Milk is considered as the primary source of nutrition for neonates who cannot digest other foods. Milk at early stage of lactation is called as colostrums having antibodies which are necessary for babies, until immune system develops sufficiently to prevent newborn babies from the risk of many diseases. Generally during the early stage of growth, neonates consume mother milk typically for 6–24 months but in some special cases they consume milk from several alternative sources.
Although milk from several species such as buffalo, sheep, goat and camel has also been studied scientifically for several decades, cow milk is considered to have given vast benefits to human health and nutrition because of its resemblance to human milk composition. Bovine milk is a complex heterogeneous fluid, which consists of distinct essential nutrients such as fat globules, proteins, minerals and several other minor components. Typical milk composition includes about 87% water and 13% milk solids, where milk solids are further classified into 3.7% fat, triglycerides, esters and amino acids and 8.9% non-fat solids. Non-fat solids are a mixture of proteins (3.4% caseins and whey) and lactose 4.8% and all other minerals and minor components 0.7%. Milk contains a large number of bioactive components including glycolipids, growth factors, oligosaccharides, vitamins, hormones, growth factors, proteins and peptides. Milk proteins have positive effects on human health. Milk proteins have been studied and are characterized in terms of their structure and functional properties.
The constituents of milk are specific for different mammalian species making it symbolic for the neonatal requirements of its progeny. It provides the newborn with maximum nutrients during the initial growth period. So it is complete diet according to nutrient requirements of infants. Among Asian countries Pakistan ranks fourth with respect to goat population and third with respect to milk production. In Pakistan total number of goats is 6 corer and 15 laces and there are thirty four breeds. Milk has been a part of the human diet for millennia and is valued as a natural, traditional and an affordable food. Milk and milk products play an important role in dietary quality and it provides a substantial amount of vitamins and minerals in relation to its energy contents. Milk protein has a sufficient amount of notional value beneficial for human health. It has an antioxidant property and improved the human immunity system against different diseases.
Proteins and peptides present in goat milk have important nutritional, functional, technological and biological characteristics. Casein protein has an appropriate amino acid composition which is necessary for the growth of infants. Whey protein has high nutritional value and is used as protein supplement in the production of dietary products for patients suffering from pulmonary disease or renal insufficiency. Goat milk fat has more vitamin A as compared to milk obtained from cow. The fatty acid constitution of goat milk is also different due to higher concentration of volatile fatty acids (caproic, caprylic and capric) that are responsible for the particular taste and odour of the specific dairy products.
|Species||Water %||Fat %||Protein %||Total Solid %||SNF %||Lactose %||Ash %|
Goat Milk Composition (Jensen, 1995)
Dairy farming is the fundamental part of our country and other middle east like countries in which Italy, Spain, and France. However on large scale the products obtained from milk of goat are not available in abundance. Goat milk is used in different type of food products which include cheese and many fermented products such as kefir, yogurt. Commercially several brands of milk products obtained from goats are present in the market. In many parts of the world goat milk plays an important role. The population of goat is about 6.2 million which have rank third among total animal population. In recent years the interest of goat milk application is increasing internationally.
Infant formulas are used when there is not sufficient breast milk or breast-feeding is not possible. Goat milk provides a substitute base for the production of infant formulas, as it have relatively lower hypersensitivity, easier digestion and physiological advantages, compared to other types of milk. The amount of lactose in bovine and goat milk is similar, but Alpha-s1 casein which is only present in ruminant milk is found in much lower concentrations in goat compared to bovine milk. Goat milk contains higher concentrations of nucleotides, polyamines and some of the essential amino acids. Goat milk also contains non-nutritional components, such as oligosaccharides; in different concentrations that possible play a role in the different effects on formula feeding.
There are certain vitamins present in goat milk. Goat milk has higher vitamin A as compared to cow milk, with values 340l U/kg and 230l U/kg respectively. Goat milk has more tocopherol with values 34.8ug/g. Vitamin C content is also present in buffalo milk in range of 23-30 mg/kg. Thiamine, nicotinic acid, biotin and folic acid are present in buffalo milk in 0.5, 2.6, 26.8 and 0.1 µg/ml respectively.
Wahab Ali Khan1, Dr. Sajjad-ur-Rahman2, Dr. Muhammad Saeed1and Muhammad Azam1
1National Institute of Food Science & Technology, University of Agriculture Faisalabad.
2Faculty of Veterinary Science, Institute of Microbiology, University of Agriculture Faisalabad.