The antimicrobial potential of cauliflower, broccoli, and okara byproducts was assessed against Gram-positive and Gram-negative bacteria. Salmonella enterica serovar Typhimurium, Escherichia coli O157:H7, Bacillus cereus, and Listeria monocytogenes serovar 4b.
Growth behavior was assessed under exposure to 5% vegetable byproducts added to the reference medium, buffered peptone water (0.1% [wt/vol]), at 37°C. Although the byproducts were not effective against L. monocytogenes, they were bactericidal against Salmonella Typhimurium, E. coli O157:H7, and B. cereus. The most promising results were achieved with the cauliflower–Salmonella Typhimurium combination, because the bacterial population was reduced by 3.11 log10 cycles after 10 h of incubation at 37°C as a result of 5% cauliflower addition. Further studies were carried out for this combination, at different cauliflower concentrations (0, 0.5, 1, 5, 10, and 15%) and at temperatures in the range of 5–37°C. The greatest inactivation level (6.11 log10 cycles) was achieved at refrigeration temperature (5°C) using 15% cauliflower addition. Both temperature and cauliflower concentration significantly (p≤0.05) influenced the Salmonella Typhimurium inactivation level. The kinetic parameters were adjusted to mathematical models.
The modified Gompertz mathematical model provided an accurate fit (root-mean-square error (RMSE) [0.00009–0.21] and adjusted-R2 [0.81–0.99]) to experimental Salmonella Typhimurium survival curves describing inactivation kinetics of the pathogen to the antimicrobial effect of cauliflower byproduct.
Antimicrobial potential of cauliflower, broccoli, and okara byproducts against foodborne bacteria
Foodborne Pathogens and Disease. January 2015, 12(1): 39-46
Sanz-Puig Maria, Pina-Pérez Maria C., Criado Maria Nieves, Rodrigo Dolores, and Martínez-López Antonio