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Acknowledgement

I wish to express my deep sense of gratitude to Mr. Hardeep Singh, Human Resources

Manager, United Breweries, Ludhiana.

I would like to thank Mr. E. Jacob, Head Brewer, who had been a source of inspiration and

for his timely guidance in the conduct of my project work. I would also like to thank

Mr. Vanish, Chief Engineer, Brew Section for all his valuable assistance in the project work.

Words are inadequate in offering my thanks to United Breweries, Ludhiana for giving me this

opportunity to do my summer training with the esteemed organization. It truly was a great

learning experience.

Finally, yet importantly, I would like to express my heartfelt thanks to Dr. Abhijit Ganguli,

Department of Biotechnology, Thapar University, Patiala for his help in the successful

completion of this project.


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Declaration

I hereby declare that the project work entitled BEER MAKING PROCESS is an authentic

record of my own work carried out at UNITED BREWERIES LIMITED, LUDHIANA as

a requirement of six week training for the award of the degree of B.Tech. (Biotechnology),

Thapar University, Patiala. This work has been done under the supervision and guidance of

Mr. E. Jacob, Head Brewer during the training programme from 6 June 2010 to 16 July 2010.

Gautam Sood

700800015

B Tech. Biotechnology

Thapar University

Patiala


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Contents

Topics

1. ACKNOWLEDGMENT2. CERTIFICATE3. DECLARATION4. INTRODUCTION SIX WEEK TRAINING THE UNITED BREWERIES

GROUP

COMPANY PROFILE5. MATERIALS USED6. THE INDUSTRIAL PROCESS MALTING MILLING RICE COOKER MASHING LAUTERING WORT BOILING WHIRLPOOL WORT COOLING AERATION FERMENTATION MATURATION CLEANING IN PROCESS FILTRATION CARBONATION BRIGHT BEER TANK BOTTLING7. ANCILLARY OPERATIONS8. REFERENCES9. APPENDIX

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Introduction

The Six Week Industrial Training

The Six Week Industrial Training is a compulsory course which every student has to undergo

during his summer vacations after the completion of 4 th semester. The main aim of industrial

training is to understand the working culture of the industry. The students should be able to

co-relate the theoretical knowledge imparted to them in the classroom with the practical

aspects of the industry. The students should understand the problems of the industry and try

to find out their solutions. This will not only enhance their knowledge, but also help them in

all-round development.

In United Breweries Limited, Ludhiana I think, I tried to fulfil the aims and objectives of the

six week industrial training to the best of my capabilities.

The United Breweries Group

Before discussing about the descriptive information of the process

taking place in the industry, let me share some details of the industry.

The United Breweries Group is a multi-faceted conglomerate with

business interests in

Beverage Alcohol International Trading Research & Development Aviation Pharmaceuticals Fertilizer

Media

Brief History: The UB Group was founded by a Scottish gentleman Thomas Leishman in

1915. The company used to manufacture beer at that time. In August 1947, Vittal Mallya

became the company's first Indian director. United Breweries came into limelight by

manufacturing bulk beer for the British troops. Kingfisher, the Group's most visible and

profitable brand, made its entry in the sixties. Thereafter, the Group moved into agro-based

industries and medicines.


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Vijay Mallya assumed the mantle of the group in 1983. In 1988, UB Group acquired the

global Berger Paints Group with operating companies across four continents. The paints

business was divested for significant value in 1996. UB Group is the third largest

manufacturer of Spirits products in the world. In 2005, the Group entered aviation sector with

the launch of Kingfisher Airlines Limited. Within a short time the airlines has captured animpressive market share and has established a niche identity for itself.

Company Profile

United Breweries Limited

C -60, Phase - VI, Focal Point, Industrial Area, Ludhiana

141001.

General Manager: Mr. Ajay Jairath

The plant was initially owned and run by the government and known by the name of Punjab

Breweries Ltd. It became a sick unit and was taken over by the U.B. group. UBL, Ludhiana is

a kingfisher beer manufacturing plant. It makes upto 8 - 8.5 lakh beer cases per month duringthe peak season i.e. March to June. But during winter season, beer consumption reduces so

the manufacturing of beer cases reduces to 3 - 4 lakh cases per month. Only the glass bottles

are manufactured here, no cans. The production rate per day is 3 - 4 lakh bottles. The

Brewery mainly supplies beer to Punjab, Delhi, Haryana, Jammu and Kashmir and

Chandigarh.

The brewery produces only two brands:

Kingfisher Strong Kingfisher Light

Soon the company is going to launch new beer called Dark Kingfisher Red Beer, targeted for

winter market. Kingfisher has 55% share of market in beer.


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UBL, Ludhiana is a perfect example of modern industry. Every single process of beer making

is computerized. A single person can operate the whole plant sitting in his office. The labour

work has reduced to great extent. Due to introduction of new technology, it is able to fulfil its

desired goal within time limits and with desired efficiency. Apart from earning profits, the

company also devotes time to work for social cause. They understand the importance ofCorporate Social Responsibility. They also carry out tree plantation programmes and

environment cleanliness drives. They have their own water treatment plant and carbon

dioxide recovery plant so that foul and impure water and carbon dioxide does not affect the

environment and people living around.

Major Materials Used For Brewing Process


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The basic ingredients of beer are

Water Maltbarley and rice Hops Yeast

Although the main ingredients of beer have remained constant, it is the precise recipe and

timing of the brew that gives one a different taste from another. The production of beer is one

of the most closely supervised and controlled manufacturing processes in our society.

Other materials used at various stages of process are:

Gypsum Whirlfloc Calcium chloride Glycol Promalt Sugar Termamyl

The major beer making process of United Breweries Limited, Ludhiana (Kingfisher)

proceeds as follow:

Malting Milling Rice Cooker Mashing Lautering Wort Boiling Whirlpool Wort Cooling Fermentation Lagering Filtration Packaging


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Malting

Malted barley is supplied to this Kingfisher plant from Patiala.

Malt is a term that is used for cereal grains that undergoes the malting process. Different

grains have different yields and flavours. Brewers may use a single or a combination of

grains, depending on their requirements. Around the world, barley, wheat, rice, corn, maize,

rye, oats and sorghum are used

Malting is a process applied to cereal grains converting their insoluble starch to soluble

starch, reducing complex proteins, generating nutrients for yeast development, and the

development of enzymes.

In more technical terms, the malting process stimulates the production of enzymes (alpha

amylase and beta amylase) within the seed that soften its outer walls or husks and modifies its

starches into a more soluble mass.

What Does a Brewer Really Want From Malt?

A good source of fermentable sugars the main purpose for the wort produced frommalt is for yeast to ferment it to alcohol.

A source of enzymes these are critical in the brew house to break down the largermacromolecules to nutrients that the yeast may utilize in fermentation.

Macro- and micronutrients for fermentation many are already present in the maltedbarley and merely need dissolving in the brew house.

No processing problems as we shall see, poorly manufactured malt may give thebrewer many processing problems.

Stable beer with good shelf-lifeas well as processing problems poor quality malt mayalso lead to a beer with negative properties such as haze and poor foam.
http://en.wikipedia.org/wiki/Cerealhttp://en.wikipedia.org/wiki/Cerealhttp://en.wikipedia.org/wiki/Cereal


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Why most often barley is used?

Barley is particularly well suited to the brewing task because of following reasons:

A barley seed has three outer protective layers - husk, pericarp and testa. This protectsthe seed through the stages of harvest, storage and malting.

The honeycomb microscopic shape of the husk makes for agood natural filter bed that is used to separate the wort or

brewing liquid from the mash.

It has an insanely high starch yield, being 90 per centcarbohydrate 80-85% of which is the grains food cell,

exactly what the brewer is after.

When it has germinated or is green malt, it is extremelyhardy and does not easily separate from its huskkeeping

it intact for the brewer. It will only gelatinise at relatively low temperatures and therefore is less likely to clog up

brewing vessels.

