Efficacy of Home Washing Methods in Controlling Surface Microbial Contamination on Fresh Produce

2006 ◽  
Vol 69 (2) ◽  
pp. 330-334 ◽  
Author(s):  
AGNES KILONZO-NTHENGE ◽  
FUR-CHI CHEN ◽  
SANDRIA L. GODWIN
Keyword(s):  
Bacterial Contamination ◽  
Microbial Contamination ◽  
Tap Water ◽  
Fresh Produce ◽  
Listeria Innocua ◽  
Home Setting ◽  
Paper Towel ◽  
Cleaning Procedures ◽  
Cleaning Methods ◽  
Water Rinse

Much effort has been focused on sanitation of fresh produce at the commercial level; however, few options are available to the consumer. The purpose of this study was to determine the efficacy of different cleaning methods in reducing bacterial contamination on fresh produce in a home setting. Lettuce, broccoli, apples, and tomatoes were inoculated with Listeria innocua and then subjected to combinations of the following cleaning procedures: (i) soak for 2 min in tap water, Veggie Wash solution, 5% vinegar solution, or 13% lemon solution and (ii) rinse under running tap water, rinse and rub under running tap water, brush under running tap water, or wipe with wet/dry paper towel. Presoaking in water before rinsing significantly reduced bacteria in apples, tomatoes, and lettuce, but not in broccoli. Wiping apples and tomatoes with wet or dry paper towel showed lower bacterial reductions compared with soaking and rinsing procedures. Blossom ends of apples were more contaminated than the surface after soaking and rinsing; similar results were observed between flower section and stem of broccoli. Reductions of L. innocua in both tomatoes and apples (2.01 to 2.89 log CFU/g) were more than in lettuce and broccoli (1.41 to 1.88 log CFU/g) when subjected to same washing procedures. Reductions of surface contamination of lettuce after soaking in lemon or vinegar solutions were not significantly different (P > 0.05) from lettuce soaking in cold tap water. Therefore, educators and extension workers might consider it appropriate to instruct consumers to rub or brush fresh produce under cold running tap water before consumption.

Kitchen-scale Treatments for Reduction of Listeria monocytogenes in Prepared Produce

2021 ◽  
Author(s):  
Carly Blair Gomez ◽  
Elliot T. Ryser ◽  
Bradley Marks
Keyword(s):  
Listeria Monocytogenes ◽  
Mortality Rate ◽  
Untreated Control ◽  
Tap Water ◽  
Fresh Produce ◽  
Foodborne Illness ◽  
Different Types ◽  
Low Incidence ◽  
The Impact ◽  
Water Rinse

Listeriosis, a foodborne illness caused by Listeria monocytogenes , has relatively low incidence, but a substantial mortality rate, particularly in immunocompromised populations. Because of the known risk of L. monocytogenes and other pathogens in produce, immunocompromised individuals are often placed on neutropenic diets that exclude fresh produce. Therefore, this study aimed to evaluate several kitchen-scale treatments as potential interventions to reduce L. monocytogenes in prepared produce. Cucumbers, apples, and celery were dip inoculated with a three-strain cocktail of L. monocytogenes and dried for 24 h. Inoculated products were subjected to the following treatments as applicable: commercial sanitizer soak (90 s, with agitation), tap water rinse (15 s), tap water soak (90 s, with agitation), surface blanching (25 s), tap water rinse (15 s) followed by peeling, and surface blanching (25 s) followed by peeling. Additionally, inoculum uptake in celery and the impact of two different types of peelers (mechanical crank and manual) were assessed. Treated samples were plated on differential media and incubated for 48 h at 37°C. L. monocytogenes populations were then enumerated and compared to the untreated control (log CFU/g). All treatments lacked efficacy for celery, with reductions significantly less ( P < 0.05) than in other products, likely due to inoculum internalization. The sanitizer soak, tap water rinse, and tap water soak did not differ in efficacy ( P > 0.05), which was low for cucumbers (< 1.5 log CFU/g), apples (< 1.3 log CFU/g), and celery (< 0.7 log CFU/g). The two types of apple peelers did not differ in efficacy ( P > 0.05). Surface blanching and surface blanching followed by peeling were the most effective treatments in both cucumbers and apples ( P < 0.05), with average reductions of 4.2 to 5.1 and 3.5 to 5.9 log CFU/g, respectively.

