INTRODUCTION• Milk is defined as the whole, fresh, clean, lacteal secretion obtained by the complete milking of one or more milch animals.• In India, the term ‘milk’ refers to cow or buffalo milk, or a combination of the two.• India is the largest producer of milk and as per National Dairy Development Board (NDDB)’s estimation, the country produced 102 million MT of milk in 2007-08 with annual worth of Rs. 1,232 billions.
SPECIAL TYPES OF MILK• Under the category of special milk are included those processed milk products which physically resemble and behave like liquid milk.• These processed milk products are:- Standardized milk Homogenized milk Sterilized milk Flavored milk Toned milk & Double toned milk.
STANDARADIZED MILK• Standardized Milk is milk in which the original fat and also the ratio of fat to the milk solids content has been changed either by:-1. the removal of milk fat, or2. the addition of skim milk, or3. the addition of cream.• According to PFA rules (1976), standardized milk should contain:-1. Minimum fat %- 4.5%2. Minimum SNF %- 8.5%
CALCULATION REGARDING STANDARDIZATION OF MILK• The Pearson’s square is used to calculate the relative quantities of materials required for standardization.• The Pearson’s square method can be understood by following example:- Given that the fat percentage of cream is 28% and milk is 3%. How many kg of cream and milk will be required to make 500 kg of milk testing 4% fat? sol. 28.0 1.0 4.0 3.0 24.0 25.0
=>1.0:25.0 = C:500,where C is cream required in kgsor 1/25 = C/500or C= 500/25⇒ C= 20 kgs⇒ milk required= 500-20 = 480 kgs
HOMOGENIZED MILK• Homogenized Milk is milk which has been treated in such a manner as to insure breakup of the fat globules to such an extent that after 48 hours quiescent storage no visible cream separation occurs on the milk.• Homogenization refers to the process of forcing the milk through a homogenizer with the object of sub- dividing the fat globules.• In efficiently homogenized milk, the fat globules are subdivided to 2 microns or less in diameter.
FLOWSHEET FOR HOMOGENIZED MILK MANUFACTURING Receiving milk Cooling to 5°C and bulk storage Pre-heating(35-40°C) Filtration/Clarification Cooling to 5°C Standardizing and storage(5°C) Pre-heating(60°C)
Homogenization Single stage homogenization Two stage homogenization(2500psi at 60°C for milk with fat (2000 psi at first stage & 500psi at upto 6%) the second stage for milk with more than 6% fat) Pasteurization(holder or HTST) Cooling(5°C) Bottling Storage(5°C)
STERILIZED MILK• Sterilized Milk may be defined as milk which has been heated to a temperature of 100°C or above for such lengths of time that it remains fit for the human consumption.• The above definition does not always mean that treated milk must be completely free of bacterial spores.
FLOW SHEET FOR STERILIZED MILK MANUFACTURINGA. IN-BOTTLE STERILIZATION:- IN- Receiving milk Cooling to 5°C & bulk storage Pre-heating(35-40°C) Filtration/Clarification Cooling to 5°C Standardizing & Storage(5°C) Pre-heating(60°C)
TYPES OF STERILIZERSA. For in-bottle sterilization:- The sterilizers used for in-bottle sterilization are:- Batch sterilizers Continuous sterilizers
B. For UHT sterilization:- Two types of sterilizes are used for ultra high temperature sterilization of milk. These are:- Sterilizers operating with direct steam heating. Sterilizers operating with indirect steam heating.
FLAVOURED MILK• Flavoured Milk is a milk to which some flavours have been added.• When the term ‘milk’ is used, the product should contain a milk fat %age at least equal to the minimum legal requirements for market milk.• When the fat %age is lower i.e. 1-2%, the term ‘drink’ is used
TYPES OF FLAVOURED MILK• Chocolate milks/drinks:- The ingredients used for chocolate milk/drink are: Cocoa powder- 1.0-1.5% Sugar- 5.0-7.0 % Sodium alginate(stabilizer)- 0.2%
• Fruit flavoured milks/drinks:- Permitted fruit flavours/essences, together with permitted matching colours and sugars are used. The common flavours used are strawberry, mango, vanilla, banana etc.
TONED MILK• Toned Milk refers to milk obtained by the addition of water and skim milk powder to whole milk.• In practice, whole buffalo milk is admixed with reconstituted spray dried skim milk powder for the production of toned milk.• Under PFA rules(1976), toned milk should contain a minimum of 3.0% fat & 8.5% solids-not-fat throughout India
FLOWSHEET FOR TONED MILK MANUFACTURING Receiving of water in pasteurizing vat Pre-heating(38-43°C) Addition of skim milk powder Mixing Addition of whole buffalo milk Mixing Filtration Pasteurization(63°C/30 minutes) Cooling(5°C) Packaging & Storage(5°C)
DOUBLE TONED MILK• Double Toned Milk is milk which is also obtained by the addition of water and skim milk powder to whole milk.• Under the PFA rules(1976), Double Toned Milk should contain a minimum of 1.5% fat 9.0% solid-not-fat throughout India.
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