Survival and Growth of Foodborne Pathogens on Commercial Dishsponges/cloths and Inhibitory Effects of Sanitizers

Liquid smoke extracts have traditionally been used as flavoring agents, are known to possess antioxidant properties, and serve as natural alternatives to conventional antimicrobials. The antimicrobial efficacies of commercial liquid smoke samples may vary depending on their source and composition and the methods used to extract and concentrate the smoke. We investigated the MICs of eight commercial liquid smoke samples against Salmonella Enteritidis, Staphylococcus aureus, and Escherichia coli. The commercial liquid smoke samples purchased were supplied by the manufacturer as water-based or concentrated extracts of smoke from different wood sources. The MICs of the commercial smokes to inhibit the growth of foodborne pathogens ranged from 0.5 to 6.0% for E. coli, 0.5 to 8.0% for Salmonella, and 0.38 to 6% for S. aureus. The MIC for each liquid smoke sample was similar in its effect on both E. coli and Salmonella. Solvent-extracted antimicrobials prepared using pecan shells displayed significant differences between their inhibitory concentrations depending on the type of solvent used for extraction. The results indicated that the liquid smoke samples tested in this study could serve as effective natural antimicrobials and that their inhibitory effects depended more on the solvents used for extraction than the wood source.

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Inhibitory Effect of Commercial Green Tea and Rosemary Leaf Powders on the Growth of Foodborne Pathogens in Laboratory Media and Oriental-Style Rice Cakes

Journal of Food Protection ◽

10.4315/0362-028x-72.5.1107 ◽

2009 ◽

Vol 72 (5) ◽

pp. 1107-1111 ◽

Cited By ~ 19

Author(s):

SUN-YOUNG LEE ◽

SO-YOUNG GWON ◽

SEUNG-JU KIM ◽

BO KYUNG MOON

Keyword(s):

Green Tea ◽

Foodborne Pathogens ◽

Antimicrobial Activities ◽

Inhibitory Effect ◽

Enterobacter Sakazakii ◽

Inhibitory Effects ◽

Plant Materials ◽

Rice Cake ◽

Rice Cakes

The antimicrobial effects of green tea and rosemary added to foods as antagonists to foodborne pathogens were determined in laboratory media and oriental-style rice cakes. The growth of each pathogen (Bacillus cereus, Salmonella, Typhimurium, Enterobacter sakazakii, Escherichia coli O157:H7, Staphylococcus aureus, and Listeria monocytogenes) in tryptic soy broth or rice cake with or without addition of green tea or rosemary leaf powders before autoclaving or cooking, respectively, was investigated after inoculation. The addition of 1% green tea or rosemary produced similar results for inhibiting the growth of pathogens in tryptic soy broth. However, green tea was more effective than rosemary for inhibiting the growth of L. monocytogenes. Both botanicals had inhibitory effects against all pathogens tested in this study. Green tea was particularly effective against B. cereus, S. aureus, and L. monocytogenes, and rosemary was strongly inhibitory against B. cereus and S. aureus. The addition of 1 or 3% green tea or rosemary to rice cakes did not significantly reduce total aerobic counts; however, levels of B. cereus and S. aureus were significantly reduced in rice cakes stored for 3 days at room temperature (22°C). The order of antimicrobial activities against B. cereus in rice cake was 1% rosemary < 1% green tea < 3% rosemary = 3% green tea. These results indicate that the use of natural plant materials such as green tea and rosemary could improve the microbial quality of foods in addition to their functional properties.

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Application of nine air-driedCapsicum annumcultivars as food preservative: Micronutrient content, antioxidant activity, and foodborne pathogens inhibitory effects

International Journal of Food Properties ◽

10.1080/10942912.2016.1188310 ◽

2016 ◽

Vol 20 (4) ◽

pp. 899-910 ◽

Cited By ~ 2

Author(s):

Monica Rosa Loizzo ◽

Marco Bonesi ◽

Annalisa Serio ◽

Clemencia Chaves-López ◽

Tiziana Falco ◽

...

