The analysis of the shrinkable phenomena in the course of vacuum drying of cheeses

The study is devoted to the research of shrinka-ble phenomena in vacuum dehydration of cheeses of brands Soviet and Dutch. The dependences of coefficient of shrinkage of cheeses on initial mass fraction of moisture were received. It was revealed that increasing mass fraction of moisture of cheese caused the increase of coefficients of shrinkage of the product. The greatest increase in the coefficient of shrinkage of cheeses was observed at the mass fraction of moisture more than 50 %. The depend-ence of the size of coefficient of shrinkage on initial mass fraction of moisture of cheeses in the course of vacuum drying was established. Moisture con-tent in superficial and central layers of cheeses at vacuum drying was analyzed. It was established that at the increase in temperature, thermal loading moisture content quickly decreased by surfaces of cheeses, meanwhile in the central layers it changed more slowly. The shrinkage at the increased tem-perature was less; however, dry cheese had big mass fraction of moisture. It was revealed that the increase in the difference of mass fraction of mois-ture between internal and surface layers was fol-lowed by the increase in the difference between valid and possible shrinkage corresponding to the amount of the deleted liquid. The coefficients of volume shrinkage of cheeses were calculated: for cheeses Soviet and Dutch they were within 0.017-0.004 and 0.006-0.003 respectively. During analyt-ical pilot studies the dependences of coefficients of shrinkage of cheeses on the thickness of layer of drying, the form and the amount of crushing were received.