Biscuit manufacturing process & Quality control.

STRUCTURE OF PRESENTATION
➢Background
➢Biscuit Manufacturing process
➢Various Raw materials used and their role
➢Quality control Parameters of RM, PM & Finished Product
➢Equipment Layout
➢Manpower requirement
➢Trials conducted
➢Observations & suggestions
➢Doubts.

BACKGROUND
Biscuit Manufacturing Company.
The installed capacity of the factory is around 1400 metric tons @ the rate of 56 tons Per day. Till
date highest production of the day achieved has been 61.96 tons.

BISCUIT MANUFACTURING PROCESS
START
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Desired flow
Recyclable flow
Undesirable flow
STACKING IN FG
WAREHOUSE
TO DEHUMIDFIER
ROOM
PROCESS FLOW
RM IN RM
WAREHOUSE
SIEVING &
WEIGHING
STOP
WRAPPING
PACKING IN HM
BAGS
PACKING IN CFC
WEIGHING OF CFC
RAW MATERIALS IN PREMIX AREA
COOLING STACKING
NON RECYCLABLE
(disposed off after
grinding)
MOULDING
LICETHIN
PREPARATION
TBHQ BLEND
SIEVING OF
RM ( minors)
INVERT SYRUP
PREPARATION
BISCUIT
GRINDING
WEIGHMENT
OF MINORS
DOSING OF RM IN MIXER
MIXER
CREAMING 1, CREAMING 2, MIXING
DOUGH IN
TROLLEY
BAKING
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METAL DETECTOR
BISCUITS FALLING ON FLOOR

RAW MATERIALS AND THEIR ROLE
STAGE1 ( 1st Creaming)
Color & Flavor – 0.6875 kgs
Sugar - 84 Kgs
HVO – 44 kgs
SMP – 3 Kgs
TBHQ blend – 1.125 kgs
Licethin Blend – 4 kgs
Liquid Glucose – 2 kgs
Invert Syrup – 18 kgs
Biscuit broken dust – 20 kgs
STAGE 2 ( 2nd Creaming )
Water – 35 to 40 kgs
Ammonia bi carbonate – 3 kgs
Salt – 2.5 kgs
Sodium bi carbonate – 1.5 kgs
STAGE 3rd ( Mixing)
Maida – 250 kgs
DCP – 0.875 kgs
Vitamin mix – 0.425 kgs
SAPP – 0.700 kgs
SMBS – 0.100 kgs
•SMP to be added after HVO for proper mixing to avoid
Lump formation.
Ammonium bi carbonate to be mixed with water before
Adding.
Salt & sodium bi carbonate to added in water before adding
All minor except SMBS to be mixed with Maida before
Dosing into mixer

Variety Ingredients Step SequenceMethod of dispensing
Old Dough Creming-1 1 ****
Color and Flavor BlendCreming-1 2 Blend of both flavor and co
Sugar Creming-1 3 ****
HVO Creming-1 4 ****
SMP Creming-1 5 ****
Broken Creming-1 6 Dry
Lecithin fat+TBHQ fat Creming-1 7 Both blends simultaneou
Invert Syrup + Liq. GlucoseCreming-1 8 Both simultaneously
Salt + S-1 Creaming-2 1 Mixed with water
ABC Creaming-2 2 Mixed with water
S-2 Mixing 1 Mixed with Maida
DCP Mixing 2 Mixed with Maida
NP Mixing 3 Mixed with Maida
Maida Mixing 4 ****
SB Mixing Last dissolved in 0.5 ltr wate
METHOD OF DISPENCING INGREDIENTS FOR GLUCOSE
Glucose

MAIDA
Maida is the main ingredient in biscuits.
Strongly contributes to
• Baked texture
• Hardness
• Shape of the biscuit.
Maida quality has a large effect on the final product as the
proteins in it form a sticky rubbery mass when hydrated and
kneaded known as GLUTEN. This gluten permits the retention
of gas bubbles during baking of the dough to give open textured
& pleasant eating products.

Proteins in Maida
GLUTEN
GLUTEN
A three dimensional structure that imparts extensibility and cohesiveness to the dough
Indicator of the strength of the dough
High Gluten will lead to hard dough ( Strong, difficult to stretch, Elastic.)
Low gluten will lead to soft dough ( Easier to Stretch, extensible & less elastic)
GLUTEN CONTENT TYPE OF BISCUIT
7.5 – 8.5 %
8.0 – 10 %
> 10 %
Glucose / Shells of cream
Marie
Salted biscuits & Crackers
20 %
water soluble
80 %
water insoluble
Albumen Globulin
Glutenin Gliadin

Glutenin Gliadin
GLUTEN
( Extensibility, Strength,
firmness, desirable baking
characteristics to dough)
Cohesiveness, Elasticity
to the dough

Endosperm
Bran
Germ
Wheat Grain
Wheat grain consists of an outer layer Bran, an Endosperm
And a germ.
Maida – Endosperm.
Endosperm – 85.5 % of the grain
Bran – 12% ( weakens the gluten)
Germ – 2.5 % ( Leads to rancidity )
Wheat
Winter
wheat
Spring
wheat
Soft wheat
Flour is fluffy
Less damaged starch
Low water absorption
Protein Levels low ( 8 – 10 %)
Gluten less resistant to deformation
More extensible before getting broken
Dough less rubbery
IDEAL FOR BISCUIT MAKING