Keyword(s):

Antioxidant Activity ◽

Foodborne Pathogens ◽

Inhibitory Effects ◽

Food Preservative

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Inhibition of Listeria monocytogenes in pH-Adjusted Pasteurized Liquid Whole Egg†

Journal of Food Protection ◽

10.4315/0362-028x-66.6.999 ◽

2003 ◽

Vol 66 (6) ◽

pp. 999-1006 ◽

Cited By ~ 11

Author(s):

JAMES D. SCHUMAN ◽

BRIAN W. SHELDON

Keyword(s):

Thermal Inactivation ◽

The United States ◽

Inhibitory Effects ◽

Ph Values ◽

Liquid Model ◽

Order Of Magnitude ◽

Margin Of Safety ◽

Liquid Whole Egg ◽

Survival And Growth ◽

Whole Egg

Although the transmission of L. monocytogenes to humans via pasteurized egg products has not been documented, L. monocytogenes and other Listeria species have been isolated from commercially broken raw liquid whole egg (LWE) in both the United States and Ireland. Recent Listeria thermal inactivation studies indicate that conventional minimal egg pasteurization processes would effect only a 2.1- to 2.7-order-of-magnitude inactivation of L. monocytogenes in LWE; thus, the margin of safety provided by conventional pasteurization processes is substantially smaller for L. monocytogenes than for Salmonella species (a 9-order-of-magnitude process). The objective of this study was to evaluate the inhibitory effects of nisin on the survival and growth of L. monocytogenes in refrigerated and pH-adjusted (pH 6.6 versus pH 7.5) ultrapasteurized LWE and in a liquid model system. The addition of nisin (1,000 IU/ml) to pH-adjusted ultrapasteurized LWE reduced L. monocytogenes populations by 1.6 to >3.3 log CFU/ml and delayed (pH 7.5) or prevented (pH 6.6) the growth of the pathogen for 8 to 12 weeks at 4 and 10°C. Bioactive nisin was detected in LWE at both pH values for 12 weeks at 4°C. In subsequent experiments, Listeria reductions of >3.0 log CFU/ml were achieved within 24 h in both LWE and broth plus nisin (500 IU/ml) at pH 6.6 but not at pH 7.5, and antilisterial activity was enhanced when nisin was added as a solution rather than in dry form.

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Antimicrobial Effect of Guava Products against Foodborne Pathogens

HortScience ◽

10.21273/hortsci.39.4.778a ◽

2004 ◽

Vol 39 (4) ◽

pp. 778A-778

Author(s):

Guochen Yang* ◽

Salam A. Ibrahim ◽

Carl E. Niedziela

Keyword(s):

Foodborne Pathogens ◽

Block Design ◽

Foodborne Pathogen ◽

Water Extract ◽

Antimicrobial Effect ◽

Viable Cell ◽

Leaf Extracts ◽

E Coli ◽

Cell Counts ◽

Survival And Growth

This study investigated antimicrobial effects of guava products on the survival and growth of Escherichia coli O157:H7 in liquid medium. Seven strains of E. coli O157:H7 (944, 380, E0019, F4546, H1730, Cider, 9727) were tested. These strains were maintained in BHI broth. Guava fruits were sliced into small pieces and blended using a blender. Guava juice and leaves were then extracted using three solvents: water, methanol and hexane. Fruit extracts were dissolved in 10 ml BHI broth tubes to make a fruit solution of 5% (w/v). E. coli O157:H7 was inoculated into fruit solutions at 2 log cfu/mL. After incubation at 37 °C for 24 h, samples were serially diluted 10 folds. The proper diluent was spread-plated on TSA in duplicate. After incubation at 35 °C for 24 h, viable cell counts were obtained. The experiment was replicated three times in a randomized complete-block design. Results demonstrated that guava products (fruit, juice, and leaf extracts) significantly reduced survival and growth of the tested foodborne pathogen strains. Water extract showed the highest antimicrobial activity, followed by methanol and hexane. These results indicate guava extracts are a potential antimicrobial agent to ensure food safety.

