Effetto di alcuni ostacoli fisici e chimici sulla stabilità all'ossidazione e sull'accrescimento microbico di mortadelle confezionate sottovuoto

Mortadella sausages were prepared with a standard mix and a mix containing tomato powder. Both products, sliced and vacuum-packed in plastic trays, were divided into two batches: the first was subjected to isostatic high pressure (600 MPa for 5 min) while maintaining a temperature of 15°C; the second was used as reference. The trays were then kept at 3 and 9°C. At discrete storage times, all samples were subjected to sensory analysis by a trained test-panel and the following Important chemical and physico-chemical parameters were evaluated: colour, colour during exposure to UV-light for 3 hours, rancidity (expressed as TBA parameter) rancidity after 3 hours of exposure to light and residual nitrite and nitrate levels. The decrease in the initial microbial load, due to the high pressures, results in an increase of product stability throughout the storage period at refrigeration temperatures. A lower degradation of the sensory, chemical and physico-chemical characteristics in the HP-treated samples is, in fact, observed in comparison with the reference ones, even though an impairment of some descriptors occurs immediately after treatment. Moreover, the addition of tomato powder improves product stability to oxidation and allows the product to develop typical taste, odour and colour pleasant to the consumer throughout storage.