Dairy by-products are formed during the formation of main products like buttermilk, skim milk, whey etc.

2. DAIRY BY-PRODUCT
A dairy by-product may be defined as a
product of commercial value produced
during the manufacture of a main
product.
CLASSIFICATION:
MAIN PRODUCT BY PRODUCT
CREAM SKIM MILK
BUTTER BUTTERMILK
GHEE LASSI
CHHANA/ PANEER
WHEY
CHEESE
CASEIN

3. PRINCIPLE OF UTILISATION
BY-
PRODUCT
PRINCIPLE UTILISATION FOOD PROUCTS MADE
SKIM
MILK
PASTEURISATION FLAVOURED MILK
FERMENTATION CULTURED BUTTERMILK
CONCENTRATION SWEETENED
CONDENSED MILK
DRYING DRIED SKIM MILK
COAGULATION COTTAGE CHEESE
CASEIN
BUTTERM
ILK
FERMENTATION AND
CONCENTRATION
CONDENSED
BUTTERMILK
DRYING DRIED BUTTERMILK
COAGULATION SOFT CHEESE
WHEY FEMENTATION WHEY BEVERAGE
YEAST WHEY
CONCENTRATION CONDENSED WHEY
SWEETENED
CONDENSED WHEY
WHY PROTEIN
CONCENTRATE
LACTOSE

4. METHODS OF UTILISATION
i. Skim milk is the byproduct obtained during
manufacture of cream.
ii. It is rich in SNF and has high nutritional
content.
iii. It is utilized in the standardization for the
manufacture of main dairy products or
preserved by removing moisture in spray
dried form.
iv. It is not regarded as by-product when
consumed in either of these two forms or
consumed as liquid.
v. It is regarded as by-product only when it is
either not economically utilized or utilized
for derived by products like casein and
related products.

6. FLAVOURED
MILK
RECEIVING MILK
STANDARDISATION (Fat content above
1-2%)
PRE-HEATING (60°C)
HOMOGENISATION 2500psi
CLARIFICATION
MIXING COCOA (1-1.5%), SUGAR (5-
7%), STABILISER (0.2%)
PASTEURISATION (71°C/30min)
COOLING (5°C)
BOTTLING AND STORAGE (5°C)
Flavored milks
are milks to
which some
flavors have been
added.

8. CULTURED
BUTTERMILK
• Skim milk should be free
from antibiotics and
inhibitory substances.
RECEIVING SKIM MILK
(SNF 9-10%)
FILTRATION
PASTEURISATION (82-
88°C/30min)
COOLING (22°C)
• Bulk lactic culture (culture
species Streptococcus lactis, Str
cremoris, Str diacetilactis) is
added and mixed thoroughly.
INOCULATION (1%)
INCUBATION (21-22°C)
• CREAMING- cream imparts a rich
flavor, decrease the viscosity.
COAGULATION
(12-16h) (0.80-
0.85% TA)
• ADDING BUTTER GRANULES-
by passing hot butter oil through
screen into cold buttermilk or by
churning culture cream and add them
to cultured skim milk.
BREAK UP
COAGULUM
COOLING (5-
10°C)
PACKAGING AND
STORAGE (5-10°C)
This is obtained by
inoculation an
incubation of
pasteurized skim milk
with lactic starter.

10. SWEETENED
CONDENSED
SKIM MILK
The product is obtained from cow
or buffalo skimmed milk or their
combination by the partial
removal of water and after
addition of cane sugar.
It should contain not less than
26% of total milk solids and not
less than 40% cane sugar.
The fat content should not exceed
0.5% by weight.

11. RECEIVING MILK
FILTRATION/CLARIFICATION
(38-40°C)
• Establish the desired ratio of FAT:SNF
• Establish the desired ratio of sugar to
the total milk solids.
• Adjusts the concentration to desired
percentage of total solids.
STANDARD
ISATION
PRE HEATING
(115-118ºC/ NO
HOLD)
• For preserving the condensed milk.
• Sugars such as sucrose, corn syrup,
glucose are added.
• 40-45% of sugar is added
ADDITION
OF SUGAR
• Removal of water from milk by
boiling it under partial vacuum
at a low temp till the desired
conc is reached.
CONDENSING
• Quick cooling is desirable to
delay the tendency of age –
thickening& discoloration.
• For relative smoothness of
condensed milk, the optimum
temp of about 30-40ºC/1hr
under vigorous agitation after
which it is cooled rapidly for
packaging.
COOLING AND
CRYSTALLLISATI
ON
PACKAGING
• Cool storage is important to
prevent defects such as
sandiness, sugar separation,
viscosity changes.
STORAGE (10ºC)

