There are different milk products that are described below here: 1. Cheese 2. Butter 3. Ghee.
A milk product is food produced from the milk of mammals. Dairy products are usually high energy yielding food products. Any of the foods made from milk, including butter, cheese, ice-cream, ghee are the milk products.
1. Cheese:
Cheese is a product which is obtained by draining after the coagulation of milk with a harmless milk coagulating agent. It has a high nutritional value. It is an excellent source of milk protein, calcium, phosphorus, some fat, soluble vitamins like A, D, E and K. D
The success of producing good quality cheese lies in selecting appropriate starter culture and regulating its growth during manufacture to get desirable levels of acid and moisture in the cheese.
Casein is a protein contained in milk. Milk casein is extensively used in many industries. The commercial casein is prepared from the skimmed milk. There are three types of casein, depending upon the coagulating agent used acid casein, rennet casein and lactic casein.
Composition of Cheese:
The average composition of some of the important varieties of cheese is given below:
2. Butter:
Among the milk products, the butter is most important one. Almost in every house throughout the world, it is used in one form or the other. The butter is concentrated form of the milk which contain maximum amount of fat in it. Each gram of fat provides about 9 kilo calories of energy.
Types of Butter:
Many kinds of butter are found in the market. These differ with the type of cream from which they are made and with variations in the manufacturing process.
A brief description of several kinds of butter is given here:
(i) Pasteurised Cream Butter – These are made usually from pasteurised sweet cream.
(ii) Ripened Cream Butter – It is made from the cream which has a pleasant, delicate aroma and is developed before churning by ripening.
(iii) Unripened Cream Butter – It is made from unripened cream. The flavour of such butter is usually mild.
(iv) Salted Butter – It is a butter to which salt has been added.
(v) Unsalted Butter – This type of butter contains no added salt.
(vi) Sweet Cream Butter – In this type of butter, the acidity of the churned cream does not exceed 0.20%.
(vii) Sour Cream Butter – It is made from the cream which has more than 0.20% acidity,
(viii) Fresh Butter – This is a type of butter which has not undergone cold storage.
(ix) Cold Storage Butter – This type of butter can be stored at a temperature of about – 18°C for some time.
(x) Dairy Butter – This butter is made on farm. It is usually made from unpasteurised sour cream which has not been pasteurised for acidity.
(xi) Cream Butter – This type of butter is made in a creamery or dairy factory. It is more uniform in quality than dairy butter.
According to the PFA act table/creamy butter should contain not less than 80% fat, not more than 1.5% curd and not more than 3.0% common salt.
3. Ghee:
It is a class of clarified butter that originated in India and is commonly used in South Asian. Ghee is a type of clarified butter, is prepared by simmering butter and remove the residue. The texture, colour and taste of ghee depend on the quality of the butter and the duration of the boiling.
The pure clarified fat is derived from milk or from curd or from desi (cooking) butter or from cream, without any preservative and colouring matter. It should contain not more than 0.3% moisture and Bandouin test (adulteration test for vegetable fat) should be negative.
The legal standards for ghee are given below:
RM Value – It means the number of mL of deci-normal alkali (KOH) needed to neutralise the steam volatile and water soluble fatty acids obtained from 5 g fat in a standard apparature.
P Value – It means the number of mL of deci-normal alkali (KOH) needed to neutralise the steam volatile and water insoluble fatty acids obtained from 5 g fat in the standard apparature.
K Value – It is the number of mL of deci-normal alkali needed to neutralise the steam volatile and water soluble fatty acids of which silver salts are soluble in water, obtained from 5 g of fat.
S Value – This is the number of mg of potassium hydroxide (KOH) needed for saponification of 1 g fat or oil.
Ghee Preparation:
Ghee is made by several methods. Each method involves heating a milk product to evaporate the water. This concentrates the milk fat and precipitates the non-fat milk solids.
Heating is carried out in three stages:
i. The first stage involves raising the temperature of the product to the boiling point.
ii. The second stage, the free moisture is evaporated.
iii. The third stage, the milk solids other than fat are dried out by the evaporation of the bound water.