BEENISH GILANI SHARMEEN RAFIQUE MARIA IQBAL ALI RAZA.
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Transcript of BEENISH GILANI SHARMEEN RAFIQUE MARIA IQBAL ALI RAZA.
FOOD & BEVERAGE FERMENTATIONS
GROUP MEMBERS
BEENISH GILANI SHARMEEN RAFIQUE MARIA IQBAL ALI RAZA
FOOD & DAIRY PRODUCTS
Important for living organisms. Provide energy Can be obtain from plants, animals and
microorganisms
TRADITIONALN FERMENTED FOODSTUFFS
ALCOHOLIC BEVERAGES: beers, wines, distilled spirits derived from sugars and starches. DAIRY PRODCTS: cheese, yoghurt, sour cream and kefir. FAT & MEAT PRODUCTS: fish sauce and fermented sausages. PLANT PRODUCTS: cereal based breads, fermented rice products, fermented fruits, vegetables, legumes, olives, soya sauce, coffee beans.
Products orignally evolved as means of food presevations.
Stabilize microbial activity Microbial biomass as noval food e.g
mashrooms Microbial enzymes use as food
processing aids.
ALCOHOLIC BEVERAGES
Produced throughout recorded human history
Manufacture worldwide by sugars derived from fruit juices, plat sap, honey.
Drunk freshly Aged to modify their flavour Distilled to increase alcoholic strength
BACTERIA INVOLVED IN PRODUCTION
Zymomonas species ?????? Saccharomyces cerevsiae
BEER BREWING
Non-distilled alcoholic beverges Partially germinated cereal grains Includes ales, lagers, stouts, 3-8%
ethanol Hops for flavour and aroma Water yeast
BREWING PROCESS
4 main stages: MALTING MASHING & WORT PREPERATION YEAST FERMENTATION (prepared
but not ready to use) POST-FERMENTATION*
MALTING
Partial germination of barley grains Modify hard vitreous grains into friable
with more degradable starch & hydrolytic enzymes
Sock barley in water for 2 days at 10-16°C
Increase moisture 45% Water drained out Aeration*
After steeping barley partially germinated for 3-5 days at 16-19°C
Spread grains on malting floor Airated with moist cool air
WORT PREPERATION
Production of aqueous fermentation media.
Extraction of fermentable sugars, amino acids, vitamins from malt.
Aducants are also added. Roller-milled prior
MASHING
Starch hydrolysis Malt & adjunct starch to fermentable sugars. Malt enzymes degrades starch: β-Glucan
hydrolysis, Protein hydrolysis. Mashing system: 1. infusion mashing 2. decoction mashing 3. temperature programmed mashing (modern)
YEAST FERMENTATION
S. cerevisiae as starter culture Selected on the basis of performance in
brewery enviornment. Polypoid and more stable Undergoes alcoholic fermentation Ethanol, CO2, minor metobolites. Last for 2-7 days.
POST FERMENTATION
Maturation of beer Condition for consumption1. CASK AND BOTTLE CONDITIONONG OF
ALES2. KRAUENING3. LAGERING4. STORAGE AGEING5. PREVENTION OF OXIDATION
WINE PRODUCTION
Plant extract or fruit juice that contains sufficient levels of fermentable sugars.
Berries of the grape vine, primarily cultivars of Vitis vinifera, which can be grown in most temperate regions of the world.
Total world production is now approximately 1010L/annum
GRAPE JUICE
wine production because it contains high levels of fermentable sugars (mainly glucose and fructose; 160–240 g/L),
The natural acidity (pH 2.8–3.8) inhibits potential spoilage organisms
Grapes also have very pleasant flavour and aroma components.
Most wines are table wines that normally contain up to
14% (v/v) ethanol. However, some regions produce wines fortified with ethanol,
FACTORS THAT INFLUENCE THE PROPERTIES OF A WINE.
1 The specific grape variety or mixture used (e.g. Muscat grapes contain highly characteristic flavour and aroma components, the terpene alcohols linalool.2 The soil, local climate and the mode of grapecultivation3 Grape maturity and condition at harvest4 The methods of grape pressing and processing
FACTORS THAT INFLUENCE THE PROPERTIES OF A WINE.
