Electro-activation of potassium acetate, potassium citrate and calcium lactate: impact on solution acidity, Redox potential, vibrational properties of Raman spectra and antibacterial activity onE. coliO157:H7 at ambient temperature.
OBJECTIVE
To study the electro-activation of potassium acetate, potassium citrate and calcium lactate aqueous solutions and to evaluate their antimicrobial effect againstE. coliO157:H7 at ambient temperature.


RESULTS
Potassium acetate, potassium citrate and calcium lactate aqueous solutions were electrically excited in the anodic compartment of a four sectional electro-activation reactor. Different properties of the electro-activated solutions were measured such as: solutions acidity (pH and titratable), Redox potential and vibrational properties by Raman spectroscopy. Moreover, the antimicrobial activity of these solutions was evaluated againstE. coliO157:H7. The results showed a pH decrease from 7.07 ± 0.08, 7.53 ± 0.12 and 6.18 ± 0.1 down to 2.82 ± 0.1, 2.13 ± 0.09 and 2.26 ± 0.15, after 180 min of electro-activation of potassium acetate, potassium citrate and calcium lactate solution, respectively. These solutions were characterized by high oxidative ORP of +1076 ± 12, +958 ± 11 and +820 ± 14 mV, respectively. Raman scattering analysis of anolytes showed stretching vibrations of the hydrogen bonds with the major changes within the region of 3410-3430 cm-1. These solutions were used againstE. coliO157:H7 and the results from antimicrobial assays showed high antibacterial effect with a population reduction of ≥6 log CFU/ml within 5 min of treatment.


CONCLUSIONS
This study demonstrated the effectiveness of the electro-activation to confer to aqueous solutions of organic salts of highly reactive properties that differ them from their conjugated commercial acids. The electro-activated solutions demonstrated significant antimicrobial activity againstE. coliO157:H7.


CONCLUSIONS
This study opens new possibilities to use electro-activated solutions of salts of weak organic acids as food preservatives to develop safe, nutritive and low heat processed foods.
Institute of Nutrition and Functional Foods (INAF), Université Laval, Quebec, QC G1V 0A6 Canada ; Department of Soil Sciences and Agri-Food Engineering, Université Laval, Quebec, QC G1V 0A6 Canada.
Viacheslav
V
Liato
Institute of Nutrition and Functional Foods (INAF), Université Laval, Quebec, QC G1V 0A6 Canada ; Department of Food Sciences, Université Laval, Quebec, QC G1V 0A6 Canada.
Steve
S
Labrie
Institute of Nutrition and Functional Foods (INAF), Université Laval, Quebec, QC G1V 0A6 Canada ; Department of Soil Sciences and Agri-Food Engineering, Université Laval, Quebec, QC G1V 0A6 Canada ; Laval University, 2425 Rue de l'Agriculture, Pavillon P. Comtois, Quebec, QC G1V 0A6 Canada.
Mohammed
M
Aïder
Acetate; Acidity; Citrate; E. coli O157:H7; Electro-activation; Lactate; ORP; Raman