Ohmic heating increases inactivation and morphological changes of Salmonella sp. and the formation of bioactive compounds in infant formula. (August 2021)

• Record Type: Journal Article
• Authors: Pires, Roberto P.S.; Guimarães, Jonas T.; Barros, Cássia P.; Balthazar, Celso F.; Chincha, Alexandra I.A.; Freitas, Mônica Q.; Duarte, Maria Carmela K.H.; Silva, Paulo H.F.; Pimentel, Tatiana C.; Abud, Yuri K.D.; Sant'Anna, Celso; Sant'Ana, Anderson S.; Silva, Marcia C.; Nascimento, Janaina S.; Cruz, Adriano G.
• Is Part Of: Food microbiology. Volume 97(2021)
• Publication Date: 2021-08
• Subjects: Ohmic heating -- Salmonella -- Weibull model -- Flow cytometry -- Scanning electron microscopy -- Infant formula; Food Microbiology -- Periodicals; Aliments -- Microbiologie -- Périodiques; Food -- Microbiology; Periodicals; Food -- Microbiology -- Periodicals; Food contamination -- Periodicals; 664.001579
• DOI: 10.1016/j.fm.2021.103737
• Languages: English
• ISSNs: 0740-0020

Abstract

Abstract: The effect of ohmic heating (OH) (50, 55, and 60 °C, 6 V/cm) on the inactivation kinetics (Weibull model) and morphological changes (scanning electron microscopy and flow cytometry) of Salmonella spp. in infant formula (IF) was evaluated. In addition, thermal load indicators (hydroxymethylfurfural and whey protein nitrogen index, HMF, and WPNI) and bioactive compounds (DPPH, total phenolics, ACE, α-amylase, and α-glucosidase inhibitory activities) were also studied. OH presented a more intense inactivation rate than conventional heating, resulting in a reduction of about 5 log CFU per mL at 60 °C in only 2.91 min, being also noted a greater cell membrane deformation, higher formation of bioactive compounds, and lower values for the thermal load parameters. Overall, OH contributed to retaining the nutritional value and improve food safety in IF processing. Highlights: Inactivation kinetics and morphological changes of Salmonella spp. in infant formula submitted to ohmic heating. Intense decay of microorganism counts and greater cell membrane deformation. Increased formation of bioactive compounds.