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This book discusses the transformation of milk into high-quality produces, emphasizing the principles of physical, chemical, enzymatic, and microbial transformation. The text begins with an introduction to the chemistry, physics and microbiology of milk and then explains the manufacturing processes. After an extensive discussion of various dairy products and the procedures necessary for consumer safety, the book concludes with details on the manufacture and ripening of cheese.

Presence of lipase in milk, curd, whey and cheese was studied. A small amount of the product was added to a large volume of lipase-free whole milk that had been made sensitive to lipolysis by homogenization. Increase of the acidity of the fat in the mixture, determined after incubation, was interpreted as enzyme activity being present in the product concerned. Results obtained in this way showed that lipase was present in raw milk and in the curd and whey made of it, but that the bulk of the enzyme disappeared quickly from the curd during Gouda cheese making, as a result of several factors including scalding of the curd, whey removal and pH decrease. By using this method no lipase could be detected in ripened Gouda cheese, made of raw milk. Furthermore, no potential lipolytic activity was measured in ripened danish blue cheese, but it was in ripened Camembert and Brie, all of these cheeses being made of pasteurized milk. Obviously, the presence of active milk lipase in ripening cheese is by no means self-evident.

This book covers the chemistry, physics, and microbiology of milk; the main unit operations applied in the manufacture of milk products; and procedures to ensure consumer safety, product quality, and efficient processing. The final section is devoted to describing the processes and interactions unique to the manufacture and maturation of cheese.

In deze overzichtspublikatie is naast een algemene beschouwing een uiteenzetting gegeven van: de structuur van kaasstremsel en zure melk coagulaten in relatie tot de eigenschappen van de caseinedeeltjes en de wijze van coaguleren. Verder over methoden voor het schatten van het verloop van het coagulatieproces onder verschillende omstandigheden. Tenslotte zijn enkele andere factoren weergegeven, die het watergehalte van wrongel beinvloeden

In experiments on the brining of cheese, displacement of salt in cheese could be adequately described by a diffusion process. A simple model on the structure of the cheese matrix (fat globules and protein), allowing for friction and labyrinth effects, explained the lower value for the pseudo diffusion coefficient ( D *) of sodium chloride in the moisture, than the true diffusion coefficient in pure water.The transport ratio of water to salt was usually constant within one cheese. it was always more than one, presumably because of the difference in friction of the components. With the values obtained for D * and moisture loss, total salt uptake by cheese could be calculated.With calcium-free brine, moisture in cheese locally increased and a soft rind developed; with brine containing calcium chloride, the rind was firm and its moisture content low. Preliminary experiments on swelling are described.Not all the water in cheese is active in salting. For salt, there was less non-solvent water than for lactose. A possible explanation is discussed.