SUGAR
• Sweetness
• Structure modifying ingredient
• Flavor modifying ingredient.
Dough
Yeast for Fermentation
SUCROSE
Enhances the rate of fermentation
Dissolves
Re crystallizes after baking thereby strongly
affecting the texture of the baked biscuit
Higher the sucrose level , harder will be the biscuit

SUGAR
SUGAR
DOUGH
• Contributes to the liquid phase
In the dough till saturation level
Reached. Depresses the amount the
Of water needed for dough
• Sugar excess of the saturation level
acts as a bulking agent.
Allows the dough for more time to rise during baking
As starch gelatinisation point is shifted to a higher temp.
ATTRIBUTES
- Acts as an antioxidant
- Caramelizes to affect
the flavor & coloring property

HVO
Fat affects the textural property of final biscuit
Fat crystal
Air bubble
Protein Membrane
• Fat competes for flour space with the aqueous phase to avoid excessive gluten formation ( shortening)
• Gives a soft bite more inclined to melt in the mouth.
• Adds to flavour
• Reduces water requirement for dough making
Higher fat content – short dough Biscuits
Lower fat content – hard dough biscuits

CH COOR
2 1
CH COOR + 3 H2O
2
CH COOR
2 3
Splitting
3 R COOH +
CH OH
2
CH OH
CH OH
2
Triglycerides
Fatty Acids
Glycerol

OILS
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2
Hydro peroxides
Compounds of Pungent &
Unpleasant flavors
H O
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Free Fatty acids
Unpleasant flavors
SaponificationBreakdown
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RANCIDITY

SMP
MILK
Extraction of fat for cream or butter
SKIMMED MILK
LACTOSE PROTEINS
Lactose combines with proteins during Mailards Reaction at the biscuit surface during baking to give
Attractive brown hues
Lactose is 16% as sweet as sucrose and adds to subtle flavor
CAUTION : SMP should be well dispersed in the dough or else small lumps will appear as dark brown or
Black specs in the baked biscuits.

TBHQ
PFA permits TBHQ – Tertiary Butyl Hydro Quinone
But it is carcinogenic hence strict PFA limits are specified ( 200 ppm).
TBHQ is an anti oxidant which retards the oxidative rancidity in fats. It is used for:
- Extending the storage life of fats
- Extending the shelf life of the biscuit.
By preventing the formation of free radicals that initiate and propagate auto oxidation
TBHQ is fat soluble
Ineffective in preventing hydrolytic rancidity.

LICETHIN
Our objective is to get a homogenous dough composition.
Hence good mixture of fats and water necessary
Emulsifiers have a hydrophobic and a hydrophilic part. Hence they
are attracted to both water(liquid) and fat(lipid phase)
They basically reduce the surface tension b/w fat and water – also
called surfactants.
It is used as an Emulsifier
Function of a Surfactant
CMC

LICETHIN
Aids dispersion of fat in the dough and enhances smoothness of the dough
Reduces fat content in the dough by about 10 %.
If used in excess, imparts unpleasant flavors. ( 0.5 to 1 % weight of Maida or 2% weight of fat)

LIQUID GLUCOSE
STARCH
Acid hydrolysis
Enzymatic
Processes
GLUCOSE
( Dextorse, reducing
sugar)
GLUCOSE provide reducing sugars to enhance surface coloration by Millards reaction.
Gives crisp texture without significant sweetness.
Gives a cool sensation on tongue when it dissolves.

INVERT SYRUP
SUCROSE ( Disaccharide)
Hydrolysis
Dextrose Fructose
( Reducing Sugars )
Reducing sugars undergo the Maillard reaction during baking
Reducing sugars + amino acids(from proteins) → Aldoses + ketoses
This imparts dark & attractive surface color(golden-brown).
Fructose gives much sweeter eating sensation than sucrose
Fructose & Dextrose give a cooling sensation as they dissolve in mouth
Convenient way of introducing reducing sugars into formulation to enhance Millard’s reaction during
Baking.
Prevent baked textures from being to hard & brittle
( Acidic Medium )

LEAVENING AGENTS
They are a group of inorganic salts. They produce gases which form the nuclei for textural
development as these gases escapes from the dough during baking process causing the
biscuit to puff.
These chemicals leave residues in the dough which affect the final PH and also flavor.
The common puffing agents used are
Soda(Sodium bicarbonate) and
ABC(Ammonium bicarbonate)

SODA
In presence of water, soda reacts with any acid present to liberate carbon dioxide and the
appropriate sodium salt and water.
Water(in the form of water vapor) and CO2 escape in the oven. This causes the puffing of
biscuit.
Since the sodium salt is a residue, Soda alters the pH of a biscuit. An excess of soda will
give an alkaline taste to the biscuit

The acidic medium for soda is provided by a salt which produces acid.
SAPP, Na2 H2P2O7(Sodium acid pyrophosphate) is added due to its ‘slow’ action.
‘Slow’ action – Our objective is that the leavening agent must emit gases (CO2) when the
biscuit is getting its shape(i.e in the oven)
If some other acid salt (like ACP) added then a lot of CO2 will escape even before baking
process. Hence SAPP preferred.
SAPP

ABC
Ammonium Bi-Carbonate is another very useful leavening agent.
It does not require any acidic medium.
Advantage of ABC : It completely dissociates into ammonia, water and Carbon-dioxide. Hence it
leaves no residue. It causes good puffing and does not alter pH of the final product.
Unique feature of ABC – It does not alter final pH. Hence its quantity can be varied to a certain
extent in the product.

