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.

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.

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 &gt; 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.

scholarly journals Identification of Genes Induced in Listeria monocytogenes during Growth and Attachment to Cut Cabbage, Using Differential Display

2005 ◽  
Vol 71 (9) ◽  
pp. 5236-5243 ◽  
Author(s):  
Jeffrey D. Palumbo ◽  
Aya Kaneko ◽  
Kimanh D. Nguyen ◽  
Lisa Gorski
Keyword(s):  
Gene Expression ◽  
Listeria Monocytogenes ◽  
Differential Display ◽  
Fresh Produce ◽  
Regulatory Protein ◽  
Nucleic Acid Metabolism ◽  
Isolation And Identification ◽  
Arbitrary Primers ◽  
Fresh Cut ◽  
The Impact

ABSTRACT The food-borne pathogen Listeria monocytogenes is a ubiquitous soil bacterium with the potential to contaminate fresh produce during cultivation and postharvest processing. In order to identify potential mechanisms by which L. monocytogenes may successfully attach to and colonize fresh produce, gene expression in L. monocytogenes cells inoculated onto fresh-cut cabbage was compared to gene expression in cells grown under control conditions. Differential display of reverse transcriptase PCR fragments amplified with a set of 81 arbitrary primers allowed the isolation and identification of 32 L. monocytogenes gene fragments that were observed to be more highly expressed under cabbage-associated conditions. Genes involved in carbohydrate, amino acid, and nucleic acid metabolism, motility and cell division, and transport were identified, as were a number of open reading frames (ORFs) encoding putative proteins with no known functions. Site-directed mutations in two ORFs encoding potential cell surface-associated proteins and a third ORF encoding a putative regulatory protein had no effect on the mutants' capacity to attach to fresh-cut cabbage. Although this study did not show clearly the impact of the differentially expressed genes on growth on cabbage, it is a first step in identifying some of the genetic factors that are potentially involved.

scholarly journals Impact of comorbidities on clinical prognosis in 1280 patients with different types of COVID-19

2020 ◽  
Vol 69 (1) ◽  
pp. 75-85
Author(s):  
Huilin Fang ◽  
Qiaomei Liu ◽  
Maomao Xi ◽  
Di Xiong ◽  
Jing He ◽  
...  
Keyword(s):  
Mortality Rate ◽  
Prolonged Treatment ◽  
Cure Rate ◽  
Clinical Prognosis ◽  
Risk Of Death ◽  
Increased Risk ◽  
Different Types ◽  
Patients With Diabetes ◽  
Critical Patients ◽  
The Impact

The study aimed to compare the clinical characteristics and outcomes of patients with different types (ordinary, severe, and critical) of COVID-19. A total of 1280 patients diagnosed with COVID-19 were retrospectively studied, including 793 ordinary patients, 363 severe patients and 124 critical patients. The impact of comorbidities on prognosis in ordinary, severe, and critical patients were compared and analyzed. The most common comorbidities were hypertension (33.0%), followed by diabetes (14.4%). The length of hospital stay and time from the onset to discharge were significantly longer in ordinary patients with comorbidities compared with those without comorbidities. Critical patients with comorbidities had significantly lower cure rate (19.3% vs 38.9%, p<0.05) and significantly higher mortality rate (53.4% vs 33.3%, p<0.05) compared with those without comorbidities. The time from onset to discharge was significantly longer in ordinary patients with hypertension compared with those without hypertension. The mortality rate of critical patients with diabetes was higher than that of patients without diabetes (71.4% vs 42.7%, p<0.05). Men had a significantly increased risk of death than women (OR=4.395, 95% CI 1.896 to 10.185, p<0.05); patients with diabetes had higher risk of death (OR=3.542, 95% CI 1.167 to 10.750, p<0.05). Comorbidities prolonged treatment time in ordinary patients, increased the mortality rate and reduced the cure rate of critical patients; hypertension and diabetes may be important factors affecting the clinical course and prognosis of ordinary and critical patients, respectively.

