Effect of high pressure combined with temperature on the death kinetics of Alicyclobacillus acidoterrestris spores and on the quality characteristics of mango pulp

Alicyclobacillus acidoterrestris is a spore-forming microorganism causing flavor changes in acid juices. The objective of the present study was to comparatively evaluate the effects of thermal processing (TP: 82, 84, 87, 90 and 95 degrees C) and high pressure combined with temperature (HPP + T: 600 MPa at 65, 70, 75, 80 and 90 degrees C) by inactivation kinetic modelling of the inactivation of Alicyclobacillus acidoterrestris spores in mango pulp, and also the effects of these processes on the color and stability of the pulp. The Weibull and Bigelow models (first order) demonstrated a good adjustment to the data (R-2 >= 0.96). The D values for HPP + T (e.g., D-600MPa/90 degrees(C) = 1.27 min) were always smaller than those for the thermal treatment (e.g., D-90 degrees(C) = 7.60 min), but the z values for HPP + T were about 5 times higher than for TP. As a consequence of the shorter processing times required to inactivate 5D of spores, the HPP + T process resulted in less color changes (YI, BI, Delta E) and a greater water holding capacity (<= 91 %). These results indicate advantages of using this technology, allowing microbiological safety using a short processing time, favoring better retention of quality characteristics.