Research Publications (Food Safety)

Gaseous ozone treatment, recovery and counting of microbial cells inoculated on stainless steel. Abstract The aim of this work was to evaluate the resistance of two pathogenic bacteria (Listeria monocytogenes and Salmonella enterica subsp. enterica serotype Senftenberg), and three airborne food‐spoiling filamentous fungi (Hyphopichia burtonii, Penicillium nordicum, and Aspergillus brasiliensis ATCC 16404) to gaseous ozone on stainless steel.

Low‐energy x‐rays can be used to reduce the number of pathogenic microorganisms in fresh produce, but the efficacy of this process against internalized bacteria in leafy greens has not yet been reported. Low‐energy x‐ray irradiation at 1.5 kGy reduced the internalized pathogens by an average of 4.86 log CFU/g in iceberg lettuce without affecting product quality.

Processing of apple juice supplemented with cinnamon essential oils in three different concentrations and processed by pulsed electric field by increased treatment time provided inactivation of endogenous and pathogenic bacteria without adversely affecting the physical, and bioactive properties with an increase in ΔH in thermal properties.

Gelatin‐based encapsulation of Cinnamon EOs and bacteriocins is a practical application to extend the shelf‐life of meatballs. The antibacterial and antioxidant activity of encapsulated formulation has been evaluated. This new method can be used in industry for biopreservation of meat.

Fatty acid amides of palmitic (PAPY), lauric (LAPY), myristic (MYPY), and decanoic (DEPY) acids inhibited bacteria. Significant inhibition of Listeria and other bacteria increased at higher amide concentrations (10,000–20,000 ppm). LAPY reduced Listeria growth by 1.55 to >5.0 Logs in co‐inoculation assays and by 0.51 to >3.00 Log CFU/g on produce. Abstract Foodborne pathogens are a persistent threat to food and consumer safety.

Journal of Food Safety, EarlyView. In this study, the characteristics of Listeria monocytogenes isolated from enoki mushroom (Flammulina velutipes) collected from May to July 2019 were analyzed.

Journal of Food Safety, EarlyView. Ultrafine bubbles (UFB) are a novel concept that has the potential to enhance the potency of antimicrobials to eliminate biofilms.

Journal of Food Safety, EarlyView. This study determined the prevalence, risk factors, and molecular characteristics of Listeria species detected in beef and beef products sampled in Mpumalanga province, South Africa. Four hundred beef and beef products were collected from 30 retail outlets in three districts (Bronkhorstspruit, Emalahleni, and Middelburg) within the province. Standard bacteriological and polymerase chain reaction (PCR) assays were used in the study.

Journal of Food Safety, EarlyView. The objective was to explore the effects of dielectric barrier discharge (DBD) plasma on bacterial reduction, physiological characteristics (pH and moisture), and sensorial quality against Listeria monocytogenes on the surface of smoked salmon. Reductions were treated with 5, 10, 20, 30, 40, 50, and 60 min with DBD plasma varied from 0.17, 0.25, 0.32, 0.70, 0.81, 1.05, and 1.25 log10 CFU/g, respectively.

Journal of Food Safety, EarlyView. As a widespread foodborne pathogen, Listeria monocytogenes (LM) can potentially cause a large number of food safety incidents, and the mortality rate of humans infected with this pathogen is relatively high. Thus, establishment of a fast and simple inspection technology is imperative.

Journal of Food Safety, EarlyView. The increasing incidence of foodborne illnesses worldwide has become an economic and public health problem. In order to reduce the risks associated with food safety, the Normative Instruction n° 79, 2018, modified the inspection of jowl in pork slaughterhouses in Brazil and requires the submission to validated treatments such as heat or other methods approved.

Journal of Food Safety, EarlyView.

Journal of Food Safety, EarlyView. Ultrafine bubble technology is a novel concept in food safety that can improve the potency of antimicrobials against biofilms. This study was conducted to evaluate the impact of gas (air, CO2, or N2) ultrafine bubbles incorporation in 100 and 200 ppm chlorine (Cl2) solutions to inactivate fresh Listeria monocytogenes biofilms on stainless steel.