Assessment of Bacterial Contamination of Orthodontic Arch wire

2019 ◽  
Vol 31 (1) ◽  
pp. 48-51
Author(s):  
Suha S Hassan ◽  
Nidhal H. Ghaib ◽  
Batool H Al-Ghurabi
Keyword(s):  
Bacterial Contamination ◽  
Microbial Contamination ◽  
Ethylenediaminetetraacetic Acid ◽  
Bacterial Species ◽  
Brain Heart Infusion ◽  
Control Groups ◽  
Dental Practitioners ◽  
Significant Difference ◽  
Bacillus Spp ◽  
Droplet Transmission

Background: The microorganisms can impend the life of health care professional and particularly the dental practitioners. They can be transmitted by different ways like airborne and droplet transmission. The current study was carried out to identify whether the arch wires that received from the manufactures are free from microbial contamination and to determine the bacterial species attached to the arch wires. Materials and Methods: This study involved eighty samples, consisted of two types of arch wires (nitinol and stainless-steel) from four companies (3M, G&H, Jiscop, OrthoTechnology). These wires inserted in a plane tube that contains 10 -ml of (Tris [tris(hydroxymethyl)aminomethane] and EDTA (ethylenediaminetetraacetic acid) tris-EDTA and brain heart infusion (BHI) broth. A 0.1 ml was withdrawn from the tube and spread on agar plates. The control groups consist of 16 plane tube (8 tubes with tris-EDTA and other 8 tubes with (BHI). Results: Microbial sampling yielded growth from 5 of the 80 arch wires. The predominant bacteria that isolated were Bacillus spp. No growth was recovered from 75 of the samples and from controls. The bacteria were isolated by BHI reagent and no growth was observed by tris-EDTA reagent with statistically significant difference (P<0.05). The Bacillus spp. found only in the G&H and Jiscop companies, however, no statistically significant difference was found among them (P>0.05). With regard to the presence and distribution of bacteria according to the types of wires, the present results clarified that cases of contamination with Bacillus spp. were found in the nitinol arch wires with statistically significant difference (P<0.05). Conclusions: The results of the current study revealed low count of bacterial contamination in the two types of companies (G&H and Jiscop). Not all materials that received from the manufactures are free from contamination and an effective sterilization regimen is needed to avoid cross-contamination.

scholarly journals Postharvest Supply Chain with Microbial Travelers: a Farm-to-Retail Microbial Simulation and Visualization Framework

2018 ◽  
Vol 84 (17) ◽  
Author(s):  
Claire Zoellner ◽  
Mohammad Abdullah Al-Mamun ◽  
Yrjo Grohn ◽  
Peter Jackson ◽  
Randy Worobo
Keyword(s):  
Supply Chain ◽  
Foodborne Pathogens ◽  
Empirical Data ◽  
Microbial Growth ◽  
Microbial Contamination ◽  
Fresh Produce ◽  
The United States ◽  
Plate Count ◽  
Modeling Tool ◽  
Parameter Ranges

ABSTRACTFresh produce supply chains present variable and diverse conditions that are relevant to food quality and safety because they may favor microbial growth and survival following contamination. This study presents the development of a simulation and visualization framework to model microbial dynamics on fresh produce moving through postharvest supply chain processes. The postharvest supply chain with microbial travelers (PSCMT) tool provides a modular process modeling approach and graphical user interface to visualize microbial populations and evaluate practices specific to any fresh produce supply chain. The resulting modeling tool was validated with empirical data from an observed tomato supply chain from Mexico to the United States, including the packinghouse, distribution center, and supermarket locations, as an illustrative case study. Due to data limitations, a model-fitting exercise was conducted to demonstrate the calibration of model parameter ranges for microbial indicator populations, i.e., mesophilic aerobic microorganisms (quantified by aerobic plate count and here termed APC) and total coliforms (TC). Exploration and analysis of the parameter space refined appropriate parameter ranges and revealed influential parameters for supermarket indicator microorganism levels on tomatoes. Partial rank correlation coefficient analysis determined that APC levels in supermarkets were most influenced by removal due to spray water washing and microbial growth on the tomato surface at postharvest locations, while TC levels were most influenced by growth on the tomato surface at postharvest locations. Overall, this detailed mechanistic dynamic model of microbial behavior is a unique modeling tool that complements empirical data and visualizes how postharvest supply chain practices influence the fate of microbial contamination on fresh produce.IMPORTANCEPreventing the contamination of fresh produce with foodborne pathogens present in the environment during production and postharvest handling is an important food safety goal. Since studying foodborne pathogens in the environment is a complex and costly endeavor, computer simulation models can help to understand and visualize microorganism behavior resulting from supply chain activities. The postharvest supply chain with microbial travelers (PSCMT) model, presented here, provides a unique tool for postharvest supply chain simulations to evaluate microbial contamination. The tool was validated through modeling an observed tomato supply chain. Visualization of dynamic contamination levels from harvest to the supermarket and analysis of the model parameters highlighted critical points where intervention may prevent microbial levels sufficient to cause foodborne illness. The PSCMT model framework and simulation results support ongoing postharvest research and interventions to improve understanding and control of fresh produce contamination.