Foodborne Disease in Canada - a 10-year Summary from 1975 to 1984

1992 ◽  
Vol 55 (2) ◽  
pp. 123-132 ◽  
Author(s):  
EWEN C. D. TODD
Keyword(s):  
Staphylococcus Aureus ◽  
Listeria Monocytogenes ◽  
Clostridium Perfringens ◽  
Food Processing ◽  
Clostridium Botulinum ◽  
Foodborne Illness ◽  
Foodborne Disease ◽  
Naturally Occurring ◽  
Etiologic Agents ◽  
The Impact

Ten years of foodborne disease data from 1975 to 1984 in Canada were examined. Microorganisms, particularly Salmonella, Staphylococcus aureus, Clostridium perfringens and Bacillus cereus, were the main etiologic agents, but diseases also resulted from contamination of food with chemicals and parasites or food containing naturally occurring plant and animal toxins. An average of 5.6 deaths per year was recorded, with Salmonella, Clostridium botulinum, and Listeria monocytogenes responsible for most of them. The foods involved was, in general, potentially hazardous items, such as meat and poultry. Where information is known, most of the problems associated with foodborne illness occurred at foodservice establishments, but the impact of mishandling in homes and food processing establishments was also great. Incidents of microbiological etiology tended to peak in the summer months, particularly those caused by Salmonella, S. aureus, Campylobacter, and B. cereus.

Quota Women Are Threatening to Men

2017 ◽  
Vol 76 (3) ◽  
pp. 107-116 ◽  
Author(s):  
Klea Faniko ◽  
Till Burckhardt ◽  
Oriane Sarrasin ◽  
Fabio Lorenzi-Cioldi ◽  
Siri Øyslebø Sørensen ◽  
...  
Keyword(s):  
Decision Making ◽  
Organizational Performance ◽  
Gender Stereotypes ◽  
Perceived Threat ◽  
Preferential Treatment ◽  
Public Sector Employees ◽  
Different Types ◽  
Low Levels ◽  
Women In Decision Making ◽  
The Impact

Abstract. Two studies carried out among Albanian public-sector employees examined the impact of different types of affirmative action policies (AAPs) on (counter)stereotypical perceptions of women in decision-making positions. Study 1 (N = 178) revealed that participants – especially women – perceived women in decision-making positions as more masculine (i.e., agentic) than feminine (i.e., communal). Study 2 (N = 239) showed that different types of AA had different effects on the attribution of gender stereotypes to AAP beneficiaries: Women benefiting from a quota policy were perceived as being more communal than agentic, while those benefiting from weak preferential treatment were perceived as being more agentic than communal. Furthermore, we examined how the belief that AAPs threaten men’s access to decision-making positions influenced the attribution of these traits to AAP beneficiaries. The results showed that men who reported high levels of perceived threat, as compared to men who reported low levels of perceived threat, attributed more communal than agentic traits to the beneficiaries of quotas. These findings suggest that AAPs may have created a backlash against its beneficiaries by emphasizing gender-stereotypical or counterstereotypical traits. Thus, the framing of AAPs, for instance, as a matter of enhancing organizational performance, in the process of policy making and implementation, may be a crucial tool to countering potential backlash.

Measuring Effectiveness Of Economic Growth On Reducing Infant Mortality Rate In Tamilnadu

2019 ◽  
Vol 118 (4) ◽  
pp. 129-141
Author(s):  
Mr. Y. EBENEZER
Keyword(s):  
Economic Growth ◽  
Mortality Rate ◽  
Infant Mortality ◽  
Negative Relationship ◽  
Infant Mortality Rate ◽  
Domestic Product ◽  
Per Capita ◽  
The Impact ◽  
Adf Test ◽  
Bound Test

                   This paper deals with economic growth and infant mortality rate in Tamilnadu. The objects of this paper are to test the relationship between Per capita Net State Domestic Product and infant mortality rate and also to measure the impact of Per capita Net State Domestic Product on infant mortality rate in Tamil Nadu. This analysis has employed the ADF test and ARDL approach. The result of the study shows that IMR got reduced and Per capita Net State Domestic Product increased during the study period. This analysis also revealed that there is a negative relationship between IMR and the economic growth of Tamilnadu. In addition, ARDL bound test result has concluded that per capita Net State Domestic Product of Tamilnadu has long run association with IMR.

