Modeling the polyphenoloxidase inactivation kinetics in pear, apple and strawberry purees after High Pressure Processing

Thermosonication for polyphenoloxidase inactivation in fruits: Modeling the ultrasound and thermal kinetics in pear, apple and strawberry purees at different temperatures

“…All chemicals used were analytical grade: Catechol, polyvinylpolypyrrolidone (PVPP) (Sigma Aldrich, Steinheim, Germany) and Triton X-100 (Ajax FineChemical, Taren Point NSW, Australia). The procedure of Dalmadi et al (2006) for enzyme extraction was carried out and modified according to Sulaiman and Silva (2013) and Sulaiman et al (2015). Unprocessed and processed fruits (10 g) were mixed with 20 mL of 0.2 M sodium phosphate buffer (pH 7.0) and 4% (w/v) insoluble PVPP with the addition of 1% (v/v) triton X-100 and 50 lL of 1 M NaCl, using a commercial blender for 3 min.…”

“…This has been an on-going concern in the food industry and the focus of several research studies (Ferrar and Walker, 1996;Lambrecht, 1995;Martinez and Whitaker, 1995;Queiroz et al, 2008;Silva and Gibbs, 2004;Sulaiman and Silva, 2013;Sulaiman et al, 2015;Vámos-Vigyázó, 1981). Depending on the fruit, the PPO's optimum pH is between 5 and 8 and the optimum temperature is between 20 and 40°C (Dalmadi et al, 2006;Navarro et al, 2014;Siddiq et al, 1993;Wu et al, 2013;Yang et al, 2000).…”

High pressure processing of milk: Modeling the inactivation of psychrotrophic Bacillus cereus spores at 38–70 °C

“…Inactivation of microbial spores and enzymes by high pressure alone is not feasible. Therefore, a combination of HPP with a mild thermal process is required (Patterson, 2005;Sulaiman and Silva, 2013;Sulaiman et al, 2015). Depending on the resistance of the bacterial spores, high pressure (300-700 MPa) combined with temperature (45-100°C) has been successful in inactivating them (Ludwig et al, 1996;Sojka and Ludwig, 1997;Rovere et al, 1998;Okazaki et al, 2000;Lado and Yousef, 2002;van Opstal et al, 2004;Moerman, 2005;Reineke et al, 2013;Luu-Thi et al, 2014).…”

Inactivation of Byssochlamys nivea ascospores in strawberry puree by high pressure, power ultrasound and thermal processing

“…HPP technology, generally with pressures between 400 and 600 MPa at ambient or chilled temperatures, and processing times under 10 min, have been used commercially for the preservation of acidic fruit juices and beverages (Cheftel, 1995). In general bacterial spores, mold ascospores and enzymes in food are difficult to inactivate by HPP alone (Evelyn and Silva, 2015a;Larson et al, 1918;Patterson, 2005;Sulaiman and Silva, 2013;Sulaiman et al, 2015a;Timson and Short, 1965). However, most of the heat resistant bacterial spores, including pathogenic species, do not germinate and grow in the acidic environment (pH b 4.6) of the fruit juices (Silva and Gibbs, 2004).…”