title: Effects of UV irradiation in a continuous turbulent flow UV reactor on microbiological and sensory characteristics of cow's milk.
abstract: The dairy industry under current pasteurization conditions (15 s at 72°C) and sanitary standards achieves a safe product with excellent quality. In an ever-competitive market there is still a need to improve product quality and extend shelf life of dairy products to increase competitiveness  and open up new markets. In an attempt to test the effect of UV irradiation on microbiota of fluid milk, a continuous flow UV system at 254 nm was used to treat 3.5 and 2% fat milk at two UV doses (880 and 1,760 J liter(-1)). Milk was obtained from three processors, and two  lots from each processor were assessed. To assess the impact on the most descriptive native microbiota in pasteurized milk after UV illumination, the product was held at two storage temperatures (4 and 7°C) and tested weekly for 5 weeks for aerobic plate counts (psychrotrophic and mesophilic  bacteria), laboratory pasteurization counts, aerobic sporeformers, coliform organisms, and titratable acidity. Microbial counts for all tested microorganisms were lower in UV-treated milk when compared with control throughout storage at 4 and 7°C in both 3.5 and 2% fat milk. Sensory analysis  indicated that there is a sensory defect associated with UV treatment at the wavelength used.
authors.affiliation: Veterinary Medicine Teaching and Research Center, School of Veterinary Medicine, University of California at Davis, Tulare, CA 93274, USA.
authors.forename: P V
authors.initials: PV
authors.lastname: Rossitto
authors.forename: J S
authors.initials: JS
authors.lastname: Cullor
authors.forename: J
authors.initials: J
authors.lastname: Crook
authors.forename: J
authors.initials: J
authors.lastname: Parko
authors.forename: P
authors.initials: P
authors.lastname: Sechi
authors.forename: B T
authors.initials: BT
authors.lastname: Cenci-Goga
mesh_terms: D000818:Animals; D001419:Bacteria / Q000254:growth & development* / Q000302:isolation & purification; D002417:Cattle; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004307:Dose-Response Relationship, Radiation; D005506:Food Contamination / Q000032:analysis / Q000517:prevention & control*; D005514:Food Irradiation; D005516:Food Microbiology; D006801:Humans; D008892:Milk / Q000382:microbiology / Q000528:radiation effects / Q000592:standards; D013649:Taste; D013696:Temperature; D013997:Time Factors; D014466:Ultraviolet Rays