It has high diastatic powerorenzymecontent.

The three main steps of the malting process are:

Steeping Germination Drying

Barley steeping

The purpose of steeping is to evenly hydrate the endosperm mass and to allow uniform

growth during germination. Steeping begins by mixing the barley kernels with water to raise

the moisture level and activate the metabolic processes of the dormant kernel. The water is

drained and the moist grains are turned several times during steeping to increase oxygen

uptake by the respiring barley.

Steeping has two major functions

Raise the moisture content from 12% in different steps to 40% to initiate germination.The increase of moisture over 30% starts germination.
http://en.wikipedia.org/wiki/Diastatic_powerhttp://en.wikipedia.org/wiki/Enzymehttp://en.wikipedia.org/wiki/Enzymehttp://en.wikipedia.org/wiki/Enzymehttp://en.wikipedia.org/wiki/Diastatic_power


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Wash the grain and remove germination inhibitors as well as all floating material.

The water quality must be at least as high as drinking water quality. The water uptake is

not evenly distributed over the whole kernel. The water uptake mainly depends on the

steep water temperature and the duration of the wet periods. Higher steeping water

temperatures and long wet periods increase the water level faster. Common steeping

temperatures are about 1218C. As the grain hydrates it swells to 1.4 times its original

volume. By blowing air into the base of the steeping vessel it is possible to prevent

packing and the barley is mixed. This also adds oxygen. The oxygen is needed by the

kernels for respiration. A lack of oxygen may provoke carbon dioxide accumulation.

Microbes may start growing. They compete with the grain for oxygen and reduce its

percentage.

Barley Germination

In the next step, the wet barley is germinated by maintaining it at a suitable temperature and

humidity level until adequate modification has been achieved. The germination process

creates a number of enzymes, notably alpha-amylase and beta-amylase, which will be used to

convert the starch in the grain into sugar.

The objectives of germination are:

Controlled breakdown of cell walls and matrixproteins.

Produce optimal level of hydrolytic enzymes. Hydrolyze certain barley reserves e.g. protein to

form free amino nitrogen (FAN).

Barley Germination


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Malt Kilning

If germination continued, a plant would grow, and all of the starches that the brewer hoped to

use would be used by the plant. So, the maltster gauges the germination carefully and stops

the process by drying where the malt is dried to remove enough moisture from each grain so

that further growth is halted.

The objectives of kilning are:

Terminate the modification process and the growth of the plant. Reduce moisture to levels suitable for grain storage. Conserve enzyme complexes developed during malting. Develop color and flavor (both taste and aroma) characteristics as required by the

brewer.

The process can be managed by the temperature

of fresh air and performance of the fan. The

heating has to be performed carefully at the

beginning. Common temperatures of the fresh

air for predrying of green malt start at around

65 C and end at around 80 C with full fan

power. The green malt bed can be divided inthree (upper, middle and lower) layers. The

incoming hot air is able to absorb moisture

from the green malt. At the beginning of the

drying process the exhaust air above the bed is

saturated and has a significantly lower

temperature.

A 1 to 2-foot thick drying zone develops near the floor and slowly

moves up through the bin. Grain below the zone comes toapproximate equilibrium with drying air and is usually dry

enough for safe storage. Grain at the top of the bin remains at its

initial moisture content until the drying zone moves completely

through the bin. You need to provide enough airflow (install a

large enough fan) so that the top grain dries before it spoils.


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The drying process starts at the lower layer and constantly develops through the bed. After 10

12 hrs, the temperature above the bed is rising and relative humidity of the exhaust air is

decreasing. Higher temperatures also increase the colour. Enzymes are partly inactivated.

Lower temperatures at higher moisture contents help to conserve enzymes.

In UBL, Ludhiana the grains initially contains 43% moisture and after drying it becomes 5%

approximately.

Moisture Determination

Heating the grain sample to drive off moisture and weighing before and after heating,

according to a standardized procedure, to find water loss is a direct method of moisture

determination.

Moisture Shrink

The removal of moisture from grain during drying causes a reduction in grain quantity

referred to as moisture shrink. The moisture shrink can be calculated using the following

equation.

Moisture Shrink (%) = Initial Moisture Content - Final Moisture Content

-------------------------------------------------------- x 100

100 - Final Moisture Content

Milling

Usually, malting is done at some other place, not in the industry. After malting, the barley

grains (now called malt) are sent to brew house for further processing. In United Breweries

Limited, Ludhiana the malt comes from Patiala. The first step of operation in the brew house

is the milling or grinding of the malt between rollers.

Foreign objects, such as stones or stray metal parts, can ruin a mill. Therefore they must be

removed from the malt before milling. In a dry mill, such objects can also generate sparks,

which pose an explosion danger. So before milling, we screen the grains two times through


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shaking or vibration screens, to remove dust particles, small stones, stray metal parts and

other rags. After screening, malt is sent to roller mill through bucket elevator.

The objectives of milling are to:

Split the husk longitudinally, exposing and separating the endosperm, without tearing thehulls

Crush the endosperm allowing complete wetting and therefore rapid extraction andenzymic digestion.

Minimize the quantity of fine flour produced.

There are different designs of malt mills, to meet the requirements. The husks have to be

removed but kept intact to serve later in the lautering process as a natural filter bed. If the

grist is too coarse, the yield of extract will be too low. If it is to fine the filter will be clogged

and the filtration process will become too slow. Here the right balance has to be found and

mostly a blend of different fractions is used. The milling step liberates the kernel from the

husk and breaks the kernel into smaller pieces, ultimately into flour. Milling of the malt is a

necessary step to make the starch contained in the kernel accessible in the next processing

step. On the one hand, grinding is of importance for extracting the inside of the malt or cereal

grain as much as possible out of the endosperm to facilitate the following extraction and

dilution steps.

The milling process should be accomplished by grinding the husk as little as possible because

the husk contains many undesirable components, such as resins that degrade beer quality. The

product of the milling operation is called grist.

Six-roller mills

Six-roller mills have three sets of rollers. The first roller crushes the whole kernel, and its

output is divided three ways: flour immediately is sent out the mill, grits without a husk

proceed to the last roller, and husk, possibly still containing parts of the seed, go to the

second set of rollers. From the second roller flour is directly output, as are husks and any

possible seed still in them, and the husk-free grits are channeled into the last roller.


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After milling, sieve analysis of grist

is done. For good lauter tun

performance Briggs et al suggest

that the grist should contain 15%

husks, 23% coarse grits, 30% fine

grits and 32% flour, while Kunze

suggests that the grist should consist

of 18% husk, 8% coarse grits, 56%

fine grits and 18% flour. In fact, the

optimum grist size distribution is

dependent on a brewerys specific

requirements for extract yield and

throughput, the modification of themalt and the loading on the lauter

tun. After milling, the grist is stored

in grist chamber.

The ideal grist for wort filtration in a lauter tun would contain:

No intact kernels The majority of husks split end to end with no endosperm attached The endosperm reduced to a uniform small particle size, called grits A minimum of fine flour.

Rice Cooker

There are several reasons to use non-malted crops in combination with barley malt. The

enzymatic power of barley malt is great enough to not only saccharify the starch contained in

barley, but also to saccharify the starch from non-malted cereals, but before these so-called

Roller Gap in mm

Mill settings top middle bottom

Coarse 13.0 10.5 11.0

Normal 10.0 8.0 6.0Fine 6.5 3.3 2.8


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adjuncts can be added to the mashing they have to be cooked in a separate vessel in order to

convert the mainly insoluble starch into a soluble gel.

Sometimes Rice Cooker works under slight pressure at approximately 104C. This requiresthat the adjunct cooker is equipped with a pressure control valve. An adjunct cooker is not

very different from a mash pan and has a steam heating coil and an agitator. The cooking

process bursts open the starch granules. Sometimes even a vacuum is applied to support the

bursting process. The enzymes can saccharify the starch only after the granules have been

burst open. Non-malted cereals can constitute from 10-40% of mash composition.

