title: Microbiological and sensory effects of the combined application of hot-cold organic acid sprays and steam condensation at subatmospheric pressure for decontamination of inoculated pig tissue surfaces.
abstract: We studied microbiological and sensory effects of treating pig tissue for 15 s with 55 and 10°C sprays of acetic acid (AA; 0.15 to 0.3 M) and lactic acid (LA; 0.1 to 0.2 M) solutions prior to the tissue being subjected to steam condensation (18 s at 65°C or 10 s at 75°C). LA or AA spraying and then steam treatment resulted in 3- to 4-log average reductions of Pseudomonas fragi and Yersinia enterocolitica inocula (6 to 7 log CFU/cm(2)), regardless of acid temperature or concentration. Buffered LA or 1:1 mixtures of AA:LA and then steam treatment yielded similar reductions. Most of the acid-steam-treated samples had microbial counts below the limit of detection (2 log CFU/cm(2)); thus, the results likely underestimate the potential of this procedure. When the period between inoculation and acid-steam treatment was extended from 0.5 to 24 h, up to a 1-log-higher microbial reduction was observed, due to a 1- to 2-log-greater initial contamination. Increasing the LA contact time to 6 min increased the microbial reduction by 0.8 log. Acid-steam treatment effected lower L* values (darker color) on pigskin, but higher L* values on muscle and fat tissue (paler color). Many muscle samples exhibited lower a* values and off-color brown hues. Off-odors were observed immediately after treatment, but with the exception of fat tissue and AA-treated samples, they largely disappeared during further storage. Off-flavors were only detected in AA-treated muscle samples.
authors.affiliation: Institute of Meat Hygiene, Meat Technology and Food Science, Department of Farm Animals and Veterinary Public Health, University of Veterinary Medicine-Vienna, Veterinärplatz 1, A-1210 Vienna, Austria.
authors.forename: Frans J M
authors.initials: FJ
authors.lastname: Smulders
authors.forename: Gabriele
authors.initials: G
authors.lastname: Wellm
authors.forename: Johann
authors.initials: J
authors.lastname: Hiesberger
authors.forename: Irene
authors.initials: I
authors.lastname: Rohrbacher
authors.forename: Alexandra
authors.initials: A
authors.lastname: Bauer
authors.forename: Peter
authors.initials: P
authors.lastname: Paulsen
mesh_terms: D000085:Acetates / Q000494:pharmacology; D000818:Animals; D001274:Atmospheric Pressure; D001419:Bacteria / Q000254:growth & development*; D003257:Consumer Product Safety; D004202:Disinfectants / Q000494:pharmacology*; D005506:Food Contamination / Q000032:analysis / Q000517:prevention & control; D005511:Food Handling / Q000379:methods*; D005519:Food Preservation / Q000379:methods*; D006801:Humans; D019344:Lactic Acid / Q000494:pharmacology; D008460:Meat / Q000382:microbiology* / Q000592:standards; D013227:Steam; D013552:Swine
chemical_list: D000085:Acetates; D004202:Disinfectants; D013227:Steam; D019344:Lactic Acid