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PROJECT REPORT ON STATISTICAL QUALITY CONTROL
Company Name- Britannia Industries Ltd. Delhi
With the Special Reference of-Bhagwati Foods Pvt. Ltd;Part of Arazi No. 1618,N.H.No-2, Sachendi,Kanpur-209304
Submitted to-Britannia Industries Ltd.,33, Industrial Area Lawrence RoadDelhi-110035
Under the Guidance of- Submitted by- Md Zeeshan Israr
Mr. Amit Arya B.Tech. Food Tech 4th Sem.
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PROJECT ON BISCUIT
Project Contain of the Following-
Introduction of Biscuit Ingredients use in biscuit Wheat Flour Composition of Wheat Flour Leaveners Chemical Leavening System Sodium Bi – Carbonate Typical Analysis of Sodium Bi – Carbonate Leavening Acids Ammonium Bi – Carbonate Folic Acids Fat and Oils Function of Lipids Chemical properties of Lipids Sweetened Condensed Milk Emulsifiers Lecithin Preparation of Lecithin Paste Antioxidant Synthetic antioxidant Natural Antioxidant Sweeteners and Syrup Sucrose and invert Sugar syrup Water Water Standard Salts Analysis of Salts Bulk Handling of Ingredients Recommended Storage Condition Pneumatic Transfer Principles Automatic Batching System Mixer &Mixing Horizontal Dough Mixers Sheeters Rotary Molding Machine Oven and Baking Baking Time of Biscuit Heat Transfer Mechanism
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Packing Equipments Study of Packing Machine and Its Efficiency Packing Material Standard of Packing Material General Safety Rules Sanitation Assignment Study of break down Time of Plant Check Weight of Biscuit Packet Flow Diagram of Processing
Assignment in Lab
Determination of Moisture Content by Air Oven Method Wheat Flour Moisture
Determination of gluten in wheat flour Determination of alcoholic acidity in wheat flour Free fatty acid in oils / fats Estimation of ash content Determination of acid insoluble ash Determination of sulphated ash Purity as acetone insoluble in lecithin Determination of benzene insoluble matter in lecithin Test method: sodium Meta bi sulphite (smbs) Determination of fats: Estimation of Peroxide Value Kries test Presence of TBHQ in oils & fat Determination of melting point of solid substances Granularity in wheat flour Determination of sedimentation value in wheat flour Testing of corrugated paper/corrugated Board
Biscuit3
Biscuit is eaten by all the people worldwide. It is consumption urban semi- urban and rural area etc. It is industry located at which area where market close.
In the united state of America, biscuit may mean the equivalent of the English muffin, thence another word enters the vocabulary – cookie. (English dictionaries mostly state that the derivation of word biscuit is the Latin bis coctus via the French bi-cuire-to cook twice.)
A ships biscuit is defined as ‘an old established coarse kind of biscuit used at sea as a substitute for bread. This is obviously what is inferred in walker’s Dictionary (Londan 1848) which state: Biscuits, a kind of hard. Dry bread, made to be carried to sea: a composition of fine flour, almonds and sugar’.
Digest Encyclopedia Dictionary (Canada, 1966) defines ‘biscuits’ as ‘a kind of crisp dry bread, more or less hard, variously flavored and usually unleavened, prepared usually in small, flat, thin cakes.
Obviously none these definitions meets with every one’s approval.
With such semantics let us now try to give our own definition or specification of biscuit.
It Shall:
Be based on a cereal content wheat, oat, maize, barley, Soya, rye etc. Contain less than 5% moisture. If decorated with a non cereal product (cream, marshmallow, icing, jelly, Jam etc.) The moisture present in the decoration shall not be considered in the 5%. Not be considered a biscuit when more than 60% of its total weight is not cereal based. Be considered a biscuit if so called by custom, habit or tradition. Biscuit and cookie shall be deemed synonymous.
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“Quick bread with a ratio of about 3:1 (flour to liquid) and also containing fat, cut into small particle, baking powder and salt usually kneaded and rolled but some time dropped.
It’s processing very easy and convenient firstly word biscuit term used by Christopher Colombus Who discovered America.
In U.S.A. firstly termed as jumbo, pluckets and cry babies.
In 19th country, sugar, wheat flour and baking soda priced very down so, its comes in to market.
Britannia Industry formed two types of recipe. CakeBiscuit
CLASSIFICATION
Different types of biscuits are given below.
Hard biscuit-Less gluten development in to dough called hard biscuit.
Soft biscuits-more gluten development in to dough called soft biscuit.
Fermented biscuits- when flavour development by microorganisms
called fermented biscuit.
I am interested in project of biscuit because - It is less time takes processing.It is consumed more.It is available all over the world.Its shelf-life is long because moisture percent 1 to 2 %.
Many industries are coming in biscuit processing like ITC, Priyagold,
and Parle etc. So there are more job opportunities.
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Ingredients Used in Biscuit
Wheat Flour:
Wheat flour is the major ingredients of biscuit. It determines the finished quality of most bakery products. Among the reason for the strong influence of flour are -
Unique proteins in wheat flour give most bakery product a characteristic highly expanded structure.Wheat flour generally present in a larger proportion then any other ingredients.It follows that bakers must be certain the flours they are using have uniform properties appropriate to the products being made. Bhagwati Foods Pvt. Ltd is job worker of Britannia Industries Ltd. use Wheat flour from Triupati Roller Flour Mills Ltd. and its Brand is Ram Bhog Flour.
Composition of Wheat flour:
Protein:
The storage in wheat flour includes gluten, which is the complex mixture of nitrogenous compounds that gives wheat flour dough their cohesive and elastic properties. Gluten can be separated form wheat flour by making by stiff dough from a mixture of flour and water, then washing until the starch granules and all soluble materials have been removed.
Protein Class Solvent % of total nitrogen Globulin+albumin Nacl in water 12-18Gliadins 70%ethanol 20-43Glutenins Acetic acid 6-12Glutenins Hgcl 19-28Glutenins 2-mercaptoethanol 10-27
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Carbohydrate :
Carbohydrates are formed from Co2 & H2O by the process of photo synthesis it act as energy source. Mono and disaccharides are found in wheat flour but they are present in very small amounts.
Ash % of dry matters, the following values may be considered fairly represents:Fructose 0.06%, Glucose 0.08%, Galactose 0.02%, Sucrose 0.54%, difructose 0.26% and maltose 0.05%. Sugar of high molecular weight ex raffinose 0.19%.
Lipid:
In wheat flour lipids are present in the form of free fatty acid, simple glycride, glactosyl glyceride, phospo glycride, sterol lipids, sphingolipids, diollipids, tocopherols, carotenoids, wax esters, and hydrocarbons, In amount, the principal lipids are acyl lipids containing the fatty acids palmitic, stearic, oleic, linoelic, and a- linoenic, Reports have indicated minor amounts of many other fatty acids.
Enzymes:
Wheat flour contains a larger number of proteolytic enzyem, such as endoproteolytic enzymes and exo proteolytic enzymes. The acid carboxypeptidase, which are exoproteolytic enzyme reacting at carboxy termination.Phytase catalyzes the hydrolysis of phytic acid to inostiol and freeorthophosphate.
Wheat flour used in many chemically leavened product such as cakes, cookies, doughnuts, biscuits and pancakes.Wheat flour is structural and shape provided ingredients
Leaveners:
The rising or expansion of dough during some time of their preparation. The generation of CO2 for reaction going on within dough is the principal leavening force in the majority of bakery products like biscuits but in Britannia tiger and world food programmed biscuits used chemical leavening system not yeast fermentation. About 90 % of all chemical leavening system in bakery food involves the NaHCO3
with acid reacting ingredients.
Chemical Leavening System :
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Chemical leavening system in source of Gas, almost always NaHCO3 and one or more acid reacting substances. If these essential components are combined in a baking powder, other materials will usually be included to dilute the powder to standard strength, or for other purpose. The acid reacting substances are included to neutralize the alkalinity of the soda and to generate the maximum amount of CO2, when baked product is formulated for low sodium diets; NaHCO3 is some times replaced with KHCO3.
Acid reacting components may include ingredients that perform other function in the final mixture, such as molasses, fruit juice, and butter milk. The baker can also neutralize the soda with an appropriate amount.
Sodium Bi-Carbonate:
It is main leavened agent. NaHCO3 use as a leavener is based on its low cost, lack of toxicity, ease of handling, relatively tasteless end product, and High purity of commercial supply.
