Inactivation of Staphylococcus spp. strains in whole milk and orange juice using ultra high pressure homogenisation at inlet temperatures of 6 and 20°C

Inactivation of foodborne pathogens in raw milk using high hydrostatic pressure

“…coli, Salmonella, Shigella and S. aureus are foodborne pathogens of concern for the dairy industry, and raw milk has been identified as an important vehicle for the transmission of these pathogens and been implicated in outbreaks (Brinez et al, 2007;Chapman, 1993;Rajeev Kumar, 2010;Rodriguez, Arques, Nunez, Gaya, & Medina, 2005;Tambekar DH., 2006). Heat treatment is one of the most efficient and economical processes for achieving microbial inactivation in milk, however, it cannot be used to treat heat-labile food and compounds.…”

“…The viability test was performed according to the previous methods (Brinez, Roig-Sagues, Herrero, & Lopez, 2007;Patterson et al, 1995) with some modifications. Briefly, the diluted milk samples were prepared and plated in duplicate in LB, TSA-YE (Beijing Land Bridge Technology Co, Ltd.,), TSA-YE þ NaCl (3%) and TSA-YE þ NaCl (10%) plates, and incubated at 37 C for 24 h, the morphology of the colonies was monitored to assess the lethality and the level of injury caused by HHP treatment.…”

Inactivation of Listeria monocytogenes and Salmonella enterica serovar Senftenberg 775W inoculated into fruit juice by means of ultra high pressure homogenisation

“…This treatment differs from static high pressure in that microorganisms are subjected to a combination of shear forces (being caught between liquid flow paths of greatly differing velocities), cavitation shock waves (from the collapse of holes formed by vaporization within the liquid) and impingement (striking hard surfaces) (Lacroix, Fliss, & Makhlouf, 2005;Tahiri, Makhlouf, Paquin, & Fliss, 2006). The potential of UHPH as alternative to heat pasteurisation to inactivate foodborne pathogens has been demonstrated in milk (Briñez, RoigSagués, Hernández, & Guamis, 2006a,b;Briñez, Roig-Sagués, Hernández, & Guamis, 2007;Vachon, Kheadr, Giasson, Paquin, & Fliss, 2002). Important reductions of E. coli O157:H7 and Listeria innocua have also been reported in orange juice (Briñez, Roig-Sagués, Hernández and Guamis, 2006a;Tahiri et al, 2006).…”

Opportunities for Ultra-High-Pressure Homogenisation (UHPH) for the Food Industry

“…For inoculated orange juices, destruction rates were higher than 5 log units for Lactobacillus plantarum and Saccharomyces cerevisiae [6] and of about 3 log units for different Staphylococcus strains [4]. Inoculated L. monocytogenes and Salmonella enterica were reduced from to 2 to 5 log cycles both in orange and in grape juices [86].…”

“…Fat content of milk has been observed as a key factor in lethality of inoculated Listeria monocytogenes by UHPH technology; it is thought that fat content increases the maximum temperature reached during UHPH treatment contributing to the lethal effect [61]. The inlet temperature (6 or 20°C) and the inoculated Staphylococcus' strain influenced significantly the lethality level of UHPH-treatment with highest levels for S. aureus in whole milk at an inlet temperature of 20°C [4].…”