Effect of the high hydrostatic pressure on aromatic profiles and inactivation of Escherichia coli O157:H7 in mango nectar

Ataulfo mango (Mangifera Indica L.) is one of the tropical fruits with highest demand due to its nutritional composition and characteristic flavor. However, losses of processed products, due to the presence of bacteria such as Escherichia colt O157:H7, are usually large. E. coli has been considered one of the 10 major pathogens concerned in foods. The use of high hydrostatic pressure technology in the processing of mango nectar would enable to obtain a safety product. The pathogen Escherichia coli O157:H7 was inoculated at 1x10(6) CFU/mL in mango nectar. The inoculated samples were then subjected to high hydrostatic pressure (150, 200 and 250 MPa) for 0, 10 and 20 min at 25, 35 and 45 degrees C. E. colt showed more resistance to high hydrostatic pressure at 25 degrees C than at 35 or 45 degrees C. Complete E. coli inactivation was observed at 150 MPa, 35 y 45 degrees C on day zero (day of treatment) and at 200 MPa, 35 degrees C on day zero and after 6 days of storage. Identification and quantification of chemical species by solid phase microextraction (SPME) of aromatic profiles of untreated and pressurized mango nectar was carried out. It was observed a reduction with the application of temperature in both, ethanol and alpha-Pimene concentration, in counterpart p-myrcene and 3-carene were not affected. The pH and total soluble solids showed no significant difference (p<0.05) with the pressure treatments. The treatment by high pressures allowed the complete inactivation of Escherichia coli O157:H7 without causing a negative effect on the aromatic profile of mango nectar.