alcohol by
volum
e.
Gin
is a spirit which derives its predominant
flavour
from juniper
berries
(
Juniperus
communis
)
Vodka
is
a distilled
beverage
composed
primarily of water and
ethanol
,
sometimes with traces of impurities and flavorings. Traditionally, vodka is made by the distillation of
fermented
cereal grains
or
potatoes
,
though some modern brands use other substances, such as fruits or
sugar.
40
% alcohol by
volume
ABV
Slide48Production of vinegar
Slide49What is vinegar?
Vinegar is a product resulting from the conversion of alcohol to acetic acid by acetic acid bacteria,
Acetobacter spp.The name is derived from French (Vin = wine; Aigre-sour or sharp).
When alcoholic fermentation occurs and later during acidifications many other compounds are produced.Depending mostly on the nature of the material fermented and some of these find their way into vinegar.
Slide50Reactions also occur between these fermentation products
Ethyl acetate, for example, is formed from the reaction between acetic acid and ethanol.
It is these other compounds which give the various vinegars their organoleptic properties.The other compounds include:
non-volatile organic acids such as malic, citric, succinic and lactic acids; unfermented and unfermentable sugars; oxidized alcohol and acetaldelyde, acetoin, phosphate, chloride, and other ions.
Slide51Uses of vinegar
Ancient uses:
Food condiment
Treatment of WoundsWide variety of illnesses such as plague, ringworms, burns, lamenessCleansing agent
It was used as a cosmetic aid.
Slide52Modern uses:
Food condiment, sprinkled on certain foods such as fish at the table.(b) For pickling and preserving meats and vegetables; it can reduce the pH of food below that which even spore formers may not survive.
(c) Manufacture of sauces, salad dressings, mayonnaise, tomato productions, cheese dressings, mustard, and soft drinks.
Slide53TYPES OF VINEGAR
The composition and specifications of various types of vinegars are defined by regulations set up by the governments of different countries .
In the United States, for example, vinegar should not contain less than 4.0% (w/v) acetic acid and not more than 0.5% ethanol (v/v).
Slide54There are many different types of vinegars. The classification is usually based on the raw material used for its production. Malt vinegar, Wine vinegar, Apple cider vinegar, Balsamic vinegar, Fruit vinegar and many other types of vinegar exist in today’s global market. The most common types of vinegars and their origin are discussed
Slide55Wine
Vinegar
Wine vinegar is made from red or white wine and is the most commonly used vinegar in Mediterranean countries and Central Europe. As with wine, there is a considerable range in quality. Better quality wine vinegars are matured in wood for up to two years and exhibit a complex, mellow flavor. Wine vinegar tends to have a lower acidity than that of white or cider vinegars. Germany, Austria, and the Netherlands. Although its flavor depends on the particular type of beer from which it is made, it is often described as having a malty taste. That produced in Bavaria, is a light golden color with a very sharp and not-overly-complex flavor. In Beer vinegar and Wine vinegar production only one type of fermentation takes place; for the conversion of ethanol in to acetic acid
.Fruit vinegars are made from fruit wines, usually without any additional flavoring. Common flavors of fruit vinegar include apple, black currant, raspberry, quince, and tomato. Typically, the flavors of the original fruits remain in the final product. Most fruit vinegars are produced in Europe, where there is a growing market for high-priced vinegars made solely from specific fruits (as opposed to non-fruit vinegars which are infused with fruits or fruit flavors).
Beer
Vinegar
Fruit
Vinegars
Slide56Balsamic
Vinegar
Balsamic vinegar is an aromatic, aged type of vinegar traditionally crafted in the Modena and Reggio Emilia provinces of Italy from the concentrated juice, or must, of white grapes .It is very dark brown in color and its flavor is rich, sweet, and complex, with the finest grades being the product of years of aging in a successive number of casks made of various types of wood (including oak, mulberry, chestnut, cherry, juniper, ash, and acacia). Originally a product available only to the Italian upper classes, a cheaper form of balsamic vinegar became widely known and available around the world in the late twentieth century. True balsamic vinegar (which has Protected Designation of Origin) is aged for 12 to 25 years. Balsamic vinegars that have been aged for up to 100 years are available, though they are usually very expensive.