Rice Cooker is made of stainless steel. The agitator speed should be slow to deter the oxygen

uptake. In United Breweries Limited, Ludhiana two types of rice are used. They are:

1. Rice Flakes

2. Broken Rice

Rice flakes are directly put into mash tun while broken rice is first gelatinized in Rice Cooker

at 96. We give break at 85 so that enzyme can act on rice. In Rice Cooker,

broken rice is liquefied and converted into flakes as enzymes can act better on flakes during

mashing. The process of conversion of broken rice to flaked rice is called gelatinization.

Ingredients we put in rice cooker

Broken Rice 2450 kg alternate and cheap source of starch

Water 2000 litres to boil the broken rice

Gypsum 2 kg to control the pH

Termamyl 500 ml to avoid sticking of settling particles

H

Steam Consumption by Rice Cooker

The Rice Cooker is heated to the temperature of 96 with the help of steam. The steam is

present in the internal jackets at bottom and the side wall of the vessel. The steam is at


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temperature of 120 -130 .

Heat supplied by steam :

(Using steam tables and thermo-physical properties

table)

Q = m * *T

= (2450 + 2000) *4.91*(96 -45)

= 11,14,324.5 KJ

Amount of steam used = heat supplied / latent heat

= 11,14,324.5 / 2329

= 478.45 kg

The mass transfer pump is designed to transfer Rice Cooker mash to mash kettle for further

processing.

Mashing

Till the time the adjunct cereal is being cooked in Rice Cooker, we do pre - mashing in Mash

Kettle. During premashing, we add water and grist in Mash Kettle and mix them. Pre

mashing is done at 45. As the temperature reaches 45, we add adjunct cereal i.e. rice. If

we are using rice flakes, then they are directly put into Mash Kettle but if we are using

broken rice, then it is supplied from Rice Cooker through a pipeline. Now the actual processof mashing takes place.


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After the malt has been crushed in the milling process it is delivered to the mashing kettle and

pumped into large vessels known as mash tuns. These vessels are surrounded by steam

heating coils and are equipped with an internal agitator. Hot water is added to the ground

malt. Throughout the mashing process, water facilitates the extraction of the starch from the

grains and is the means of heat transfer driving the reactions.

Heat is applied to the mash tun and the mixture is slowly agitated to create a thick slurry

known as mash. The natural enzymes present in the barley begin to break down the starches

in the mash into simple sugars in a chemical process known as saccharification. Some

brewers will supplement the barley enzymes with additional proprietary enzymes to enhance

the saccharification process. These supplemental enzymes are added in a liquid form and are

usually very expensive. Temperature, holding times and pH are closely monitored during this

process to maximize the conversion of the starch into sugars.

Other ingredients we add in Mash Kettle are

Gypsum 5 kg a. To decrease pHb. To help in grushingc. Helps in yeast

settling

d. Give stability to -amylase

CaCl2 1 kg a. To control pH.b. For palletfullness

Lactic acid 2 litres To control pH

Promalt 900 gm

:


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Bio - chemical changes taking place during mashing:

Gelatinisation - starch granules swell with water and finally burst viscous/stickysolution which can be directly attacked by enzymes.

Liquefication - rapid reduction of viscosity by -amylase attacking gelatinised amylaseand amylopectin.

Saccharification - -amylase continues random attacks and -amylase attacks new non-reducing ends to form maltose.

In UBL, Ludhiana we do Infusion Mashing. In the infusion process, the entire batch ofmash is heated, with appropriate rests, to the final temperature. No part of the mash is

removed for separate boiling. In this system mash conversion (the malt starch is converted to

sugars) takes place in the same vessel as wort separation. As there are no heating stages it is

not necessary to have an agitation in the mash tun. The iso-thermal infusion mash is the

simplest way to make wort, however, since the technique lacks a protein rest, it is

recommended that you use mostly well modified malts. The infusion mash is also refered to

as the one-step mash, since the process requires only one step.

The temperature profile during mashing is different for both rice flakes and broken rice.

Rice flakes Broken rice

45 (rice +grist)

64 (35 min. rest)

71 (30 min. rest)

76

96 (rice) + 45 (grist)

64 (35 min. rest)

71 (30 min. rest)

76

During 35 minutes rest at 64 enzyme - amylase act while during second rest of 30

minutes at 71 , enzyme - amylase act. - amylase is also called liquefying enzyme as it

makes the grist in liquid form. At 76 these diastatic enzymes will get killed.


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Steam consumption during mashing

(Using steam table and thermo-physical properties table of water)

Total mass to be heated = 2440 kg ( rice)

+ 4135 kg (grist)

+ 11500 kg (water)

Temperature difference = 7645 = 31

Heat capacity of grist and rice = 2.3 KJ/Kg

Heat capacity of water = 4.2 KJ/Kg

Total heat supplied = * * +

* *

= 6575 *2.3*31 + 11500*4.2*31

=1966097.5 KJ

Steam consumed = heat supplied / latent heat

= 1966097.5 / 2354

= 835.215 kg

We do mashing for 70 minutes. After mashing is complete, we do iodine test to get

information about conversion of starch to sugar.

If we get

Yellowish brown colour means complete Saccharification


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Violetcolour means incomplete Saccharification

Input Output

Grains (rice + grist) Mash (18,075 kg)

6575 kg

Water Water

(0.05 * 6375=318.75) (318.75 + 11500 = 11818.75 kg)

Soluble Soluble

(0.75* 6375=4781.25 kg) (4781.25 kg)

Insolubles Insolubles

(0.20 * 6375 = 1275 kg) (1275 kg)

Therefore Water added (11500 kg)

Lautering

When the mashing process is finished, the insoluble husks, grist, proteins, cellulose and still

not converted starch have to be removed from the wort

before further processing, to obtain a clear liquid.

Lautering is the separation of the extracts won during

mashing from the spent grain. The filtration can be

carried out with lauter tun .

Design of lauter tun

A lauter tun is a cylindrical vessel with a perforated false

bottom. The false bottom can be opened and closed to

flow. The false bottom in a lauter tun has thin slits to hold

back the solids and allow liquids to pass through. The

Mass

balance

during

Mashing


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solids, not the false bottom, form a filtration medium and hold back small solids, allowing the

otherwise cloudy mash to run out of the lauter tun as a clear liquid. To prevent the filter from

clogging, the Lauter Tun is equipped with a very complex raking machine (agitator). The

raking machine has vertical, rotating blades, knifes and beams for different purposes, as to

prevent the filter bed from becoming too dense, assisting in washing the filter bed with water

and finally to push the solids out of the lauter tun. Cutting blades hang from these arms. The

blade is usually wavy and has a plough-like foot. Each blade has its own path around the tun

and often the whole rake assembly can be raised and lowered. Attached to each of these arms

is a flap which can be raised and lowered for pushing the spend grains out of the tun. The

brewer, or better yet an automated system, can raise and lower the rake arms depending on

the turbidity (cloudiness) of the run-off, and the tightness of the grain bed, as measured by the

pressure difference between the top and bottom of the grain bed.

Lautering has two stages

First wort run-off: During which the extract is separated in an undiluted state from thespent grains

Sparging: In which extract which remains with the grains is rinsed off with hot water.

This separation is actually two different problems.

The liquor needs to be filtered from the particles Much of the sugar is still contained within the spent barley grains.

To solve both of these problems at once, the grains are used to form the structure of a deep

bed filter. Before pumping into the lauter tun, the mash is vigorously stirred to distribute the

solids homogeneously in the fluid. When the mash is pumped now into the lauter tun, the

false bottom remains closed for about 30 minutes to allow the husks to form a filter bed.When the bottom is finally opened to flow, the agitator starts spinning slowly around, blades

rotating.