FUNCTIONING OF TWO LEAVENING AGENTS
They operate at different temperature ranges. Hence in the oven, first ABC dissociates and the
biscuit is puffed – ABC acts at around 65 – 70 degrees C
After this Soda starts acting. And maintains the puffed biscuit until the final stage of the oven
where the biscuit structure is finalized
If soda is not added then the biscuit will collapse.

SALT
Salt is used for its flavor and flavor enhancing properties.
Salt toughens the Gluten and gives a less sticky dough.

SMBS
This is a dough-conditioner.
The dough has some sulphide ring bonds. SMBS breaks those bonds and forms linear chains. This
gives a smooth textural finish to the dough.
But due to sulphur again – strict PFA regulations

COLORS & FLAVORS
Colors are added for aesthetic appeal of the product.
Flavors are added for tasting & smelling sensations.

QUALITY CONTROL PARAMETERS
MAIDA
Appearance : White – creamy white. On sieving – free from rodents, weevils etc
Taste and smell : Free from any musty flavor / odor
Particle size : 100% thru 180 micron
PHYSICAL TESTS
On sieving – free from rodents, weevils etc

MAIDA
Moisture : Weigh 10 grams of the sample . Put in the oven at 130 deg. C for 90 minutes. Moisture
Should not be more than 14 %.
Ash: Take 5 gms of the sample. Burn it for about 40 minutes. Keep it in muffle furnace for 4 hours
At 600 deg. C. Should not be more than 0.65 %
Alcoholic acidity: Take 5 gms sample. Add 50 ml of 90% ethyl alcohol. Keep for 24 hours. Filter.
Take 10 ml from the filtered liquid and titrate against 0.05 N NaOH solution. Alcoholic acidity should
Be less than 0.1 %
Gluten: Take 25 gms of sample. Add distilled water 14 ml and knead. Keep in water for half an hour to
Wash off the starch. Dry in oven for 1 hour. Take weight . Should be less than 10 % . Rejected above
12%.
WAP: Should not be less than 55 %.
Sedimentation Value: Take 3.2 gms of sample. Add 50 ml bhromophenol indicator. Shake well for 5
Minutes in the shaker. Add 25 ml Isopropane lactic acid. Shake for 5 minutes. Rest for 5 minutes and
Take reading. Should not be less than 22 ml / sec.
Acid Insoluble Ash: To the ash formed. Add 25 ml 5N HCl. Heat on hot plate for 10 min. Filter on ash
Less filter paper. Wash crucible with distilled water & filter it to remove traces of HCl. Keep the
crucible with filter paper in oven to dry. Keep in muffle for 1 hour. Weigh. Should not be more than
0.05 %.
CHEMICAL TESTS

MAIDA
Moisture :
Ash:
Alcoholic acidity:
Gluten:
WAP:
Sedimentation Value:
Acid Insoluble Ash:
If the moisture level is high the protein will be denatured and will not hydrate to form Gluten.
High moisture will lead to mould growth resulting in mustiness. Low shelf life, low yield.
This indicates the total contamination in the Maida. Ash contains Bran & minerals ( from soil).
Higher the bran, weak will be gluten.
Affects the shelf life, taste & odor of the product.
Measures the protein content in Maida. Higher the protein, gluten formed will be strong, difficult
To stretch but very elastic. Lower the protein, gluten formed will be weak, easy to stretch,
Extensible but not very elastic. 7.5-8.5 % – glucose, 8-10 % – Marie, >10% -Salted/crackers
Water absorption capacity. If low will affect the gluten formation as proteins might be denatured.
Determines the leavening effect. Higher the value, more will be the puffing.
Determines metallic and salacious impurities and indigestive material.
SIGNIFICANCE OF TESTS

SUGAR
Appearance/taste and smell
White crystals free from dirt or infestation. No bad odour. No lumps formation
To check if the sugar is infest free and fresh
PHYSICAL TESTS

SUGAR
Moisture : Take 10 gm sample. Keep in the oven for 1 hour at 105 deg.C. Moisture should not be more
than 0.08 %.
Sulfated Ash: Take 10 gm of sample in a crucible. Add 0.5 ml conc.H2SO4( 98 %). Put on the heater &
char it, until smoke completely goes out. Put in the muffle furnace above 600 deg. C for 1
to 2 hours. When gray ash is formed, take out the crucible and add 1 to 2 drops of sulphuric acid until it is
moist. Put it at 800 deg. C for 15 minutes. Take weight. Ash should not be more than 0.03 %.
SulphurDi Oxide: Take 25 gm sample. Dissolve in 25 ml of distilled water. Add 25 ml of 1 N NaoH.
Stand it for 30 minutes. Add 6 N 25 ml H2SO4. Titrate it with 0.0132 N iodine solution using starch
Indicator. 4000 * titre value / 100 – moisture = SO2 in PPM. Should not be more than 70.
WIM: Take 10 gm sugar sample. Dissolve in 100 ml distilled water. Filter through gooch crucible which
is already weighed ( W 1). Dry the gooch crucible after filtration and take weight again ( W2).
WIM = W2 – W1 * 100 / Weight of the sample.Should not be more than 0.1 %.
Sucrose: Take 5 gm of sample.Dissolve it in 50 ml distilled water. Make it up to 100 ml.Take 10 ml out of
this & add 10 ml distilled water & 1.5 ml conc. HCl & keep on water bath for 10 to 15 minutes & make up
this solution to 100 ml again. Take out the solution in burette and titrate against 12.5 ml each Fehling’s A
& Fehling’s B solution using Methylene blue as indicator. End point is reddish brown brick color.
0.95 *( Titre value) / weight of the sample. Should be minimum 99.5%.
CHEMICAL TESTS

SUGAR
Moisture: If the moisture level is high, this will lead to lump formation and problem in grinding
Sulfated Ash: This a bleaching residue. Harmful to health as being carcinogenic.
Sulphur Di Oxide: Harmful to health, carcinogenic.
Sucrose: Indicates the purity of sugar.
Reducing Sugar: Should be less than 0.1 %. If high, it indicates that sugar is already inverted due to
Hydrolysis.