Malt vinegar is made by malting barley, causing the starch in the grain to turn to maltose. Then ale is brewed from the maltose and allowed to turn into vinegar, which is then aged. It is typically light brown in color.
Malt
Vinegar
Slide57Rice
VinegarRice vinegar is most popular in the cuisines of East and Southeast Asia. It is available in “white” (light yellow), red, and black varieties. The Japanese prefer light rice vinegar for the preparation of sushi rice and salad dressings. Red rice vinegar traditionally is colored with red yeast rice. Black rice vinegar (made with black glutinous rice) is most popular in China, and it is also widely used in other East Asian countries. White rice vinegar has a mild acidity and a somewhat “flat”,
uncomplex flavor.
Slide58ORGANISMS INVOLVED
The bacteria converting alcohol to acetic acid under natural conditions are film forming organisms on the surface of wine and beer.
The film was known as ‘mother of vinegar’ before its bacteriological nature became known.The bacteria were first described as
Mycoderma (viscous film) in 1822.Later other workers classified them in M. vini (forming film on wine) an M. acetic (forming film on beer).Pasteur confirmed that acetic acid is produced only in the presence of the bacteria, but he did not identify them.
The genus name
Acetobacter was put forward by Beijerinck in 1900.
Slide59Although
Acetobacter spp are responsible for vinegar production, pure cultures are hardly
used, except in submerged fermentation because of the difficulty of isolating and maintaining the organisms. The only member of the genus which is not useful, if not positively harmful in vinegar production is Acetobacter xylinum which tends to produce slime
Recently a new species, Acetobacter europaeus, was described. Its distinguishing features are its strong tolerance of acetic acid of 4 to 8% in agar, and its absolute requirement of acetic acid for growth.
Slide60Strains of acetic acid bacteria to be used in industrial production should:
a) tolerate high concentrations of acetic acid
b) require small amounts of nutrientc) not overoxidize the acetic acid formed
d) be high yielding in terms of the acetic acid produced.
Slide61The biochemical processes for vinegar production
Slide621 gm of alcohol should yield 1.304 gm of acetic acid but this is hardly achieved and only in unusual cases is a yield of 1.1 attained.
From the reactions one mole of ethanol will yield one mole of acetic acid and mole of water.
It can be calculated that 1 gallon of 12% alcohol will yield 1 gal. of 12.4% acetic acid.Over-oxidation can occur and it is undesirable.
In over-oxidation acetic acid is converted to CO2 and H2O. It occurs when there is a lack or low level of alcohol. It occurs more frequently in submerged fermentations than in the trickle processes.
Slide63Common production flowsheet of vinegar
Fruit juice
Fruits
Yeast
Alcohol Fermentation
Acetic Acid Fermentation
Ripening
Filtration
Pasterization
Bottling
Mother of vinegar
Slide64MANUFACTURE OF VINEGAR
Three methods used for the production of vinegar are :
The Orleans Method (also known as the slow method).The Trickling (or quick) Method
Submerged Fermentation.
Slide65The Orleans Method (also known as the slow method).
Slow process.
manufacture of high- quality vinegars.
also called continuous method.
T
his method, made famous by the French, was named after a small town in France named Orleans, known as the city of vinegars.
Slide661.The Orleans (or Slow) Method
The oldest method of vinegar production is the ‘let alone’ method in which wine left in open vats became converted to vinegar by acetic acid bacteria entering it from the atmosphere.
Later the wine was put in casks and left in the open field in the ‘fielding process’.A small amount of vinegar was introduced into a cask of wine to help initiate fermentation.
The introduced vinegar not only lowered the pH to the disadvantage of many other organisms but also introduced an inoculum of acetic acid bacteria.A thick film of acetic acid bacteria formed on the wine and converted it into vinegar in about five weeks.
Slide67The process had a number of disadvantages
(a) It was slow in comparison with later methods (slow method).
(b) It was inefficient, yielding 75-85% of the theoretical amount.(c) The ‘mother of vinegar’ usually gradually filled the cask and effectively killed the process.
Slide682 .The Trickling Generators (Quick) Method
The Dutch Boerhaave who in 1732 devised the first trickling generator in which he used branches of vines, and grape stems as packing.
Improvements were made by a number of other people from time to time.Later ventilation holes were drilled at the bottom of the generator and provided a mechanical means for the repeated distribution of the alcohol acetic acid mixture over the packing.