The liquid is slowly drawn through a perforated bottom in the vessel containing the mash

and introduced back the top of the vessel. In this way, the small suspended particles in the

liquor become trapped in the bed of grains. When the recycled liquor becomes clear, it is

tapped from the bottom of the vessel and hot water is introduced slowly to the top. The fluid

part of the mash passes slowly through the filter bed made of the husks and grist. The first

filtrate is still too cloudy and has to be recycled through the lauter tun, but as soon as the

liquid is clear enough, it is pumped into the wort kettle.


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Still there is some sugar content present in spent grains, we can extract that sugar content

through Sparging. We are transferring sugar from spent grains to clean hot water. The mass

transfer works because the sugar concentration in the grains is higher than that in the hot

water, so the sugar is extracted out of the grains.

When all the liquid mash is pumped into the wort kettle the filter bed is washed with hot

water to increase the yield (Sparging). The hot water is sprayed from nozzles, which are built

into the raking machine. A system will introducing sparge water into the lauter tun. Most

systems have a ring of spray heads that insure an even and gentle introduction of the sparge

water. The watering system should not beat down on the grain bed and form a channel.

Sparging water conditions:

Its pH should be between 6.46.7. Its temperature should be between 76 - 78.

a. If temperature is less than 76 , no proper extraction of sugar takes place.

b. If temperature is more than 78 or 80, leaching of polyphenols take place. It gives

harshy flavour to wort.

Sparging is done three times

Sparging number Amount of hot water

used

Time for which it is

done

Extract called

Before sparging No water used 50-55 mins Sweet wort

1st sparging 6000 lts 20-25 mins 2n extract

2n sparging 6100 lts 20-25 mins 3r extract

3r sparging 1000 lts 4-5 mins Last run

Eventually the separation is completed, resulting in a dilute solution of malt sugars (this is the

same stuff as is concentrated and sold as malt extract in the supermarket) and the spent

grains. Since the spent grains still contain a lot of carbohydrate and fibre, they have quite ahigh nutritional value and are sold as animal feed. Part of the task of the chemical engineer in


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all the process industries is to operate the process in such a way as to minimise the generation

of waste, both to help the environment and to improve the profitability of the operation.

The filtrated fluid obtained from the mashing and lautering process is called wort. It is an

aqueous liquid that contains mainly fermentable sugars. The malt enzymes are still in an

active state and there are proteins and other by-products. The next step of operation in the

brew house is wort boiling.

Input Output

Mash (18075 kg) Wort (26,668.75 kg)

Soluble (4750 kg)

Water (11,818.75 kg) Water (21,918.75 kg)

Soluble (4781.25 kg)

Insoluble (1275 kg) Spent Grain (3785 kg)

Water (2500 kg)

Sparging (13,100 kg) Insoluble (1260 kg)

Water Soluble (25 kg)

Drain Water (1521.25 kg)

Water (1500 kg)

Soluble (6.25kg)

Insoluble (15 kg)

MassBalance In

Lauter Tun


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Wort Boiling

Wort boiling is a complex process during which a wide range of chemical, physico-chemical,

physical and biochemical reactions take place. It is the most energy intensive stage in the

brewing process. From the lauter tun the filtrated wort is pumped into the wort kettle, made

of stainless steel. Wort kettles are similar to mash pans but mostly without an agitator and a

different heating system.

There are several reasons why a good wort boil is important

1. Wort sterilization

Boiling your wort provides enough heat to render the wort free from bacterial contamination.The wort bacteria are easily killed by heat. The low pH and the antibacterial action of certain

hop constituents will ensure that the pathogenic and spore forming organisms that would

otherwise.

2. Enzyme inactivation

Most of the enzyme action ceases early during wort collection, either due to raising the mash

temperature for mash-off or by sparging at a higher temperature in an infusion mash. Boiling

ceases the remaining enzyme activity and fixes the carbohydrate composition of the wort, andhence the dextrin content of the final beer. Dextrins are complex carbohydrates. In the

absence of enzyme activity to break them down into simpler sugars, brewers yeast cannot

ferment.

3. Boilings effect on proteins and hot break

Under the favorable conditions of wort boiling, proteins and other polypeptides present in the

wort will combine with polyphenols or tannins. Protein-tannin complexes collide with other

protein-tannin complexes and stick together until they achieve a certain mass and precipitateout of solution. Boiling also can destroy a proteins three-dimensional structure. Protein and

tannins are the primary constituents of the hot break in the kettle. The hot break is the brown

scum that forms on top of the wort, formed due to coagulation of proteins, formation of

protein-polyphenol complexes, and reaction with hop compounds to create larger particles

that will sediment out in the whirlpool at the end of the boil. These reactions occur at higher

rates at higher temperatures and more agitation.


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4. Solubilize and isomerize hops

Although there are a great many reactions occurring during the kettle boil, the principle one

of interest is the isomerizationand subsequent solubilizationof alpha acids. Isomerizedalpha acids are the molecules responsible for the bitter flavor in beer. The chief component of

alpha acids is the compound humulone. The isomerization of humulone to isohumulone is

facilitated by the presence of magnesium ions. The extraction and isomerization are very

inefficient, however, and as many as 70% of the alpha acids remain unconverted, and hence

insoluble.

5. Volatalize aromas

Dimethyl sulphide (DMS), an off flavour component that forms during the boil from S-

methylmethionine (SMM), is quite volatile at wort boiling temperatures. Given enough time,

say 60 minutes of boiling, DMS should be formed and driven off enough to bring it below the

detectable flavour threshold. During boiling we're basically distilling the DMS out, as it is

more volatile than water. However, you must evaporate some water in order to do this. The

amount of water needed to evaporate is dependent on the concentration of DMS that you

need to get rid of. The more DMS in the wort, the more water you need to evaporate. There is

a minimum amount of water that you need to get rid of certain concentration of DMS,

regardless of what type of wort boiling system you are using.

6. Hop aroma

Hops also contain an essential oil component, which is responsible for the characteristic hop

aromas. Each oil imparts its own smell, and hop aroma is made up from the combinations of

many smells. The oils are soluble in hot wort and are very volatile. So, they are soon boiled

away in the steam from the kettle. This is why many brewers add a charge of hops as late inthe boil as possible to try to trap the aroma before it is evaporated away. Dry hopping is

another technique designed to avoid losing volatile hop compounds.

7. Colour development

Colour pick-up in the kettle is a combination of several factors. The caramelization of wort

sugars darkens the wort as it boils. Loss of an H2O molecule from the complex sugar

molecule forms a double bond inside the sugar molecule, which changes the way the sugar

molecule absorbs light, thereby affecting the color.


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8. Concentration of the wort

In a large brewery, up to 10% of the kettle contents can be lost due to evaporation during a

boil of normal duration. This increases the original gravity of the wort accordingly.

9. Good place for the addition of sugar

Extra sugar is added here to increase the gravity of wort. In UBL, Ludhiana we add 700 kg of

sugar.

10. pH

Wort pH will fall from 5.65.8 at the start of boiling to around 5.25.4 at the end. This is

primarily due to the precipitation of calcium phosphate. Calcium ions in brewing water reacts

with phosphates from the malt to form calcium phospate and hydrogen ions, which lower

wort pH. This demonstrates the importance of excess calcium ions in the wort after mashing.

For this reason, it is sometimes a good idea to add gypsum to the kettle.

Wort boiling system (External Vertical Calandria)

Wort kettles come in different shapes and with various heating systems. The aim is to gain

ideal heat distribution and heat transfer with the different sizes of kettles and saving as much

energy as possible. The kind of wort boiling has also an influence on the quality of the wort.

In UBL, Ludhiana we use external heating system (vertical calandria) for wort boiling.

Process Operation and Control

During filling of the kettle, wort is received at 70-75C and must be heated to boiling point.

