Thermal and Chemical Treatments To Reduce Salmonella on Alfalfa ( Medicago sativa ) and Broccoli ( Brassica oleracea var. italica ) Seeds before and during the Sprouting Process: A Hurdle Approach

• Published in: Journal of food protection Vol. 83; no. 1; pp. 82 - 88
• Main Authors: Hinojosa-Dávalos, Joel, Arias-Rios, Elba Verónica, Varela-Hernández, Juan José, Cardona-López, Marco Antonio, Orozco-Muñiz, Ruben, Cabrera-Diaz, Elisa
• Format: Journal Article
• Language: English
• Published: United States Elsevier Limited 01.01.2020
• Subjects: Alfalfa; Brassica; Brassica - microbiology; Brassica oleracea; Broccoli; Caprylates; Chemical treatment; Colony Count, Microbial; E coli; Food Contamination - prevention & control; Food Microbiology; Food safety; Foodborne diseases; Germination; Heat; Heat treatment; Hot Temperature; Hydrogen Peroxide; Imbibition; Irrigation; Medicago sativa; Medicago sativa - microbiology; Octanoic acid; Organic chemistry; Pathogens; Polyethylene; Salmonella; Seeds; Seeds - microbiology; Stainless steel; Thermal shock; Vegetables; St Louis Missouri; United States > US; Alfalfa sprouts; Hurdle approach; Salmonella; Broccoli sprouts; Chemical treatment; Thermal treatment
• ISSN: 0362-028X; 1944-9097
• DOI: 10.4315/0362-028X.JFP-19-272

Sprouts are vehicles of foodborne diseases caused by pathogens such as . The aim of this study was to evaluate thermal and chemical treatments applied as a hurdle approach to reduce in alfalfa ( ) and broccoli ( var. ) seeds before and during their germination. Seeds, inoculated and then dried at 55°C for 48 h, were subjected to a chemical treatment and a thermal shock with (i) 75 mM caprylic acid at 70°C for 5 s, (ii) 0.04% CaO at 70°C for 5 s, or (iii) 1% H O at 70°C for 5 s. After each treatment, seeds were immersed in water at 3°C for 5 s. Next, the imbibition process was carried out with 0.016% H O at pH 3.0. Finally, the seeds were transferred to a rotary drum-type germinator and were sprayed with the same chemical solution that was applied before the imbibition process, for 20 s at intervals of 5 min for 40 min at 3 rpm. All chemical treatments reduced at least 5 log CFU/g on both seeds. Germination rates between 90 and 93% were obtained after application of thermal and chemical treatments. was not detected after the imbibition stage when caprylic acid and H O treatments were applied. However, during the germination process of both seeds, counts of >6 log CFU/g were obtained despite all treatments being applied at different stages of the sprouting process. These results demonstrated that thermal and chemical treatments used as a hurdle approach to control on alfalfa and broccoli seeds significantly reduced the pathogen concentration on seeds >5 log but were ineffective to eliminate and to control its growth during the sprouting process. The production of safe sprouts continues to be a major challenge for industry.