HVO
Moisture: Take 10 gm sample. Keep in oven for 1 hour at 105 deg. C. Maximum moisture should be 0.1 %
Free Fatty Acid: Take 15 to 20 gm sample. Add 50 ml neutralized ( NaOH + Phenolphthalein indicator
Endpoint : colorless to pink ) boiled ethly alcohol ( 95 %). Add 1 ml Phenolpthalein indicator. Titrate
against
The mixture with 0.1 N NaOH under boiling condition.
28.2 * TV * 0.1 N / Weight of the sample. Should be 0.07 % max.
Peroxide Value: Take 5 gm sample. Add 10 ml chloroform and 15 ml acetic acid and 1 ml saturated
potassium Iodide solution. Titrate against 0.002N Sodium thiosulphate using starch indicator. End point
voilet to colourless. 1000*0.002*TV ( S - B) / Weight of the sample. Should be 1.5 max.
Iodine Value: Take 0.25 to 0.31 gm sample. To this add 25 ml wij solution and 25 ml CCl4. Keep it in a
dark place for half an hour. Add 15 ml 10 % KI solution. Titrate against 0.1 N sodium thiosulphate solution
using starch indicator. End point is brown to colorless.12.09 * 0.1*TV ( S -B) / Weight of the sample.
Should be between 69 to 79.
SAP Value: Take 1.5 gm sample. Add 25 ml alcoholic KOH ( 4 gm KOH in 100 ml C2H5OH). Reflux for
30 min. Titrate against 0.5 N HCl using Phenolphthalein indicator. End point pink to colorless .
56.1 * 0.5 * TV ( B - S)/ Weight of the sample. Should be in the range of 184 to 198.

HVO SIGNIFICANCE OF TESTS
Moisture : High moisture content leads to rancidity.
Free Fatty Acid: This denotes the occurrence of hydrolysis of oil which is then prone to rancidity.
Peroxide Value: This is indicative of oxidative rancidity of the oil
IV: Degree of unsaturation in the oil and hence the shelf life
SAP Value: Denotes the FFA in the oil that have been saponified and hence the rancid tendency..

FINISHED PRODUCT
Moisture : Take 2.5 gm of sample and take the reading from the mettler moisture analyzer. Should be less
Than 1.8 %
Extracted Fat: Take 20 gm sample in a thimble. Take on flask and dry it in oven and cool in a decicator.
Weigh the flask. Take 250 to 300 ml petroleum ether in the flask and attach it to sox let apparatus. Keep
The thimble in the extraction flask. Run sox let apparatus for 2 to 3 hours until all fat is extracted. Dry the
Oven to remove the petroleum ether. Take weight of the flask. Extracted fat should be minimum 12.2%
Acidity of Extracted Fat: Add 50 ml neutralized alcohol to the to the extracted fat. Put the sample in the
Flask and titrate against 0.05 N NaOH. TV *1.41 / Weight of the sample Should be less than 1.2 %
Ash: Take 20 gm of sample. Burn it for about 40 minutes. Keep it in muffle furnace for 4 hours
At 600 deg. C. Should not be more than 1.6 %
Acid insoluble ash: To the ash formed. Add 25 ml 5N HCl. Heat on hot plate for 10 min. Filter on ash
Less filter paper. Wash crucible with distilled water & filter it to remove traces of HCl. Keep the crucible
with filter paper in oven to dry. Keep in muffle for 1 hour. Weigh. Should not be more than
0.05 %.

FINISHED PRODUCT
Moisture : Shelf life.
Extracted Fat: Integrity of formulation
Acidity of Extracted Fat:
Ash: This indicates the total contamination.
Acid insoluble ash: Determines metallic and salacious impurities and indigestive material.

PREPARATION OF TBHQ BLEND
TBHQ : FAT ratio is 1: 120
60 kgs of fat is weighed. Out of this 10 kgs is taken and heated up to 125 deg. C
500 gms of TBHQ powder is added to this and stirred. This is then added to remaining fat
At 42 deg. C.
PREPARATION OF LICETHIN BLEND
Licethin : Fat ratio is 1: 8
160 kgs of fat is weighed and heated to 60 deg. C.
20 kgs of Licethin is added and stirred for 10 to 15 minutes.

PREPARATION OF INVERT SYRUP
195 kgs of water is taken and heated up to 80 deg. C.
To this 650 kgs of crystalline sugar is added.
The solution is heated up to 105 deg. C with continuous stirring.
At 105 deg. C 650 gms of citirc acid ( dissolved in 1 liter of water) is added to solution.
Temp of the solution is raised to 120 deg. C for inversion
Temp of the solution is brought down to 100 deg. C and 260 gms of NaOH ( dissolved in 0.5 liter of
Water) is added.
The solution is stirred for 10 to 15 minutes and sample is sent to lab. For testing.
PH – 4.5 to 5
Brix value – 79 to 81.
Inversion – 60 to 70 %.

