Condensed milks are the products obtained by evaporating part of the water of whole milk, or fully or partly skimmed milk, with or with without the addition of sugar.

1. Condensed & Evaporated Milk

2. Skimmed milk products are known as sweetened condensed skimmed milk &
unsweetened condensed skimmed milk
Condensed & Evaporated Milk
Condensed milks are the products obtained by evaporating part of the water of whole
milk, or fully or partly skimmed milk, with or with without the addition of sugar.
The term condensed milk is commonly used when referring to full cream sweetened condensed milk
The term evaporated milk is commonly used when referring to full cream unsweetened condensed milk

3. Condensed vs Evaporated Milk
Both condensed milk & evaporated milk
are forms of concentrated milk
in which approximately 60% of the water content
has been removed
The major difference that sets these two canned milk products apart is
sugar content
evaporated milk
always sweetened
Sweetened condensed milk
always unsweetened

4. Types of condensed milk
FAT TMS
UK USA UK USA
Condensed milk 9.0 7.9 31.0 25.9
Evaporated milk 9.0 8.5 31.0 28.0
Skim sweetened - - 20.0 20.0
Skim unsweetened - - 26.0 24.0
Gross composition of condensed milks

5. Physico-chemical Properties of Condensed Milk
a). Specific gravity/density
b). Freezing points
c). Colour and flavor
d). Viscosity
The principal factors affecting browning-discolouration & cooked flavour
production:
i. Heat treatment
ii. Total solids concentration
iii. pH
iv. Storage temp. and time
v. Oxygen content
vi. Various added compounds

6. The viscosity of condensed/evaporated milks seems to be
influenced by the following factors
i. Concentration
ii. Composition
iii.State of protein and fat
iv.pH and salt balance
v. Temp. of forewarming/preheating
Physico-chemical Properties of Condensed Milk

7. Role of milk constituents in Condensed Milks
Imparts a rich in and pleasing flavour, soft body and smooth texture to both
condensed and Evaporated milks. Significant in flavour problems such as
rancidity, tallowiness etc. by affects by viscosity.
Their physico-chemical reactions to processing heat largely determine the heat
stability and viscosity of condensed milk.
a). Milk fat.
b). Milk Protein

8. 8
These salts particularly Ca and Mg together with citrates and phosphates are
control the salt balance and heat stability of milk. A disturbed salt-balance causes
objectionable heat coagulation of milk
Play an important role in the successful control of the texture of condensed milk.
The size of lactose crystals determines the relative smoothness of condensed milk,
and is controlled by the procedure used for the cooling and crystallization of this
products.
c). Milk Sugar
d). Mineral salts
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9. 9
Manufacturing procedure of Condensed Milk

10. 10
Basic principle of Condened Milk
The basic principle in the production of condensed and evaporated milk is
that high quality milk is filtered/clarified, standardized, forewarmed and
condensed/evaporated to the desire level. The concentrated product is
preserved by the addition sugar for condensing milk and by heat sterilization
for evaporated milk.
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11. Manufacturing procedure of Condensed Milk
Flow diagram of manufacture
Receiving milk
Heat treatment/Condensing (2.5:1)
Filtration/Clarification (38-40º C)
Cooling and crystallization
Addition of sugar
Packaging
Homogenization
Forewarming/preheating (115-118 º C / No Hold)
Standardization
Storage (10º C)

12. 1.Receiving milk:
The quality of raw milk always influences the quality of prepared condensed
milk.
The milk should be clean, sweet, free from off flavors & odors and
reasonably free from extraneous materials.
Contaminations by antibiotic, pesticides & other chemicals & metals is
highly undesirable.
Acid development is highly objectionable. No abnormal milk should be accepted.
When the receiving the should be performed COB and alcohol tests.

