MILK
• Breast milk or mother's milk is milk produced by the mammary gland, located in the breast of a human female.
• Breast milk is the primary source of nutrition for newborns, containing fat, protein, carbohydrates (lactose and human milk oligosaccharides) and variable minerals and vitamins.
• Breast milk also contains factors that are important for implications protecting the infant against infection and inflammation, whilst also contributing to the healthy development of the immune system and gut microbiome.
FUNCTIONS
• The breast milk microbiome contributes to the gut colonisation of the infant.
• Relative abundance of Bifid bacterium in the milk plays a major role in immune development.
• Milk derived exosomes exhibits various health effects by transporting bioactive molecule, such as DNA, mRNA, miRNA, lipids and proteins.
• Milk derived exosomes protect intestinal epithelial cells from oxidative stress by regulating cell proliferation and inflammation and exert various functions in immunomodulation and cancer
• Breast milk is rich in miRNAs, short , non-coding RNAs of 18 to 25 nucleotides in length, involved in the development , differentiation, proliferation, metabolism and death of cells and tissues.
TYPES
1. Colostrum
· Colostrum is the first stage of breast milk.
· It occurs during pregnancy and lasts for several days after the birth of the baby.
· It is either yellowish or creamy in color and thick.
· It is high in protein, fat-soluble vitamins, minerals, and immunoglobulins.
· Two to four days after birth, colostrum will be replaced by transitional milk.
2. Transition milk
· Transitional milk occurs after colostrum and lasts for approximately two weeks.
· The content of transitional milk includes high levels of fat, lactose, and water-soluble vitamins.
· It contains more calories than colostrum.
3. Mature milk
· Mature milk is the final milk that is produced.
· 90% of it is water, which is necessary to keep the infant hydrated.
· The other 10% is comprised of carbohydrates, proteins, and fats which are necessary for both growth and energy.
There are two types of mature milk:
1. Fore-milk: This type of milk is found during the beginning of the feeding and contains water, vitamins, and protein.
2. Hind-milk: This type of milk occurs after the initial release of milk. It contains higher levels of fat and is necessary for weight gain.
COMPOSITION
• Human milk composition is dynamic
• it is primarily composed of water, carbohydrate, lipids, proteins etc
• Milk is composed of nutritional component and bioactive component
• Nutritional component include macronutrients like water, carbohydrate, fat, proteins and micronutrients like vitamins and minerals
• The bioactive component include growth factor and immunological factor.
DIFFERENCE BETWEEN HUMAN AND NON-HUMAN MILK
• Nevertheless the compositions are more or less same in both milk types there are some considerable differences can be found.
• Human milk is obviously thinner and sweeter than cow’s milk.
• Human milk contains a high amount of antibodies, specific to the human child.
• Human milk is easily digested by human infants, and they cannot digest cow milk in similar efficiency.
• Cow’s milk have more leucine and protein than the human milk (cows have 3.3% leucine, humans have 0.9% leucine)
• Human milk contains the fatty acids (arachidonic acid and docosahexaenoic acid) while cow’s milk does not contain these fatty acids.
• Whole cow’s milk has almost the same amount of fat as human milk.
FORENSIC SIGNIFICANCE
1. Identification of species in milk and other dairy products by direct PCR technique and Capillary electrophoresis.
2. Degree of drugs passage into breast milk to infant through feeding.
3. Poisoning due to Adulteration of milk like urea, formalin, detergents, ammonium sulfate and boric acid etc.
4. Allergy caused by milk and other dairy products in some of adults and children, due to lactose intolerance.
5. Determination of difference in human and animal milk by the presence of anti-infective properties. (In human it is present and in animal it is absent).
6. Extraction of DNA from breast milk by PCR technique.
7. Identification of risks for the baby include exposure to infectious diseases like HIV, or to chemical contaminants such as illegal drugs from breast milk of donor mother.
8. Estimation of protein denaturation in frozen milk by the effects on casein and fats. (Casein cause allergy on body's immune system; mistakenly thinks the protein is harmful, produces allergic antibodies for protection)
9. Determination of genetic variation that affect human milk composition.
Study and Written By:
Ms Fadiya Keloth
Volunteer of AFRS