EQUIPMENT LAYOUT OF LINE 1
Mixer
Feed
Roller
Cutting
Web
V E N
Burners
Metal DetectorStacker Conveyor
TO PACKING MACHINES
Trolley

EQUIPMENT LAYOUT OF PLANT
Mixer
Feed
Roller
V E N
Burners
Metal Detector Stacker Conveyor
TO PACKING MACHINES
Trolley

5mm clearance
NEW ERA SIGMA MIXER

PRIMA RIBBON BLENDER
0.45 mm
Clearance
5 mm Clearance

COMPARATIVE STUDY BETWEEN RIBBON BLENDER & SIGMA
• RIBBON BLENDER PRIMA
1. Capacity : 0.45 tons
2. Motor H.P. 40; RPM 1440
3. MOC : SS
4. Clearance : < 5 mm
5. Cost of equipment : Rs. 13 Lac
6. Throughput capacity under current
conditions ( batch time including batch
draining of 24 minutes) based on 24 hour
working : 26. 88 tons
• SIGMA MIXER NEW ERA
1. Capacity : 0.5 tons
2. Motor H.P. 50; RPM 1440
3. MOC: SS
4. Clearance : < 5 mm
5. Cost of equipment 26 Lac
6. Throughput capacity under current ( batch
time including batch draining of 20
minutes) conditions based on 24 hours
working : 32.184 tons
MIXERS

MIXERS
• Prima mixer is a type of mixer in
which the raw materials are
mixed by the shearing effect.
• This results in mixing of
materials that gives a soft dough
as physical properties of the
mixing material is more or less
maintained. The dough density
will be low compared to sigma
mixer.
• Chances of moisture retention in
finished product is higher
compared to sigma mixer
• New Era mixer is a type of mixer
in which raw materials are mixed
by compressing effect.
• This results in mixing of
materials that gives a hard dough
as physical properties of the
mixing materials is affected due
to vigorous agitation. The dough
density is high compared to
Ribbon blender.
• Chances of moisture retention is
lower compared to ribbon
blender

• Prima mixer can also be used to
make hard dough by extending
the mixing time after compete
addition of raw materials.
• Sigma mixer however are limited
to making of hard dough only
because in order to prepare a soft
dough, incase mixing time is
reduced, there are chances that
the raw materials may not get
adequately mixed.
MIXERS

TRIAL BATCH
Dough moisture 14.87 %
Wet weight 103.9
Dry weight 101.9
Biscuit dimensions : 117 mm, 58.8mm,
38mm
Biscuit moisture 1.33 %
TRIAL BATCH
Dough moisture 14.62 %
Wet weight 104.4
Dry weight 102.7
Biscuit dimensions : 118 mm, 59mm,
38mm
Biscuit moisture 1.54
MIXERS

OPERATIONAL COST
Motor HP : 40
Energy consumption : 30.4 kwh
For the Day : 729.6 kwh
Assuming power tariff @ Rs 4.5 cost
of operation per day Rs. 3283
A potent ional saving of Rs. 2,87,350
per annum based on 350 days
working.
OPERATIONAL COST
Motor HP : 50
Energy consumption : 38 kwh
For the Day : 912 kwh
Assuming power tariff @ Rs 4.5 cost
of operation per day Rs. 4104
MIXERS

FEATURES
Mixer operation is not completely in
auto mode.
PLC is a three port PLC (Single Stage )
Therefore requires manual inputs.
To be checked for a multi port PLC
incorporation for no touch
operation.
FEATURES
Fully automated operation. Manual
input required only for batch
draining. PLC is multistage with 35
ports.
MIXERS

ROTARY SECTION
Important components
1. Knife (position variable)
2. Feed roll (speed and forward/backward
movement)
3. Die (Speed)
4. Rubber roller (Pressure)

Die
Length – 837.5 ( 32 . 97” )
Dia - 10 “
Biscuit cups – 18 rows * 12 per row
MOC – MS shaft.
Gun metal die
Formed inverted design cups of Mozac V

Forcing roll
Length – 33”
Dia - 8.2 “ (accordingly rpm 1.2 times)
MOC – Cast iron with MS shaft
The feed roll adjustment – The feed roll can be moved
forward/backward to adjust the weight of the biscuits
Possible weight adjustment – 105 g to 99.9 g

Knife position
The knife position is also very important in adjustment of
weight.
Moving the knife up / down changes the weight
Possible weight adjustment 104.5 g to 99.8 g

Oven
The oven is the most critical equipment in the line.
The oven has four different zones.
Each zone has a burner at its centre which supplies heat
The biscuit travels through these zones and gets baked

Construction
1. General construction
2. Burners
3. The flu gas route
4. The steam route

The flu gas route
Combustion cell → behind the oven → damper adjustment →
pipe arrangement(top/bottom) → annular headers → centrifugal
fan inlet
Fan suction → close to 25 mm WG in cold condition

Steam route
Steam rises from dough
Suction through side and re circulation after the three
chambers
1. Exhaust
2. Top and
3. Bottom
Perforated sheets at top and bottom

Plant No. 2 Bentone Burners.
This is a double stage burner with two nozzles. One nozzle B is the bigger nozzle with fuel
Burning capacity of 3 GPH and another nozzle S is a small nozzle with fuel burning capacity
Of 2 GPH.
B S
During start up of the burner at the beginning B will fire first and after a lag of say 1 minute S will fire.
Set temp. on the panel is the indicator of B set temp. say 250. After pressing the ^ button set temp. of S
Will be displayed say 247.
After attaining set temp. of 247 S will trip. After attaining 250 B will trip.
When the temp. reduces below 250, B will start. However temp. will continuous to reduce due to oven
loading. Once the temp. is below 247 S will start.
Benefits: Working is in a very narrow band of temperature variation.
NO colour variation.