Typical Analysis of Sodium Bi- Carbonate :
Component % of totalCarbonates 99.8300Sodium Carbonate 0.7060Sodium Chloride 0.0071Sodium Sulphate 0.0012Sodium Sulphite 0.0005Silica 0.0010Iron Oxide 0.0070Aluminum Oxide 0.0023Calcium carbonate 0.0168Magnesium Carbonate 0.0015Other Substance 0.0637
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Advantage:
Its solution tend to be less alkaline for ex the carbonate so that localized region of high alkalinities are less apt to be formed around granules as they dissolved in dough when high pH a region are formed, undesirable colure and flavored spot may occur when the mixture is baked. Disadvantage:
NaHCO3 offered for ingredient use will yield 52.32% of the total weight as Co2 and contain 36.88 totals Alkali.
It also tends to deteriorate upon storage unless it can be kept very dry. A version of the powdered grade that has been treated with calcium phosphate
has the advantage of being free flowing and a particularly useful in self rising flour and packed mixes.
If sodium bi carbonate granules remain undissolved in the dough, they may decompose to the carbonate salt during baking. This results in excess residual alkalinity, which causes a soapy off taste and undesirable dark crumb color. Dark spots on the crusts and yellow spots in the crumb development if particles remain un dissolved at the time the dough inters the oven.
when sodium bicarbonate is dissolved in water, there results a mixture of sodium ions, carbonate ions, bicarbonate ions , un dissociated carbonic acid and dissolved carbon dioxide .proportions of last four components are determined by the temperature of the system, if the system are concentration of hydrogen ions, and the partial pressure of carbon dioxide over the solution .
Considerable amounts of carbon dioxide can exist in aqueous solutions above pH8.
Leavening Acids:
Function:
Leavening Acid is to promote a controlled and nearly complete evolution of gas from a dough in which carbon dioxide exists in its dissolved or bound form advantage.
Advantage:
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The acid must be nontoxic and must yield edible and nearly tasteless and products normal storage temperature. It should be economic any easy to handle. The phosphates and cream of tartar commonly used as leavening acids are actually matel salts of partially neutralized acids, while sodium aluminum sulfate (and some others) reacts with water to form acids.Sodium aluminum phosphate has a high neutralizing value and so is economical to use its reaction rate is relatively slow, but several grades differing in rate of gas release are available. Sodium aluminum phosphates have good buffering action leading to pH levels near seven in many systems.
Leavening Agent:
Leavening agents contribute significantly to the textural properties of baked products by expanding the batter or dough, sometimes during mixing and always during baking. Leave means to make light. These are added to the dough during the preparation of bakery products. i.e. the process of leavening refers to the increase in volume of dough when CO2 is incorporated in air. Chief sources are ammonium bicarbonate & sodium bicarbonate. They raise the product by expanding the dough during mixing & baking. Ammonium bicarbonate at 106 F releases NH3 & CO2. Gasses thus liberated aerate the dough; render it light, porous & gives right gauge &thickness to the biscuit.
Leavening agents are of three types:i. Mechanical leavening agents: Air, steam
ii. Chemical agents: Baking powder, Sodium bicarbonate
(Baking soda) , Ammonium bicarbonate.
iii. Biological agents: Yeast
i. Mechanical leavening agents
Air: Air is incorporated into the mixture during creaming stage.
Steam: Steam alone does not show the property of leavening to be used in
combination with air or CO2.
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ii. Chemical leavening agents
a. Baking soda: It is chemically known as Sodium bicarbonate. It will liberate
CO2 gas, a leavening gas, when heated.
2NaHCO3+Heat →CO2 + H2O + Na2CO3
b. Baking powder: Baking powder will start evolving CO2 gas as soon as the
product is placed in oven. Baking powder is combination of sodium
bicarbonate and an acid salt when moistened and heating will evolve gas,
which leavens the product.
c. Ammonium carbonate or bicarbonate: When ammonium bicarbonate is
heated, CO2 and NH3 are produced. No solid is left behind in this reaction. It is
used as leavening agent in baking biscuits and crackers as they have large
surface to mass ratio and ammonia escapes when baked at high temperature
Ammonium Bi-Carbonate:
Ammonium Carbonate and Ammonium Bi-Carbonate are used as leavening agents in applications where very low final moisture content is reached in the baked products.
When they are heated ammonium Bi-Carbonate and Ammonium carbonate the decompose completely in to ammonia, CO2, and water.Ammonium Bi- Carbonate generally use as a supplementary leavener. Temperatures above 1400 F will cause the rapid decomposition of dry ammonium by carbonate. A small amount (1%) of magnesium carbonate is usually added to powder as a flow agent.
Disadvantage:
When some ammonia may be retained in the food that reaches the consumer, it has disastrous effect on acceptability.
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Folic Acid:
Folic acid or folacin (Latin folium-leaf) is important for one carbon metabolism and is required for the synthesis of certain amino acids, purines and the pyrimidine- thymine. It is heamatopoietic and commonly called B9 .
Chemistry:
Folic acid consists of three components pteridine ring, p-amino benzoic acids (PABA) and glutamates acid (1 to 7 residues). Folic acid mostly has one glutamic acid residue and is known as pteroyl- glutamic acid (PGA). The active from of folic acid is tetrahydrofolate (THF or FH4). It is synthsized from folic acid by the enzyme dihydrofolate reductase.
Fat and Oil:
Those are esters of fatty acids with glycerol. The difference between fat and oil is only physical .Shortening is a word used to describe fats, oil that is ingredients in dough. Shortenings may contain substances other then fats and oils, for ex flavor, color and emulsifiers.
Fats and oils are their derivatives, are important ingredients in the baking industry. It lubricate the internal structure intermediates to allow greater expansion during proofing and they make the texture of finished product more tender.
Functions of Lipid: They are concentrated fuel reserve of the body (tryacyl glycerol).
Lipids are consistent of member structure and regulate the membrane permeability.Fats and oils are important as a heat transfer media in the frying of doughnuts and similar products.Fats and oils are indispensable in many adjuncts: topping, filling, icings, frosting, coatings etc.
Fats and food oils are tri glycerides of fatty acid, that is, three fatty acid molecule are chemically combined with one glycerol molecule to yield one molecule of lipid.
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Naturally occurring fatty acid almost always have an even number of carbon atoms between 4 to 26.
Fatty acid with more than three double bonds are apparently not found in food, except for some fish oils that contain 4,5,and 6 double bonds.Britannia Tiger use palm oil and palm kernel oil has received much attention as their supply increased and quantity improved in recent years. Palm and palm kernel oils are obtained form the fruit of oil palm. The fleshy covering of the fruit is processed to obtain palm oil while palm kernel oil is excreted from the seed that lies at the central. The quantity of palm oil entering international commerce has increased markedly during the pass decade, the quantity and uniformity of the products has improved substantially.
Chemical Properties:
Hydrolysis:-
Triacyl glycerol undergoes enzymatic hydrolysis to finally liberate free fatty acid and glycerol. The process of hydrolysis catalyzed by lipase is important for digestion of fat.
Sponification: The Hydrolysis of triacylglycerol by alkali to produce glycerol and shop is known as saponification.Triacylglycerol + 3NaOH →glycerol + Soap Rancidity :
Deterioration of fats and oils is known as rancidity. They give an unpleasant taste and order. Rancidity occurs when fat and oil are exposed to air, moisture, light, bacteria etc.
Antioxidant: The substances which can prevent the occurrence of oxidative rancidity is known as antioxidant.Trace amount of antioxidant such as tocopherols, hydroquinone, Gallic and alpha-naphthol are added to the commercial preparation of fat and oil to prevent rancidity.
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Sweetened Condensed Milk:
In processing sweetened condensed milk is not sterilized, but multiplication of bacteria present in this product is prevented by the preservative action of sugar.
The product is made from pasteurized milk that is concentrated and than supplemented with sucrose.
Sweetened condensed milk is use in baking, confectionery, ice-cream industry.
Emulsifiers:
Emulsifiers are natural or synthetic substances that promote the formation and improve the stability of emulsions ex dispersion of fat droplets in aqueous solution or of water droplets in a continuous lipid phase. In some case they can be used to improve wetting properties change the surface tension of water aqueous solution. Surface active agents are widely employed in the baking industry for these purposes. In britannia mixture of lecithin and solbake is used as emulsifier.
