Kinds Of Milk

KINDS OF MILK
MILK AND DAIRY PRODUCTS QUALITY AND PROCESSING

RAÏSA VILA I SEMPERE LARA CATALUÑA MARTÍ

INDEX 1. CHARACTERISTICS OF THE MILK 1.1. PHYSICAL-CHEMICAL PROPERTIES OF MILK 1.2.TECHNOLOGICAL PROPERTIES OF MILK 1.3. ORGANOLEPTIC PROPERTIES OF MILK 2. MILK COMPOSITION 3. KINDS OF MILK 3.1. CASEIN MILK 3.2. ALBUMIN MILK 3.3. COLOSTRUM MILK 3.4. NORMAL MILK

1. CHARACTERISTICS OFTHE MILK Milk: fat emulsion in water, stabilized by a protein coloideal dispersion in a solution of salts, vitamins, peptides, lactose, oligosaccharides, casein and other proteins. Milk also contains enzymes, antibodies, hormones, pigments (carotenoids, xanthophylls, riboflavin), cells (epitetales, leukocytes, bacteria and yeasts), CO2, O2 and nitrogen. 1.1. PHYSICAL-CHEMICAL PROPERTIES OF MILKDepend on the milk components content and their interactions physical-chemical equilibrium. Breach of this equilibrium: ● abnormal milk storage and processing ● pathologic state of dairy cows - DENSITY: It should have a density of 1.028 - 1.032 g/cm3. It depends on the milk composition more fat. - ACIDITY: depends on the concentration of hydronium ions H+ pH (negative logarithm of H+ concentration)depends on citrates, phosphates and caseinates contents normal milk pH 6.4 – 6.8 [the most usual value pH = 6.6]. - FREEZING POINT: the only reliable parameter to check for adulteration with water varies from -0.54 to -0.59 °C the most important change is a fall in lactose and a rise in chloride contents UHT treatment or sterilisation will cause the FP to rise average value is -0.550 °C. - OSMOTICPRESSURE: controlled by the number of molecules or particles, not the weight of solute (the smaller the molecules the higher the osmotic pressure) ● milk is formed from blood (they have the same osmotic pressure) ● milk is isotonic with blood Total osmotic pressure is 6.78 atm. 1.2.TECHNOLOGICAL PROPERTIES OF MILK - FERMENTABILITY: ● lactose fermentation ○ lactic acid bacteria ○ inhibitioncompounds ● fermentation activity - COAGULATION: ability to be coagulated by rennet - THERMOSTABILITY: ● ability to maintain its original colloidal properties at high temperatures ● time to the beginning of coagulation at certain temperature depends on: chemical composition of milk and processing conditions optimal thermostability at pH 6.5 – 6.6.

1.3. ORGANOLEPTIC PROPERTIES OF MILK The particles offat and milk proteins are responsible for color, texture and tone of white (opalescence). - TASTE: ● sweet - lactose ● overall flavour – also milk fat and phospholipids ● off-flavour – some components from feed sensory analysis after pasteurisation - SMELL (AROMA): milk after milking does not have any special smell (aroma) it easily accepts smells from surrounding. - APPEARANCE AND COLOUR: Thecolor is also a result of light scattering by the protein, fat, phosphate and calcium citrate. Homogeneous quality of milk white colorationincreases, as the fragmented particles reflect more light, while the skim milk has abluish color due to the smaller amount of large particles in suspension. - opacity of milk – suspended particles of fat, protein and certain minerals - colour - slightly creamy,varies from white to yellow milk contains two pigments: ● carotene ● riboflavin skimmilk is more transparent, with a slightly bluish tinge. - CONSISTENCY: done by high water content and homogenous structure.

4. MILK COMPOSITION
● Proteins: are responsible for forming the structure of our body. In milk are albumin, globulin (very important for newborns) and casein. The latter is an exclusivemilk protein containing all essential amino acids we need. ● Carbohydrates: are great natural sources of energy. Milk contains lactose, consisting of glucose and galactose. Its sweetening power isvery low, which delays the tiredness. ● Fats: These are substances that provide energy reserve energy and vitamins. ● Vitamins: allow smooth functioning of our body. In milk are especially vitamin B2, B12...