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A. - Pasteurized milk is a dairy product produced by subjecting the raw milk to a thermal process temperature and time, to ensure the total destruction of pathogenic microorganisms and almost all non-pathogenic microorganisms.

Pasteurization is usually effected at temperatures below 100 ° C and should be followed by rapid cooling. Always interesting to operate at a higher temperature for a shorter time to, obtaining identical results bacteriological, retain a greater degree the original qualities of the product. A liquid acid can be pasteurized at a lower temperature. Pasteurization can be done once the product packaging or prior to this operation.

The pasteurization of the packaged product is mainly used for beer, cider, fruit juices and sometimes, wine bottle packaging. Once closed, the bottles are subjected to a water spray getting hotter, to 65-75 ° C, and kept at this temperature for a time ranging from twenty to thirty minutes, and finally, are cooled by water increasingly cold.

B. - Ultra Pasteurized Milk .- The process of UHT or long term is to subject the product to very high temperatures (140-150 ° C for a period of time very short (1-5 seconds), so that in addition to achieving the total sterility with little modification of the product, minimizing the possibility of further chemical transformations, physical and organoleptic characteristics of food. The valid time for consumption (months) is much higher than in the pasteurized .

This process gives the milk and flavor to cooked due to a mild caramelization of the lactose (milk sugar).