Situational Breakdowns

2019 ◽  
Author(s):  
Anne Nassauer
Keyword(s):  
United States ◽  
Large Scale ◽  
Contextual Factors ◽  
The United States ◽  
Social Outcomes ◽  
Dynamic Processes ◽  
Collective Decisions ◽  
Different Types ◽  
The Impact

This book provides an account of how and why routine interactions break down and how such situational breakdowns lead to protest violence and other types of surprising social outcomes. It takes a close-up look at the dynamic processes of how situations unfold and compares their role to that of motivations, strategies, and other contextual factors. The book discusses factors that can draw us into violent situations and describes how and why we make uncommon individual and collective decisions. Covering different types of surprise outcomes from protest marches and uprisings turning violent to robbers failing to rob a store at gunpoint, it shows how unfolding situations can override our motivations and strategies and how emotions and culture, as well as rational thinking, still play a part in these events. The first chapters study protest violence in Germany and the United States from 1960 until 2010, taking a detailed look at what happens between the start of a protest and the eruption of violence or its peaceful conclusion. They compare the impact of such dynamics to the role of police strategies and culture, protesters’ claims and violent motivations, the black bloc and agents provocateurs. The analysis shows how violence is triggered, what determines its intensity, and which measures can avoid its outbreak. The book explores whether we find similar situational patterns leading to surprising outcomes in other types of small- and large-scale events: uprisings turning violent, such as Ferguson in 2014 and Baltimore in 2015, and failed armed store robberies.

scholarly journals A global analysis of the impact of COVID-19 stay-at-home restrictions on crime

2021 ◽  
Author(s):  
Amy E. Nivette ◽  
Renee Zahnow ◽  
Raul Aguilar ◽  
Andri Ahven ◽  
Shai Amram ◽  
...  
Keyword(s):  
Public Space ◽  
Global Analysis ◽  
Sudden Change ◽  
Interrupted Time Series ◽  
Urban Crime ◽  
Substantial Variation ◽  
Different Types ◽  
Time Series Analyses ◽  
The Impact ◽  
At Home

AbstractThe stay-at-home restrictions to control the spread of COVID-19 led to unparalleled sudden change in daily life, but it is unclear how they affected urban crime globally. We collected data on daily counts of crime in 27 cities across 23 countries in the Americas, Europe, the Middle East and Asia. We conducted interrupted time series analyses to assess the impact of stay-at-home restrictions on different types of crime in each city. Our findings show that the stay-at-home policies were associated with a considerable drop in urban crime, but with substantial variation across cities and types of crime. Meta-regression results showed that more stringent restrictions over movement in public space were predictive of larger declines in crime.

Comprehensive Effects of Short-Term Rental Platforms Across Hotel Types in U.S. and International Destinations

2021 ◽  
pp. 193896552110335
Author(s):  
John W. O’Neill ◽  
Jihwan Yeon
Keyword(s):  
Service Providers ◽  
Comprehensive Analysis ◽  
Competitive Market ◽  
Substitution Effects ◽  
Short Term ◽  
Hotel Performance ◽  
The World ◽  
Different Types ◽  
Location Type ◽  
The Impact

In recent years, short-term rental platforms in the lodging sector, including Airbnb, VRBO, and HomeAway, have received extensive attention and emerged as potentially alternative suppliers of services traditionally provided by established commercial accommodation providers, that is, hotels. Short-term rentals have dramatically increased the available supply of rooms for visitors to multiple international destinations, potentially siphoning demand away from hotels to short-term rental businesses. In a competitive market, an increase in supply with constant demand would negatively influence incumbent service providers. In this article, we examine the substitution effects of short-term rental supply on hotel performance in different cities around the world. Specifically, we comprehensively investigate the substitution effects of short-term rental supply on hotel performance based on hotel class, location type, and region. Furthermore, we segment the short-term rental supply based on its types of accommodations, that is, shared rooms, private rooms, and entire homes, and both examine and quantify the differential effects of these types of short-term rentals on different types of hotels. This study offers a comprehensive analysis regarding the impact of multiple short-term rental platforms on hotel performance and offers both conceptual and practical insights regarding the nature and extent of the effects that were identified.

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