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SUBMIT ED BY: JITENDRA SINGH VERMA
B-TECH, BIOTECHNOLOGY
COLLEGE OF ENG. & TECH.
IILM, AHL Gr.NOIDA



A CHRONOLOGICAL PROFILE OF MOHAN MEAKIN

The history of mohan meakin goes back as far as the Lucknow DISTILLERY which although officially established in 1855 was probably has its existence in 1820. The evidence is in the form of bricks dated 1820 were discovered during maintenance work some years ago.

In 1855, an Englishmen named EDWARD DRYER established a brewery at KASOULI and gave INDIANS first thrills of the modern beer. Riding on the wave of his successful venture, DRYER went on to start distilleries at SHIMLA, SOLAN (both in HIMACHAL PRADESH), LUCKNOW MANDALAVA, BURMA. During this time another Englishmen H.G.MEAKIN who bought the old SHIMLA and KASOULI breweries and constructed
others at DALHOUSIE, RANIKHET, CHAKARATA, DARJEELING and KIRKEE.

Both these firms DRYER & Co. and MEAKIN & Co. continued separate business dealing till 1920's. During World War I, when importing beer was a hard task, after the First World War the two firms merged together and formed DRYER MEAKIN & COMPANY. In 1935, when BURMA was separated from INDIA, the company was recognized with its Indian assets and named DRYER'S MEAKIN BREWERIES LIMITED. In 1947, when India got its independence the company went through a major change in its management. Padamshree late N.N.MOHAN the founding father of MOHAN MEAKIN HOUSE overtook its management. In 1967, DRYER MEAKIN
BREWERIES LIMITED was named MOHAN MEAKIN BREWERIES LIMITED under the leadership of late N.N.MOHAN.

In 1969, due to passing away of Mr. N.N.MOHAN his eldest son COL. V.R.MOHAN took over as the managing director of the company. He introduced a number of new products that are grand leaders even today.

In 1973, after passing away of COL V.R.MOHAN, BRIG. KAPIL MOHAN became the managing director of the company. Under his guidance, the manufacturing activities of the company were diversified into other fields. Subsequently, in 1982, to remove the impression that the company is engaged only in beer making, the brewery word was dropped from its name.

Now, MOHAN MEAKIN LIMITED entered the international market and started exporting beverages to many countries such as U.S.A., U.K., JAPAN, and WEST EUROPEAN COUNTRIES & MIDDLE EAST. The company also began of man power & technical knowledge overseas especially where collaborations existed. A distillery and a glass factory were set up by MEAKIN PERSONAL at NAIROBI & KENYA a breweries set up in NEPAL & BHUTAN.
Apart of liquor, the other MEAKIN products which began for good profile were mineral water, cornflakes, mango nectar & apple juice.
Among the company's diversification plans there are proposals to enter the cement, steel metal & allied products. It was there transformative inclination that leads the company to rename itself in 1982 as MOHAN MEAKIN LIMITED.

A saga that began over a century and half ago continues on its path of service to the nation with dedication, courage and unflinching commitment to quality. Over the years the company has embraced modernity and adapted to changing times. Yet its basic values remain the same integrity, craftsmanship, tradition.
INTRODUCTION


There are two types of distilleries:
1. Potable
2. Non potable

Potable: The distillery which produces first of all alcohol in the form of spirit etc. and then after maturation blending is done to make liquor. M/s MOHAN MEAKIN LIMITED, LUCKNOW is leading manufacture of beverage of the sort country liquor, foreign liquor, beer and denatured spirit. Hence this is a potable distillery.

Non Potable: In non potable ones distillery only alcohol is manufactured in the form of spirit etc.

Lucknow distillery is one of the manufacturing units of Mohan Meakin Limited. It was set up by the Dyer Meakin and Company in the historic city of NAWABS (Lucknow) on the perennial river Gomti. The distillery is housed in a building built about 480 years back by the Nawabs of Awadh which covers a carpet area of about 1 sq. km. approx. It is located at DALIGANJ, 10 k.m. far from LUCKNOW central railway station.

Molasses is used as a raw material here. This is processed through different channels (prefermentation, fermentation and distillation) for the formation of alcohol.

Rail and road are the two modes of transportation used here. The nearby located sugar factories supply molasses to it. It has two separated storage tanks. One located near the city station acquiring molasses through rail and other one is located in the factory storing molasses through road transportation.

