EFFECTS OF ULTRA-HIGH HYDROSTATIC-PRESSURE TREATMENTS ON THE QUALITY OF TOMATO JUICE

The effects of ultra-high hydrostatic pressure (UHP) treatments on som e physicochemical, microbiological and sensory properties of single-st rength natural tomato juice were evaluated using response surface meth ods. Application of graphical optimization techniques showed that UHP processing yields products which, beside being microbiologically stabl e, have improved viscosity and colour properties in comparison with th eir conventional heat-processed counterparts. Enzyme inactivation was found to be less than that caused by the conventional hot-break treatm ent. During UHP processing, very high n-hexanal and cis-3-hexenal conc entrations were formed from free fatty acid oxidation.