2,2 ; 2.5,2 ; 2,2.
In zone 2 the bigger nozzle will continue to be in operation ( say in the temp. band 207 - 214)
At the beginning both the nozzles will get fired till the temp. of 214 deg. is reached. After the
Attainment of 214. Both the nozzles will trip. Below 214 again bigger nozzle will start.And
To ramp up the temp. smaller nozzle will start.

The basic function of each of the zones is heating for various
purposes.
Zone Temperature
maintained
Function of the zone
1 220 1) Moisture removal
2 285 1) Puffing by ABC
2) Moisture removal
3 330 1) Soda action
2) Starting of coloring
3) Moisture removal
4 225 1) Millard reaction (color)
2) Moisture removal

After the oven band the formed, almost set (but hot) biscuits
move onto a stripper band from where it goes for cooling on a
cooling conveyor.
The biscuits are also reversed in the process of cooling and this
facilitates sorting of biscuits (both top and bottom)
After cooling the biscuit must reach almost room temperature.
Cooling conveyor

Metal detector
The biscuits after cooling move on to a PU band which passes
through a metal detector – both Fe and non-Fe
Basic funda – current carrying coils continuously produce a
magnetic field. When a conducting material comes in this mag.
Field an induced current is produced which is measured
The metal detector, through a drive card and a capacitor is given
an 18V, 200Khz input.
There are 3 windings – one is primary and the reading of the
other two are passed through a differentiator and amplifier.
The reading is then calibrated for size of metal inclusion to be
detected – 440 mv in this one. 1mm probes for testing.

PACKING
Biscuit packaging has basically three stages
Primary, secondary and tertiary.
Primary – like the pack of marie
Secondary – the polybag (HMHDPE)
Tertiary – CFC

Multipack packing machine
Basically there is an infeed chain which is carrying the biscuits
Biscuits are carried with the help of lugs. Each stack of biscuits
needs two lugs (one fixed and one moving)
The moving(pocket) lug moves on a profile as shown.
The infeed chain is fed from two sides with the help of pushers
– cross pusher and inline pusher (as shown)
There is a decompressor system for holding the biscuits

Order of operation
1) Inline pusher moves back taking biscuits with it
2) Decompressor holds the biscuits
3) Cross pusher pushes the biscuits
4) Pocket lug springs into position
5) Inline starts moving front
6) Decompressor releases the biscuits
7) By the time inline reaches the biscuit. The cross has
moved back
The cycle hence repeats

There is a thy –rod for adjustment of the inline and cross feed
pusher stroke lengths.
The number of biscuits being pushed can be varied by using
the gauge just behind the inline pusher
Held by the two lugs the bis. stack moves forward
In the wrapper unit, the laminate reel is loaded and it passes
through a number of rollers.
It is mainly pulled by the nip rollers and before proceeding to
wrapping the biscuit it is imprinted with date and code of
manufacture using a markem coder

The markem coder has two rollers. One provides the ink.
The other has letters / numerals fitted in grooves. These pick
up the ink from the Ink roller and print it on the white portion
of the pack.
There is a photo-I mark sensor which senses the black spot on
the laminate to identify a complete reel length also called the
repeat length I.e. length of laminate used for one
pack.(calculation funda again). This senses actual movement
hence giving feedback to the nip roller using a servo motor

The laminate finally passes over a roller before finally going
into the former box.
The biscuit stack comes into the former box and it is here
that the laminate covers the biscuits.
The angle that the laminate makes while entering the former
box, with the horizontal, is a very critical parameter.
Wrong setting of this (tan theta) can lead to bad wrapping
and cause problems such as wrinkles etc.

After the laminate has surrounded the bis. Stack the stack is
carried by 4 lugs (1 at either end at either ends) fitted on
a lateral guide chain. The timing of this is important and
is set while machine installation
There are 3 sets of rollers that this arrangement passes
through
Guide rollers - They pull the laminate and guide it
toward the sealing rollers
These can have an adjustment about their axis(which can
be tilted to adjust the seal width)

Then there are two sets of sealing rollers. Each of these sets
has two rotary rollers with heater on the peripheral surface.
Each of the roller is a 300 w heater. The temperature is about
190 – 200 degrees c
After the first set of sealing rollers the semi-sealed unit passes
through two plates known as the long-seal plates
These have a silica tape within which there are copper wires.
The temperatures of these plates are maintained at about 150
degrees c. The heat given can be adjusted (6, 9 or 12 W)
using a step down transformer.

