Dairy Products

The category of Dairy Products includes hundreds of different food products deriving from milking mammals usually cows, sheeps and goats. Milk is considered the most-uncomplete natural and traditional food from nutritional viewpoint. The amazing chemico-physical complexity of milk permits to obtain foods rich in proteins or in fats, lactose (sugars) and minerals, in particular calcium, as a function of processing approach.


Dairy industry is base on the utilisation of the wondering properties of raw milk. Sanitation treatments of raw milk bring to short-term or long-term shelf-life products called respectively pasteurised and sterilised or UTH (Ultra High Temperature) milk types. EU and national legislation impose strict datation to  be printed on milk labels, generally 6 days and 3 months for pasurised and UHT milk respectively. Treatments to santize milk are generally based on thermal treatments in higly efficient heat exchanger and eventually coupled with microfiltration processes on order to prolong the shelf-life (uo to 10 days) without any appreciable sensorial changes. On the other hand cheese making is based mainly on caseins coagulation by acids and/or specific proteolityc enzymes called rennet and this process brings fundamentally to a separation of caseins (including a proportion of milk fat globules) from the milk plasma that include mainly all the more solubles components like lactose (the sugar of milk), minerals and suspensed substances like whey proteins and protein residues and peptides. This ensemble of components in water phase is called whey and it is a valuable milk by-product that can be trated at high temoerature with acids to coagulate the whey proteins that did not flocculate  during cheese making to obtain a nice proteic food known as cottage-cheese. Furthermore, the whey, eventually defatted by centrifugation to reduce the amount of fat remained following the casein coagulation, could be used to design high protein beverages in mixture with fruit juice to  prepare energy drink particularly suitable for sport activities.


This text was prepared by Marco Dalla Rosa of the Università Di Bologna, Department of Food Science, Italy.

For further questions please refer to: marco.dallarosa@unibo.it