Optimizing High Hydrostatic Pressure Processing for fresh-cut peaches preservation

DENOYA GABRIELA; POLENTA GUSTAVO; SANCHO ANA MARÍA.; BUDDE CLAUDIO; SANOW CLAUDIO; VAUDAGNA SERGIO R.

Florianopolis

Workshop; 2013 International Nonthermal Food Processing Workshop; 2013

EMBRAPA

High Hydrostatic Pressure Processing (HPP) is proposed like a less aggressive alternative to thermal treatments for preservation of fruit products. The aim of this work is to optimize HPP (pressure level-holding time) for minimally processed peaches to achieve enzyme inactivation while preserving texture and color. Cylinders of Prunus Persicae cv.Flavorcrest were washed and immersed during 2 min in HClO 200 ppm solution, for superficial decontamination and then in 1% ascorbic acid and 1% citric acid for initial inhibition of enzymatic browning. Subsequently, cylinders were vacuum-packed in Cryovac BB2800 and processed with Stanted Fluid Power Ltd. HHP equipment according to different treatments arranged in a Doehlert design of two factors: time (1-5-9min) and Pressure level (400-450-500-550-600MPa) at room temperature. Afterwards, different determinations were carried out with the samples: Chromatic parameters of CIE L*C*h, Texture Profile Analysis (TPA) and microstructure analysis, to evaluate the fruit physical quality; activity of polyphenoloxidase (which catalyze browning) and alcohol dehydrogenase (related to induction of fermentation in anaerobic conditions), to evaluate enzyme inactivation. A Regression Model was adjusted for each parameter. Finally, a Principal Compounds Analysis and a desirability study were performed showing that among the treatments studied, the best was 600MPa for 5min and the optimal treatment would be 585 MPa -1 min. Higher levels of pressure are more effective in inactivation of enzymes than longer times, which additionally affect the firmness of tissues.