Milk provides excellent medium for the growth of microorganisms, thus it effects keeping quality of the milk and milk products. So, to prevent this cleaning and sanitation of dairy equipment and plant is done to keep the consumer safe.

1. MILK AND MILK PRODUCTS TECHNOLOGY
Topic -Cleaning and Sanitation of Milk Plant
Dr. S.V.D TEJA
M.V.Sc
Livestock Products Technology

2. Introduction:
 Milk provides an excellent medium for the growth of microbs, so the residues from
it can effect the keeping quality of the milk.
 Thus detergents and sanitizers are used for this process.
 Cleaning and sanitation are complimentary process

3. Cleaning – Cleaning or washing of dairy equipment's is removal of soil (milk/ milk
residue/ foreign matter) from the surface of equipment.
Sanitization – It is destruction of all pathogenic and almost all non pathogenic
microorganisms from surface of equipment.
Detergent – Substances used for cleaning a/Kas cleaning/washing compound.
Sanitizer – substances capable for destroying all pathogenic & almost all non –
pathogenic mirobes.

4. Detergent:
 Characters of detergent
1. Wetting & penetrating power
2. Emulsifying power
3. Saponification power
4. Deflocculating power
5. Dissolve very easily
6. Ability to make water soft
7. Germicidal properties
8. Non- corrosive
9. Non- toxic
10. Can be stored for longer period
11. Mild on hands

5. Classification of Detergents
1. Alkali Detergent
• Used to neutralize, break-up, and suspend soil in the cleaning solution.
Alkalines have been termed the "guts" of the dairy cleaners and are usually
termed generically as "caustics" and or alkaline chlorinated cleaners.
• They are generally combined with a water conditioning additive such as
liquid phosphate under hard water conditions and usually contain surfactants or
wetting agents which enhances the cleaning action

6. • Eg- NaOH: used for hand & stainless steel equipment.
Na2CO3: Used for cleaning aluminium and tined copper.
Sesquicarbonate: Aluminium & tined surface.
Sodium meta silicate: used as emulsifier & deflocculating power.
2. Acid Detergent
• Acid based detergents (or rinses) do not saponify.
• They do, however, tend to neutralize any alkalinity and react with the milk
minerals which are then carried away in the rinse cycles. Acid rinses will
usually provide a bacteriostatic condition, however the equipment must be
effectively cleaned with an chlorinated alkaline based detergent prior to using
the acid rinse

7. • Acid detergents are those with a pH of lower than 7 and react with mineral
deposits which have accumulated on milk contact surfaces. These acid cleaners
may contain either nitric, phosphoric or a mixture of both acids
• Strong acid: nitric acid 1%
• Mild acid: phosphoric acid , tartaric acid , gluconic acid are used at 7%
3. Polyphosphates: These are used with above cleaning agents when hard water is
used Eg: Tertameta Phoshpahate, Hexameta Phosphate, tripopolyphospahate.
4. Surface active & Wetting agents: These detergents are having property of
wetting and surface active substances . Eg: Teepol, Idet -10, Lisopol, Picino- N

8. Sanitizer:
 Properties of Sanitizer:
• It should should be non toxic
• Relatively non- corrosive to hand equipment.
• Quick acting, easily applied
• Economical, relatively inexpensive
Examples:
1. CHLORINE: Chlorine is the most common chemical sanitizing agent used in the
milk industry. One of the most common forms of chlorine is sodium hypochlorite which is
the soluble salt of hypochlorous acid combined with sodium chloride. This is the stable
form of a liquid chlorine solution however has a limited shelf life

9. • Chlorine sanitizers are generally used in recirculated cleaning systems for cleaning
small parts, milk tank trucks and environmental surfaces.
• Temperatures of the solution also play an important role in chlorine effectiveness
rates. Optimum temperatures of chlorine range from 75o F - 100o F.
Examples: Chloramines – T, Hypochlorite,
2. IODINE : Iodine sanitizers used in milk plants are usually in the form of
iodophors. Iodophors are simply iodine which are combined with non-ionic wetting
agents.
• Iodine sanitizers are used extensively in filling/packaging machines and areas,
culture processing equipment, drop hoses and hand dipping stations.