5 The primary fermentation, which generates variablequantities of ethanol, CO2, higher alcohols, esters,aldehydes and ketones
6 Any secondary fermentation to produce winecarbonation, or for acidity reduction via a malo-lacticfermentation, whereby malic acid is converted to lacticAcid
7 post-fermentation and maturation treatments.
PRODUCTION OF GRAPE MUST
Mechanical destemming, crushing and pressing to form the must
Red wine must consists of the macerated fruit, whereas for white wines it is only the clarified juice that is fermented.
Carbonic maceration, White wine earlier removal of skin and
seeds
WINE FERMENTATION
Alcoholic fermentation of wine is carried out by indigenous yeast or added starter yeast.
The fermentation rate is influenced by:1 the starter yeast strain used or yeast strains thatmake up the natural microflora;2 temperature;3 pH;4 initial sugar concentration; and5 nutritional components of the batch of grape or supplement.
TRADITIONAL SPONTANEOUS WINE FERMENTATIONS
Once the juice is released from the grapes it will ferment spontaneously as it is immediately exposed to the natural indigenous microflora.
Traditional fermentations are comparatively slow They can also be prone to some flavour and aroma defects due to the overactivity of certain yeasts.
To ensure complete fermentation, and avoid production of unwanted flavour and aroma compounds, winemakers encourage the growth and dominance of S. cerevisiae.
This may be achieved by adding SO2 to the grape must at a concentration of 30–50 mg/L, which inhibits non- Saccharomyces yeast and spoilage bacteria.
USE OF STARTER CULTURES
Newer wine-producing regions have less well developed natural microflora. Therefore, added starter cultures are normally used.
Use of starter cultures provides several advantages: it ensures
completion of the fermentation and allows the fermentation rate to be controlled, to give a shorter lag period, and more even and rapid fermentation rates. Also, there is less opportunity for the production of off-flavours by
wild yeasts and bacteria, giving more consistent flavour characteristics and quality.
SECONDARY WINE FERMENTATION
Such secondary fermentations include a yeast alcoholic fermentation in bottles or cask to create naturally carbonated sparkling wines.
Malo-Lactic acid fermentation takes place,
It reduces the acidity through the decarboxylation
POST FERMENTATION TREATMENT
A small amount of SO2 is added to prevent microbial activity.
Some wine is stored for a period of a few weeks to several years in wooden casks, where it acquires additional flavour characters.
wine is filtered, pasteurized or sterile filtered, and filled into bottles or other packages
VINEGAR
when a natural solution of fermentable sugars is exposed to indigenous microbial activities is an alcoholic fermentation by yeasts, followed by bacterial oxidation of the ethanol to acetic acid (acetification). If sufficient acetic acid is produced it may be classified as vinegar.
It is produced from fermentable substrates and alcoholic beverages and fruit juices and sugar syrups, molasses and honey, root starch.
VINEGAR FERMENTATION
Alcoholic fermentation: This is an anaerobic process performed by specific
vinegar-making strains of yeast, usually S. cerevisiae var. ellipsoideus, Fermentation products are ethanol, CO2, and small amounts of glycerol, acetic acid and some higher alcohols.
Acetic acid fermentation: The acetic acid fermentation is a highly aerobic
process, essentially a biotransformation by acetic acid bacteria, involving incomplete oxidation of ethanol to acetic acid
METHODS OF ACETIFICATION IN VINEGAR MANUFACTURE
Conversion of alcohol to acetic acid is largely a problem of aeration technology, There are three main techniques that can be used to achieve this
1 Traditional surface method: These traditional batch methods are
generally slow and unpredictable
METHODS OF ACETIFICATION IN VINEGAR MANUFACTURE
TRICKLING GENERATORS: These methods involve the movement of alcoholic liquid over surfaces on which films of acetic acid bacteria have become attached (a supported film system), and a good air supply is provided to facilitate ethanol oxidation.
SUBMERGED METHODS
Submerged methods are five times faster than the trickling methods and require less capital investment. Since their introduction
Improved aeration efficiency, based on Frings acetators, consists of a highly aerated stainless steel stirred tank reactor. This vessel is continuously stirred at 1450–1750 r.p.m.
Submerged processes are usually operated automatically on a semicontinuous basis.