Alcoholic beverages manufactured are of two types:

1. Undistilled beverages: beverages produced after fermentation and purification and no distillation is done after fermentation is called as undistilled beverages. These beverages have low alcohol content. E.g. beers, champanege, cider, port, sherry.
2. Distilled beverages:
if the fermented liquid is distilled then they fall in this category. These beverages have high alcohol content as high as 50%. E.g. whisky, brandy,rum,gins.

The processing of molasses produces large quantity of liquid effluent called 'SPENT WASH'. The treatment of spent wash takes place in the EFFLUENT TREATMENT PLANT.

The units of MOHAN MEAKIN LIMITED as follows: SOLAN : Brewery, Distillery and Bottling.
KASAULI : Distillery.
LUCKNOW : BREWERY, Distillery and Bottling.
MOHAN NAGAR : Brewery, Distillery, Glass factory and Fruits production.

FERMENTATION

Introduction


The fermentation is derived from the Latin word fervrve, which means boiling. However, events of boiling came into existence from the fact that during the alcoholic fermentation the bubble of CO2 gas bursts at the surface of boiling liquid and give the watery appearance.

The action of specific micro-organism on a complex organic substrate and degrade it to produce the desired chemical compound is termed as Fermentation.

The majorities of processes require oxygen and classified as Aerobic. The other few processes carried out in the absence of air are classified as Anaerobic.

Fermentation process utilizes microbiology in producing chemical compounds. The process involves addition of a specific culture of microorganism to a sterilized liquid substrate or both in a well designed gas liquid contraction and carrying out the fermentation to grow micro-organism.

The general equation of fermentation is as follows:

Substrate + Micro-organism ==== More microbial cells + Metabolic products
Raw materials

The raw materials employed are among the most important materials of production process, to a large degree they determine the economics of the process, the production method and the quality of the product. Raw materials are naturally occurring substances utilized manufacturing industries. A fermentation substrate must be readily available throughout most of the year. Raw materials produced seasonally are not desired to have contamination and spoilage. Thus many industries need a substrate which is relatively stable and stored for 6 to 9 months without decomposition. Apart from bagasse, pulp and molasses most of the raw materials produced in sugar factory as are intermediated products of the sugar recovery process which are subsequently treated to crystal sugar. For cost reason, the use of non refined carbohydrates substrate often becomes mandatory in bulk fermentation. Thus less pure crystal sugar (after product sugar, raw sugar) or even sugar containing raw materials seems to be advisable.

Transport cost have to be taken care of, they become significant and prohibitive if too much is present and will prohibit the use of some waste materials at sites removed from their place production.

Some of raw materials are listed below:

1. Sugar crop:

1. Sugar cane: Although sugar cane is grown primarily for sucrose production, it is also used as raw material in alcoholic fermentation. The fermentable carbohydrates, from sugar cane may be directly utilized in the form of cane juice or in conjunction with a sugar factory from a black strap molasses.
2. Sugar beets:
as for sugar cane, beat molasses is generated in large volume from sucrose recovery operation. These raw materials contain sufficient nitrogen, other organic and inorganic nutrients such that, if any, fortification is required for fermentation.


2. Fruit crop:


Fruit with high fructose and sucrose content are grapes, peaches, apricots, peas, pineapples and apple.
3. Starches:

A variety o starches can be used for ethanol production by fermentation.
1. Corn: According to Miranowski(1981) corn is the most viable feed stock for the manufacture of ethanol in United States.
2. Cassava: Also called Manioc or Tapioca is cultivated in many tropical countries. Brazil, Indonesia and Zaire are the most important producers. It has starch content of 20-35 wt% and 1-2 wt% protein.
3. Sweet potato: Sweet potato powder (S.P.P.) generated by freeze drying, then grinding and screening the tubers. It has starch content of 64.4 wt%.

Keeping all facts in mind, black strap molasses are economically feasible and best result oriented in alcohol industries. So, widely used in INDIA.

Molasses: Molasses is generally used because it is rich in all salts except nitrogen which is normally employed in the actual growth of yeast cells.

It is defined as it is waste product of sugar industry of which further extraction of sugar is uneconomical.

Hence molasses is a solution of sugar, organic matter and inorganic matter in water. Even if all known components of molasses were added synthetically the result would not be molasses. Thus in accordance with the statement of three experts of sugar analysis nobody really knows what molasses exactly is?

