INTECIN   20395
INSTITUTO DE TECNOLOGIAS Y CIENCIAS DE LA INGENIERIA "HILARIO FERNANDEZ LONG"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Effectiveness of citric acid to reduce pathogen surrogates in spinach leaves.
Autor/es:
FINTEN, G.; JAGUS, R.J.; AGÜERO, M.V.; FERNANDEZ, M.V.
Lugar:
Cartagena
Reunión:
Simposio; VIII International Postharvest Symposium; 2016
Institución organizadora:
Universidad Politécnica de Cartagena
Resumen:
Fresh vegetables are considered an important source of foodborne pathogens when not properly managed from farm to fork. Washing and disinfection is a crucial step for reducing microorganisms of public health concern. Furthermore, the most spread disinfection agent, sodium hypochlorite (SH), is very criticized due to the formation of carcinogenic byproducts. Therefore the aim of this research is to test the effectiveness of citric acid (CA) at 0.5%, as an alternative to the traditional washing and disinfection of spinach, against surrogate markers at a high contamination load (≈10EXP8-9 cfu g-1) and a lower and more realistic one, ≈10EXP5-6 cfu g-1. Representing the typically found pathogens in leafy vegetables two strains of Escherichia coli (ATCC 3526 and 8739) and one of Listeria innocua (ATCC 33090) were evaluated through the plate count method. Briefly, discs of spinach were sampled in duplicate, dipped for 2.5 min in SH 200 ppm (1:40 w:v) to reduce native microbiota and dried with tissue paper. Next, samples were spot-inoculated simulating a postharvest contamination and incubated for 3 h at 22°C in order to allow bacterial attachment. And finally, dip washings following the same procedure described before were carried out with distilled water (DW), SH 200 ppm (pH 6.5-7.0), and CA 0.5%. The results indicate that the mechanical effect of DW was very little, being insignificant (p