It mostly covers all the theoretical aspects regarding cleaning in dairy industry.

2. Presented by :Tamal Sarkar
MTech, DairyTechnology (NDRI, Karnal)
An overview

3. Process of removing
unwanted soil (fats,
proteins, sugars,
scaling, etc.) from
equipment by
application of an
effective procedure,
either manual or
automated.
Operation where
bacterial count are
taken down to the
microbial safety limit
by mostly by the
application of
chemical or heat.
Process of
destruction of all the
living cell by the
application of heat.
Cleaning Disinfecting Sterilization
National and international legislation requires the food industry to put safe food on the
market (European Commission 2002). Physical, chemical and (micro)biological
cleanliness are prerequisites for food safety.
Sanitizing in broad interpretation is: Cleaning + Disinfecting

4. Hygienic zoning
Basic hygienic
zones
• Require Good
Manufacturing
Practices, no open
product handling in the
area.
• Milk reception,
Incoming material
reception
Medium hygienic
area
• Products are not
sensitive to get
detreated by
conditions.
• Areas outside the
closed equipment's
• Filtered and
conditioned air is
required
High hygienic
zones
• Here the process
products are exposed.
• Highest level of
hygiene is required
here.
• CIP process is a basic
requirement here.
Physical segregation of different unit operations using physical barriers in regards
to hygienic level.

5. Dry cleaning
Process of removing
unwanted soil, using
an effective procedure,
from equipment and/or
manufacturing
facilities, without use
of water (including
aqueous solutions or
steam).
Wet cleaning
Process of removing
unwanted soil, using
an effective
procedure, from
equipment and/or
manufacturing
facilities, with the use
of unrestricted
quantities of water.
Cleaning in Place (CIP)
CIP is a method for
cleaning the
production lines
without dismantling
the installation by
circulating cleaning
solutions according
to defined
protocols,
combining physical,
mechanical and
chemical energies.
Cleaning out of Place
(COP)
COP is a method of
cleaning whereby
equipment or parts
of equipment are
removed from their
normal place of use
in a food
processing
operation
specifically for
purposes of
cleaning
*Marketstandmarkets.com
Types of cleaning :

6. Fouling
Cleaning parameters
Quality aspects
Validation
Innovative Technology

7. Whey
Proteins
Inorganic
salts
Caseins Others
*At 70℃ denaturation of β lactoglobulin starts and around 90 ℃
aggregation takes place
Monolayer of protein abs on surface even at room
temperature.
Process of deposition formation on the equipment surface wall

8. Whey
Proteins
Inorganic
salts
Caseins Others

9. Whey
Proteins
Inorganic
salts
Caseins Others
K casein + β lactoglobulin =
Coagulation
β lct may act as sticking agent of
casein and wall
Colloidal stability is low than casein
may ppt upon heating.

10. Whey
Proteins
Inorganic
salts
Caseins Others
Dissolved air,
Fat, lactose(
>100℃)

11. Types of fouling :
FoulingType A
• The heat exchanger operating at temperatures around 100°C where the deposit is
composed of 50 to 60 % proteins, 30 to 35 % inorganic matter
and 15 to 20 % fat.
• Soft and spongy in texture.
FoulingType B
• In sterilization at around 130-140℃ temperature composition of deposition has around
70% of inorganic minerals
• Hard and brittle in texture.
Types of fouling Type A (%) Type B (%)
protein 50-60 15-20
Minerals ( calcium phosphate ) 30-50 70-80
Fat 4-8 4-8

12. pH [Ca] Air β-LG T DeltaT Re Ageing
- +++ ++ +++ + + -- ++
+++ ++ -- -- - - +
Effect of various parameters :
Reduction of fouling deposit :
➢ Applying steam injection/infusion to shorten the period of heat treatment.
➢ Applying such high shear stresses in the critical region t
➢ Installing a holding section with a high volume to area ratio.
➢ Degassing the milk, applying high operational pressures and high shear rates
➢ Desalting, adding Ca2+ binders and adjusting pH
+ is positive effect
- Is negative effect

13. 4 main parameters :
➢ Mechanical force
➢ Chemical force
➢ Thermal force
➢ Time for the force to act
Mechanical force
Shear forces created by the flow through the nozzle which increases the velocity of
the water and the water jet gets “harder”.
Flow must be turbulent as the flow velocity more than 1.5 m/s.
Sinner’s circle