Slide69The heat generated by the exothermic reaction in the generator caused a draft which provided oxygen for the aerobic conversion of alcohol to acetic acid.
This latter model of the quick method (sometimes called the German method) enabled the production of vinegar in days instead of in weeks.
It remained in vogue unmodified for just over a century when several modifications were introduced in the Frings method, including: (a) forced aeration (b) temperature control
(c) semicontinuous operation.
Slide70The modern vinegar generator consists of a tank constructed usually of wood preferably of cypress and occasionally of stainless steel.
A false bottom supports the coils of birchwood shavings and separates them from the collection chamber which occupies about one fifth of the total capacity of the generator (Fig. 14.1).
A pump circulates the alcohol-acetic acid mixture from the reservoir through a heat exchanger to the top of the generator where a spray mechanism distributes it over the packing.Air is forced through the false bottom up through the set-up.
Slide71Slide72The cooling water in the heat exchanger is used to regulate the temperature in the generator so that it is between 29°C and 35°C; this is determined with thermometers placed at different levels of the generator.
The top of the generator is covered but provision exists for exhaust air to be let out.
Meters measure three parameters:(a) the circulation of the mash(b) the flow of cooling water through the heat exchange
(c) the amount of air delivered through the system.If the air flow rate is too high alcohol and vinegar are lost in effluent air.
Slide73Operation of the generator:
The trickling or circulating Frings generator is reasonably efficient, achieving, when operating maximally, an efficiency of 91-92% and it is capable of producing 500–1000 gallons of 100-grain (i.e. 10%) vinegar every 24 hours.
Although the wood shavings soften with age, well-maintained generators can proceed without much attention for twenty to thirty years.
They are easy to maintain once airflow and recirculation rates as well as temperatures are maintained at the required level. The level of ethyl alcohol must be maintained so that it does not fall below 0.3-0.5% at any time.
Slide74Complete exhaustion of the alcohol will lead to the death of the bacteria.
When wine and cider vinegar are made no nutrients need be added to the charge (i.e., the alcohol-containing material).
However, when white vinegar (produced from synthetic alcohol is used) nutrients e.g. simple low concentration sugar-mineral salts solution sometimes containing a little yeast extraction may be added.
Growth of the slime-forming Acetobacter xylinum is less with white vinegar (from pure alcohol) than with wine and cider vinegar.
Slide75Generators for producing white vinegar therefore become blocked by slime much less quickly than those used for wine and cider vinegar, and can last far in excess of 20 to 30 years before the wood shavings are changed.
The finished acidity of the vinegar is about 12%; when it is higher, production drops off.
In order not to exceed this level of acidity, when drawing off vinegar, the amount of alcohol in the replacement should be such that the total amount of alcohol is less than 5%.
videohttps://www.youtube.com/watch?v=ZZJSpTIoHH8
Slide763. Submerged Generators
The common feature in all submerged vinegar production is that the aeration must be very vigorous as shortage of oxygen because of the highly acid conditions of submerged production, would result in the death of the bacteria within 30 seconds.
Furthermore, because a lot of heat is released (over 30,000 calories are released per gallon of ethanol) an efficient cooling system must be provided. All submerged vinegar is turbid because of the high bacterial content and have to be filtered.
Some submerged generators will be discussed below.
Slide773.1 Frings acetator
Most of the world’s vinegar is now produced with this
fermentor.
It consists of a stainless steel tank fitted with internal cooling coils and a high-speed agitator fitted through the bottom. Air is sucked in through an air-meter located at the top. It is then finely dispersed by the agitator and distributed throughout the liquid.
Temperature is maintained at 30°C, although some strains can grow at a higher temperature.
Foaming is interrupted with an automatic foam breaker. Essentially it is shaped like the typical aerated stirred tank
Slide78Slide79It is operated batchwise and the cycle time for producing 12% vinegar is about 35 hours.
It is self aspirating, no compressed air being needed. The hollow rotor is installed on the shaft of a motor mounted under the fermentor, connected to an air suction pipe and surrounded by a stator.
It pumps liquid that enters the rotor from above outward through the channels of the stator that are formed by the wedges, thereby sucking air through the openings of the rotor and creating an air–liquid emulsion that is ejected outward at a given speed.This speed must be chosen adequately so that the turbulence of the stream causes a uniform distribution of the air over the whole cross section of the fermentor.
