A distinguishing quality or characteristics of apple puree was determined considering the effect of different processing practices: thermal (4 T), ohmic heating (OHM) and high-pressure processing (HPP). In the thermal treatment, the flow rate was set to 1700 L/h and SHP was approximately 40 s; HPP was conducted at 600 MPa for 3 min and ohmic heating at a flow rate of 2000 L/h, at 107 °C (sample preheated from 25 to 60 °C). Effects on colour, viscosity, particle size distribution (PSD), total phenol content (TPC), ascorbic acid content and sensorial quality were comparatively studied. Results showed that a very low reduction of ascorbic acid in HPP is observed. The highest ascorbic acid loss was observed for 4 T and in a lower extent for OHM ascribable to the thermal degradation, as hypothesized for pigments. The TPC content was not changed during processing. The other quality parameters evaluated (viscosity, colour, PSD, turbidity, consistency, sensorial analysis) were affected by treatments, with particular reference to 4 T. This is one of the first study applying commercial industrial-scale equipment’s. Concluding, as compared to 4 T, OHM and HPP demonstrated feasible technologies for the treatment of apple puree, having obtained also a good organoleptic response. Apple purée preparation by means of high-pressure processing, ohmic or mild thermal treatments could imply new opportunities for the apple processing industry in developing more fresh like value-added products with reasonable shelf life.
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