14. Chemical parameters
Alkaline detergent Acid detergent Disinfectant
Inorganic soils:
milk stone, mineral
scale
Ex : nitric acid ,
phosphoric acid.
It is given at conc.
0.5- 2 %
Organic soils : Fat,
protein, Grease Kills the
microorganism by
complex reaction
outside or inside
the cell.
Heat, Chemical
disinfectant are
used

15. Thermal Force
Type of detergent Temprature
range(℃)
Cleaning objecet
NaOH 60-80℃ Milk collection tankers, tanks, pipes
70-90℃ Milk pasteurizer
90-140℃ UHT tanks
HNO3 60-65℃ Tanks, pipes, milk pasteurizer
80-85℃ UHT plants
Time
It eventually varies with cleaning process and parameters ( Conc. Of detergent,Temperature)

16. Water :
Often known as universal solvent.
Key attributes:
Key attributes Limits
Sensory quality Potable
Microbial standards
1.Total bacteria Less than 100 per mL
2. Coliforms Absent in 100mL
3. E. Coli Absent in 100 mL
pH 6.5-7.5
Sulphides/sulphates 250µg SO4 per lit
Chloride Not more than 250µg/mL
Iron 200µg/mL
Manganese 50µg Mn/L
Classification of water hardness
Soft 0-6 °dH
Medium hard 6 -12 °dH
Hard 12 -18 °dH
Very Hard > 18°dH
1 °dH German degree = 17.9 mg CaCO3/L
Water hardness should be between 4- 7 °dH
crevice corrosion

17. Detergents :
Formulated in 2 types :
➢ Pure chemicals
Pure detergent concentration by
manufacture : NaOH (sodium hydroxide) 25-45 wt%
HNO3 (nitric acid) 52-68 wt%
H3PO4 (phosphoric acid) 75-85 wt%
➢ Formulated Chemicals ( Pure chemicals + additive )
Optimization of concentration:
Lab trials on optimum design of concentration done by Tetra Pak.

18. Inline measurement of concentration
It is performed by measuring electrical conductivity of a solution, depends on composition,
mobility of ion, valance of ion and temperature
Conductivity versus concentration at 25 °C
Kθ = Conductivity at θ ℃
K25= Conductivity at 25 ℃
α =Temperature compensation co efficient
Detergent type Temperature compensation co
efficient
Sodium hydroxide – NaOH 1.7%/°C
Nitric acid – HNO3 1.3%/°C
Phosphoric acid – H3PO4 -0.01*Temperature + 1.17%/°C

19. Additives
Surfactant
• Makes the water insoluble oil deposit soluble in water by decreasing surface tension.
• Incorporation is usually desirable in order to enhance the total qualities of any given formulation.
concentrations of less than 0.1 g or mL 100 g−1 or mL−1 ( Ionic or non ionic molecules)
Inorganic components
• Silicates softens the water by formation of precipitate, It allows suspend the soil in solution, also act as
buffering agent.
• Complex phosphate ion can act as sequestering agent, deflocculating agent ( tetrasodium pyrophosphate)
Sequestrants
• It basically binds the metal ion and prevent the hard water scale on the processing chamber.
• Organic sequestrants like EDTA(stoichiometric) and Inorganic sequestrants amino tri-methylene
phosphonic(Threshold) acid are basically used.

20. Disinfection is reducing microorganism to a level that does not compromise food safety or
suitability and is done with chemical and/or physical methods.
Sterilization is the complete destruction or elimination of all living microorganisms, viable
spores, viruses, and viroid's. Steam under pressure at 125℃ for 30mins.
Factors effect the performance:
➢ Time
➢ Temperature
➢ Concentration
➢ Surface tension
➢ pH
➢ Organic matter
➢ Metal ions

21. Types of disinfectant
Heat
• Steam, Hot water or hot air may be used.
• It is costlier process, requires plant to get cooled, Loosen the elasticity of gaskets.
Chlorine
• It has bactericidal powder, can oxidise the protein in bacterial cell protein leads to the
destruction.
• Typical range of available chlorine used are range of 50 to 250 ppm.
QAC
• Quaternary ammonium compound carries very strong + ve charge makes good contact
with –ve charge surface.
• They are low in toxicity, used in ordinary environmental sanitation.
Iodophors
• It is mixture of elemental iodine and wetting agents. Iodine is known to combine with –
SH group of microbial enzyme and being lethal
• It is typically used 50 ppm.

