title: Physicochemical and microbiological characteristics of beef treated with high-intensity ultrasound and stored at 4 °C.
abstract: BACKGROUND
  The application of high-intensity ultrasound causes changes in the physical and chemical properties of biological materials including meat. In this study the physicochemical and microbiological characteristics of beef after the application of high-intensity ultrasound for 60 and 90 min and subsequent storage at 4 °C for 0, 2, 4, 6, 8 and 10 days were evaluated.
  
  
  RESULTS
  The ultrasound-treated meat showed higher (P < 0.05) pH and luminosity than the control, with no difference (P > 0.05) between sonication times. The redness of ultrasound-treated meat was initially lower than that of control meat, but no difference (P > 0.05) was observed after day 8 of storage. The 90 min ultrasound-treated meat had higher (P < 0.05) yellowness during the entire storage period. Ultrasound decreased (P < 0.05) coliform, mesophilic and psychrophilic bacteria in the meat throughout the storage period; however, the original microbial loads increased constantly during refrigeration. The 90 min ultrasound-treated meat showed the greatest reduction in microbial load during storage. Coliforms and psychrophilic bacteria were the most affected by ultrasound.
  
  
  CONCLUSIONS
  The application of high-intensity ultrasound to beef semitendinosus muscle stored at 4 °C decreased bacterial growth without affecting the physicochemical quality of meat.
authors.affiliation: Facultad de Zootecnia y Ecología, Universidad Autónoma de Chihuahua, Perif. Fco. R. Almada km 1, Chihuahua, Chih 31453, Mexico.
authors.forename: Omaro
authors.initials: O
authors.lastname: Caraveo
authors.affiliation: Facultad de Zootecnia y Ecología, Universidad Autónoma de Chihuahua, Perif. Fco. R. Almada km 1, Chihuahua, Chih 31453, Mexico.
authors.forename: Alma D
authors.initials: AD
authors.lastname: Alarcon-Rojo
authors.affiliation: Facultad de Zootecnia y Ecología, Universidad Autónoma de Chihuahua, Perif. Fco. R. Almada km 1, Chihuahua, Chih 31453, Mexico.
authors.forename: Ana
authors.initials: A
authors.lastname: Renteria
authors.affiliation: Facultad de Zootecnia y Ecología, Universidad Autónoma de Chihuahua, Perif. Fco. R. Almada km 1, Chihuahua, Chih 31453, Mexico.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Santellano
authors.affiliation: Faculty of Health and Life Sciences, Coventry University, Priory Street, Coventry, UK.
authors.forename: Larysa
authors.initials: L
authors.lastname: Paniwnyk
mesh_terms: D000818:Animals; D002417:Cattle; D015169:Colony Count, Microbial; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D006090:Gram-Negative Bacteria / Q000302:isolation & purification*; D006094:Gram-Positive Bacteria / Q000302:isolation & purification*; D006801:Humans; D008460:Meat / Q000382:microbiology*; D014463:Ultrasonography
keywords: bacteria; beef; high-intensity ultrasound; physicochemical properties