Slide80Slide81Advantages
(a) The efficiency of the acetator is much higher than that of the trickling generator; the production rate of the acetator may be 10-fold higher than a trickling unit.
Values of 94% and 85% of the theoretical have been recorded for both the acetator and the trickling filter.
(b) The quality is more uniform and the inexplicable variability in quality noted for the trickling generator is absent.(c) A much smaller space is occupied (about one-sixth) in comparison with the trickling generator.(d) It is easy and cheap to change from one type of vinegar to another.
(e) Continuous production and automation can take place more easily with Frings acetator than with trickling.
Slide82Disadvantages
(a) A risk exists of complete stoppage following death of bacteria from power failure even for a short time. Automatic stand-by generators have helped to solve this problem.
(b) It has a high rate of power consumption. Some authors have however argued that in fact in terms of power consumed per gallon of acetic produced the acetator is less power consuming.
Slide833.2 The cavitators
The cavitator was originally designed to treat sewage: it was then modified for vinegar production.
In many ways it resembled the acetator. However, the agitator was fixed to the top and finely dispersed air bubbles are introduced into the liquid. It operated on a continuous basis and was quite successful in producing cider and other vinegars as long as the grain strength was low.
It was not successful with high grain vinegar and the manufacture of the ‘cavitator’ was discontinued in 1969. Although some are still being used in Japan and the US.
Slide843.3 The tower fermentor
The tubular (tower) fermentor developed in the UK has been used on a commercial scale for the production of beer, vinegar, and citric acid.
The fermentor is two feet in diameter, about 20 feet tall in the tubular section with an expansion chamber of about four feet in diameter and six feet high.
It has a working volume of 3,000 liters and aeration is achieved by a stainless steel perforated plate covering the cross section of the tower and holding up the liquid. The charging wort is fed at the bottom. The unit can produce up to 1 million gallons (450,000 liters) of 5% acetic acid per annum. The system can be batch, semi or fully-continuous.
Slide85PROCESSING OF VINEGAR
(a)
Clarification and bottling: Irrespective of the method of manufacture, vinegar for retailing is clarified by careful filtration using a filter aid such as diatomaceous earth.
Vinegar from trickling generators are however less turbid than those from submerged fermentations because a high proportion of the bacterial population responsible for the acetification is held back on the shavings. After clarification it is pasteurized at 60-65°C for 30 minutes.
Slide86(b)
Concentration of vinegar:
Vinegar can be concentrated by freezing; thereafter the resulting slurry is centrifuged to separate the ice and produce the concentrate.With this method 200° grain (i.e., 20% w/v) acetic acid can be produced.
Concentration is necessitated by two considerations. One is the consequent reduction in transportation costs. The other is the need to prevent loss of activity of the vinegar when cucumbers were pickled in it after first being soaked in brine.
a grain (% acetic acid X 10)(analyzed by
volume)
1
grain
=64.79891
milligrams
Slide87FERMENTED VEGETABLES
Slide88FERMENTED VEGETABLES
Vegetable fermentation originated in the early years of human civilization and, even now, is widely used by many cultures.
Almost all vegetables can be fermented through natural processes because they harbor many types of lactic acid bacteria.Worldwide, most of the vegetable fermentation is done domestically.
The fermentation process for vegetables can result in nutritious foods that may be stored for extended periods, 1 year or more, without refrigeration. Examples of some fermented products and vegetables used currently for fermentation are sauerkraut and kimchi,(from cabbage), olives, cucumbers, carrots, celery, beans, peas, corn, okra, tomatoes, cauliflower, peppers, onions, citron, beets, turnips, radishes, chard, Brussels sprouts, and their blends.
Slide89SAUERKRAUT
Country: Germany
Major Ingredients: Cabbage, SaltUsage: Salad, Side DishProduct Description: Fermented shredded cabbage. The product has a sour taste with a clean acid flavor.Microorganisms: L. mesenteroides
, Lactobacillus brevis, Pediococcus cerevisiae and Lb. plantarum,Starter Culture: Natural Microflora, commercial starter cultures are available. Sometimes backslopping.