Wort is circulated through an external vertical calandria by pumping during the filling

process such that the contents of the kettle are at boiling point at the end of fill and this can

save overall batch time in the brewhouse. The temperature difference between the wort and

the steam used for heating is controlled during the heat up phase and once at boiling point,

pumping is discontinued and the thermosyphon drives itself. No pumping is required once the

kettle is boiling, and the contents can be circulated at

up to 10 times per hour, driven by the large difference in density between the liquid-vapourmix in the heater and the liquid in the kettle. During the boil, clean steam condenses on the


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heating surface transferring its latent heat to the wort. This latent heat is required to evaporate

the water and volatiles from the wort, and the amount of heat input required only needs to

correspond with the latent heat of evaporation at the pressure of the wort, plus an allowance

for heat loss from the kettle. The water vapour from the wort is at a lower pressure than the

original steam, but it holds all the heat in the original steam less the sensible heat left behind

in the condensate. With each successive brew the surfaces get fouled, resulting in a lower

heat transfer coefficient and the mass flow of steam at constant pressure falls as the rate of

condensation is reduced. To achieve the required evaporation rate, the temperature (and

consequently pressure) of the steam must be raised, which is best achieved by installing a

steam mass flow meter, the signal from which modulates a flow control valve.

NOTE: In case of external heating system no natural hops should be used but hop pellets or

hop extracts because the hops leaves and solids can block the passage through the heat

exchanger.

Heat Transfer and Temperature

Heat transfer is governed by Fourier's Law which is stated as

Q = UA ()

where Q is the rate of heat transfer, U is the overall heat transfer coefficient, A is the heating

surface area is the steam temperature, and is the wort temperature. It follows that an

increase in heating surface area requires a decrease in steam temperature to maintain the same

heat input and achieve the same evaporation. With the very large surface area of a modern

external wort heater the steam temperature can be reduced to 110C - 115C compared to

135C to 140C for an internal heater. This correlates with less heat damage to the wort.

Evaporation Percent

Evaporation is usually expressed as percentage of total volume of wort at the start of boil. It

is difficult of measure accurately the volume of boiled wort due to its turbulence.

Evaporation percent =

100 - (post-boil volume x 100 pre- boil volume)


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For example:

Say you collect 267 hectolitres of wort and boil it down to 240 hectolitres.

Evaporation percent = 100 - (24000 267),

= 10090

= 10%

Most brewers target the evaporation percent between 8% - 10%.

Steam Consumption during wort boiling

(Using steam table and thermo-physical properties table of water)

Enthalpy balance with negligible heat of dilution

Total heat required for wort boiling = +

= heat required to raise temperature from 78 to 100

= * *

= specific heat of wort = 4.19 ( almost same as water)

= mass of wort = 26700 kg

= temperature difference = 22

= 26700 * 4.19 * 22

= 2461206 KJ

= heat required for evaporation of 10% of wort

= m *

m = mass of wort evaporated


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latent heat of vapourization

= 2670 * 2257

= 6026190 KJ

Total heat supplied by steam = 2461206 + 6026190

= 8487396 KJ

Steam consumed = 8487396 / 2257

= 3760.476 kg

Steam economy = No. of kg vapourized / kg of steam fed

= 2670 / 3760.476

= 0.71

Types of boiling that occur in calandria

Three forms of heat transfer can take place inside the heating tubes:

1. Film Boiling2. Forced Convection Boiling3. Nucleate Boiling

Film boiling is not desirable, as a vapour film forms on the heating surface and prevents the

heat transfer to the wort, causing rapid fouling. It can occur at fairly low temperature

difference.

Forced convection will take place when there is low temperature difference between wort and

heater or when bubble formation is suppressed by application of backpressure. To achievehigh rate of heat exchange, flow in tubes must be turbulent.


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Nucleate boilingmakes use of bubble formation to cause rapid turbulence. The presence of

bubbles also helps in the removal of volatiles. Nucleate boiling (phase change) can be

encouraged or suppressed by the pressure maintained.

Whirlpool

The whirlpool kettle is used to separate undesirable substances from the hot wort. The

particle size of these substances is only 30-80 m. These substances are collectively calledhot trub and are present at a concentration of 40-80 grams per hectolitre of wort. A whirlpool

is a hydrodynamic trub separator using centrifugal forces to sediment insoluble substances

from the wort after boiling. Trub has a negative influence on fermentation and the taste of

beer.

Flow and forces in a whirlpool

The tangential injection causes the liquid to spin with about 10 rpm and form a vortex. As acombined result of centrifugal forces and friction on the wall, the trub accumulates in the

bottom of the whirlpool in the shape of an inverted cone. After about 30 minutes the wort is

pumped from the outlet to the wort cooler.


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Settlement of Solids ( Stokes law)

Particles settle naturally under the influence of gravity, as described by Stokes Law. Stokes

Law states that the rate of sedimentation of an idealised spherical particle is directly

proportional to the difference in the density of the particle and the liquid medium, the

acceleration due to gravity, and the square of the radius of the particle, and inversely

proportional to the viscosity of the liquid. Thus if wort or beer is left for a sufficiently long

time, it will clarify itself; this is the basis of the laggering process.

Where,

= rate of sedimentation of a spherical particle

= density of the particle

= density of the medium (wort or beer)

= diameter of the sphere

g = acceleration due to gravity

= viscosity of the medium.

Stokes Law suggests two possible strategies for increasing the rate of clarification. The g

term may effectively be increased by means of a centrifuge or the radius of the particle may

be increased by the use of finings. Centrifuges are particularly effective at removing yeast,

but generally less effective on the very small particles that finings (whirlfloc) are particularly

good at removing. Since the speed of settlement is proportional to the square of the radius a
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modest increase in particle size can yield a profound decrease in settlement time. This

therefore, makes increasing particle size by flocculation, a very attractive method of

decreasing settlement times. Coagulation is not a simple process and depends upon the nature

of the particulates and the liquid.

Wort Cooling

The hot wort must be cooled because temperatures above 40 C kill the yeast during

fermentation. The cooling process is carried out in closed systems, mainly plate heat

exchangers.

Design of Plate Heat Exchanger

The plate heat exchanger (PHE) is a specialized design well suited to transferring heat

between medium- and low-pressure liquids. Two plates form a cell with a flow of the cooling

medium followed by two plates forming a cell with a flow of the hot medium. The plates

have a profile guiding the flow from the inlet at one side on the top to the outlet at the other

side at the lower end in a cell. Both media flow exactly in counter flow pattern. The hot

medium becomes gradually cooler as the cold medium becomes gradually warmer. Stainless

steel is a commonly used metal for the plates because of its ability to withstand high

temperatures, its strength, and its corrosion resistance. The plates are often spaced by rubber

sealing gaskets which are cemented into a section around the edge of the plates. The plates

are pressed to form troughs at right angles to the direction of flow of the liquid which runs

through the channels in the heat exchanger. These troughs are arranged so that they interlink

with the other plates which forms the channel with gaps of 1.31.5 mm between the plates.


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Heat transfer

The plates produce an extremely large surface area, which allows for the fastest possible

transfer. Making each chamber thin ensures that the majority of the volume of the liquid

contacts the plate. The troughs also create and maintain a turbulent flow in the liquid to

maximize heat transfer in the exchanger. A high degree of turbulence can be obtained at low

flow rates and high heat transfer coefficient can then be achieved. The heat exchanger plates

are thin (0.5mm) to allow optimal heat exchange. The surfaces of plates are embossed to

cause turbulent flow and speed up heat transfer.

The efficiency of plate heat exchanger is affected by fouling. If fouling increases, the heat

transfer coefficient reduces, and higher flow of chilled water will be required to achieve

the wort outlet temperature.

In UBL, Ludhiana we use single stage cooling process, in which hot wort at 100 is to be

cooled to temperature of 15 by bringing it in contact with chilled water at 4. The

temperature of outlet hot water reaches about 80. The wort temperature at the cooler end is

measured by the resistance bulb thermometer and adjustments are sent to chill water throttle

valve to achieve the required wort temperature.

Advantages of plate heat exchanger

Compactness- The units in a plate heat exchanger occupy less floor space and floor loadingby having a large surface area that is formed from a small volume. This in turn produces a

high overall heat transfer coefficient due to the heat transfer associated with the narrow

passages and corrugated surfaces.