Lecithin: Greek lecithose means egg yolk.It may be natural and synthetics.These are the most abundant group of phospholipids in cell membranes.Commercial grade of lecithin are classified according to their total phosphate content, color and fluidity.The concentration of total phosphate in commercial lecithin product between 54 and 72%.
Lecithin is structurally like fat out contains phosphoric acid.If the oil is shaken in an excess of water the oil will form small droplets. Than the non polar ends of lecithin molecule orient themselves with in the fat droplet and the polar ends stick out from the surface of the droplet in to the water phase.
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Preparation of lecithin Paste Used in Britannia: Lecithin and Palm Oil are use in the ratio of 1:3 respectively. 100 Kg Lecithin + 300 Kg Palm Oil
Mix Homogeneously
Properties of lecithin paste
Tobacco and brownie color Soluble in Palm Oil
Preparation of solbake paste Used in Britannia
Palm oil, solbake and water is mixed in the ratio of 1.5 2 ׃1 ׃ ratio respectively and mixed homogenously.
Antioxidant:
All bakery food contents some fat even it is only % or so of lipid that is naturally present in flour. All of these fats including the flour subject to oxidative and hydrolytic rancidity with resultant undesirable flavor and color.
Antioxidant are materiel that can retard the development of oxidative rancidity during storage of food containing fat .Natural antioxidants are found in many food, including "no purified" fats such as unbleached cocoa butter, and certain chemical compounds can be added to fats to retard their deterioration .
In the development of hydrolytic rancidity, moisture and enzyme cause splitting of the triglyceride molecule into glycerol and free fatty acid .Hydrolytic rancidity can be controlled by inactivation of the responsible enzyme by sterilization, low moisture content, and low storage temperature.
Oxidative rancidity attacks the unsaturated portion of fatty acid, the double bond.
There is auto oxidation by a free radical mechanism catalyzed by heat, light and trace quantities of metal ions.
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Synthetic Antioxidant :
TBHQ or BHA is a synthetic antioxidant that has been used effectively for many years to protect the flavor of fat containing food.TBHQ is an antioxidant that has been approved by an FDA for use in food. TBHQ seems to be more protective than the antioxidant.
Characteristics of synthetic antioxidant
Common Name Melting range order Solubility % BHA 48-63 Slight 50BHT 70 Slight 30TBHQ 126-129 Very Slight 10
Natural Antioxidant:
Many substances naturally occurring in food and food ingredients act as fat antioxidant to some extent. They are usually of limit practical value for one or more of the following reason.They are of low potency.They are accompanied by flavors orders or colors that are undesirable in most food.They would be inordinately expensive to produce in commercial quantities.Their legal status as ingredients is questionable.
Sweeteners and Syrup :
The type of sweeteners most commonly used are sucrose (Cane or beet sugar) and various hydrolysates of corn starch (corn syrup, dextrose etc). Depending on the amount added, these ingredients can affect not only the taste but also the texture and appearance of the baked product.In addition to common types of nutritive sweeteners added to the food there are several other non nutritive sweeteners are added.
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Sucrose and invert sugar syrup:
In Britannia sucrose is use in bakery. Liquid sugar can be roughly classified sucrose type, invert sugar syrup. Sucrose is available at 66.5 % to 68 % solid contain. Totally
invert syrup content 72 to 73 % solid per have 5 % being sucrose. All of the syrup is reasonably resistant to micro biological spoilage, but the invert syrup is probably some what superior in this regard because of their lower water activity. There has been some controversy about the relative sweetness of sucrose invert.
It prevent crystallization of sugar, imparts flavor. Invert sugar has lower
caramelization temperature compared to sucrose. Thus, biscuit coloration takes on a
browner appearance more quickly. It is sweeter than sucrose. It is obtained by the
inversion process of sugar.
Sodium Meta Bisulphate:
It is a dough conditioner. It mellows down the gluten & relaxes dough. It breaks long tough
protein chains to short weak ones. It functions by donating hydrogen atom to disulphide bond in
gluten network thus converting it to sulphydral bonds. Thus, mellows down gluten making the
dough & thus desired shape of biscuit is achieved.
Water:
Water is a unique compound. it has been called the universal solvent water does dissolved so many other compound that obtaining a totally pure sample seems to be a practical him possibility.The chemical, physical and microbiological characteristics of ingredients water can have significant effects are the quality a bakery goods.The amount and types of dissolved mineral and organic compound that are present in the water can affect the color, flavor and texture of the finished product as well as response to machining of dough.
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The quality of ingredients water is established by the initial status of the water, the treatments applied to it inside and outside of the plant and the condition of storage and transport subsequent to treatment.Even dough are less sensitive to minor differences in water quality than are some other foods and beverages, this do not mean they totally lack response to fluctuations in this ingredients.
Water Standard:
The standards specify that the water supply shall be obtained from the most desirable source i.e. feasible, and efforts should be made to prevent or control
pollution at the source. If the source is not protected by natural means, the supply must be adequately protected by treatment.
Effect of Water Impurities on Bakery Products :
Variations of hardness with in the normal range found in potable water supplies have no hygiene significance; they do affect taste, response of foods during preparation, and suitability of water for industrial purposes such as steam generation.
The ions responsible for hardness can affect the color, flavor, and texture of food, and it may be necessary to remove them in order to improve the quality of finished products.
Hard water can increase mixing times, and have a retarding effect on fermentation.
Alkaline water is considered undesirable because it can neutralize the acidity develop fermentation, this being an important factor affecting dough quality.
Salt:
Salt is essential nutrient. It provides a salty taste. It is made up off sodium ion and chloride ion. Neither the sodium ion nor the chloride ion alone causes the typical salty flavor. Substances other than sodium chloride any provide a similar flavor. Some salts are more or less toxic and so or not suitable for food. All other taste inducing substances in food, such as sucrose or acetic acid, bind to receptor one of
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the hundred are so taste cells present in every taste salt generate in pulses that are conducted to the brain and recognized as sweets sour and bitter.
Analysis of Salts use in Britannia (supplier Adita salts):
Appearance - Snow White Particle Size - 150 to 850 micron 90% minimumMoisture - 0.30%
Chemical Analysis (On dry basis)
NaCl - 99.29100%Water insoluble - 0.031%Calcium (Maximum) - 0.22%Magnesium (Maximum) - 0.10%Sulphate - 0.49%
Iodine content - 30ppm
Sodium is an essential nutrient. Symptoms related to sodium deficiency in the diet are rare because the widespread presence of food. Sodium chloride modifies other flavors. It is use as a preservative.
Salts substitute in bakery product:
The concentration the salt in dough affect a number of processing response but the main bakers use this ingredient in its enhancement of the flavor of the finish products replacement for sodium chloride has been offered as basis for formulating products. Potassium chloride is probably the most binding used salt substitute.
MANUFACTURING PROCESS FOR BISCUITS :-
I) Receiving of ingredients :
1. Raw material comes as per purchase order given by Mumbai office and as
per requirement comes at factory.
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2. Testing by laboratory: Only after pass, raw material is unloaded and store
in storage section.
II) Premixing of ingredients & flour sieving, Biscuit Grinding:
1. Creaming:
Sugar grinding, preparation of invert Syrup, Vanaspati, Biscuit dust,
Chemical preparation
2. Mixing :
Charging of ingredients, addition of flour and mixing. Removal of dough in
dough trucks.
3. Moulding:
Dough crushing, conveying, metal detection, moulding, extraction on web &
panning.
III) Baking and cooling:
After moulding the dough, dough is passed through hot air oven in certain
baking time.
After baking the hot biscuits travel through cooling conveyor in natural air for
getting solidification. Then biscuit comes to stacker, where it get arranged in rows
for packing.
IV) Packing and Dispatch:
After that biscuits are packed in semi-automatic wrapping packing machine in
a certain temperature. Then these packs are filled in polybags and then in CBB. CBB
goes to BSR for storage and further checking procedure.
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All finished products are checked by a panel of directors, Britannia officer and lab.
Chemist for dispatch clearance also called as test evaluation. .
Flow Diagram of Processing
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RAW MATERIAL
CHECK VEHICLE CONDITION
RECIEVED IF CORRECT
STORAGE
ISSUE
MIXING
MOULDING
BAKING
COOLING SECTION
PACKAGING
STORAGE (FINISHED PRODUCES)
DISPATCH
MIXING DEPARTMENT
This department consists of dough mixers, invert syrup preparation tank,
cream mixer.