13. COTTAGE CHEESE
This is a soft, unripened cheese usually made
from skim milk
It has mildly acid flavor.
It consists of small particles or flakes f curd
which have meaty consistency (when made
from rennet curd).
TYPES OF CURD CHARACTER
OF CHEESE
ACID (Milk is coagulated with
lactic acid develop by the action of
lactic starter)
1. SMALL
PARTICLES
2. EXTREMEY
ACID
FLAVOR
3. LOWER
YIELD
RENNET (Milk is coagulated by
the action of rennet in presence of
lactic acid, developed by the action
of lactic starter)
1. LARGE
PARTICLES
2. MILDLY
ACID
FAVOUR
3. HIGHER

14. RECEIVING OF MILK
(PASTEURIZED)
• To restore the conc of Calcium ions
(lowered due to pasteurization) for
formation of desired firm curd
ADDING
CALCIUM
CHLORIDE
• Ripening of cheese is done by addition of
starter for the formation of desirable curd,
growth of favorable bacterial flora,
controlling moisture.
• Starter usually contains Str lactis, Str
cremoris.
• Amount of starter added is 1% of milk at
30°C.
ADDING
STARTER
ADDING
RENNET
(0.2% OF
MILK)
• Setting refers to liquid milk changing to a
semi solid junket.
• First signs are that bubbles of air stirred
into the milk surface takes longer to break.
SETTIN
G
• At cutting, the desirable acidity is 0.5% (pH
4.6)
• Curd should be free from curd particles
CUTTING
• Cooking at 46°C for 2hrs until curd becomes
firm enough to remove wheyCOOKING
• Whey is remove from the curd cubes an
then squeezed gently show slight elasticity.
DRAINAGE
OF WHEY
• 1st wash at 21C, quantity twice the volume
of curd vat, soaking for 15min, the wash
water is removed
• 2nd wash at 16°C in same quantity and then
drained from perforated racks.
• this makes curd firmer.
• Removes acid-hey around it and helps
produce the desired mildness in flavor
WASHING
AND
DRAINING
SALTING
(1% OF
CURD)
PACKAGED AND STORED (5-10°C)

16. CASEIN
Casein is isolated from skim milk.
Uses of edible casein in various
food products such as ice creams,
coffee whiteners, imitation milk,
whipping powders, water binders
in sausages and protein
hydrolysates.
Uses of industrial casein such as
Rennet Casein is used as plastics
for making buckles buttons,
umbrella handle; acid casein is
used as adhesive, paper coating,
paint etc.
CASEIN

17. RECEIVING OF
SKIM MILK
• At 4.1-4.3 pH calcium
caseinate dissociate.
• The casein coagulates as
watery, gel like curd.
PRECIPITATING
• At least 3 separate washings of curd in
water of pH for 15-20min
• Than washing with hot water at 71-77°C
for reducing bacterial count
• Last washing with neutral water at 41°C.
DRAINING
AND
WASHING
• Reduce the moisture level to 55%PRESSING
• To produce particles of uniform size and
surface for drying
• To prevent microbial growth
MILLING
AND
SPREADIN
G
• The intake air temp ranges from 71-77°C
while outlet temp should range from 52-57°C
• To avoid risk of discoloring and impairing its
solubility
• Moisture content is reduce to less than 8%.
DRYING
• After cooling casein is passed through
screens of particular mesh size.
GRINDING
• Packaged in gunny bags lined inside with
closely wooven bags or
• Heavy 3 ply paper bags with polyethene
liners
PACKAGI
NG
STORAGE (in dry
storage room)

18. REFRENCES
• Outlines of Dairy Technology,
Book by De Sukumar
• Technological advances in the
utilization of dairy by products,
2008; NDRI.
• Utilization of by-products of the
dairy. By Henry E. Alvord, C. E.,
Chief of the Dairy Division,
Bureau of Animal Industry.
REFERENCES