Flexibility- Changes can be made to heat exchanger performance by utilizing a wide range offluids and conditions that can be modified to adapt to the various design specifications. These

specifications can be matched with different plate corrugations Low Fabrication Costs- Welded plates are relatively more expensive than pressed plates.

Plate heat exchangers are made from pressed plates, which allow greater resistance to

corrosion and chemical reactions.

Ease of Cleaning- The heat exchanger can be easily dismantled for inspection and cleaningand the plates are also easily replaceable as they can be removed and replaced individually.

Temperature Control- The plate heat exchanger can operate with relatively smalltemperature differences. This is an advantage when high temperatures must be avoided. Local

overheating and possibility of stagnant zones can also be reduced by the form of the flow

passage.


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Calculations related to plate heat exchanger

A plate heat exchanger is used to cool wort from 100C to 15C. The wort passes through it

at a flow rate of 360 hl/hr. Cooling water at 8C flows counter-current into the plate heatexchanger at a flow rate of 405 hl/hr and its outlet temperature is 80C.If each plate has an

area of 0.6 .

Density of wort = 1080 kg/

Density of water = 1000 kg

Specific heat of wort = 4.0 kJ/(kg K)

Specific heat of water = 4.2 kJ/(kg K)

Heat transfer coefficient = 3000 W/.

Using heat balance

Heat lost by wort = heat gained by water

** = * *

Heat lost by wort = 360 kg/hr * 4 KJ/(kg K) * 85C

= 122400 KJ/hr

= 34 KW

Heat gained by water = 405 kg/hr * 4.2KJ/(kg K) * 75C

= 122472 KJ/hr

= 34 KW

Calculating LMTD


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= (207) / (ln 2.86)

= 12.37

Using Design Equation of plate heat exchanger

Q = U * A *

Total area of plates, A = 34000 / (3000 * 12.37)

= 91.62

Total number of plates used = Total area of plates

-------------------------

Area of one plate

= 91.62 / 0.6

= 153 plates

So for the above cooling operation we need 153 plates.

Aeration

Aeration is the process by which air is circulated through, mixed with or dissolved in the

wort. In its broadest sense, aeration is the process by which the area of contact between wort

and air is increased by mechanical devices. In venturi pipes there is a substantial increase inflow velocity where the pipe is narrowed. The wort, which runs through the aeration nozzle,

creates a slight vacuum which draws air into the unit.

Air is introduce through a jet nozzle & is through mixed by eddy current in the wort in the

turbulent flow. The lower the temperature, the greater is the solubility. The air is directly

injected into the wort that turbulently flows through a pipe.

The basic purpose of aeration is the improvement of the physical and chemical characteristics

of wort. Primarily, this improvement involves the reduction of objectionable tastes and

odours, but some additional benefits of aeration, as a preliminary step to other purificationprocesses have also been noted.


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Fermentation

The term fermentation refers in general to those processes that are caused by microorganismsthat degrade nitrogen free substances. These processes occur slowly and are characterised by

the formation of gases and the liberation of heat. The names of the different fermentations are

derived from either the final product or the microorganism that caused the fermentation. In a

brewery, only alcoholic fermentations are of interest. Here, a variety of fermentable sugars are

degraded by yeast into ethyl alcohol (ethanol) and carbon dioxide according to the following

formula:

C6H12O6 2 C2H5OH + 2 CO2 + 230 kJ

Glucose Ethanol Carbon dioxide


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Yeast pitching

Strain Used- Saccharomyces uvarum, Saccharomyces cerevesiae

Yeasts are single celled organisms (fungi). Yeasts are mono-cellular microorganisms that are

common and widespread in nature, which reproduce by budding or fission. The viscous yeast

suspension is added directly into the aerated wort. The yeast can be dosed with suitable

pumps into the wort supply line of the fermenter, or blended with the wort in so-called

pitching vessels. The addition of yeast is called "pitching" in the brewer's language. It is very

important to intensively aerate the yeast before dosing. If this is not done, a delay in

fermentation is inevitable. The fermentation process is initiated by the addition of 0.5 0.7 l

of a heavy yeast slurry per hectoliter of wort, corresponding to 1520 million yeast cells per

millilitreof cold and aerated wort. After the addition of yeast, the wort is called youngbeer

or simply beer.The single yeast cells must quickly come in contact with the nutrients of the

wort. Consequently, the yeast is injected continuously into the flow of the coldwort.

Fermentation process

+ 6> 6O+ 6

>OH + 2

Fermentation process is divided into 3 phases

Lag phase Log phase Stationary phase

Lag phase

The lag phase is the time during which the yeast become acclimatized to the wort and prepare

to reproduce and consume massive amounts of sugar. In this phase, oxygen is extremely

important. Oxygen is used by yeast for synthesis of sterols and unsaturated fatty acids that are

necessary growth factors. Without oxygen, these lipids cant be bio synthesized and growth

will be very limited.


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Log phase

The log phase is a time of exponential growth of the yeast culture. The preparation of the yeast

made during the lag phase allows rapid multiplication of cells and consumption of sugar. Yeast

reproduce asexually by budding; the adult cell forms a daughter cell that is an exact genetic

copy itself. The yeast turns one molecule of glucose into two molecules each of ethyl alcohol

and carbon dioxide.

Stationary phase

The stationary phase is the last stage where the yeast population reaches maximum density and

the remaining sugars are consumed. As the available sugar decreases, the yeast begin to

prepare for a period where there is a lack of food. It is here where fermentation comes to a halt

and yeast begins to dormant. When the yeast have consumed all of the sugar, flocculation

begins. The rest allows time for the yeast to convert or reduce some less desirable compounds,

especially diacetyl, to more acceptable or desirable compounds.

Changes during Fermentation

Changes in the Composition of Nitrogen CompoundsYeast converts nitrogen compounds from wort to synthesize its own cellular substances. The

free amino nitrogen (FAN) content is reduced from 200250 to 100120 mg/l.

pH DropThe pH decreases from 5.4 5.6 in wort to a value of 4.3 4.6 and then remains constant.

Lower pH values, for instance below 4.2, must be avoided because they impair an acidic beer

taste.

Precipitation of Bitter Substances and PolyphenolsThe non - isomerized - acids are captured from ascending bubbles and carried ahead to

the foam. The loss of bitter substances ranges from 25 to 40% during fermentation.


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Content

is enriched in fermenting beer. The solubility ofin beer dependson temperature andpressure. Most of the produced during fermentation is, however, recovered.

Undesired side reaction

Diacetyl which can give a butterscotch flavour but needs to be managed closely to avoid a

rancid flavour.

Degree of fermentation

The degree of fermentation of wort is determined by :

% Fermentation =

(% initial extract - % final extract) x 100

----------------------------------------------------

% initial extract

The dominant practice is to ferment all fermentable extract. One should note that not all extract

formed during the mashing step in the brewing process consists of fermentable sugars, also a

certain amount of non-fermentable sugars are formed.

The following example illustrates this point:

Initialextract:2.2%

Final extract: 2.0%

% Fermentation =

(12.2 - 2.0) x 100

= 83.6112.2

The degree of fermentation relates to the taste of a beer.


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Dissipation of heat and heat transfer

The dissipation of the heat from the fermenter follows the principle of heat transfer. Most of the

heat transfers occur through conduction and will follow the direction of the heat gradient. The

heat transfer depends on the size of the fermenter. Small fermenters have smaller volume and

therefore a high surface area to volume ratio. This makes heat the fermenter very fast and

efficient. Under this situation the fermenter will

Cooling jackets is good heat exchanger. As the fermentation reaction is exothermic reaction, a

lot of heat is produced. We must cool the fermentation vessel by means of cooling jackets. This

type of cooling jackets is commonly used in the case of indirect evaporation. The cooling is

done by glycol. The glycol is fed in from below and passes out at the top.