We can say that molasses are the final effluent (final molasses) and byproducts of sugar manufacture. Due to their origin sugar cane and molasses are different. Black strap molasses are molasses produced from raw sugar factories from cane or beet. Often only term molasses is used for molasses from a beet factory where as black strap is preferably used for cane molasses.

Refinery (final) molasses (refinery black strap, barrel syrup), is derived mainly from cane refineries, where (high grade) white sugar is produced from raw sugar.

General composition of cane molasses: Molasses is an agricultural product and its composition varies with the variety of maturity of cane with the climate and soil condition. In addition processing condition in the sugar factory may also bring about changes in the composition of molasses. So, only average values of main components of cane black strap molasses given below.

Composition percentage
Sugars 73.1
Sucrose 45.5
Invert sugar 22.1
Other 5.5
Organic 15.5
Glutamic acid and pyrollidine carboxylic acid 2.4
Other N 3.1
Organic acids 7.0
Pectin etc. 2.7
Inorganic 11.7
K2O 5.3
Na2O 0.1
CaO 0.2
MgO 1.0
SO2+SO3 2.3
P2O5 0.8
Others 0.9

Physical characteristics of molasses: Molasses is a dark reddish colored jelly like viscous material. The pH of molasses varies from 6.8 to 8.5. The high osmotic pressure of molasses protects it from microbial spoilage, and it can be easily transported by barge and tankers etc. Molasses can be pumped easily. For production of ethanol in non sugar producing areas, and particularly in areas with suitable waterways for barge shipment, molasses may be the best suitable raw material for fermentation.

Classification of Molasses: Molasses are classified into following three grades:
a) First grade Molasses: It contains more than 50%TRS.
b) Second grade Molasses: It contains 40%to 50% TRS.
c) Third grade Molasses: It contains less than 40% TRS.
Responsible Micro-organism for Alcoholic Fermentation

The choice of fermentation micro-organism for industrial alcohol production depends on the type of carbohydrate present in the medium.

Yeast is usually used in alcoholic fermentation. Many yeast strains present, which are responsible for alcoholic fermentation. Some of them are listed below.

Saccharomyces Cerevisae Saccharomyces Ellypriodes Saccharomyces Carlbergensis Saccharomyces Fragillis Saccharomyces Oviformis Saccharomyces Saki

Saccharomyces Cerevisae is the yeast strain now a day used widely in alcoholic fermentation because of having many of properties listed below:
1. High ethanol yield
2. Osmotolerance
3. High growth & fermentation rate
4. High temperature fermentation Low pH fermentation optimum
5. Ethanol and glucose tolerance
6. General hardness under physical and chemical stress.

High growth and fermentation rate allows the use of fermentation equipment. Ethanol and glucose tolerance allows the conversion of concentrated feeds to concentrated products reducing energy requirements for distillation and spillage handling.

Osmotolerance allows the handling relatively 'dirty' raw material, such as black strap molasses with its high salt content.
Low pH fermentation combats contamination by completing organism. High temperature tolerance simplifies fermenter cooling.
General hardiness allows yeast to survive both the ordinary stress of handling such as centrifugation as well as arising from a plant upset, the improvement process consists of modification to the medium & fermentation conditions used, So as to increase the yield of end products. Other common method is mutation brought about by exposure of organism to

Ultra-violet Radiation
X-rays
Chemicals such as Nitrogen, Mustard etc.

Cultures are to be preserved so as to ensure their viability and reproducibility from batch to batch. They are lyophilized or kept on Agar improvement of micro-organism for industrial purposes.
Some of micro-organisms used in alcoholic fermentation are as follows: Bacteria
Zymomonas mobilis Clostridium actobutylicum Sarcina ventriculi Leuco-nsotoc mesenteroides

Fungi

Aspergillus orygae Endomyces lactis Nurospora crassa Rhizopus SP
Mucor SP

In spite of these fungi and bacteria, yeast group is most widely used in fermentation process.
Media for Fermentation

The principal media for the commercial production of fermentation involves following:

Molasses: the main raw material is the wastes produced in the sugar mills. It is a dark brown color viscous syrupy liquid obtained as a byproduct in both by vacuum pass process and khandsari process of manufacturing. The bulk of the supply is obtained by vacuum pass process. The molasses contains reducing sugar up to 50%.

Urea (NH2CONH2): Urea is added to fulfill the requirement of nitrogen for good fermentation.

Sulphuric Acid: Sulphuric acid is added to bring down the pH value to an optimum level (4.2 - 4.8). pH plays a vital role in good fermentation.

