Antimicrobial efficacy of cinnamaldehyde, chitosan and high pressure processing against Cronobacter sakazakii in infant formula

This study investigated the antimicrobial efficacy of trans-cinnamaldehyde (TC) and chitosan (CH) along with high pressure processing (HPP) against Cronobacter sakazakii in infant formula. HPP, with or without TC, and CH, was applied to reconstituted powdered infant formula with C. sakazakii. Microbiological and sensory analyses, pH, protein oxidation, and emulsion stability of each sample were determined. C. sakazakii was totally inactivated by HPP (600 MPa for 5 min), TC (0.05%) and CH (1%) combination after 4, 6, and 2 weeks of storage at 7, 23, and 45°C, respectively. All HPP treatments exhibited a minimum of 5.5 log CFU/ml reduction while the highest reductions with non-HPP treatments were 2.1, 1.1, and 3.7 log CFU/ml at 7, 23, and 45°C storage, respectively. Although TC exhibited a cinnamon-like taste, overall sensory attributes were not significantly different from the control samples. Remarkable deformation and damage in C. sakazakii cells were observed by transmission electron microscopy after the application of HPP and bioactive compounds.