22. General CIP procedure
Source: Jeurnink & Brinkman

23. Cleaning cycle of different equipment's:
Equipment Pre rinse Alkaline
washing
rinsing Acid
washing
rinsing Sterilizatio
n
No of steps
Evaporators Warm water-
45℃
1-4%
solution,
80℃, 45-
60mins
Warm water 0.3-0.5%,
70℃, 20-30
mins
Warm water 75ppm of
chlorine for
5 mins
7 step
process
UHT system Cold water,
15 mins
1-3%, 90-
105℃, 20-
30mins
Flash water 0.5-1%, 60-
80℃, 20-
30mins
Cold water,
15 mins
5 Step
Heat
exchanger (
Weekly)
Water rinse,
> 10℃, 3-5
mins
1.5% NaOH,
70℃, 20
mins
Warm/ cold
water, 5
mins
1%, 65℃,
10mins
Cold water,
10 min
5 step
process
Milk tanks
and pipes
Water rinse
> 10℃
1.5% NaOH,
60-80℃,
30mins
Warm water
>50℃
0.8%, 60-
65℃,
30mins
Cold water
rinsing
_ 5 step
process
Aseptic
fillers
Warm water
50-70℃
1-1.5%, 15-
20mins
5-10 rinsing 0.6-1.2%,
60-80℃, 15-
20mins(wee
kly)
Cold rinsing
5-10mins
Sterilization
140℃, 2-5
mins
5/7 step
process

24. CIP validation/verification/monitoring
Validation should ensure that the information supporting the cleaning process is correct.
➢ Monitoring of process parameters.
➢ Bioluminescent ATP assay.
➢ Direct microbial count of rinse water
➢ Redox reaction in presence of persulphate or
potassium permanganate(KMnO4)
➢ Visual inspection of open line.

25. Verification determines whether the process agreed after validation performs in the right way.
It is a continuous process, similar to monitoring, but with a lower frequency.
➢ Surface swab test
➢ RODAC – Surface contact plates
contain agar are used.
➢ Direct count of fresh rinse water.(
level given below in the table)
Microbiological criteria for
potable water
Maximum concentration
(colony forming units, cfu)
Total coliforms 0 cfu 100 mL−1
Faecal coliforms 0 cfu 100 mL−1
Faecal enterococci 0 cfu 100 mL−1
Sulphite-reducing clostridia Less than 1 cfu 20mL−1
RodacSwab test
UK water supply regulations

26. Monitoring refers to the regular measurements taken on the cleaning process that serve as
indicators of whether the process is in a state of control.
• ATP – rapid, relatively simple to use;
• microbial swabs;
• visual inspection;
• test strips for residual protein testing (linking to
allergens).
The aim of monitoring is to ensure that cleaning procedures minimize and control the
risks of product and line contamination
Monitoring of fluids :
➢ In line monitoring ( pressure
drop, turbidity, conductivity)
➢ Environment monitoring
Monitoring of equipment’s :
Benefits :
➢ economic cleaning,
➢ early warning of possible product
➢ longer production runs
➢ longer equipment life,

27. Bio detergents
Enzyme based bio detergent are fast emerging as an alternative to synthetic
detergent.
It was discovered by Dr. Otto Rham, patented use of pancreatic enzyme which
removes protein strain
➢ Protease
➢ Lipase
➢ Amylase
➢ Cellulase

28. IntelliCIP monitors the level of soiling present on the internal surfaces of the
equipment being cleaned.
It was developed by tetra pak.
IntelliCIP
Typical distribution of fouling in an indirect UHT plant for white milk

29. Conclusion
Cleaning is an essential step in dairy industry. It ensures safe products and
long lasting life of equipment.
Biofouling is still a difficult to prevent and remove, Feature development will
focus on technology of reducing the deposition and improve cleaning rate.
In this pandemic situation industries are more concerned over improving
overall hygiene, acceptable CIP is a crucial measure .