BREWERIESBREWERIES

• Place dedicated to make beer• Diversity of breweries is based on

-diversity of processes

- degrees of automation

-kinds of beer produced• Oldest brewery – Weinhnstephan brewery in

Bavaria, Germany.

INDUSTRIALIZATION OF BREWERY

INDUSTRIALIZATION OF BREWERY

• Can be traced back to almost 5,000 years to Mesopotamian writings

• Production of beer took place at home- “women’s work”.

• Monasteries and other Christian institutions used beer as payment.

• Early breweries were built on multiple stories• Used large copper vats• Fermentation and packaging in lined wooden

containers.

MAJOR TECHNOLOGICAL ADVANCES

MAJOR TECHNOLOGICAL ADVANCES

• The steam engine by James Watt brought automatic stirring mechanisms and pumps into the brewery.

• Carl Von Linde is credited with developing the refrigeration machine .

• The discovery of microbes by Louis Pasteur was instrumental in controlling the fermentation process.

MODERN BREWERYMODERN BREWERY

• Vessels- stainless steel

• Heating – pressurized steam, direct- fire systems

• Cooling- jackets

• Samples are pulled out at every step of the process.

BEERBEER

• World’s most widely consumed alcoholic beverage• Third most popular drink overall after water and tea• The “code of Hammurabi” included laws regulating beer

and beer products• “the Hymn to Ninkasi” – a prayer to the Mesopotamian

Goddess of beer• Today brewing is a global business that includes several

multinational companies• Strength of beer is usually around 4 to 6% although it

may vary from 0.5 % to 40 %

BREWINGBREWING

• Process of making beer• Starch source wort beer• effected by yeast

INGREDIENTSINGREDIENTS

• Water• Starch source, such as

malted barley• Brewer’s yeast• Hops ( for flavoring)

MATLED BARLEY BEFORE ROASTING

Less commonly used starch sources include

• Millet, sorghum and cassava root in Africa• Potato in Brazil• Agave in Mexico

WATERWATER

• Beer is composed mostly of water• Different mineral compositions of water- different

types of beer• Dublin has hard water, well suited to make stout

like Guinness• Waters of Burton in England contain Gypsum

which benefits making pale ale.

STARCH SOURCESTARCH SOURCE

• Fermentable material• Key source in determining the strength and

flavor of beer• Malted grain – most common source

GRAIN IS SOAKED IN WATER

DRYING PARTIALLY GERMINATED

GRAIN IN A KILN

• Malting grain produces enzymes that convert starch into fermentable sugars

• Different roasting time and temperature are used to create different colors of malt from the same grain

• Darker malts produce darker beers.

HOPSHOPS

• Flavoring beer• Flowers from hop vine

are used as flavoring and preservative agent

• Flowers are called hops

HOP CONE

CHARACTERISTICS OF HOPSCHARACTERISTICS OF HOPS

• Contributes bitterness to the beer, that balances the sweetness of malt

• Contribute floral, citrus and herbal aromas and flavor to the beer

• Have an antibiotic effect- useful in fermentation process

• Aids in “head” retention• The acidity of hops is a preservative.

YEASTYEAST

• Brewer’s yeast- Saccharomyces cerevisea(top

fermentor)

Saccharomyces uvarum( bottom

fermentor)• Responsible for fermentation in beer• Metabolize the sugars extracted from grains into

alcohol and CO₂.• also influence character and flavor of beer

BREWING PROCESSBREWING PROCESS

9 steps: • Malting• Milling• Mashing• Lautering• Boiling• Fermenting• Conditioning• Filtering• Filling

ROYAL BREWERY IN MANCHESTER, UK

MASHINGMASHING

• Combining malted barley and water and heating in a “mash tun”

• Allows enzymes in the malt to convert complex sugars into maltose

• Usually takes 1 to 2 hours• The end product of

mashing is called “wort”.

• Mashing involves pauses at certain temperatures

-45˚C –activates various proteases

-62˚C –activates β- glucanase

-73˚C-used to convert starches in the malt to sugar.

LAUTERINGLAUTERING

• Separation of wort from the grains• Carried out in a lauter tun• Tank with holes at the bottom small enough to

hold back the large bits of hulls. • Two stages:

1. wort run off

2. sparging

BOILINGBOILING

• Beer wort is boiled with hops in “copper” or brew kettles

• Chemical reactions

-releasing of hop flavors

-sterilization of wort

-precipitation of proteins

-stopping enzymatic reactions

-concentration of wort

BREW KETTLES

WHIRLPOOLINGWHIRLPOOLING

• Tea-leaf paradox forces denser solids ( coagulated proteins, vegetable matter from hops) into a cone in the centre of the tank.

• There is a separate tank for whirl pooling

WORT COOLINGWORT COOLING

• After whirl pooling, the wort is brought down to fermentation temperature before yeast is added

• 20 to 26˚C• Plate heat exchanger

FERMENTATIONFERMENTATION

• Chemical conversion of sugars into alcohol

• Wort is cooled and aerated with sterile air

• Yeast is added to it and fermentation begins.

• Cyclo-cylindrical vessels or CCVs are used

• Cone’s aperture is 60˚• Made of stainless steel

• Brewing yeasts may be classified as

- top fermenting ( S. cervisea)

- bottom fermenting (S. uvarum)• Top fermenting yeasts- form a foam on top of the

wort during fermentation• Higher alcohol content• Higher temperature (16 to 24˚C)• Fruitier and sweeter beers.

• Bottom fermenting yeasts

- cool fermented, lager type beers

-ferment more sugars

- dry beer

-grow well at low temperature ( 10 to 18 ˚C)

- Ex. Saccharomyces pastorianus, formerly known as Saccharomyces carlsbergensis

CONDITIONINGCONDITIONING

• Maturing or aging• 2 to 4 weeks, several months or years

depending on the type of beer• Beer is transferred to a second container so that

it is no longer exposed to yeast.

Krausening:• Fermenting wort is added to the finished beer• The active yeast will restart fermentation• Introduce fresh CO₂• Conditioning tanks are sealed so that CO₂ will

dissolve in the beer• May be used to condition bottle beer

Lagering:• Lagers are aged at near freezing temperatures

for 1 to 6 months• Serves to reduce sulphur compounds produced

by bottom- fermenters• Produces a cleaner tasting final product with

fewer esters.

FILTRATIONFILTRATION

• Stabilizes flavor• Gives beer its polished shine and brilliance• Diatomaceous earth powder• Filtration ratings:

- rough : leaves some cloudiness in the beer

-fine : removes all cloudiness

-sterile : removes microorganisms

PACKAGINGPACKAGING

• Glass bottles• Aluminum cans• Kegs

NUTRITIONAL INFORMATIONNUTRITIONAL INFORMATION

1 can (350 ml) of beer contains:• Calories :153• Fat(g): 0• Carbohydrates(g): 12.64• Fibers(g): 0• Protein(g): 1.64• Cholesterol(mg): 0

HEALTH EFFECTSHEALTH EFFECTS

• Brewer’s yeast is a rich source of nutrients• Beer contains significant amount of magnesium,

selenium, phosphorous,potassium, biotin, chromium and B vitamins

• Low alcohol beer has anti cancer properties• Non alcoholic beer has cardiovascular benefits.