EVALUATION OF THE MICROBIAL INHIBITORY/CIDAL ACTIVITY OF THE CITREX®

MOLECULE IN:

FOODSHAROLD EDUARDO DURANGO G.Medical Mycology BacteriologistProfessor of Microbiology and Parasitology.Faculty of Medicine, U. of A.

JOSE IGNACIO BARGUIL P.Food Microbiology Bacteriologist.Technical Consultant in Food Protection.Consultant for Banco Interamericano de Desarrollo, BID.Technical Director, Continua Consultores.

Pediatric Infectology Research Laboratory, H.U.S.V.P

• Selection of sampling sites:

Vegetables for this study were purchased in a typical retail market in Medellín city, Colombia (Plaza Minorista).

METHODODLOGY

• Samples: 6 vegetable types from the above-mentioned market were analyzed in August 2003..

• Three (3) samples of the following vegetables were analyzed: cabbage (Brassica oleracea), tomatoes (Lycopersicon esculentum), lettuce (Latuca sativa), cucumbers (Cucumis sativus), cilantro leafs and roots (Coleandrum sativum) and junca onions.(Coleandrum sativum) y Cebolla Junca.

• Fifty to eighty (50-80) gram samples were washed following the Speck's (1984) technique. Samples were analyzed prior to and after a 30-minute disinfection with 400 ppm Citrex®.

Citrex Dilution

Vegetable Washing

CULTURE

MICROBIOLOGICAL METHOD

• Microbiological analysis: After washing (Speck, 1984) with one volume of sterile saline (0.85% NaCl) equivalent to 2X the weight of each vegetable sample, a 20-ml aliquot was obtained for total microorganism determination (escort microflora) using the plate count technique. Total coliforms and Escherichia coli were determined following the most probable number (MPN) technique (Speck,1984.) .

REFERENCE VALUE

Vegetable Sanitary Scoring: Based on International Commission for Food Microbiological Specifications (ICFMS) (Anonymous publication, 1974) criteria, two sanitary quality categories were established:

1. Acceptable (adequate for human consumption), total coliform and E. coli levels <103/g,

2.- Non acceptable (not adequate for human consumption), total coliform and E. coli levels >103/g.

VEGETABLE

AVGERAGE MESOPHYLLIC

ORGANISMSCOLIFOMS E. coli

Lettuce 106 - 108 104 – 105 104 – 105

Cabbage

103 – 10 4 102 - 103 101-103

Cilantro 106 – 10 8 105 – 106 104 - 106

JuncaOnions

106 – 10 8 104 – 105 104 – 105

Tomato 103 102-103 102

Cucumber 104 102-103 103

VEGETABLE

AVGERAGE MESOPHYLLIC

ORGANISMS

COLIFOMS/100ml

E. coli/100ml

Lettuce 103 – 105 102 – 103 101 – 102

Cabbage 101 – 10 3 101 101-102

Cilantro 103 – 10 5 102 – 104 102 – 103

JuncaOnions

104 – 10 5 102 – 103 102 – 103

Tomato 101- 103 100-101 0

Cucumber 102 101 0

Vegetables prior to and after treatment with 400 ppm Citrex®