Slide90SAUERKRAUT
Slide91SAUERKRAUT
Salting
The level of salting is critical to obtaining a satisfactory product, it must be within the range 2–3% w/w and is normally about 2.25%. Too little salt (<2%) and the product softens unacceptably, too much salt (>3%) and the correct microbial sequence is not obtained.The salt serves a number of purposes:
(i) it extracts moisture from the shredded cabbage by osmosis to form the brine in which the fermentation will take place; (ii) it helps to inhibit some of the natural microflora of the cabbage such as pseudomonads which would otherwise cause spoilage and helps to select for the lactic acid bacteria; (iii) it helps maintain the crisp texture of the cabbage by withdrawing water and inhibiting endogenous pectolytic enzymes which cause the product to soften;
(
iv) finally, salt contributes to the
flavour
of the product.
Slide92SAUERKRAUT
Fermentation
The starter for sauerkraut production is usually the normal mixed flora of cabbage.The raw material has a large number of undesirable organisms and a small population of lactic acid bacteria (<1%)Among the lactic acid bacteria, most are Lactococcus spp. and Leuconostoc
spp., and a small fraction is Lactobacillus spp. and Pediococcus spp. During fermentation, sequential growth of these lactic acid bacteria occurs. The presence of 2.25% salt, large amounts of fermentable sugars (sucrose, hexoses, pentoses), an absence of oxygen, and a low fermentation temperature facilitate Leuconostoc spp., primarily
Leu
.
mesenteroides
, to grow rapidly
Slide93SAUERKRAUT
Fermentation
When the acidity has reached approximately 1% (as lactic acid), growth of Leu. mesenteroides slows down. Then Lab. brevis starts growing rapidly until acid production reaches approximately 1.5%. Then
Ped. pentosaceus takes over and increases the acidity to approximately 1.8%. Finally, Lab. plantarum starts growing and brings the acid level to approximately 2%.
Slide94SAUERKRAUT
Biochemistry
Leuconostoc spp. metabolize sucrose, hexoses, and some pentoses in the raw material to lactate, acetate, ethanol, CO2, and diacetyl. Lab. brevis (obligatory heterofermentative, such as Leuconostoc
spp.) ferments sucrose, hexoses, and pentoses to products similar to those by Leuconostoc spp. Ped. pentosaceus metabolizes hexoses to form mainly lactic acid and some pentoses to lactic acid, acetate, and ethanol.
Lab.
plantarum
also produces products from sucrose, hexoses, and
pentoses
similar to those by Ped.
pentosaceus
.
The characteristic flavor of sauerkraut is the result of the combined effects of lactate, acetate, ethanol, CO2, and diacetyl in proper amounts.
Slide95KIMCHI
Region
: KoreaMajor Ingredients: Chinese Cabbage, Asian Radish, Red Pepper, Ginger, Garlic, SaltUsage: Salad, Side DishProduct Description: Fermented shredded cabbage. The product has a sour taste with a clean acid flavor.
Microorganisms: L. mesenteroides, Lactobacillus brevis, Pediococcus cerevisiae and Lb. plantarum,Starter Culture: Natural Microflora, commercial starter cultures are available.
Slide96KIMCHI
Slide97KIMCHI
Slide98KIMCHI
Biochemistry and fermentation aspects of Kimchi are similar to sauerkraut.
The best taste is claimed after 3 days at 20C when the acidity is 0.6% and the pH around 4.2. Leuconostoc mesenteroides is the principal organism responsible for the fermentation D
ominance of Lactobacillus plantarum is regarded as a defect which results in an excessively sour product.
Slide99DIFFERENCE BETWEEN KIMCHI AND SAUERKRAUT
Sauerkraut
ParameterKimchi
2%Acid content0.6%2-3%
Salt Content
3-3.5%
Min 7 days
Fermentation Time
3-4
days
Only Cabbage and Salt
Ingredients
Contains added ingredients for flavor
Finely ShreddedCabbageLarge Chunks
Slide100OLIVES
Region
: MediterraneanMajor Ingredients: Olives, BrineUsage: Salad, Side DishMicroorganisms: L.mesenteroides, Lactobacillus brevis,
Pediococcus cerevisiae and Lb. plantarum,Starter Culture: Natural Microflora, commercial starter cultures are available.