Mass Transfer in Fermentation

Film theory

The two film theory is a useful model for mass transfer between phase. Mass transfer of solute

from one phase to another involves transport from bulk of one phase to the interface, and thenfrom the interface to the bulk of the second phase. This theory is based on idea that a mass

transfer boundary layer forms whenever there is contact between two phases. Mass transfer

through the film is by molecular diffusion and is the major resistance.

Oxygen transfer from gas bubble to cell

Eight steps involved

Transfer from the interior of the bubble to the gas-liquid interface Movement across the gas-liquid interface Diffusion through the relatively stagnant liquid film surrounding Transport through the bulk liquid Diffusion through the relatively stagnant liquid film surrounding Movement across the liquid-cell interface If the cells are in floc, clump or solid particle, diffusion through the solid of individual

cell.

Transport through the cytoplasm to the site of reaction.


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Maturation

After the hard work of primary fermentation, beer needs to rest. At this stage the brewer is

looking to mature the beers flavour, reduce the rougher alcohols, stabilise it and minimise any

dissolved oxygen. It may also be clarified. During maturation, the temperature of the green beer

is lowered to force the precipitation of the yeast. To separate yeast from green beer by this

cooling and decanting process takes about 12 to 15 hours. The green beer is transferred to

maturation tanks where it is tored at a temperature of -1. The yeast is pumped to storage

tanks for use in the next batch. Generally, yeast is used about five times. If the yeast is infected,

it is washed with acid before it is used in the next batch.Yeast that is no longer suitable for

fermentation is sold to other industries such as the pharmaceutical or animal feed

industries.After this primary fermentation, the wort is called "green beer". Green beer has arough flavour and before it is ready for consumption it has to undergo maturation or ripening

process that is known as "lagering".

We add three chemicals after fermentation for protein settlement. They are

Biofien Profex KMS

This process will improve the quality of the beer and eliminate undesired fermentation by-products as diacetyl, aldehydes and sulphur containing substances by biochemical processes.

In UBL, Ludhiana both fermentation and maturation takes place in one tank in off season. This

tank is called CCFV i.e. cylindro-conical fermentation vessel. During season time, maturation

takes place in another vessel.

Cleaning in Place

C.I.P means cleaning in place. This technique is used to clean fermentation vessels. Its

procedure is:

Rinsing with hot water for 10 minutes Hot caustic circulation for 30 minutes Cold water circulation for 10 minutes Superoxide circulation for 30 minutes


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When caustic is used for cleaning, it is necessary to ensure that the C has been removed

from the tank because otherwise as a result of reaction

2NaOH + C>

C

+

or

NaOH + C> NaHC (insoluble sodium hydrogen carbonate)

Filtration

Upon completion of the maturation process, the beer is filtered. The purpose of the filtrationis to improve the stability of the beer and to give it brightness and clarity. Filtration does not

only improve the appearance of the beer.

Several different substances must be removed from the beer including yeast, precipitated

proteins, hop resins and sometimes beer spoiling microorganisms. All these substances can

cause turbidity and a ropy effect like a veil. The turbidity forming substances have distinctly

different particle sizes and have different filtering characteristics.

One should differentiate between gross dispersions and colloids. Gross dispersions have a

particle size > 0.1 m and can be seen with the naked eye. Examples are yeast and coagulated

proteins. The particle size of colloids is between 0.001 and 0.1 m. Colloids are best

observed with refracted light by sending a beam of light through the fluid.

The filtration steps fulfil two roles

To remove suspended materials from the green beer (the real filtration)

To unhinge potential turbidity formers (stabilization).

Metal Candle Filter

Metal candle filters have stainless steel housings. Their shape is cylindrical and they are

mounted in a vertical position. Filter candles have a diameter of 2035 mm and are of

various lengths up to a maximum of 2.5 m. A filter surface area of up to 180

can beachieved in the pressure vessel by a parallel arrangement of candles. Internally, they contain


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many filter elements that are made from a fine wire mesh. The pore size of the mesh is 70

m. The purpose of this pore size is to retain the filter aid, the diatomaceous earth. The

suspension is made by mixing beer with Kieselguhr.

The candles have permeable materials on their surface and are

traversed through from outside to inside. The filtrate is drained off through the inside of the

candle. The fluid passes through a very porous filter material. Particles that are to big are

retained in the filter media. In this process, also adsorption plays an important role. The

problem here is that as the particle retention increases, the volume flow of clean beerdecreases. Particles are retained in these channels by adsorption.

Kieselguhr suspension is pumped directly into the beer line. As the Kieselguhr suspension

enters the filter, it forms a filter bed on the stainless steel mesh. Closed loop circulation is

established until the filtrate runs clear. The turbidity causing substances are retained on the

Kieselguhr filter bed.
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Beer Stabilization

The removal of turbidity - forming materials from beer is carried out by adsorptive during

kieselguhr filtration.

Two major groups of substances count as turbidity formers:

1. Proteins

2. Tannins

Proteins are removed by adsorption using colloidal silica. This is done by adding silica to the

kieselguhr dosage. Tannins are nearly exclusively removed by adsorption using

polyvinlylpyrrolidon (PVPP). PVPP is added to the kieselguhr.

Carbonation

Carbonation refers to the dissolving ofcarbon dioxide in an aqueous solution. Carbon dioxide

used here comes from brewery itself. The carbon dioxide released during fermentation is used

here, after purification.

Principle of Carbonation

Carbonation is based on the principle of Henrys Law. Henrys Law has two parts. Part one

states that as pressure increases, solubility of gases in liquids increases. Part two states that as

temperature increases, solubility of gasses in liquids decreases. More pressure means more

gas can be dissolved in a liquid. Decreasing pressure causes that gas to come out of the

liquid. Colder liquids hold more gas than warmer liquids. As a liquid warms up, the gas starts

to come out of solution.

The classic example of Henrys Law is the bottle of your carbonated beer. Before the bottle is

opened, the contents of the bottle are under pressure. Because of this pressure, the carbon

dioxide is soluble in the liquid portion of the beverage. When you open the cap, you release

the pressure and the carbon dioxide becomes less soluble. Because the carbon dioxide is less

soluble, it cant remain dissolved and comes out of solution in the form of bubbles.

The amount of carbon dioxide that dissolves is a function of time, with the rate decreasing

exponentially as equilibrium is approached. Carbon dioxide levels are stated as volumes of

gas at standard temperature and pressure per volume of beer. Fixing the temperature and

pressure at appropriate settings will bring about the desired carbon dioxide concentration.
http://en.wikipedia.org/wiki/Solvationhttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Aqueous_solutionhttp://en.wikipedia.org/wiki/Aqueous_solutionhttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Solvation


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Bright Beer Tank

The filtered beer, after carbonation is stored in the so-called bright beer tanks. These tanks

are also referred to as pressure tanks. Bright beer tanks are normally vertically installed

cylindrical tanks or cylindrical, conical tanks. These tanks are usually constructed from

stainless steel. Inorganic soil accumulates in the form of predominantly mineral beer stone.

Sometimes it can be observed after three filling and emptying cycles. Filtered beer should not

be stored for extended periods in these tanks to avoid a variety of problems that could have a

negative influence on the quality of the beer.

Bottling

Bottle washing

Bottle washing is an integral part of a beverage manufacturing process. Bottle washing seems

to be a simple and easy task to accomplish; however, in actual practice it is not. Bottle

washing has evolved into a highly automated process that requires a thorough understanding

of many technical considerations. The purpose of bottle washing is to remove all soils from

the inside and outside surfaces of the bottles.

More specifically, this includes removing

product residues and adhesive, dust, dirt, rustrings (from metal caps), moulds, insect eggs

and larvae, and other soils that may be present.

A major function of the bottle washing

operation is to remove all labels and exterior

soils to prepare the bottle for re-labelling. The

bottles must exit the bottle washer in a clean, preferably sparkling, and sanitary condition.