13. Before doing the operation, the milk is warmed to 35 to 40º C.
Warming helps to decrease the viscosity & the filtration/
clarification becomes easier.
After filtration, milk is cooled so as to preserve its quality.
2. Filtration/ clarification:
This is done in order to remove visible foreign matter

14. The standardization of raw milk is normally carried out in three stages-
(i) The first standardization, which established the desired ratio of fat: SNF (usually 1:244).
(ii) The second, which establishes the desired ratio of added sugar to the total milk solids.
(iii) The third, which adjust the concentration of the finished condensed milk to the desired
percentage of total solids.
3. Standardization:
Done to conform to legal standards in the finished product

15. The temperature-time of fore warming/ pre-heating extents over a wide range, such as
 82 to 93ºC for 5 to 15 minutes
 116 to 149ºC for 0.5 to 5 minutes.
 The modern trend is towards high temperature short time heating 115 to 118ºC
for no hold)
4. Pre-warming/preheating:

16. This steps serves following processes:
1. To ensure the finished product free from microorganisms & enzyme;
2. To ensure uninterrupted boiling in the vacuum pan.
3. To provide an effective means of controlling objectionable age-
thickening in the finished product
4. Pre-warming/preheating:

17.  Generally, sucrose is added for this purpose.
 Highly refined cane, beet sugar may also be added.
 The amount of sugar ranges from 40 to 45% in the finished
produced, which required 18 to 20% on milk basis.
5. Adding sugar:
Purpose: preserving the condensed milk without resorting to sterilization by heat.

18. This operation is carried out in an evaporator, (also known as vacuum pan).
6. Condensing:
Basic principle: Removal of water from the standardized milk by boiling it under
partial vacuum at a low temperature till the desired concentration is reached.
Quality of condensed milk produced by vacuum condensing is always better than
the milk produced by other types of evaporations.

19. A special type of homogenizer suitable for holding a highly viscous product is used
at a total pressure of 2500 psi (2000 psi in the first stage & 500 psi in the second stage).
7. Homogenization:
Purpose: Obtain a uniform fat emulsion & reduce fat
separation to a minimum during storage.

20. To destroy the tendency of age-thiehning & discoloration, that
accelerated by prolonged exposure to heat.
8. Cooling & crystal action:
Smoothness of texture of the finished product & its freedom from
an objectionable sugar deposit also depends on prompt cooling.
Prompt cooling is desirable :
The relative smoothness of condensed milk is controlled by
the number of & size of the lactose crystals it contains.

21. Rapid crystallization leads to the formation of large number of small size crystal (5 to 8
microns), giving a smooth texture to the condensed milk.
About 375 to 500 g fine lactose power/100kg of the original fluid milk or, 0.1 to 0.3%
of condensed milk is sprayer on the milk at a temperature of about 30 to 40ºC.
Vigorous stirring during that time is necessary, otherwise size of crystal will be big.
To produce fine crystal:
This usually takes about an hour.
Temperature should be reduced to 13 to 18ºC with continuous agitation.

22. After crystallization and cooling, condensed milk is ready for packaging.
9. Packaging:
After filling, the cans are sealed, labeled and packed in cartoon for
storage and distribution.
For retail market, small size cans are filled.
Bulk packaging may be done in barrels of various sizes with polythene
liners or aluminum coating.

23. A very low storage temperature such as 0ºC or, below may not only cause sandiness
but also sugar (sucrose) separation.
10. Storage:
Main consideration in the storage of condensed milk: Temperature of
storage, which should be to prevent such defects as sandiness, sugar
separation, & viscosity changes.
During storage, a temperature variation may increase the tendency to sandiness.
Cold storage is important to prevent viscosity change.

24. The trend in recent years has been to store condensed milk at 10ºC or slightly below.
The humidity of the surrounding air should be low (below 50%) to cheek spoilage of
cans & lebels.

26. Homogenization
Cooler
Evaporation
Manufacturing procedure of Condensed Milk
Receiving of raw milk Filtration/ clarification Standardization
Preheating
Intermediate tank
Canning
Storage
Sterilization