The final sealing happens in the 2’nd set of heater rollers
After this the packet passes through two jaws which do the
end sealing and cutting.
The top and the lower jaw have a knife and a heater.
The jaws rotate and come in contact when the pack length
finishes. Again high synchro is required

In some cases there may be an additional roller called the
gadgeting roller.
This is present before the end sealings by the jaws
This unit removes the air from the packet by pressing the area
between two stacks of biscuits
In addition there is a mechanical scale for length adjustment.
When different repeat lengths have to be tried, the photo-I
mark sensor is switched off and the length is set by moving a
vernier mechanically (but less accuracy)

PLANT-1 PLANT-2 PLANT-1 PLANT-2
HOME MADE BAKERS GENERAL MANAGER
HOME MADE BAKERS SHIFT INCHARGE
PACKING PACKING INCHARGE
PACKING PACKING SUPERVISOR 1 1 1 1
PACKING MACHINE OPERATOR
PACKING MACHINE FOREMAN 1 1 1 1
PACKING WORKERS
MIXING MIXING SUPERVISOR 1 1 1 1
MIXING MIXING OPERATOR 1 2 1 1
MIXING WORKERS
OVEN OVEN OPERATOR 1 2 1 1
OVEN WORKERS
RM STORE STORE INCHARGE
RM STORE ASSISTANT
RM STORE WORKER
PM STORE STORE INCHARGE
PM STORE ASSISTANT
PM STORE WORKER
FG GODOWN INCHARGE
FG GODOWN ASSISTANT
LABORATORY LAB INCHARGE
LABORATORY LAB CHEMIST
LABORATORY PRODUCT INSPECTOR 1 1 1 1
LABORATORY WORKER
HYGIENE HYGIENE INCHARGE
HYGIENE WORKERS
MAIDA SIFTING & SUGAR GRINDING SUPERVISOR
MAIDA SIFTING & SUGAR GRINDING WORKERS
ROTARY SECTION OPERATOR 1 1 1 1
ROTARY SECTION WORKER 5 4 5 4
ELECTRICIAN
MAINTENAINCE FITTER
MAINTENAINCE ASSISTANT
D.G.SET OPERATOR
LOADERS
OFFICE ACCOUNTS/ EXCISE
OFFICE ASSISTANT
OFFICE RECEPTIONIST
OFFICE OFFICE BOY
PEST CONTROL
SECURITY SUPERVISOR
SECURITY GUARDS
SECTION DESIGNATION SHIFT - A SHIFT - B
1 0
1 1
1 1
8 8
9 9
76 76
21 21
1 0
1 0
1 0
1 0
2 0
1 0
1 0
1 0
1 0
2 1
2 1
1 1
12 12
5 5
1 1
1 1
1 1
16 0
1 0
2 1
1 0
1 0
1 0
1 0
1 0
1 1
2 2
TOTAL MAN POWER ( DIRECT AND INDIRECT ) 204 166
MANPOWER

TRIALS CONDUCTED
Comparative study of Mixers
Physical Weighing of the batch after completion of mixing operation
Making of the batch without adding SMBS.
Running of the dough of Mixer no.1 on line 2
Adding all the raw materials in one go on slow creaming
Adding all the raw materials in fast creaming.
Moisture level of the dough , after zone 1, zone 2 , zone 3 & zone 4.

DOUBTS
Sodium bi carbonate reacts with Sodium acid pyro phosphate to give carbon di oxide, water and a
sodium salt. What is that sodium salt ?

SUGGESTIONS
Metal detector after wrapping of the packets before packing in HM bags.
Shredding of waste wrapper and selling off to scrap vendor.
Preparation of SOP’s for operators
Display banners on safety
Fixing of anti static and current resistant mats
Programming of Prima Mixer PLC.
Separate dosing lines for water addition in mixers
Standard weights for checking the calibration of the weighing scales.

VERTICAL LAMINATOR ROLLER DRIVE- LINE 1
C
R
U
S
H
I
N
G
R
O
L
L
E
R
S
F
I
R
S
T
S
H
E
E
T
I
N
G
S
E
C
O
N
D
S
H
E
E
T
I
N
G
2 Feet
12.5 mm
8
mm
3 mm
2 Feet 2 Feet
Motor RPM 1420
GB Motor ratio
1 : 46
N 1 – 20 Teeth
N 2 – 40 Teeth
N 3 – 30 Teeth
N 4 – 46 Teeth
N 5 – 28 Teeth
N 6 – 28 Teeth
N 7 – 16 Teeth
N 8 - 32 Teeth
N 9
- 28 Teeth
N 10 – 28 Teeth
N 11
- 16 Teeth
N 12 – 40 Teeth
N 13 – 28 TeethN 14
- 28 Teeth
Diameter of Crushing rollers 10’’
Diameter of First Sheeting rollers 8’’
Diameter of Second Sheeting rollers 8’’

No. of teeth of drive sprocket N1 – 20
No. of teeth of driven sprocket N2 – 40
RPM of the motor 1420, Gear Box Motor ratio 1:46
RPM of the drive sprocket V1 – 31
RPM of the driven sprocket V2 – 15.5
No. of Teeth of the drive sprocket N3 – 30
No. of teeth of the driven sprocket N4 – 46
RPM of the drive sprocket V 3 – 15.5
RPM of the driven sprocket V4 – 10
Therefore, RPM of second sheeting rollers – 10
Diameter of the rollers – 8’’
Therefore speed of the rollers – 20 feet / minute.
No. of teeth of the drive sprocket N7 – 16
No of teeth of the driven sprocket N8 – 32
No of teeth of drive sprocket N9 – 28
Therefore RPM of the first sheeting rollers – 5
Speed of the rollers – 10 feet / minute
No. of teeth of driven sprocket N 12 – 40
RPM of the drive sprocket V 11 – 5
RPM of the driven sprocket V 12 – 2
No. of teeth of driven sprocket N 14 – 28
RPM of the drive sprocket V 13 – 2
RPM of the driven sprocket V 14 – 2
Therefore RPM of the crushing rollers – 2
Speed of the crushing rollers – 5.24 feet / minute