They must be free of all pathogenic and spoilage organisms.


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Bottle Inspection

After leaving the bottle washer the bottles have to be checked whether they are in a proper

state to be filled and distributed to the consumer. Checking has not only to verify the hygienicstate of the bottle (no residues) but also the physical state. Certain damages may leave the

bottle unfit for filling or may represent a risk to filling equipment. Even when a bottle can be

properly filled, it has to be verified that the bottle cannot be a source of harm to a consumer.

Bottle Filling

Bottle filling machines are always built as revolving machines with upto 200 filling valves.

The bottles are transported to the filler on a conveyor belt, than separated to a predeterminedspacing by a separating device, and positioned on a lifting platform under the filling elements

by using a star-wheel-loading-device.

During rotation of the filler the bottles pass through several stages

Pressing against the filling elements

Evacuation and counter-pressurization filling

Filling level adjustment

Pressure release

Lowering from the filling elements

Crowning

After filling, the bottles have to be closed as soon as possible. Therefore, the closing machine

is built into the same unit as the filler and they are equipped with a common drive to ensure

synchronous operation. The indented part of the crown cork is pushed over and bent inwards

over the lip at the bottle mouth, thus sealing the bottle. A crown cork, as delivered by its

manufacturer, has an outer diameter (d2) of 32.1 mm (including the 21 claws) and a height

(h) of 6.0 mm. The internal diameter (d 1) is with 26.75 mm as wide as the outer diameter of

the bottle mouth. Closing elements move also up and down to be fitted onto the bottles.


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Labelling

During the first rotation, the rotating gluing or label

intake elements (2) are coated with adhesive supplied

by an adhesive applicator (3). Then they pass the label

magazine (1). Due to the tack provided by the glue-

covered surface of the intake device, a label is picked

up. In this process step, it is essential that the labels

easily separate from the stack in the magazine to avoid

that two or more labels are taken at the same time. In

the second rotation, the labels covered with glue on

the reverse side are taken by gripper (4) and pressedwith the printed side pointing inwards against a

sponge. In a third rotation, the labels are rolled with their adhesive-coated side against the

bottle and the gripper releases the label. The labelled bottles are then moved passing brushes

and rubber rollers to attach the labels firmly to the bottle.

Bottle pasteurization

To guarantee a long shelf life the beer, it

has to contain as little beer spoiling

microorganisms as possible. The most

reliable method for achieving this objective

is the pasteurisation of the filled bottle in atunnel pasteuriser, because this process

covers also the high risk of contamination

in the filling process. In a tunnel

pasteuriser, the bottles pass on special

conveyor chains with a grid structure to

permit a high water passage through a long

tunnel The tunnel is divided in a number of

zones with a vigorous water spray of gradually increasing temperature. On passing through

the tunnel the temperature of the bottles and their content is gradually increased by the water


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sprays, until the desired pasteurisation temperature is reached and maintained for a while. On

their further way towards the end of the tunnel the bottles pass then through zones with

gradually decreasing spray temperatures, thus cooling the bottles down until they havereached ambient temperature upon leaving the spray-tunnel.

Efficient heat exchange depends on a vigorous water circulation over the bottles. Therefore,

the water is pumped through large pipes. Instead of spraying jets, there are large rectangular

openings on the underside of the pipes. Close to the openings, special deflectors produce

highly turbulent currents to produce a large contact area between the passing bottles and the

pasteuriser water. The water is collected in large vessels under the spraying sections and,

after filtration through a screen, sprayed again over the bottles.

Conveyor Belt

The conveyor moving forwards exerts a force onthe bottle causing a forward momentum

depending on the force exerted, the weight of the

bottle and the friction between the bottom of the

bottle and the conveyor. The higher the friction,

the higher the force exerted on the bottle. Holding

the bottle in place requires a counter force

equivalent to the forward momentum.

Packaging

After labelling, the beer bottles are sent for packing with the help of conveyor belt. Six bottles

are put in each box mechanically. After this, the box is sealed and stored, which is later on

transported.


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Ancillary Operations of brewery

Boiler Plant Cooling Plant Recovery Plant Waste Water Treatment Plant

Boiler Plant (source of steam)

Boiler is the main steam source in the brewery. In UBL, Ludhiana Rice Husk Boiler is usedfor the production of steam. Here,instead of using any fossile fuels , rice husk is used. Rice

husk is cheap fuel and easilyavailable. It produces less pollution. Firstly, we heat sand with

the help of coal upto temperature of 800 . The heated sand is fluidized with the help of airand is brought in contact with rice husk. The burning rice husk heats the water pipeline and

converts water into steam, which can be used for various purposes in brew house. The

combustion of rice husk leads very high burnt particles. To avoid emission of burnt particles

to the atmosphere, the cyclone separator is used.


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Cooling Plant

Ammonia is the primary refrigent used in the brewery and glycol is used as secondary

refrigent used. Propylene Glycol is a food grade antifreeze. The glycol, mixed with city

water, enables us to operate our chiller systems in the 25-27 temperature range thatbreweries require.

Plant

A Carbon dioxide recovery plant consist

1. Foam separator

2. Carbon dioxide gas container

3. Gas scrubber, carbon dioxide is freed from watersoluble impurities

4. Compressor, suck in the gas & compress it in two stages to liquefying pressure of 18 to 22

bar.

5. Cooler

6. Dryer, moisture still contained in the carbon dioxide is removed.

7. Carbon filter, undesirable aroma compounds still present are absorbed.

8. In the Carbon dioxide liquefaction unit the compressed carbon dioxide condenses at thelow temperatures produced by a cooling plant.

9. The liquid is then stored in a carbon dioxide storage tank from which it can be removed

again for immediate use in the brewery.

Water treatment Plant

The quality and quantity of brewery effluent can fluctuate significantly as it depends on

various different processes that take place within the brewery. Organic components in

brewery effluent (expressed as COD) are generally easily biodegradable as these mainly

consist of sugars, soluble starch, ethanol, volatile fatty acids,etc. This is illustrated by the

relatively high BOD/COD ratio of 0.6-0.7. The brewery solids mainly consist of spent grains,

kieselguhr, waste yeast and hot trub. Brewery effluent pH levels are mostly determined by the

amount and type of chemicals used at the CIP units (e.g. caustic soda, phosphoric acid, nitric

acid etc). The waste water released after the manufacturing process is treated at the Effluent

Treatment Plant which is located within the plant. The treatment process takes 6-7 days on an

average and the treated water is utilized for cleaning purposes. Among biological treatment


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systems one can distinguish between anaerobic and aerobic processes. Anaerobic treatment

is characterized by biological conversion of organic compounds (COD) into biogas (mainly

methane 70-85 vol% and carbon dioxide 15-30 vol% with traces of hydrogen sulphide).

During aerobic treatment (air) oxygen is supplied to oxidize the COD into carbon dioxide and

water. Both biological processes produce new biological biomass (bio solids)


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References

Books

Handbook of Brewing - F.G. Priest and Graham G. Stewort Handbook of Brewing -William A. Hardwick

Web-sites

www.alabev.com/brew www.beer-brewing.com www.brewingwithbriess.com www.documentationemersonprocess.com www.howtobrew.com www.nironic.com/wort_boiling.asp www.springerlink.com www.sterkensbrew.be/sbm/beermaking
http://www.alabev.com/brewhttp://www.beer-brewing.com/http://www.brewingwithbriess.com/http://www.documentationemersonprocess.com/http://www.howtobrew.com/http://www.nironic.com/wort_boiling.asphttp://www.springerlink.com/http://www.sterkensbrew.be/sbm/beermakinghttp://www.sterkensbrew.be/sbm/beermakinghttp://www.springerlink.com/http://www.nironic.com/wort_boiling.asphttp://www.howtobrew.com/http://www.documentationemersonprocess.com/http://www.brewingwithbriess.com/http://www.beer-brewing.com/http://www.alabev.com/brew


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