This study indicated the feasibility of HPCD treatment as low temperature pasteurization of fresh coconut water. The ideal process conditions were determined to be 12 MPa, 40 °C, 30 min and induced about 5 Log reductions of mesophilic microorganisms, lactic acid bacteria, yeasts and molds and about 7 Log reductions of total coliforms. Few differences in the physical–chemical and nutritional attributes were induced by HPCD treatment. No differences were observed in dry matter, soluble solids, sugars and vitamins content although a reduction of its volatile fraction was detected. Nevertheless, FU and HPCD treated coconut water were both clearly distinguished from the HP one.
Overall, the study demonstrated that HPCD technology represented a promising alternative to thermal processing for microbiologically stabilizing liquid foodstuffs without altering their quality attributes.
Acknowledgements
The authors gratefully acknowledge the financial support granted to this work by the University of Trento and Autonomous Province of Trento on “Supercritical Carbon Dioxide Pasteurization of Coconut Water, a Sport Drink with a High Vitaminic and Nutritional Content” (Bando Universiadi 2013).