Effect of High Pressure Processing and refrigerated storage on the shelf life of minimally processed peaches

DENOYA GABRIELA; POLENTA BUSTAVO; SOTERAS TRINIDAD; CAP MARIANA; SANOW CLAUDIO; VAUDAGNA SERGIO R.

Columbus, Ohio

Workshop; 2014 International Nonthermal Food Processing Workshop; 2014

Ohio State Univesity

Minimally processed (MP) products constitute an easy way for modern lifestyle to include fruits and vegetables in everyday meals. However, due to their perishable condition and the few preservation processes available that can ensure their requirement of freshness, the shelf life of these products is usually short. High Pressure Processing (HPP) could be a suitable alternative to preserve them, since it is less aggressive than thermal treatments. The aim of this work was to evaluate the effect of HPP and refrigerated storage on the shelf life of MP-peaches. Cylinders of Prunus Persicae cv. SummerSet were pre-washed and immersed during 2min in 1%ascorbic acid and 1%citric acid. Subsequently, cylinders were vacuum-packed in CryovacBB2800 bags. Four treatments were studied: HPP (600MPa for 5min at room temperature): A-stored at 4°C (HPP-4°C) and B-at 20°C(HPP-20°C) and non-pressurized samples: C-stored at 4°C (control-4°C) and D-at 20°C (control-20°C). Different evaluations were carried out over the samples at 1,14, 28 and 42days of storage: Browning potential, Texture Profile Analysis, activity of polyphenoloxidase (which catalyze browning), ethanol content (related to fermentation processes), sensory and microbiological analysis. During storage,texture parameters of HPP-4°C samples were the best (p<0.05) preserved. Polyphenoloxidase activity and browning potential were significantly (p<0.05) diminished by HPP and this behavior was the same for all the days and temperatures evaluated. Ethanol content was significantly (p<0.05) higher in control samples and increased at a faster rate during storage at 20°C. Sensory analysis showed non-significant differences among samples until day 42.Moreover, no growth of both aerobic and lactic acid bacteria was detected in any of the samples. In case of molds and yeast counts, only at day 42, control-20°C samples presented 7,31logUFC/g on average. In conclusion, pressurized samples stored at 4°C were better preserved in terms of browning development and texture, without microbiological spoilage and sensorial alteration