Household greywater use practices in Melbourne, Australia

2013 ◽  
Vol 13 (2) ◽  
pp. 294-301 ◽  
Author(s):  
M. Sinclair ◽  
J. O'Toole ◽  
M. Malawaraarachchi ◽  
K. Leder
Keyword(s):  
Urban Areas ◽  
Microbial Contamination ◽  
Tap Water ◽  
Severe Drought ◽  
Urban Water ◽  
Housing Developments ◽  
End Use ◽  
Volume Estimates ◽  
And Storage ◽  
Greywater Reuse

Research on the potential of greywater reuse to reduce urban tap water demand has focused mainly on permanently installed greywater treatment or irrigation systems. These may be readily implemented in new housing developments, but experience in Australia shows their uptake by established households in urban areas is low. The majority of households employ simple and temporary methods for greywater collection and use, but their behaviour has not been well documented. We characterised the greywater use practices of over 1,000 Melbourne households during a 5-year period (2007 to 2011) which included 3 years of severe drought with stringent restrictions on outdoor tap water use. Greywater was most frequently collected from the laundry and bathroom, and generally used within 24 hours. Garden watering was the most common end use, and treatment of greywater to reduce microbial contamination was very rare. Volume estimates by householders suggest that on average around 10% of tap water used in the home was being collected for reuse. When drought conditions and water restrictions eased, over 40% of user households discontinued greywater use. Widespread adoption of permanent greywater collection, treatment and storage systems by households would be required to achieve a lasting effect on urban water consumption.

Evaluation of Bacterial Contamination on Prehospital Ambulances Before and After Disinfection

2018 ◽  
Vol 33 (6) ◽  
pp. 602-606
Author(s):  
Roohollah Farhadloo ◽  
Jalil Goodarzi Far ◽  
Mohammad Reza Azadeh ◽  
Saeed Shams ◽  
Mohammad Parvaresh-Masoud
Keyword(s):  
Nosocomial Infections ◽  
Bacterial Contamination ◽  
Microbial Contamination ◽  
Contamination Level ◽  
Publication Type ◽  
Bacterial Agent ◽  
Before And After ◽  
Quasi Experimental ◽  
Effective Role ◽  
Major Factors

AbstractBackgroundThe contamination of the environment, ambulance equipment, and staff hands consequently are major factors which create nosocomial infections in emergency patients. The contamination of equipment and devices plays an important role in nosocomial infections.ObjectivesThe aim of this study was to determine the effectiveness of a disinfectant on the rate of microbial contamination of ambulances in Qom Emergency Medical Services (EMS), Qom, Iran.MethodsThis is a quasi-experimental study with a before-after design in order to determine microbial contaminations at the rear and front cabin of ambulances, as well as medical equipment being utilized in Qom EMS. Saya sept-HP-2% solution was used for disinfection. Bacteriological standard methods were used to identify the contaminations.ResultsThe contamination rates before and after use of disinfection solution were 52% and eight percent, respectively. Coagulase-negative staphylococci were the most commonly isolated bacterial agent from the equipment (53%). In all equipment, the contamination level has shown a significant reduction after applying disinfectant.Conclusions:In spite of the fact that the rate of infection from ambulance equipment is high, the results showed that the use of the suitable disinfectant had an effective role in the reduction of bacteria.FarhadlooR, Goodarzi FarJ, AzadehMR, ShamsS, Parvaresh-MasoudM.Evaluation of bacterial contamination on prehospital ambulances before and after disinfection. Prehosp Disaster Med. 2018;33(6):602–606.