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Inhibitory Effects of Combinations of Chemicals on Escherichia coli, Bacillus cereus, and Staphylococcus aureus Biofilms during the Clean-in-Place Process at an Experimental Dairy Plant

Journal of Food Protection ◽

10.4315/jfp-19-505 ◽

2020 ◽

Vol 83 (8) ◽

pp. 1302-1306

Author(s):

EUN-SEON LEE ◽

JONG-HUI KIM ◽

MI-HWA OH

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Citric Acid ◽

Bacillus Cereus ◽

Foodborne Pathogens ◽

Combined Treatment ◽

Food Additives ◽

Inhibitory Effects ◽

E Coli ◽

And Staphylococcus Aureus

ABSTRACT In dairy plants, clean-in-place (CIP) equipment cannot be disassembled, making it difficult to clean the inner surface of pipes. In this study, the inhibitory effects of chemical agents on biofilms formed by three foodborne pathogens, Bacillus cereus, Escherichia coli, and Staphylococcus aureus, was evaluated in a dairy CIP system. The experiment was conducted on a laboratory scale. Each of the three bacteria (200 μL) was inoculated onto stainless steel (SS) chips (25 by 25 mm), and the effect of single cleaning agents was evaluated. Individual treatments with NaClO (30, 50, 100, and 200 ppm), NaOH (0.005, 0.01, 0.05, and 0.1%), citric acid (1, 3, 5, and 7%), and nisin (5, 10, 25, 50, 100, and 200 ppm) were used to clean the SS chip for 10 min. The most effective concentration of each solution was selected for further testing in a commercial plant. Simultaneous cleaning with 200 ppm of NaClO (10 min) and 7% citric acid (10 min) reduced the biofilms of B. cereus, E. coli, and S. aureus by 6.9, 7.0, and 8.0 log CFU/cm2, respectively. Both 7% citric acid and 0.1% NaOH were optimal treatments for E. coli. NaClO and citric acid are approved for use as food additives in the Republic of Korea. Our results revealed that a combined treatment with NaClO and citric acid is the most effective approach for reducing biofilms formed by common foodborne pathogens on CIP equipment. These findings can contribute to the production of safe dairy products. HIGHLIGHTS

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Inhibitory effects of two types of food additives on biofilm formation by foodborne pathogens

MicrobiologyOpen ◽

10.1002/mbo3.853 ◽

2019 ◽

Vol 8 (9) ◽

Cited By ~ 9

Author(s):

Liyan Liu ◽

Congxiu Ye ◽

Thanapop Soteyome ◽

Xihong Zhao ◽

Jing Xia ◽

...

Keyword(s):

Foodborne Pathogens ◽

Biofilm Formation ◽

Food Additives ◽

Inhibitory Effects

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Proteolytic Fungi Isolated from Decayed and Damaged Raw Tomatoes and Implications Associated with Changes in Pericarp pH Favorable for Survival and Growth of Foodborne Pathogens

Journal of Food Protection ◽

10.4315/0362-028x-66.6.911 ◽

2003 ◽

Vol 66 (6) ◽

pp. 911-917 ◽

Cited By ~ 20

Author(s):

WENDY N. WADE ◽

LARRY R. BEUCHAT

Keyword(s):