I) Dough Mixer
A. Application:
The machine is used for mixing various ingredients such as flour, sugar, fat,
water, and other chemicals for making hard, soft or fermented
dough for making biscuits.
B.Design:
A base plate over which two side frames are fitted for taking the load of
mixing chamber which is fitted on side frames. In the mixing chamber two Z/sigma
type-mixing blades are fitted which rotate at different speeds in opposite direction to
mix various types of soft/hard dough for achieving required glutton of dough. An
electrically operated tilting device is also fitted to tilt mixing chamber to unload
mixed dough. The machine is covered from all sides to avoid dust and accidents etc.
Mixing Process
Although the main purpose of mixing is to intersperse the ingredients into
each other, it must be carried out in a series of sequential steps as follows.
1) Creaming:
This step involves mixing of fat, antioxidant, sugar, invert syrup, flavour, biscuit
powder & emulsifier at a high speed (60 rpm) for 7 min . The purpose is to mix fat,
antioxidant, & emulsifier and to entrap air in the fat molecule.
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2) Wet mixing
Here, all the required remaining chemicals soda, salt, ammonia, etc are
dissolved initially in required quantity of water in special mixer for 4-5 min. Then,
this solution is added to mixing bowl & allowed to mix for 3 min.
3) Dough Mixing: -
Finally flour & in some variety, SMBS is added at last, & allowed to mix for
4-6 min., Mixing time is adjusted to have desired gluten network. If mixing time is
less, then gluten network will not be developed. If mixing time is more a weaken
dough formed & then break due to excessive mechanical action .This is because
weak flour has lower mixing tolerance.
During mixing, gluten in wheat flour forms linkages between protein molecules.
These linkages form 3-D structure, which provide strength to the dough. Thus,
dough can be stretched in all direction under pressure of gas.
SMBS is added during mixing, it provides height and good dimension to the biscuit.
Silo tank
It is a jacketed stainless steel cylinder with concentric rotating shaft having a
scrapper. Chilled water is passed through the agitator jacket & palm oil inside the
cylinder. The layer of oil in contact with the inner wall is immediately solidified into
fine crystals & immediately scrapped off by a scraper reincorporating them to oil as
the oil passes along the cylinder. The proportion of solid fat crystals increases & so
increases viscosity .It is ejected from the cylinder into automatic weighted tank. This
tank transfers automatically the required quantity of palm oil to mixer at creaming
stage via pipelines.
III) INVERT SYRUP PREPARATION TANK:
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It is a cylindrical tank having a short three bladed impeller rotating at a high-
speed. It is placed off centered with the shaft at some angle to the vertical, which
facilitates the mixing. It is having the heating coil at the base & adjustable
temperature knob. It is connected to a series of four storage tanks, which are used for
storage of invert syrup. They are arranged so that first tank will contain cold invert
syrup.
IV) Chemical Mixer:
It is a small cylindrical tank it contains short three bladed impellor placed off
centre & rotated at a high speed. It is used for mixing all chemicals (soda, ammonia,
salt etc) in water.
MOULDING AND BAKING
(1) Moulding :
The dough from the mixer is dumped into a dough truck of 300kg capacity. It
is then carried to the hopper. The dough track is fitted to a dough lifter, which lifts
the dough truck, adds the dough to hopper. During feeding dough gets resting time,
which is essential to reduce stress in the dough.Excessive retention, time will make
the dough dry & crumbly.
Both the hoppers are fitted with dough breaker, which helps to aerate the
dough. The broken dough is passed through a metal detector, which detects the
metal pieces in the dough. If metal is present then dough conveyor is stopped
automatically. The dough conveyor then feeds the dough to the hopper of Rotary
Moulder for forming operation.
Forming Operation:
Rotary Moulder is used for forming the biscuit. Three large diameter rollers
are placed in a triangular formation. The upper two rolls consists of a heavily
grooved “forcing roll” which pulls the granular dough down from the small hopper 24
& forces it into biscuit sized impressions in the engraved rollers. At the narrowest
point between the two rollers, there is a knife, which scraps any excess of dough
remains on the forcing roll & returns to the hopper. Beneath the engraved roll is the
third ‘extract roller’. This is covered with thick rubber to make it resident & drives
the endless web wrapped round it. The extract roller on the engraved roller applies
the pressure & this causes the dough in the cups to adhere preferentially to cotton
conveyor. Biscuit thickness can be altered by
- Moving forcing roll closer or away from engraved roll;
- Altering vertical position of knife;
- Altering pressure of extract roller on the engraved roller.
The dough pieces from endless conveyor are transferred to a panner web,
which moves ahead for a short distance & transfer dough pieces to oven band.
(2) BAKING PROCESS :
“Baking is a process in which a series of physicochemical changes occur in
addition to the removal of moisture by means of heat transfer, i. e. conduction,
convection and radiation.
The term baking simply means heating the dough in an oven.
The oven is indirectly fired oven with furnace oil as an energy source.
Principle of Indirect Heating :
Heat is applied to the biscuit through heat exchanger, The products of
combustion being isolated from food. In a combustion chamber, furnace oil is
exposed to air, which is brought by circulating fan, & there is a transformer, which 25
gives some fire to the mixture, & thus flames are generated in burner. Therefore, it
heats the air. Thus, air acts as heat transfer fluid. This heated air enters into iron
tubes, which are fixed, to top &bottom of band. The heated pipes acting as a heat
exchanger, transfers the heat to the biscuit principally by radiation & convection &
also by conduction the products of combustion are ejected to atmosphere through
chimneys.
Radiation mode of heat transfer occurs directly by energy waves from heating
tubes to the biscuits. Along with circulating fan there are turbulence fan, which
circulates the heated air within oven chamber. This air is also get heated by the
heating tubes & oven environment. Thus, transfer the heat to the biscuit by forced
convection. This also tends to sweep the biscuit & reduces humidity near the
surface. The main heating by the conduction is from the hot oven band into the base
of the biscuit.
The Baking Oven:
The baking oven is constructed into a series of blocks to allow for the
expansion of metal due to heating & is separated into seven distinct zones. The
baking oven is internally coated with thick glass wool insulation to avoid heat loss &
to improve oven efficiency.
The oven band is simply a continental wire mesh containing series of
interlinked spirals. The significant air spaces between the meshes of the wire allows
free access of heat to the dough from beneath & free exhaust of steam from the
underside of the dough. The spacing of the dough pieces on oven band is important.
The spacing should be such that to allow for the expansion during baking which
would otherwise result into a joint biscuit.
26
OVEN CONTROL:
Baking time:
It can be increased or decreased by decreasing or increasing moulders rpm &
oven band speed.
Baking temperature:
It is controlled by heat controller, also controls top, & bottom turbulence.
Humidity & Pressure:
Steam is released as result of removal of moisture from dough. If the chamber
is devoid of opening, it will create a humid environment & build up a pressure inside
the baking chamber. Steam dampers can control humidity & pressure; minimum
opening will result into humid oven & vise versa. It is the case with the build up of
pressure in baking chamber. Damper control is essential to obtain desired spring of
dough piece at right place & time during passage through oven.
Damper is closed to -
-Prevent drying out quickly.
-Building up some pressure outside to delay the engross of moisture & gases
of the dough until texture is formed.
-Reduce burnt edge effect.
Dampers are kept open to -
- Reduce undue pressure on dough surface
- Allow oven gasses to escape.
27
CHANGES OCCURS DURING BAKING
The dough pieces in the oven under go two types of changes:
- Physical changes, Chemical changes
Physical Changes:
A).Formation Of Film Crust on Dough:
On entering the oven, the outside of the dough piece soon becomes coated
with a film or crust, the thickness of which develops as moisture evaporated from
the outsides film. This crust formation starts as slow temperature as 100°F &
precedes rapidly around 190°F. The degree of elasticity attained is a direct function
of the moisture content or humidity of the oven atmosphere, particularly in the first
two zones of a seven zone oven.
b) Melting Of Fat in the Dough:
The aggregates of fat particle melt as soon as their intermediate area in the
dough pieces reaches the melting fusion or slip point temperature of the fat structure.