Yeast: Certain types of yeast strains are desirable which are able to produce and tolerate high concentrations of ethyl alcohol. It should also possess uniform and stable characteristics. The most popular yeast strain used for this purpose is Saccharomyces Cerevisiae.

Di Amonium Phosphate(DAP): Phosphoric Acid:
Antibiotic: To prevent the contamination (growth of other bacteria) an antibiotic Benzyl Penicillin is used.

Fermentation conditions

Temperature during fermentation 28-34 0C
Settling gravity of yeast vessels 1.045
Settling pH of yeast vessels 4.5 - 4.9
Settling gravity of prefermenters 1.05
Final gravity after complete fermentation 1.03 1.00
Duration of fermentation 24 hours
% alcohol after completion 5-8%

PROCESS


The process adapted in the manufacture of industrial alcohol is as follows:

Yeast Vessel: Yeast vessel is a metallic cylindrical vessel having capacity (1500 BL). It is mainly inoculums of S.cervisiae preparation tank. Inoculums preparation is a critical stage in an industrial fermentation process which usually differs in composition from production media. Inoculums media are compounded to quickly yield numbers of microbial cells in their proper physiological and morphological states, but without sacrificing genetic stability of the cells. The utilization of some component of the production medium i.e. molasses requires, the cells to be enzymatic ally adapted to this substrate, then this particular component should also be include in the inoculums medium. This precaution prevents deadaptation, if the cells already are adapted, or eliminates the leg period during the initial stage of production which may occur while adaptation is being accomplished. Here we are not interested in the accumulation of fermentation product other than cells in the inoculums medium and, hence, the inoculums medium is not balanced for product formation due to lack of carbon source.

Inoculum is prepared as a stepwise sequence employing increasing volumes of media. All steps, except that of initial inoculums from a stock culture, require the transfer of approximately 0.5 to 5% inoculums by volume from the preceding step in the sequence. At each step, the organism should grow quickly and in high numbers so that the period of incubation required is relatively short. Little, if any, fermentation product is accumulated during the inoculums stages, because the cells to be transferred their logarithmic growth phases and before accumulation of product would normally occur. In fact, inoculums media usually are balanced for rapid cell growth and lot for product formation.
Growth Curve of Yeast:


Prefermenter:

Here we are not concern with the alcohol production, we are concerned mainly with the growth of yeast culture and adaptation of cells in a large cylindrical metallic vessels having capacity 86230 BL. That's why low dilution is maintained to avoid alcohol formation for 7 to 8 hours in anaerobic conditions. The specific gravity of the medium is 1.050 and optimum temperature for the growth of S.cerevisiae is 300C but somewhat higher temperatures (35 - 380C) are tolerated. Yeast growth is inhibited by solution of high osmotic pressure and high concentration of ethanol. Molasses contain variable amounts of nitrate which can be reduced to nitrate by bacterial action during the production of yeast. A considerable loss in yield has been reported for concentrations of 0.004 to 0.001% nitrite.

Many products have been reported to be activators or inhibitors of yeast growth. Flour milling waste, sludge from aerobic digesters etc. are considered as activators while SO2 inhibits yeast growth but concentrations up to 800 ppm molasses can be well tolerated. S.cerevisiae adapts well to the presence of even higher concentrations of SO2 as is known from the use of this species in the wine industry where fermentation is often carried out in the presence of 80 to 100 ppm of SO2.


Fermentation:

Fermentation applies to both the aerobic and anaerobic metabolic activities of micro organisms in which specific chemical changes are brought about in an organic substrate due to the enzymes secreted by those microbes.

Fermentation is the core part of distillery which is carried out in large cylindrical vessel generally made of stainless steel having thickness 5-6 mm and capacity (46300 BL) is called as fermenter. The media which has been prepared is introduced in the prefermenter and after 7 - 8 hours it is transferred into fermenter where fermentation is carried out. Here batch fermentation is carried out without establishing pure culture conditions and without maintenance of complete sterility of equipment. However, this pre supposes a rapid start of the yeast fermentation. This fermentation inhibits the growth of other microbes by depleting the available nutrients, by lowering the pH and most importantly by the formation of ethanol. To reduce the pH H2SO4 is usually added.
Reactions in the fermentation:

As we know molasses contain approximately 50% invert sugar i.e. sucrose. It is converted into glucose and fructose in the presence of yeast and invertase enzyme.