Lecithin / TBHQ preparation tank
9 KW heater, one in number + 500 watts heater tracer in the jacket.
Transfer line to storage tanks – 500 watts.
Syrup preparation tank 1 – Height – 1mtr., Diameter – 1mtr. 6 KW heaters 4 in number.
Syrup Preparation Tank 2 – Height – 1200 mm , Diameter 1100mm. Heaters 9 KW 2 in no. , 6 KW 2 in no.
GMS preparation Tank – 9 KW heater 1 in no. + 500 watts tracer heater in the jacket. 500 watts in the
Transfer line.
All storage tanks 500 watts in the jacket.

One sheet of SS 304 from the steel factory comes in the dimensions of 2.5 mtrs. By 1.25 mtrs.
Weight of the steel = Length * Breadth * thickness* specific gravity.
Length 2.5 mtrs., Breadth 1.25 mtrs. Thickness 2 mm , Specific gravity 8 ( for SS 304), 7.85 for MS.
So weight of the sheet – 2.5*1.25 * 2 *8 = 50 kgs.

INSULATION
One tank of 10 square meter of surface area have 75mm thick glass wool insulation is said to give heat
Losses at the rate of 60 watts per meter square. So 10 meter square tank will give heat losses to the
Tune of 600 watts. So a tracing heater of 24 meter will be required with a specification of 25 watt per
Meter. This tracing heater will be fixed only within 30 % of the tank height from below.
The purpose of the tracing heater is to maintain the temp. of the tank.. Even if there an increase in the temp,
It is to the tune of 1 to 2 degrees.

Layering of the hard dough biscuit is done to get a good bite. Just like a parantha is prepared and we
layer it, In the similar fashion the layering of the biscuit dough is affects the bite of the biscuit.

Stack length +1 biscuit height + margin + Jaw width.
Stack Length
End Seal 1
End Seal 2
Half biscuit height Half biscuit height
60 degrees
For glucose 100 gms repeat length – 192 mm
Coil width – 218 mm
CALCULATION OF REPEAT LENGHT
CALCULATION OF COIL WIDTH
2 *(L+W) + Seal Width*2

REFRIGRATION
The compressor compresses the gas. When the gas is compressed its temp. rises ( around 70 deg. More than the
ambient temp.). This heat is removed by the fan provided at the back to atmosphere. The compressed gas then passes
through the condenser and gets converted into a liquid of ambient temp. This liquid then goes to an expansion valve
where the pressure reduces and the volume drastically increases and the temp. reduces to – 35 deg.. This then enters
the evaporator, where heat is absorbed when evaporation of this liquid takes place to gaseous form. The feed air from
the return ducts touch the evaporator and gets cooled which is then sucked by the blower and discharged into the
room. From the evaporator the gas will go to collector where the gas is collected and also separated from the liquid if
any. This gas is then again used as feed for the compressor for the next cycle.
In a compressor circuit, the suction line will have low volume and high pressure and in the discharge end there will
be an expansion valve thru which the liquid volume will be increased and pressure will get reduced.

TBHQ content.
TBHQ fat added in the GL recipe- 1.125 kgs.
TBHQ content – 1.125/121 = 0.00929752 kgs = 9.29752 gms.
Total fat being added in the GL recipe – 44 +3.55+1.115 = 48.665 kgs =48665 gms.
TBHQ in PPM in the GL recipe = 9.29752*1000000/48665 = 191 PPM.
TOTAL ALLOWED PPM OF TBHQ IN FAT = 200
Based on the above we can add
48665*200 / 1000000 = 9.733 gms.

WORKING OF BENTONE BURNER
Thermocouple senses the temperature. If the temp. is low then the relay will switch on the panel. This
Will allow the current to flow thru the solenoid valves at the ports of the suction of the fuel pump. With
Current passing in the solenoid valve the magnets with get activated and allow the fuel to flow in the
Inlet pipes and the burner will start.
Start up: Firstly the combustion air fan will start. Along with it the spark in the electrodes start as it is
Interlocked. After 48 seconds the fuel will get pumped in the nozzles when the solenoid valve which
Is at the discharge port of the fuel pump gets activated.
Solenoid Valve: It has a magnetic operation at the suction ports of the fuel pump. When the current
Passes the magnets get activated and lift and allow the fuel from the ports to the inlet pipes. When the
Current flow stops then magnets get de activated and fuel ceases to flow.

Minute bubbles of
gas formed inside
biscuit
Puffing of biscuit
due to increased
vapour pressure,
puffing max as
biscuits leaves
zone 2
Shrinkage in
volume as gas is
evolved and
vapour evaporated
from biscuit as a
result small cracks
are formed in
biscuit
40
30
20
10
50
60
70
80
90
100
110
Melting of Fat
Gluten coagulated,
Starch gelatinized
Softening of gluten
Contraction of
biscuit, surface
colouration
Gas evolution
complete
Zone 1 Zone 2 Zone 3 Zone 4

Lab testing of minors
Machine changeover
Wastages
Equipment drives
Shamsher Ali
M. Tech Food Engineering
+91 9729035031

Biscuit manufacturing process & Quality control.

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