Whilst some portion of the fat, the lower melting point fractions will seep into
enveloping
structure, the pockets of fat will remain more or less within their original position in
the dough structure .Thus contribution of fat to biscuit texture.
c) Gas Expansion:
The CO2 formed by chemical reaction within the dough pieces under the
influence of increasing temperature will increase the volume, &stretch the dough
piece depending upon the strength of the structure of gluten or a starch or a sugar or
28
a fat matrix. The expanding of gases help to create the texture of the crumb which
open up the mass.
d) Conversion of Water to Steam:
The expansion of the dough piece due to formation of steam is much greater
than expansion due to CO2 & ammonia. But CO2 evolves first & then water.
e) Escape Of CO2, Steam, & Other Gases:
The removal of all above falls reduction in overall volume of biscuit. Not all
these are allowed to escape at once time to make a texture & cooling.
Physical changes must be encouraged to takes place in order-environment
conditions, temperature & time i.e. optimum for the particular dough makeup and
the desired attributes of biscuits to be produced
CHEMICAL CHANGES
1) Gas Formation:
The reaction of acid + carbonate / carbonate alone can be regulated by:
a) The solubility of the particular acid/carbonate in the moisture of the dough
b) Temperature and the decomposition range of carbonate.
2). Starch Gelatinization :
When starch or water mixture is heated above 130° F the absorption of water
is very much greater and the starch granules will swell to many times their original
29
size. This is irreversible change. Thus the gelatinization of starch probably does play
an important role in producing biscuit structure during baking.
3). Protein Changes :
Protein (gluten) & other proteins from milk or if eggs & proprietary materials
begin to coagulate at temperature from 105 °F- 145 °F upwards. The coagulation of
proteins imparts strength to biscuit structure.
Denaturation of proteins occurs at 165 °F. so, they become less soluble and protein
fibers become less extensible. Vesicle walls of dough pieces achieve none or less
fixed position and dough expansion ceases. Coagulated protein is drier portion,
starch hold moisture i.e. present. Fat gives tenderness and when all combined give
shortness.
4) Caramelization of Sugar:
It takes place around 3000 F accompanied by the formation of melanoidins and is
the reason for degree of brown crust development. It is the result of the combining of
molecules of sugars such as maltose, dextrose & fructose to produce the colored
(brown to black) substances called as caramels.
5) Maillard Reaction:
Maillard reaction is resulting from the interaction of reducing sugar with
proteins and other nitrogenous material, which gives rise to attractive colors, flavors
& aroma. Around 3500 F the Maillard reaction takes place. Around 475-6000 F the
melanoids become black, bitter and insoluble the nauseous taste of burnt dough.
6) Dextrinization of Starch :
30
At temperature slightly higher than 300 °F, the starch is converted to dextrin. If
slight degree of dextrin can be formed on dough piece surface during baking without
undue caramelization then surface shine will be developed.
Bulk Handling of Ingredients:
Water was the first bakery ingredients to be received and handle in bulk. It is still the material received in the greatest quantity by bakery.
The bulk handling of other ingredients -flavor, syrup, sugar, oil etc.Implementation of bulk receiving by bakery is of required of collaboration of suppliers, carries and purchasers that were relatively evolve.
Recommended Storage Condition :
Ingredients Temperature Range Relative Range Flour 68 to 72 60 to 70Sugar 60 to 80 drySalt 60 to 80 dryBaking powder 60 to 80 dry Flavor 40 to 50 sealed
Pneumatic Transfer Principles:
The essential feature of pneumatic handling, insofar as it refers to bakery ingredients is the movement of particles through tube by streams of air. The two general principles are dense phase and dilute phase transfer.
Dense phase pneumatic conveying method involves relatively low air to solid ratio in which plug of granular material are pushed through tubes.
Dilute phase pneumatic conveying methods involve high air-to-solids ratios in which the individual particles are surrounded by air currents.
Dilute phase system can be classified as-Negative pressure or vacuum system
Positive pressure system Combination systems.
31
Flour and Sugar are the principal particulate ingredients handled by bakeries in pneumatic system-
Transfer from blenders to bins.Transfer from to use bins and recirculation between means.Transfer with in line shifting.Delivery to scale with return line.
Automatic Batching System:
Weighing system for flour, sugar and some other ingredients are integral parts of bulk handling system. Ingredients which are not being handled in bulk transfer system can be dump hoppers. Bag unloders, shifters and conveying system will precede the receiving or surge system.Automated miner ingredients scaling, as found in medium and large bakeries.Convent to the scale.Weighing.Subsequent of weighed ingredients.
Automated bakery generally use a central control panel registering and controlling the operation many remote scales.The advantages claimed for automatic batching include -:
Elimination of human errors. More consistent weight. Better sanitation. Less labor. Redaction in loss of coastally ingredients.
Mixers and mixing: Most bakery procedure is specific to the manufacture of baked products. It is unit operation. Mixing has been defined as a process intended to put a plurality of materials, originally existing separately or in a non uniform combination, into such an arrangement that each particle of one material lies as nearly adjacent as possible to a particle of each material. Mixing as applied to dough, encompassing aeration and development as well as other function. Mixing can be accomplished by many different but they all rely on one more of the following action-
Devices using blades, paddles, helical metals ribbons etc to push portion of the mix through other portion.
32
Devices relying on the elevating and drooping of all or a portion of a mixture so that random rebounding of individual particles result in a redistribution of the particles.
Devices creating turbulent movement by injecting currents of gas or liquids in to a no uniform body of material.
There are significant, in many cases, to separating the mixing process in two or more stages in a preliminary steps, all or part of the ingredients can be roughly blended in to dry mix or slurry that is subsequently divided in to back size portion and then subject to intensive action to insure uniformity and facilitate the physical and chemical changes needed to yield finished dough.
Horizontal Dough Mixers:
Many types of mixture can be, and are, used for batch mixing bread dough but all large bakery whole sale bakeries high speed horizontal dough mixture. In Baghwati food Pvt. Ltd. use low speed (14 rpm).
The mixer is nearly always fitted with a two speed motor to permit high and low speed mixing.
Double arm mixer formally called creamers. They now some type used for stiffer dough.
Sheeters :
There are many operations in bakeries that require dough to be reduced in thickness and shaped in to sheet or strip relatively uniform thickness.The machine performing these operations is called dough brakes, sheeting rollers.
Sheeting Rollers:
Sheeting rollers are used to change the dimensions of dough sheets making it thinner, wider and longer they can also be used to laminate dough. Their axles are always parallel. The web of dough is almost always delivered to the gap by a
conveyor belt and the thinned sheet is taken by another belt. Usually, the sheeted dough web falls free a few
33
inches before it contacts the off take belt. Efficiency of shelters performance is related to rollers speed relative dough velocity, diameter of the rollers, surface texture of the roller, width of the gap between them, rheology of formula being preceded and the amount of dusting flour.Sheeting rollers tend to develop the dough by causing a rearrangement of the gluten molecules.
Rotary Molding machine:
The manufacture of crackers and cookies in commercial plants require certain type of equipment. The rotary molding machine is important equipment in bakery industry. A simple rotary molding machine consist of -
hopper feed role Cylindrical Die A knife or Scrapers A Cloth web or apron And rubber covered compression rollers.
This machine may be permanently a fixed to the oven band. The basic principal of these machines is that dough is pressed in to shaped cavity and then removed from that cavity by adhesion to a belt.
Extraction of dough pieces becomes more difficult as the design complexity increases. Cavity depth will vary according to the desired characteristic of the finished. Ovens and Baking:
Ovens are the most conspicuous and characteristic piece of equipments. The oven has an important influence on product quality.
Heat Transfer Mechanism :
Heat may be generate within a mass by radiation, frication, on chemical reaction, the transfer of heat from outside source by -
Convection Conduction Radiation.
34
The types of radiation that are significant in baking are micro wave and infrared radiation. Radiation has two characteristic that make its action different from other means of heat transfer:
It is subject to shadowing or blocking by intervening substances that are opaque to radiation.
It is very responsive to change in absorptive capacity of the dough.Radiant energy comes from the burner flames and all hot metal parts in the oven.
Convection is transfer of heat from one part to another within a volume of gas or liquid by the gross physical mixing.
In the oven chamber, molecules air gases, water vapor, combustion gases, circulate through out the oven, constantly mixing with other gases and transferring heat by conduction when they contact solid surface.
Translocation of liquid water, melted shortening and other liquid can cause a transfer of heat from one region of the dough to another.
Conduction is transmittal of heat from one part to another part of the same body that is in physical contact with it. When banking dough in a band oven, conduction heat to the dough occurs only through the band. The band received its store of energy from heat conductor through the supports on which it rides.
