title: Efficient reduction of pathogenic and spoilage microorganisms from apple cider by combining microfiltration with UV treatment.
abstract: Thermal pasteurization can achieve the U. S. Food and Drug Administration-required 5-log reduction of pathogenic Escherichia coli O157:H7 and Cryptosporidium parvum in apple juice and cider, but it can also negatively affect the nutritional and organoleptic properties of the treated products. In addition, thermal pasteurization is only marginally effective against the acidophilic, thermophilic, and spore-forming bacteria Alicyclobacillus spp., which is known to cause off-flavors in juice products. In this study, the efficiency of a combined microfiltration (MF) and UV process as a nonthermal treatment for the reduction of pathogenic and nonpathogenic E. coli, C. parvum, and Alicyclobacillus acidoterrestris from apple cider was investigated. MF was used to physically remove suspended solids and microorganisms from apple cider, thus enhancing the effectiveness of UV and allowing a lower UV dose to be used. MF, with ceramic membranes (pore sizes, 0.8 and 1.4 μm), was performed at a temperature of 10 °C and a transmembrane pressure of 155 kPa. The subsequent UV treatment was conducted using at a low UV dose of 1.75 mJ/cm(2). The combined MF and UV achieved more than a 5-log reduction of E. coli, C. parvum, and A. acidoterrestris. MF with the 0.8-μm pore size performed better than the 1.4-μm pore size on removal of E. coli and A. acidoterrestris. The developed nonthermal hurdle treatment has the potential to significantly reduce pathogens, as well as spores, yeasts, molds, and protozoa in apple cider, and thus help juice processors improve the safety and quality of their products.
authors.affiliation: Department of Food Science, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Dongjun
authors.initials: D
authors.lastname: Zhao
authors.affiliation: Department of Food Science, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Jessie Usaga
authors.initials: JU
authors.lastname: Barrientos
authors.affiliation: Department of Animal and Food Science, University of Delaware, Newark, Delaware 19716, USA.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Animal and Food Science, University of Delaware, Newark, Delaware 19716, USA.
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Markland
authors.affiliation: Department of Animal and Food Science, University of Delaware, Newark, Delaware 19716, USA.
authors.forename: John J
authors.initials: JJ
authors.lastname: Churey
authors.affiliation: Department of Food Science, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Olga I
authors.initials: OI
authors.lastname: Padilla-Zakour
authors.affiliation: Department of Food Science, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Randy W
authors.initials: RW
authors.lastname: Worobo
authors.affiliation: Department of Animal and Food Science, University of Delaware, Newark, Delaware 19716, USA.
authors.forename: Kalmia E
authors.initials: KE
authors.lastname: Kniel
authors.affiliation: Department of Food Science, Cornell University, Ithaca, New York 14853, USA. cim24@cornell.edu.
authors.forename: Carmen I
authors.initials: CI
authors.lastname: Moraru
mesh_terms: D056450:Alicyclobacillus / Q000302:isolation & purification* / Q000528:radiation effects; D001628:Beverages / Q000382:microbiology*; D055598:Chemical Phenomena; D015169:Colony Count, Microbial; D016785:Cryptosporidium parvum / Q000302:isolation & purification* / Q000528:radiation effects; D004269:DNA, Bacterial / Q000302:isolation & purification; D016054:DNA, Protozoan / Q000302:isolation & purification; D019453:Escherichia coli O157 / Q000302:isolation & purification* / Q000528:radiation effects; D005506:Food Contamination / Q000517:prevention & control*; D005516:Food Microbiology; D016266:Food Parasitology; D027845:Malus / Q000382:microbiology*; D061352:Pasteurization; D013696:Temperature; D014466:Ultraviolet Rays
chemical_list: D004269:DNA, Bacterial; D016054:DNA, Protozoan