Sodium-benzoate and citrus extract increase the effect of homogenization towards spores of Fusarium oxysporum in pineapple juice

This paper reports on a combined approach (homogenization-HPH, sodium-benzoate and citrus extract) to inactivate spores of Fusarium oxysporum in pineapple juice. In 1st step HPH and antimicrobials were applied as single hurdles. Homogenization alone reduced spores at the undetectable level only through a 3-step treatment at 120/150 MPa; treatments at 1 or 2 steps reduced F. oxysporum spores by 1 and 2 log cfu/mL, respectively. Concerning the effectiveness of the antimicrobials, NIC (not-inhibitory concentration) and MIC values (minimal inhibitory concentration) of Na-benzoate and citrus extract were 181/289 mg/L and 1450/3700 mg/L, respectively. In the last step of the research benzoate (0-100 mg/L) and citrus extract (0-2000 mg/L) were combined through a two variables-five levels CCD (central composite design) and used in combination with a single step HPH treatment at 120 or 150 MPa. The use of Na-benzoate and citrus extract strengthened the effect of homogenization in pineapple juice and reduced spores of E oxysporum below the detection limit immediately after homogenization. (c) 2012 Elsevier Ltd. All rights reserved.