Bands Oven: The baking surface and which turns around two large metal drum ,one at each end of the oven. The baking chamber can be made very long leading to fast transit times and high production rates. The band oven chamber consist of a frame supporting the necessary rollers, guides, burners, and the like, together with insulation on top, sides, and bottom. One chamber is usually manufactured in modular units.The band ovens have 7 parts.
Packing Equipments:Packing machine contain many type equipment-
Type of Machine – Multi Packs
Hopper Counter Patti pusher Leg supporter Guard controller
Leg35
Infeed Chain (1)Luck (2)Tea Luck
Paper Feed Roller Seal Roller (1)Roller 1
(2)Roller 2 Jaw Section (1)Timer
(2)Cutter Conveyor
Packing Material:
The requirement for an ideal packing material for bakery product might include the following-
(1) The material should protect the product from harmful environmental influences. It will give some protection against the absorption of off-odor.
(2) The package should contribute to the dimensional stability of the product.Since most bakeries are very susceptible to crushing, mechanical strength must be present in the container if the product is to survive storage, transportation, unacceptable amount of distortion, breaking etc.
(3) The packing material should be suitable for being formed into finished package easily and quickly by mechanical means, and preferably by readily available equipment.
(4) The package should assist in selling the product.
(5) The film should be relatively low in price. It must have a favorable cost per square inch and the supplier's factory or warehouse must be located so as to make transportation costs acceptable.
Cellulosic Materials:
36
Among the flexible films that have been used for bakery products are cellulosic materials such as white bakery stock paper, waxed paper, cellophane, and glassine, and combinations of these materials with plastic or foil.The chief advantage of the material is its high breathing value .It should be low cost, whiteness and good quality retention characteristic when it is waxed.
Plastic Resin:
Many of the resin approved for food contact purpose are used largely in the form of films. A film intended for packing foods must have the following characteristic -
(1) Good moisture barrier properties,(2) Aroma barrier properties,(3) Light Resistant,(4) Barrier Properties against absorption of off odors,(5) Acceptable coefficient of friction,(6) Good bond strength of coating, thermal strips, and lamination,(7) Absence of blocking,(8) Good rigidity,(9) Good seal ability,(10) Good appearance and feel,(11) Good low temperature durability,(12) Resistant to high temperature and humidity,(13) Toughness and tenacity,(14) Protection of product freshness.
Standard Of (WFP) Biscuit Packing Material:
C.B.BOXLength 402mmWidth 220mmHeight 300mmDimension = Length X Width X Height = 402 X 220 X 300 = 2653200mm
Flutes Height = 2.5mmNo. of flutes in 30cm = 55 Weight G.S.M.Weight of C.B.Box Pieces = 6.9475 694.75 = 7.2499 724.99
37
= 6.9762 697.62 =7.0000 700.00 Average Weight = 7.0437 Avg.G.S.M. =704.37
General Safety Rules:
The general rule of food safety is of the following-
(1) Equipment should not be operated with safety devices by passed or guard removed.
(2) Only qualified personnel should operate a machine.
(3) Service or maintenance procedure should never be performed on machine in motion.
(4) All air and electric power must be off before servicing the machine.
Sanitation:
Sanitation encompasses the concept of cleanliness in preparing, distribution and serving food but the food manufacture it goes far beyond the usual understanding of cleanliness to include the preventing of -
(1) The food contamination by any filthy material or adulterant or not that thing is readily detectable by the consumer.
(2) Early spoilage.
(3) The spreading of food borne disease by microorganism in the product .It is important to recognize at the outset that a finding of actual physical harm to the consumer is not a prerequisite to a determination that food stuff is contaminated.
38
Assignment in Lab
Determination of Moisture Content by Air Oven Method 39
)
Equipment: Air Oven
Procedures: A known weight of the material is weighed accurately in a suitable moisture dish previously dried in an electric air oven and weighed. The dish is placed in an electric air oven maintained at the temperature required for a particular time. The dish is cooled in desiccators and weighed with the lid.
The dish containing the dried material may be preserved for the determination of total ash where required.
Calculations :
Moisture % by mass = 100(M1-M2) (M1-M)
M1=Mass in g of moisture dish with material before drying. M2=Mass in g of moisture dish with the material after drying and. M= Mass in g of empty moisture dish.
Result - Sugar Moisture
Bowel weight without sample =31.6453g Bowel weight with sample =46.6453g Sample weight before drying =15g Sample weight after drying =14.9959g Moisture% =0.027%
Standard of Britannia moisture content of sugar is maximum 0.10%.Result - Wheat Flour Moisture Weight of empty bowel=42.0247g Weight of sample with bowel before drying=52.0247g
Weight of sample=10g
Weight of sample after drying=50.8160g
% of moisture =12.08Standard of Britannia Moisture content of Wheat flour is maximum 14%.
40
Significance: If more moisture content present in wheat flour then early spoilage occur by micro organism.
Determination of Gluten in Wheat Flour
Equipment: Air Oven
Procedure: 25gm of the flour is weighed into a bowl.15ml of water is added to the flour and made into a dough taking care to see that all the martial is taken into the dough. The dough is kept in the bowl filled with water for one hour. The dough is washed by kneading the dough with hand in water and washings are discarded, taking care to see that no gluten is lost while discarding the wash water. The washing is continued till the gluten is free from starch. After washing the wet gluten is placed on a piece of tared and previously weighed grey board. The gluten is spread into a thin layer and cut into small pieces by means of a spatula. Any residue sticking to the spatula is transferred to the grey board. The grey board with wet gluten is weighed. After weighment it is kept in an airven at 130-135oC for 2 hours 100-105oC for 4 hours for drying. After the grey board with dry gluten is cooled in a desiccater and weighed.
Calculations:Wet gluten% = W1- W X 100
25 Dry gluten % on (dry basis) = (W2 -W) X 100 X 100
25 X (100- M)W = Weight of dried grey board. W1 = Weight of grey board and gluten before drying. W2 = Weight of grey board and gluten after drying. M = Moisture % of flour.
Result - Gluten present in wheat flour is = 9.12%Standard in Britannia gluten present in wheat flour is minimum 7.5.
Determination of Alcoholic Acidity in Wheat Flour
41
Reagents: a) Neutral ethyl alcohol - 90 percent by volume.b) Standard sodium hydroxide solution - approximately 0.05 N.c) Phenolphthalein indicator solution - dissolve 0.1 g of phenolphthalein in 100ml of denatured spirit.
Procedures: About 8 to 10 gm of the sample is accurately weighed in to a dried stoppered 250 ml iodine flask (W). Freshly prepared 50 ml of 90% neutralized ethyl alcohol is poured to the sample and allowed to stand over night with occasional shaking. The alcoholic extract is filtered through what man on 1 filter paper lined funnel, which is mounted, on the 250 ml dried conical flask. Reject the first 10ml of the extract and collect the balance quantity in the same flask. 10ml of the alcoholic extract is pipette in to another 250ml dried conical flask. This solution is titrated against standard 0.05 N sodium hydroxide solutions from the 50ml volumetric burette using phenolphthalein indicator. (A)
Calculation:Alcoholic acidity (as H2SO4), percent byWeight= 24.52AN WWhere A= volume in 'ml of standard sodium hydroxide solution used in titration after deducting blank for 10 ml of alcohol.N= normality of standard sodium sodium hydroxide, and W= weight in g of he martial taken for the test.
Significance:In wheat, carbohydrates are degraded in to alcohol. It's degraded by Fungus, Molds. i.e. Quality of flour has comedown.
Result – Weight of empty bowel = 40.5016g Weight of sample with bowl = 50.5016g Weight of sample = 10g
Value put on formula = 24.52 X 0.05 X 0.5 10 =0.0613%
42
Free fatty acids in oils and fats
Principles: The fat is dissolved in an appropriate solvent, after which the solution is titrated with sodium hydroxide solution. The amount of sodium hydroxide solution consumed is a measure of the acidity of oil.
Apparatus:
Conical flasks - 250ml
Reagents:
a) Solvent - Mix equal volume of 90% Alcohol and diethyl ether Neutralize shortly before use with 0.1 N sodium hydroxide using phenolphthalein as indicator.b) Sodium hydroxide - 0.05 N NaOHc) Phenolphthalein Indicator 1% solution in 90% ethanol
Procedures: About 20gm of H.V.O or refined oil is weighed accurately into a 250ml conical flask. 50ml of the solvent is added, swirled well and titrated against 0.05N sodium hydroxide with phenolphthalein as indicator.A blank test is also conducted on 50 ml of the solvent.