10. Examples: Iodine
3. QUATERNARY AMMONIUM COMPOUNDS: (Cationics) These sanitizer agents are
commonly known as "Quats" and are highly effective in the denaturing of cell
(bacteria) proteins which leads to their destruction.
• Quats are generally used in case washing areas and other environmental surfaces,
but are rarely used in CIP and plant equipment sanitization where culture
processes may be damaged.
Examples: Acetyl trimethyl ammonium bromide

11. Principles of Cleaning and Sanitation:
1. Before selection of any detergent or sanitizer consider soil, quality of water supply,
type of metal used for equipment's and most important is the method of cleaning and
sanitizing.
2. Heat : 15 psi/ 5 min or scalding water(90 – 95 °c/10 min)
3. Drainage
4. Pre rinsing with hot or cold tap water
5. Detergent washing with 0.15- 0.60% alkalinity to remove milk solids
6. Hot water rinsing to remove excess detergent
7. Sanitization – To destroy all pathogenic and non- pathogenic microbs
8. Drainage and drying – To prevent bacterial growth and prevent corrosion

12. Method Of Cleaning And Sanitization:
Hand Washing:
• Prepare 0.8 to 1.0% of detergent mixture in tap water so as to give a minimum
alkalinity of 0.5% in a wash up tank and maintain the temperature at about 500C
• Thoroughly rinse the utensils with clean cold water
• Introduce the detergent solution in to the equipment thoroughly brush the
equipment surface, inside and out side with a clean can brush
• Wash the utensils with enough fresh cold water using a clean brush again if
needed to remove all traces of detergents
• Allow the equipment to drain thoroughly and let it dry for at least one or two
hours
• Sanitize the equipment surface by steam or hot water after cleaning and or by
rinsing with chlorine solution (200 ppm available chlorine) just before using

13. Mechanical: This method is used to clean and sanitize can and bottles
1. Can washing:
Draining
Prerinsing with cold water
Draining
Detergent (70°C)
Steam and water at (88°C)
Rinsing with steam (88 to 90°C)
Hot air drying 95 – 115

14. Types of can washer:
ROTARY CAN WASHER STRAIGHT TUNNEL CAN WASHER
Small scale Large scale / big plant
Loading and unloading at the same place Loading at one end & unloading at other
end
Single person operated At least two persons
2-6 can per minute 4-6 can per minute
Can moves in circle Can moves straight

15. 2. Bottle washing:
Pre rinse using water at 32 – 380C
Detergent wash with 1 – 3 % caustic soda at 60 – 750C.
Warm water rinse: To remove all traces of detergents 25 – 450C
Cold water rinse: Containing 35 to 50 ppm available chlorine is used
Draining after the bottles come out of the machine
Types of bottle washing:
a) jet type – Jet spray of water and detergent is used
b) Soaker type – Provided with different pockets of cleaning and sanitizing agents

16. 3. CIP (Clean In Place/ In Place Cleaning)
• This refers to that system of cleaning and sanitization which does not require the
daily dismantling of dairy equipment.
• Steps involved :
1. Pre rinse with cold water
2. Acid rinse with phosphoric acid of 0.15 – 0.60 % at 65 -70°C for 20-30 min
3. Drain out acid solution
4. Hot water rinse at 65 -70°C for 5 to 7 min
5. Alkaline rinse of 0.15 – 0.60 % at 65 -70°C for 20-30 min
6. Drain out the alkaline solution
7. Final hot water rinse at 71 – 82°C

17. Merits
• Eliminates the human factor
• Less damage to equipment
• Time saving
• Reduces the possibility of contamination through human error
• Improved plant utilization and appearance
Types of CIP systems
• Manual control
• Automation
• Low level
• Medium level
• High level