title: Effects of water, sodium hypochlorite, peroxyacetic acid, and acidified sodium chlorite on in-shell hazelnuts inoculated with Salmonella enterica serovar Panama.
abstract: Recent foodborne disease outbreaks involving minimally processed tree nuts have generated a need for improved sanitation procedures. Chemical sprays and dips have shown promise for reducing pathogens on fresh produce, but little research has been conducted for in-shell hazelnuts. This study analyzed the effectiveness of 3 chemical sanitizers for reducing Salmonella on in-shell hazelnuts. Treatments of water, sodium hypochlorite (NaOCl; 25 and 50 ppm), peroxyacetic acid (PAA; 80 and 120 ppm), and acidified sodium chlorite (ASC; 450, 830, and 1013 ppm) were sprayed onto hazelnut samples inoculated with Salmonella enterica serovar Panama. Hazelnut samples were immersed in liquid cultures of S. Panama for 24 h, air-dried, and then sprayed with water and chemical treatments. Inoculation achieved S. Panama populations of approximately 8.04 log CFU/hazelnut. Surviving S. panama populations were evaluated using a nonselective medium (tryptic soy agar), incubated 3 h, and then overlaid with selective media (xylose lysine deoxycholate agar). All of the chemical treatments significantly reduced S. Panama populations (P ≤ 0.0001). The most effective concentrations of ASC, PAA, and NaOCl treatments reduced populations by 2.65, 1.46, and 0.66 log units, respectively. ASC showed the greatest potential for use as a postharvest sanitation treatment.
authors.affiliation: Dept. of Food Science and Technology, Oregon State Univ., 100 Wiegand Hall, Corvallis, OR, 97331, U.S.A.
authors.forename: Lisa D
authors.initials: LD
authors.lastname: Weller
authors.forename: Mark A
authors.initials: MA
authors.lastname: Daeschel
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Durham
authors.forename: Michael T
authors.initials: MT
authors.lastname: Morrissey
mesh_terms: D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D031211:Corylus; D003362:Cost-Benefit Analysis; D005506:Food Contamination / Q000517:prevention & control*; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods; D005517:Foodborne Diseases / Q000517:prevention & control; D009754:Nuts / Q000737:chemistry / Q000382:microbiology*; D010463:Peracetic Acid / Q000032:analysis*; D019779:Salmonella enterica / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification; D012965:Sodium Chloride / Q000032:analysis; D012973:Sodium Hypochlorite / Q000032:analysis*; D014867:Water / Q000032:analysis
chemical_list: D014867:Water; D012965:Sodium Chloride; D012973:Sodium Hypochlorite; D010463:Peracetic Acid
keywords: Salmonella hazelnut; acidified sodium chlorite; peroxyacetic acid; sodium hypochlorite