title: Addition of fumaric acid and sodium benzoate as an alternative method to achieve a 5-log reduction of Escherichia coli O157:H7 populations in apple cider.
abstract: A study was conducted to develop a preservative treatment capable of the Food and Drug Administration-mandated 5-log reduction of Escherichia coli O157:H7 populations in apple cider. Unpreserved apple cider was treated with generally recognized as safe acidulants and preservatives before inoculation with E. coli O157:H7 in test tubes and subjected to mild heat treatments (25, 35, and 45 degrees C) followed by refrigerated storage (4 degrees C). Fumaric acid had significant (P < 0.05) bactericidal effect when added to cider at 0.10% (wt/vol) and adjusted to pH 3.3, but citric and malic acid had no effect. Strong linear correlation (R2 = 0.96) between increasing undissociated fumaric acid concentrations and increasing log reductions of E. coli O157:H7 in apple cider indicated the undissociated acid to be the bactericidal form. The treatment that achieved the 5-log reduction in three commercial ciders was the addition of fumaric acid (0.15%, wt/vol) and sodium benzoate (0.05%, wt/vol) followed by holding at 25 degrees C for 6 h before 24 h of refrigeration at 4 degrees C. Subsequent experiments revealed that the same preservatives added to cider in flasks resulted in a more than 5-log reduction in less than 5 and 2 h when held at 25 and 35 degrees C, respectively. The treatment also significantly (P < 0.05) reduced total aerobic counts in commercial ciders to populations less than those of pasteurized and raw ciders from the same source (after 5 and 21 days of refrigerated storage at 4 degrees C, respectively). Sensory evaluation of the same ciders revealed that consumers found the preservative-treated cider to be acceptable.
authors.affiliation: Department of Food Science, The Pennsylvania State University, University Park, 16802, USA.
authors.forename: Justin E
authors.initials: JE
authors.lastname: Comes
authors.forename: Robert B
authors.initials: RB
authors.lastname: Beelman
mesh_terms: D016588:Anticarcinogenic Agents; D001628:Beverages / Q000382:microbiology*; D015169:Colony Count, Microbial; D019453:Escherichia coli O157 / Q000187:drug effects / Q000254:growth & development*; D005511:Food Handling / Q000379:methods; D005519:Food Preservation / Q000379:methods*; D005520:Food Preservatives / Q000494:pharmacology*; D005650:Fumarates / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D027845:Malus / Q000382:microbiology*; D020160:Sodium Benzoate / Q000494:pharmacology; D013649:Taste; D013696:Temperature; D013997:Time Factors
chemical_list: D016588:Anticarcinogenic Agents; D005520:Food Preservatives; D005650:Fumarates; C032005:fumaric acid; D020160:Sodium Benzoate