Calculations:
(a) For fats and oils free fatty acid % as oleic acid
=V x N x 28.2 W
Weight in g sample = WVolume (in ml) of sodium hydroxide used = VAfter subtraction of blank volume Normality of sodium hydroxide = N
(b) For refined coconut oilFree fatty acid % as Lauric acid = V x N x 20
W
43
Significance:
The free fatty acid content of a fat is essentially a measure of the amount of hydrolysis that has occurred. Since hydrolysis and oxidation are the reactions leading to organo-optically detectable rancidity, the peroxide value and the free fatty acid content considered together give a reasonably good picture of a fats current status and future prospects.
Result:
Weight of conical flask = 116.6983 g Weight of conical flask with sample = 136.6983 gSample weight = 20 gTitration value=1.1ml
Weight of sample = 20gm.
Value put on formula =
=0.077
Estimation of Ash Content
44
Equipment: Muffle Furnace
Principal:
Ash is the residue remaining after the organic matter of a food has been destroyed incineration and it is the most convenient assessment of the total mineral matter in the material.
Procedure:
About 5- 10 gms of the material is weighed (W1) accurately in a tarred weighed (W) silica crucible the silica crucible is place inside a muffle furnace at 550oC +20 oC.
Till the ash is free from any blank carbon particle after completion of ashing the silica crucible is kept inside the desiccators to attain the room temperature after cooling,
the final weightment (W2) is noted. The ash inside the silica crucible is kept for the determination of acid insoluble ash.Calculation :
Total ash (on dry basis), percentage by weight = (W2- W)X100X100 (W1-W)X(100-M)
Where:
W1 = Weight in g of the dish with the material taken for the test.W2 = Weight in g of silica crucible with the ash, W= Weight in g of the empty silica crucible, and M= Moisture % of the sample.
Result:-
Wheat flour (ash)Crucible weight=30.2687Crucible Weight with sample=40.2687After drying weight of sample with crucible =0.077% of Ash=0.77
Significance: 45
Ash is the inorganic food material. It is undesirable in Wheat flour.
Determination of Acid Insoluble Ash
Equipment: Muffle furnace
Reagent: 5N hydrochloric acid.
Procedure:
The ash kept in the silica or platinum dish / crucible is treated with 25ml of 5N hydrochloric acid, covered with a watch glass and heated on a water bath for 10 min. it is cooled and the contents are filtered through a what Mann No. 42 filter paper. The filter paper is with water until the washings are free from acid. The filter paper with the residue
is returned to the disk. It is kept in an electric oven at 135+ 2oC for 3 hours. It is then transferred to the muffle furnace and ignited at 550+ 20o C for 3 hours. The dish is taken out and cooled in a desiccators and the weight is recorded.
Calculation:Acid insoluble = 100(W2-W) X 100Acid % (d.b. ash) (W1-W) X (100-M) Where,W2 = Weight in g of the dish with All ashW1 = Weight in g of the dish with material taken for the test.W = weight in g of empty dish M = Moisture % of the sample.
Result:
Weight of silica dish-28.8674gmWeight of silica dish with sample-32.8674gmWeight of sample-4gm % ofAsh-0.037
Determination of Sulphated Ash 46
Equipment: Muffle Furnace
Reagents: Con-Sulphuric acid sp. gr. 1.84
Procedure: About 3-5 g of the sample is weighted accurately in a silica dish. 1.5ml of con-sulphuric acid is added and the dish is heated gently of a hot place until the material is will carbonized. The heat is an increased until the evolution of sulfuric acid fumes ceases. The carbonized material is incinerated in a muffle furnace 550+ 20 for about 2 hours. The dish is cooled in desiccators and weighted.
Calculation:
Sulphated ash percent by mass =100 X W1 W2
Where,W1 = weight in g of ash W2 = weight in g of sample.
Result- Empty crucible weight=28.7515g Sample with crucible weight=32.7515g Sample weight=4.0g Weight of ash=0.0015g % of ash= 100 X 0.0015 4.0 =0.0375
Purity as Acetone Insoluble in Lecithin
47
Reagent - A R grade Acetone
Procedure- About 2 gm of the lecithin is accurately weight (W1) into a extraction thimble.The open top portion of the thimble is tightly packed with cotton to avoid any spillage during extraction. A pre-dried and weighted (W2) flat bottom 250ml flask is filled with 100-150ml of acetone. The extraction sample thimble is transferred into a 150ml extractor. The top portion of the extractor is connected to water cooling condenser and the bottom portion is connected to acetone filled 250ml flask. The entire arrangement is placed on the boiling water to carry out the extraction for about 8 hours.
After the completion of the extraction, the sample is removed from the extractor and the excess. Solvent is recovered in the extractor. The complete removal of solvent is carried out by placing the 250ml flask on water bath for 2 hours. For the final drying the flask is kept inside the air oven at 100-105oC for 2 hrs. After drying, the flask is removed from the air oven and kept inside the desiccators to attain the room temperature. Final weight of the flat bottom flask is noted asW3.Acetone insoluble matter % = (W3-W2) X 100
W1
Result: Titration value=7.5mlBlank titration value=8mlWeight of sample=1.25Value put on formula, =7.5-8 X0.05 X 56.1 1.25
=15.0348
Significance: Purity judged by this method.
Determination of Benzene Insoluble Matter in Lecithin 48
Reagents: Benzene AR
Procedure:The material is softened by warming it at a temperature not exceeding 60oC and mixed thoroughly.
10 g of the material is weighted into a 250ml Erlenmeyer flask. 100ml of Benzene AR is added and shaken well to dissolve the lecithin. The solution is filtered through.
A previously dried and weighed filter paper in a funnel. The filter is washed with two successive 25ml portions of benzene. The funnel and filter paper is dried at 100-105 0c for an hour, cooled in desiccators and weighted.
Calculation :
% Benzene insoluble matter =W2-W1 x 100 WWhere;W=Weight of the sample taken for testW2=Weight of filter later with residue left behind.W1=Weight of filter paper.
Result-
Weight of sample= 10.5909gWeight of filter paper=2.2156Weight of filter with residue left behind=1.802gValue put on formula =1.802 X 100 10.5909 =17.01 Significance:
If more benzene insoluble matter present i.e. more impurity.
Sodium Meta Bi Sulphite (SMBS)49
Reagents:
N Iodine solution 0.1 N Sodium Thio Sulphate solution Starch Indicator Conc. HCl
Procedure: About 1gm of the sample is weighed accurately into a 250 ml volumetric standard flask and the sample in dissolved completely by constant swirling. Finally the test solution is made up to 250 ml with distilled water.
25 ml of the test solution is pipette into 250ml Iodine flasks. To that test solution 50 ml of 0.1N Iodine solution is added. In another 250ml dry Iodine flask 50ml of 1.0 N Iodine is added as a blank solution .To both sample and blank solution 10-15 ml of concentrated hydrochloric acid is added and fitted with air tight stopper for one to two minutes.
The solution is titrated against 0.1 N sodium thiosulphate from 50 ml volumetric burette using starch as an indicator. The end point is the disappearance of the blue color.
Calculation:
The purity percentage of Sodium met bi sulhite = V1X47.53X N1
W
V1 - Volume of the thiphosphate N1 - Strength of the thiosulphate solutionW - Weight of the sample
Significance:It is used as a dough conditioner
Determination of Fats50
1. Apparatus: Sox let Extraction Apparatus2. Solvent: Ethyl Ether or petroleum ether distilling below 650 c
Procedure: Transfer about 3 g of the material accurately weighed to a suitable thimble and extract with the solvent in the Soxhlet extraction apparatus for about 0.6 hours. Dry the extract contained in the soxhlet flasks whose empty weight has been previously determined at 950 to 1000C for 30 minutes.Cool in a desiccators and weigh. Continue the alternate drying and weighing at 30 minutes intervals until the lose in weight between two successive weighing is not more than one milligram. Record the lowest weight. Preserve the fat free material for the determination of crude fiber.
Calculation: Fat percentage by weight = 100(W1-W2)
WWhereW1=Weight in g of the sox let flasks, Clean and dryW2=Weight in g of the empty Soxhlet Flask, Clean and dry W=Weight in g of material taken for the test
Significance:In milling time removal of bran and germ is necessary but complete removal is not possible in practical way. Bran and germ contain fat both are undesirable. If more fat is present in wheat flour i.e. early rancidity occurs.