Evaluation of biofilm-forming abilities of Listeria monocytogenes (ATCC 19115) and efficacy of different washing methods for removal of biofilm on apple

Food Research ◽  
2021 ◽  
Vol 5 (4) ◽  
pp. 259-265
Author(s):  
Y. Ali ◽  
H.Y. Mah ◽  
E.T. Phuah ◽  
S.N. Chen ◽  
S.K. Yeo ◽  
...  
Keyword(s):  
Supply Chain ◽  
Listeria Monocytogenes ◽  
Biofilm Formation ◽  
Time Course ◽  
Tap Water ◽  
Fresh Produce ◽  
Foodborne Illness ◽  
Food Supply Chain ◽  
Log Reduction ◽  
Crystal Violet Assay

Fresh produce can be contaminated at any stage along the food supply chain. In this study, apple was chosen to determine the time course of biofilm formation by Listeria monocytogenes (ATCC 19115), as well as to compare the efficacy of different household washing methods such as scrubbing with hands under running tap water, soaking with and without commercial vegetable wash with different treatment times in removing the biofilm formation by L. monocytogenes on apple surface. The biofilm formation was quantified using crystal violet assay and the result showed that L. monocytogenes took 18 hrs to form matured biofilm on apple surface. Besides, scrubbing apples with hands under running tap water for 30 s and 60 s were the most effective method which significantly removed (P<0.05) biofilm formed on the apple surface with approximately 5.93 log reduction. Soaking apples with vegetable wash for 5 mins and 10 mins were also found to be significantly effective (P<0.05) in reducing L. monocytogenes biofilm. Since L. monocytogenes can form matured biofilm on fresh produce, therefore efficient washing step is important before consuming fresh produce to lower the risk of foodborne illness.

Environmental Sources of Listeria and Yersinia in Vermont Dairy Plants

1991 ◽  
Vol 54 (8) ◽  
pp. 607-611 ◽  
Author(s):  
RONA B. KLAUSNER ◽  
CATHERINE W. DONNELLY
Keyword(s):  
Environmental Samples ◽  
Microbial Contamination ◽  
Listeria Innocua ◽  
Manufacturing Plants ◽  
Yersinia Species ◽  
Dairy Processing ◽  
Processing Plants ◽  
Contact Surfaces ◽  
Area Of Concern ◽  
Additional Area

This survey was conducted to identify specific environmental sources of Listeria and Yersinia in Vermont dairy plants, and to further determine whether the type of plant and specific conditions existing within plants influenced the incidence of positive microbiological results. A total of 361 environmental samples, focusing on floors and other nonproduct contact surfaces, was taken from all of Vermont's 34 dairy processing plants. The incidence of Listeria monocytogenes (1.4%) was low compared to the incidence of Listeria innocua (16.1%). While only 2.5% yielded other Yersinia species, 10.5 % of the sites were positive for Yersinia enterocolitica. Sites positive for either Listeria or Yersinia were statistically more likely to produce a positive result for both (P&lt;.05). Fluid plants had the highest incidence of both Listeria and Yersinia when compared to cheese plants or other types of dairy manufacturing plants. Areas associated with case washers in fluid plants had the highest incidence of microbial contamination. An additional area of concern for all types of plants was sanitizing floor mats and foot baths from which positive microbiological results were obtained. Contamination in wet areas was significantly greater than in dry areas of the plants (P&lt;.05). Identification of the sources and conditions associated with these problematic bacterial pathogens is an important step in learning to control their incidence in dairy processing environments.

Potential for Microbial Contamination of ADD-Vantage Admixtures

1992 ◽  
Vol 8 (5) ◽  
pp. 195-197
Author(s):  
Teresa J. Hudson ◽  
Ellen M. Ambroziak ◽  
Rebecca M.R. Coley
Keyword(s):  
Bacterial Contamination ◽  
Microbial Contamination ◽  
Data Extraction ◽  
Working Hours ◽  
Minimal Risk ◽  
Hospital Environments ◽  
Regular Work ◽  
Positive Results ◽  
Assembly Site

Objective: To test for potential bacterial contamination of the ADD-Vantage system when the components are assembled in various hospital environments. Study Design: One hundred fifty ADD-Vantage units were assembled by three different people in three separate locations within a hospital. Each person assembled ten units per day; the study spanned five days. After 72 hours of incubation, units were inspected for evidence of contamination. Setting: ADD-Vantage units were assembled by a pharmacist in a laminar-flow hood, a pharmacy student using the pharmacy counter, and a nurse at a patient's bedside table. Personnel at each site wore their regular work attire. Each person observed handwashing techniques normally used during routine working hours. Data Extraction: Positive results were sent to the hospital microbiology laboratory for determination of growth type. Results: After 72 hours, none of the systems exhibited microbial growth on visual inspection. No differences in microbial contamination of the ADD-Vantage systems relative to assembly site, day of assembly, or person performing the assembly were observed. The incidence of contamination was calculated at less than seven percent. Conclusions: There is minimal risk of bacterial contamination when ADD-Vantage systems are compounded either on a pharmacy counter or at a patient's bedside. Larger samples must be studied in order to detect differences in the incidence of contamination among assembly sites.

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