FINISHING PROCESS
Some vinegars may be decolorized using potassium ferrocyanide
pasteurized at 75–80°C for 30–40 s prior to bottling.
Recovery of acetic acid can be achieved solvent extraction methods.
DAIRY FERMENTATIONS
DAIRY FERMENTATIONS
DAIRY FERMENTATIONS
More recently popularized dairy products include fermented health drinks and foods,reffered to as probiotics.
e.g Lactobacillus acidophilus
Use of pasteurized milk not only reduces the possibility of growth of potential pathogens .
Also lowers the activity of certain milk enzymes that can affect some dairy fermentations.
Fermentation generates lactic acid,which modifies milk proteins,and forms flavor.e.g diacetyl,which imparts a buttery flover.
BUTTER PRODUCTION
STEPS
Milk Cream Legal pasteurization Aging Ripening Churning Draining buttermilk Washing
Working Pakaging Storage Butter
YOUGERT PRODUCTION
VIDIO
http://www.youtube.com/watch?v=cvxTaCNP66w
FERMENTED PLANTS
PRODUCTS
ALI RAZA ANSER
Fruits Cereals Leaf and root vegitable Legumes OilseedsThese are all used for the
production of fermented foods.
Why fermentation?
Improve digestibility Nutritional value Texture Flavour
DETAILED DISCUSSION
Bread Sauerkraut Production Soya Bean Fermentation Coffee Cocoa Tea
BREAD PRODUCTION
A History of 4000 Years Yeast Purpose: Generate Carbon dioxide Add flavor, alcohol, acid, chemical
modified Gluten to promote the expansion of dough.
Wheat and several related cereal grains are used.
Contain Gluten protein. Gluten Function Final flavor of the bread Dough making Elastic properties to the dough
Dough trap CO2 and rise in volume Baking Bread protein is denatured and along
with starch it forms the open crumb texture.
Bread dough contains more than 20% rye flour which must be acidified to produce acceptable bread.
Amylase Activity stops (Acidification).
Acidification can be done by adding citric acid or by sour dough fermentation.
SAUERKRAUT PRODUCTION
Wilted shredded Cabbage Mix with 2-3% salt to reduce the
activity of water Inhibition of Gram negative bacteria. Starter culture of lactic cid bacteria are
added (Lactobacillus plantarum, Lactobacillus brevis, Leuconostoc mesenteroids).
Fermentation occurs and lasts for 20-30 days at 18-20 C.
Final lactic acid levels reach 1.5% v/v.
Moderen commercial fermentation
Fiber glass or concrete tanks are used Capacity 100 tones.
Traditional process
Natural Micro flora is used. E.g. Sauerkraut
SOYA BEAN FERMENTATION
Substituted for dairy fermented products in South east Asia.
Different products like Miso Tempeh Soya sauces
Involves the fermentation of cooked whole or dehulled soya beans by Rhizopus species.
soy sauce are used as colouring agents and flavouring as well.
Manufacturing involves three different stages. Koji
it is solid substrate, aerobic fermentation of cooked soya beans.
It is also made by steamed defatted soya flakes, with addition of rice and wheat flour.
The temperature is 25-30 Celsius and it is processed in 2-3 days.
Moromi It involves the fermentation of the liquid slurry and it
is anaerobic fermentation that results from the fermentation of brine to koji.
The activity of microbe acidify and prevent spoilage.. Along with this they perform alcoholic fermentation
and produce additional flavour compounds. The product is traditionally made in 6-9 months.
COFFEE, COCOA AND TEA FERMENTATION
Coffee Bean is either obtain by dry or wet
process. Wet gives better beans. It involves better action of indigenous
bacteria and filamentous fungi. The pulpy material that surrounds the
bean is removed by the action of enzymes.
Then it is subjected to lactic acid fermentation.
COCOA
Has same microbial activity as coffee. But this is more important
comparatively. At first we observe alcoholic
fermentation. Followed by activity of lactic acid
bacteria. Finally acetic acid bacteria does its
duty and converts it into alcohol and acetic acid.
TEA
No action of micro organisms is there. Action of enzymes are involved. Breaks the leaves and eliminate
moisture content. To give a dry product that we refer to
as tea.
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