Proteolytic Activity ◽

Foodborne Pathogens ◽

Pathogenic Bacteria ◽

Fruits And Vegetables ◽

Proteolytic Enzymes ◽

Fungal Growth ◽

Tomato Juice ◽

Pulp Tissue ◽

Survival And Growth ◽

Yeasts And Molds

Raw and minimally processed high-acid fruits and vegetables are considered to be at low or no risk for supporting growth of foodborne pathogens. The potential increase in the pH of tissues as a result of fungal growth, however, may enhance the potential for survival and growth. We examined 77 decayed and 138 damaged, raw, ripe tomatoes for the presence of yeasts and molds that produce proteolytic enzymes and other metabolites that can potentially increase the pH of pulp tissue. The pH of decayed and sound radial pericarp tissues (pulp) of decayed tomatoes ranged from 4.7 to 7.8 (mean = 6.2) and 4.3 to 5.8 (mean = 5.0), respectively, whereas the pH of damaged and sound pericarp of damaged tomatoes ranged from 4.2 to 7.8 (mean = 5.2) and 4.2 to 8.0 (mean = 4.9), respectively. The pH of sound pericarp of 8.5% of decayed tomatoes and 3.4% of damaged tomatoes, respectively, was >5.41. In contrast, the pH of 70% of the decayed tissue and 18% of the damaged tissue was >5.41. Fungal isolates (n = 371) recovered from decayed and damaged tomatoes on dichloran rose bengal chloramphenicol agar were examined for proteolytic activity on gelatin agar and standard methods caseinate agar. One hundred eight (29%) of the isolates exhibited proteolytic activity on one or both differential media; 96 (89%) were molds, and 12 (11%) were yeasts. The pH of both media increased at the edge of proteolytic fungal colonies. Growth of proteolytic isolates from decayed tomatoes on tomato juice agar (pH = 4.3) and on the surface of tomato juice (pH = 4.1) caused an increase in mean pH values at the colony/medium interface to 7.2 and 6.4, respectively. Results show that some fungi capable of infecting raw tomatoes, as well as the mycoflora incident on tomato surfaces, can increase the pH of pericarp and juice to levels favorable for growth of most foodborne pathogenic bacteria.

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Effect of Storage Temperature on Survival and Growth of Foodborne Pathogens on Whole, Damaged, and Internally Inoculated Jalapeños (Capsicum annuum var. annuum)

Journal of Food Protection ◽

10.4315/0362-028x.jfp-11-304 ◽

2012 ◽

Vol 75 (2) ◽

pp. 382-388 ◽

Cited By ~ 7

Author(s):

KARLEIGH HUFF ◽

RENEE BOYER ◽

CYNTHIA DENBOW ◽

SEAN O'KEEFE ◽

ROBERT WILLIAMS

Keyword(s):

Foodborne Pathogens ◽

Pathogenic Bacteria ◽

Storage Temperature ◽

External Surface ◽

Storage Conditions ◽

Internal Cavity ◽

Growth And Survival ◽

E Coli ◽

Foodborne Pathogenic Bacteria ◽

Survival And Growth

There is a lack of general knowledge regarding the behavior of foodborne pathogenic bacteria associated with jalapeño peppers. The survival and growth behaviors of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella enterica on the interior and exterior of jalapeño peppers were determined under different storage conditions. Jalapeños were inoculated with a five-strain cocktail of L. monocytogenes, E. coli O157:H7, or S. enterica on the intact external surface, injured external surface, or intact internal cavity of jalapeño peppers and held at 7 or 12°C for a period of 14 days. Populations of each pathogen were determined at 0, 1, 2, 5, 7 10, and 14 days throughout storage. The uninjured, intact external surface of jalapeño peppers did not support growth of the pathogens tested under both storage conditions, with the exception of L. monocytogenes at 12°C. Populations of E. coli and S. enterica declined on the external injured surface of peppers at 7°C, but populations of L. monocytogenes remained consistent throughout the length of storage. At 12°C, L. monocytogenes and S. enterica populations increased throughout storage, and E. coli populations remained unchanged on injured surfaces. The uninjured internal cavity of the jalapeño supported growth of all pathogens at 12°C. Overall, L. monocytogenes was the microorganism most capable of growth and survival in association with jalapeño peppers for the scenarios tested. Results emphasize the importance of jalapeño pepper quality and proper storage conditions in preventing or reducing pathogen survival and growth.

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