Slide101OLIVES
Slide102OLIVES
Fermentation
The initial pH of the fermentation can be above 7 depending on how much washing was done after the NaOH treatment. As a consequence, the initial microflora during fermentation can include a variety of gram-positive bacilli (Bacillus species) and gram-negative enteric bacteria (Enterobacter, Citrobacter,
Klebsiella, and Escherichia). As organic acids accumulate and the pH decreases below 6, the LAB, principally Lb. plantarum, dominate the fermentation to the exclusion of the other gram-positive and gram-negative microbes. Yeast species may also be present (Candida, Pichia, Saccharomyces, and others) and
contribute desirable flavor characteristics to the brined olives.
Slide103PICKLES
Region
: North America, GermanyMajor Ingredients: Cucumber, Spices, Dill etcUsage: Salad, Side DishMicroorganisms:
Lactobacillus brevis, Pediococcus cerevisiae and Lb. plantarum,Starter Culture: Natural Microflora, commercial starter cultures are available. Sometimes backslopping.
Slide104PICKLES
Slide105Definition:
“It is the process of preserving food by anaerobic fermentation in brine to produce lactic acid, or marinating and storing it in an acid solution, usually vinegar (acetic acid). The resulting food is called a PICKLE”.
The term pickle is derived from the Dutch word pekel
, Canada, the word pickle alone almost always refers to a pickled cucumber. Other types of pickles will be described as "pickled onion," "pickled cauliflower," etc.
Slide106SALIENT FEATURES:
Brining or Corning.
Food salty or sour taste. PH less than 4.6.
Preserve perishable foods Antimicrobial herbs and spices.
Slide107Pickling Equipment:
Utensils made of zinc, iron, brass, copper, or galvanized metal should not be used.
For fresh-pack pickling large container made of stainless steel, glassware.For fermenting and brining, a crock or stone jar, an un chipped enamel-lined pan, a glass jar, a bowl, used for small quantities.
Slide108Pickles with Salt Content:
Fresh-pack pickles may be prepared safely with reduced or no salt; they are acidified quickly with vinegar.
salt used in making brine pickles and fermented sauerkraut .The function of salt in fermented foods is to encourage the growth of desirable bacteria
Slide109Key ingredients in
pickling
I
ngredient
Why used???
Salt
Acts as a preservative by encouraging the growth of desirable bacteria (and inhibiting undesirable bacteria) which in turn produce lactic acid, a preservative.
Helps draw juices and sugar from the produce to make a brine.
Adds flavor and crispness.
Vinegar
Gives pickles a tart taste.
Acts as a preservative due to the acidity of vinegar.
Slide110Sugar
Sweetens taste; counteracts vinegar.
Spices/Herbs
Adds flavor
Water
Makes liquid portion of brine.
Alum
Improves pickle firmness for fermented pickles; does not
improved
firmness of quick-process pickles.
Lime
Improves pickle firmness.
Slide111Trouble-shooting pickles
NOTE: These pickles are safe to eat even though they may not look
too good.
This happened:
Because of this:
Shriveled pickles
Vinegar or salt solution too strong.
Overcooking or over processing.
Hollow pickles
Poory
developed cucumbers.
Cucumbers too ripe.
Cucumbers held too long before pickling.
Fermentation too rapid.
Slide112SHALGAM
Shalgam
is a traditional Turkish fermented beverage in which mainly lactic acid bacteria play an important role. It is a red colored, turbid and sour soft beverage produced by mixing of turnip, purple carrot, sourdough, salt, water and fermenting for 10-12 days. Red beet can also be used as a raw-material.
Slide113Microorganisms
The microorganisms influenced in the fermentation obtained from sourdough. These are L.
sanfranciscensis, L. pontis, L. brevis, L. plantarum, L. alimentarius,L. fructivorans, L. reuteri
, L. fermentum and Saccharomyces cerevisiae and to less extent Saccharomyces exiguous, Candida krusei and Candida milleri.
Slide114Definition
and production
According to the Turkish Standards Institution, shalgam is defined as a beverage produced by lactic acid fermentation of black carrot (Daucus carota L.), turnip (Brassica rapa L.), salt and extract of sourdough and bulgur flour. For
shalgam production, no standard manufacturing technique is available and many different methods can be used in production.
Slide115Production
Production