Journal of Food Safety, EarlyView. Abstract

Journal of Food Safety, EarlyView. Listeria monocytogenes are pathogenic microorganisms and of particular concern in the poultry industry. They are frequently isolated from raw chicken products due to their ability to attach to a wide variety of food and food‐contact surfaces. The application of synthetic antimicrobial agents is often limited by potential emergence of antimicrobial resistance and regulations associated to organic poultry products.

Schematic representation of test system for transfer of L. monocytogenes associated with soil particles to spinach leaves in the presence of antimicrobial agents. Abstract Sporadic contamination of produce with Listeria monocytogenes (Lm) is a recurrent problem. Ways for contamination to occur include transfer of the pathogen to produce from processing surfaces or soil particles to which it has become attached.

The application of bacteriophage P100 to reduce incidence of Listeria sp. in ready‐to‐eat (RTE) food production environments was investigated. Data indicate the application of Listeria specific phage P100 in RTE food production environments can reduce incidence and be considered an additional intervention strategy for controlling this pathogen on NFCS.

The scattering experiment is shown in Figure 1. The aptamer of Listeria monocytogenes is fixed on the bare electrode surface and its complementary DNA sequence (DNA1) labeled with bipyridyl ruthenium is self‐assembled to the electrode surface through base complementary pairing, which keeps the strongest electrochemical luminescence signal.

Co‐microencapsulation of lactobacilli cell free and propolis extract inhibited bacterial growth considerably. Abstract Cell free extracts (CFE) obtained from Lactobacillus plantarum FI 8595 and Lactobacillus reuteri ATCC 55730 alone or in combination with propolis ethanolic or water extracts (1%) were microencapsulated with maltodextrin (25%) before the subsequent spray drying process. They were morphologically characterized by scanning electron microscope.

A new selective broth, SSEL, was developed for simultaneous enrichment of S. enterica, S. aureus, E. coli O157: H7, and L. monocytogenes, optimizing by single factor experiments and a L9 (34) orthogonal test.

Isochoric freezing, different from isobaric (conventional) freezing, has a superior capability to reduce foodborne pathogens (a) photo and (b) schematic of a prototypical isochoric chamber. Abstract Isochoric freezing, different from isobaric (conventional) freezing, allows for storage below freezing temperatures without significant damage from ice formation.

Efficacy of N‐Halamine on Foodborne Pathogens Abstract A major concern of the cattle industry is cross‐contamination of meat with pathogens. Cattle are exposed to fecal material, mud, and other contaminants which harbor pathogens that can be shed onto meat and meat processing equipment. Due to increased chances of meat contamination during processing, new antimicrobial formulations for carcass washing before hide removal needs to be identified and tested.

Antimicrobial effect of oregano and thyme essential oils (1%) in minced pork was assessed after storage at 3°C/7 days in a vacuum. The inhibition of S. Typhimurium depended mainly on the fat content (logarithmic dependence) and to a lesser degree on the pH, whereas pH was not found to be a significant predictor in the case of L. monocytogenes. The results show that only lean minced meat (up to 5% of fat) is a suitable matrix for pathogen control by essential oils.

PDT is an emerging new antimicrobial technology, which uses a combination of photosensitizers and light. This study, for the first time, demonstrated that ERY (Red No. 3)‐mediated PDT can be an alternative antimicrobial treatment strategy to the conventional treatments used in tomato juice. Abstract The objectives of this study were to evaluate the efficacy of erythrosine B (ERY, Red No.

Prolonged exposure of foodborne pathogens (Salmonella Enteritidis [SE], Escherichia coli O157:H7 [EC], and Listeria monocytogenes [LM]) to acid, salt, and cold stress alters their antibiotic resistance. However, the effect of acid, salt, and cold stress on bacterial antibiotic resistance depend on both the bacterial species and the specific antibiotic.