Conventional processes of food dewatering, including thermal, have undesirable effects such as destruction of vitamins, aromatic compounds and pigments. In addition, there are some special technological complications and energy consumption. Thus, food concentration processes are directing to non-thermal techniques or methods with reduced heat effects. Superabsorbent, are highly hydrophilic polymer networks which can absorb water and aqueous solutions hundred times more than their weights and retain them in their structures. These materials are subgroups of hydrogel family that form gels after absorbing water. In the present research, the possibilities of yogurt dewatering using these absorbents were investigated for the first time. In experiments carried out, the effect of superabsorbent, type of bed (horizontal and vertical) and time on normal method of yoghurt concentration (use of permeable membrane, were studied. The percentage of dry solids and total soluble solids of dewatered samples were measured in different time intervals up to 180 minutes. The results showed that the use of superabsorbent polymer could reduce the concentration time to one third. On the other hand, in a known time interval, more than 70% increase in the yoghurt dry solid values were observed with a wide or horizontal bed using superabsorbent compared to the present method (without absorbent in a vertical bed). These consequences suggest the application of polyacrylic superabsorbent as an extreme hydrophilic material in the non-thermal food dewatering processes.

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