Effect of alpha-cyclodextrin-cinnamic acid inclusion complexes on populations of Escherichia coli O157:H7 and Salmonella enterica in fruit juices.
Cinnamic acid (CA), a naturally occurring organic acid found in fruits and spices, has antimicrobial activity against spoilage and pathogenic bacteria, but low aqueous solubility limits its use. The purpose of this study was to determine the effectiveness of solubility-enhancing alpha-cyclodextrin-CA inclusion complexes against Escherichia coli O157:H7 and Salmonella enterica serovars suspended in apple cider or orange juice at two different incubation temperatures (4 and 26 degrees Celsius). Two concentrations (400 and 1,000 mg/liter) of alpha-cyclodextrin-CA inclusion complex were aseptically added to apple cider inoculated with E. coli O157:H7 (7 log CFU/ml) and orange juice inoculated with a cocktail of six Salmonella enterica serovars (7 log CFU/ml). Samples were extracted at 0 min, at 2 min, and at 24-h intervals for 7 days, serially diluted in 0.1 % peptone, spread plated in duplicate onto tryptic soy agar, and incubated at 35 degrees Celsius for 24 h. Populations of E. coli O157:H7 in apple cider were significantly reduced (P < or = 0.05) during the 7-day sampling period in all solutions regardless of temperature. Compared with the controls, populations were significantly reduced by the addition of 400 and 1,000 mg/liter inclusion complex, but reductions were not significantly different (P > or = 0.05) between the two treatment groups (400 and 1,000 mg/liter). Salmonella was significantly reduced in all solutions regardless of temperature. There were significant differences between the control and each inclusion complex concentration at 4 and 26 degrees Celsius. Coupled with additional processing steps, alpha-cyclodextrin-CA inclusion complexes may provide an alternative to traditional heat processes.
Truong
Vy T
VT
Department of Food Science and Technology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.
Boyer
Renee R
RR
McKinney
Julie M
JM
O'Keefe
Sean F
SF
Williams
Robert C
RC
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001628:Beverages / Q000032:analysis / Q000382:microbiology; D002934:Cinnamates / Q000494:pharmacology*; D032084:Citrus sinensis / Q000382:microbiology; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D019453:Escherichia coli O157 / Q000187:drug effects* / Q000254:growth & development; D005511:Food Handling / Q000379:methods; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods*; D005638:Fruit / Q000382:microbiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D027845:Malus / Q000382:microbiology; D019779:Salmonella enterica / Q000187:drug effects* / Q000254:growth & development; D013696:Temperature; D013997:Time Factors; D047391:alpha-Cyclodextrins / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D002934:Cinnamates; D047391:alpha-Cyclodextrins; C029010:cinnamic acid