Estimation of Peroxide Value51
Principal:
The peroxide value is determined by subjecting potassium iodide at room temperature to the oxidant effect of peroxides. The Iodine thus liberated is titrated with sodium thiosulphate.
Apparatus:Conical Flasks 250ml with ground -glass stoppers.
Reagentsa) Solvent = Mix 2 volumes of glacial acetic acid and 1 volume of Chloroform.b) Potassium Iodide=Saturated solution Dissolve 4 parts of pure potassium Iodide in 3 parts distilled water keep the solution in a brown bottle.
c) Sodium Thiosulphate= 0.002n Solution prepare this daily from an accurately standardized 0.1 N solutiond) Starch Indicator = 1% solution freshly prepared
Procedure: About 2 to 3 gms of the sample is accurately weighed in to a dried 250 ml Iodine flask To that 25 ml of the solvent is added and mixed homogeneously 1 ml of the potassium Iodide solution is added and allowed to stand in the dark foe one minute After one minute 1 ml of starch indicator is added and the solution is diluted with 35ml of distilled water and titrated against 0.002N solution of sodium thiosulphate from 10 ml volumetric burette. The end point is the disappearance of blue color with 25 ml of chloroform acetic acid mixture is carried out.
CalculationWeight (in g) of sample taken = WVolume (in ml) sodium thiosulphate Used in test = V1
Volume (in ml) sodium thiosulphate Used in blank = V2
Normality of Sodium Thiosulphate = NPeroxide Value = 1000 (V1-V2) N
W
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Result: below 20 to the nearest 0.1 and above 20 to the nearest 0.5.
Significances:
Peroxide value is expressed as milli-equivalentfs (mEq) of oxygen per kilogram of fat. It is an indication of the extent to which the fat has already reacted with oxygen and thus indicates approximately how much storage life remains. The deodorization process applied to fats and oils reduces their per oxide value to zero. Consequently the storage conditions and history of the fat much be taken in to account when determining and using peroxide values to estimate the remaining shelf-life of a fat.
Result:
Weight of sample=2gNormality of Sod Thiosulphate= 0.02Volume Sodium Thiosuphate used in test= 0.13Value put on formula =1000 X0.13 X0.02 2 =1.3
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Kries Test
Reagents:
0.1 % Solution of phiroglucinol in diethyl etherConc. Hydrochloric acid
ProcedureTo 2 ml molten fat sample in a test - tube equal volume of conc-Hydochloric acid is added and shaken well To this mixture a few drops of phloroglucinol solution is added and the mixture is allowed to stand for 2mts.
Result:Development of red (Pink) color in the aqueousgumes layer (acid) is an indication of fat rancidity.
Presence of TBHQ in Oils & Fat
Reagents:MethanolDim ethylamine 40%N-Butyl Alcohol
ProcedureTake 5g of sample in a test tube and add equal quantity of Methanol shake well for 5 mts. To the methanol layer add 5 ml of dimethylamine and n-Butyl Alcohol Appearances of red color confirms the presences of TBHQ.
Significance :
It is used as an antioxidant i.e. prevents oxidant.Example: - Vit-E, Phenol, Lecithin.
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Determination of Melting Point of Solid Substances
Apparatus:Melting point tubesHot plateThermometer -0.10C accurately
Procedure: 7 to 8 cm long capillary tube is fused at one be heating in flame The test sample is filled up to 1 cm in the capillary tube. The capillary is tied to a thermometer using a rubber band .The thermometer is then fixed inside water maintained 100C below the melting point of the sample. The temp of water is slowly resisted at the rate of 0.10C per minute; the temp at which the complete melting of the sample takes place is the melting point of the material.
Significance:
The most important physical characteristic of fat is their consistency under different temperature condition.Result-
Melting point of Palm oil measured is40 0C
Granularity in Wheat Flour
Apparatus: 180 Micron is sieve.
Procedure About 10 gms of wheat flour is transferred to a 180 Micron is sieved and sieved For 2 minutes. The upper surface of the sieve is brushed and sieved again for 1Minute the left over residue is weighed
Calculations W1X100
W1- Weight of the sample for analysis W2 - Weight of the sample retained on test sieve
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Result-Weight of empty bowel=40.4371gWeight of sample with bowel=65.4371gAfter sieving sample weight =0.0180% of sample = 0.018 X 100 25 = 0.072gSignificance :
If Granule size is bigger the proper gluten development and starch setting effected.
Determination of Sedimentation Value in Wheat Flour
Reagents: Lactic acid Isopropyl alcohol Bromophenol blue indicator Preparation of reagent (a)Lactic acid stock solution 125 ml of lactic acid is diluted to 500 ml .This solution is refluxed for 6 hrs. This solutions is marked as Lactic acid stock solution
(b)Lactic acid -isopropyl alcohol mixture 90 ml of the lactic acid stock solution and 180 ml of Isopropyl alcohol are taken in a 500 ml stander flask and made up to 500 ml with distilled water
(c)Bromophenol blue solution
10 ml of bromophenol blue indicator is added to 1000 ml of distilled.
Procedure Mixing
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Place 3.20 g of the wheat flour to be tested in a 100 ml glass stopper graduate cylinder (175 to 180 mm for 0 to 100 graduations) Simultaneosly start the stop watch and ad 50ml of distilled water containing bromophenol blue. Mix thoroughly the flour and water by moving the stoppered cylinder horizontally lengthwise. After 5 mts add 25 ml. of lactic acid & Isopropyl alcohol mixture and continue the procedure for 5 mts. after 5 mts. Result-
Weight of paper =0.3562 gWeight of sample with paper = 3.5562 gWeight of sample = 3.2g Sedimentation value = 19.5
Significance: It describes physical characteristic of wheat flour.
Testing of Corrugated Paper/Corrugated board
Principal
The number of flutes linear foot width of flutes etc. is to be checked by actually measurement.
Equipment
A steel scale with accuracy up to 1/6
Procedure The number of flutes (corrugations) per a linear foot are measured by the scale and reported as such. Similarly, the height and width also are measured.
The corrugated paper or board also has to be checked for flattened corrugation board at the edges of flats distorted corrugation due to indiscriminate use of glue.
Result: WFP (75G) Length of CB-Box =395mm
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Width of CB- Box =220mm Height of CB-Box =292mm Flutes height=2.5mm Number of flutes in 30-55
Measure the weight of 10 cm 2 CB Box peace before drying = 6.9475
=7.1299 = 6.9762 =7.000 = 28.0536gm
Measure the weight of 10cm2 CB-Box peace after drying =6.1376 =6.1626 =6.0874 =6.1377 = 24.5253gm
Result-
Tiger 44g laminate- Cut of length=121mm Width =201mm
Tiger=66g laminates- Cut of length=143mm Width =202mm
The weights of 10cm 2 laminate G S Mare following-
=0.2960g =29.60 =0.3153g =31.53 =0.3132g =31.32 =0.3185g =31.85 =0.2978g =29.78 =0.3149g =31.49 =0.3142g =31.42 =0.3179g =31.79
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=0.3170g =31.70 =0.3136g =31.36 =0.3191g =31.91 =0.3121g =31.21g =374.91/12 =31.2425g Result -
G. S. M of laminate (Tiger-44g) = 31.2425
Determination of Acid Insoluble Ash
Equipment: Muffle furnace
Reagent: 5N hydrochloric acid.
Procedure:
The ash kept in the silica or platinum dish / crucible is treated with 25ml of 5N hydrochloric acid, covered with a watch glass and heated on a water bath for 10 min. it is cooled and the contents are filtered through a what Mann No. 42 filter paper. The filter paper is with water until the washings are free from acid. The filter paper with the residue
is returned to the disk. It is kept in an electric oven at 135+ 2oC for 3 hours. It is then transferred to the muffle furnace and ignited at 550+ 20o C for 3 hours. The dish is taken out and cooled in a desiccators and the weight is recorded.
Calculation:Acid insoluble = 100(W2-W) X 100Acid % (d.b. ash) (W1-W) X (100-M) Where,W2 = Weight in g of the dish with All ashW1 = Weight in g of the dish with material taken for the test.W = weight in g of empty dish M = Moisture % of the sample.
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Result:
Weight of silica dish-28.8674gmWeight of silica dish with sample-32.8674gmWeight of sample-4gm % ofAsh-0.037
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