Research Publications (Food Safety)

Camel milk is highly nutritious but contamination with biofilm forming methicillin resistant Staphylococcus aureus (MRSA) may pose a serious threat to human health and food safety. Therefore, sinapic acid (SA) was assessed for its in vitro antibiofilm and antivirulence potential against MRSA isolated from raw camel milk samples.

Minas frescal cheese (MFC) is a potential vehicle for Shiga toxin-producing Escherichia coli (STEC) O157:H7. The effect of electron beam irradiation on the control of STEC O157:H7 in artificially contaminated MFC (5 log cfu g-1) was evaluated. Samples were irradiated at doses of 1.0, 1.5, and 2.0 kGy and evaluated for 40 days at 4 °C. Shelf life extension and the stability of the lipid fraction of the cheeses were also evaluated.

Seasonal variation in the prevalence and antimicrobial resistance of Campylobacter species in the Ethiopian dairy value chain was investigated. Dairy food samples (456) were collected in the dry and wet seasons in three regions of Ethiopia. Campylobacter species were detected in 20% of samples collected in the wet season. The overall prevalence did not differ significantly between the wet and dry seasons.

The capacity for biofilm formation andslime production, the enterotoxigenic potential and the molecular typing of 20 Staphylococcus aureus isolated from minas frescal and Porungo cheeses was evaluated. Profiles obtained by Rep-PCR enabled the isolates to be grouped into two major subgroups. All S. aureus isolates were capable of forming biofilms, with the majority falling under the category of strong biofilm formers.

Staphylococcus aureus is one of the major foodborne pathogens contaminating milk and milk products. Isolates recovered from different stages in the cheese production chain and food processing environment (n = 16) in Poland were characterised using whole genome-sequencing and bioinformatic analyses. Most strains belonged to multi-locus sequence type (MLST) ST109 (6/37.5%) and ST130 (3/18.8%). Spa-typing of S.

Escherichia coli O157:H7 is harmful to humans by producing toxins that cause thrombotic thrombocytopenic purpura and haemolytic uraemic syndrome. Real-time recombinase-aided amplification (rRAA) can generate real-time fluorescence signals to achieve sensitive detection of pathogens within 20 min but cannot distinguish dead bacteria from viable bacteria, leading to false-positive results.

Staphylococcus aureus (S. aureus) is one of the most important causes of foodborne illness. Due to the interest of people to use traditional dairy products, especially milk, in the current descriptive study the frequency of S. aureus, antibiotic resistance pattern and presence of toxic shock syndrome toxin-1 gene (tsst-1 gene) in these isolated strains was investigated. Thirty-nine strains (26%) of S.

The prevalence of L. monocytogenes in bovine milk from different regions of Yunnan Province, Southwest China, was investigated. The isolated strains were genotyped using pulsed-field gel electrophoresis (PFGE), and their virulence and antibiotic resistance potential analysed with whole-genome sequencing (WGS). A total of 8 L. monocytogenes strains were isolated from 4 out of 161 samples, with a detection rate of 2.48%.

Bovine milk is a low cost, high nutritional value product commercialised worldwide. To maintain high standard levels and preserve consumer health, several tests could be used to identify antimicrobial drug residues, run voluntarily or officially planned and performed, according to European legislative requirements.

The prevalence and resistance of C. jejuni in small ruminants in Jordan to antimicrobials of human clinical importance and the management factors that associate with C. jejuni in the flocks were determined. Flock-level prevalence of C. jejuni was 28.5%; individual animals’ prevalence was 11.0%.

It is important to understand the distribution of strains of Bacillus cereus that produce the emetic toxin, cereulide, in raw milk, and to evaluate their impact on the safety of milk and dairy products. The distribution of cereulide-producing B. cereus was investigated for isolates from raw milk in Hokkaido, Japan, and the ability of strains to produce cereulide in milk was also studied.

The lethal effect of high hydrostatic pressure processing (HPP), expressed as D-value, on some common pathogens found in low salt white brined cheese was studied.

A novel saltatory rolling circle amplification (SRCA) assay was established for prompt identification of L. monocytogenes in milk and Indian milk cake (kalakhand). The SRCA and conventional PCR were independently able to detect 63 fg and 630 fg L. monocytogenes DNA per reaction, respectively. The detection limit of SRCA was evaluated in artificially contaminated milk and kalakhand.

Cross-sectional research aimed to identify Staphylococcus aureus from milk, yoghurt, and cheese collected from selected towns in the west Showa zone was conducted from May 2020 to March 2021. The isolates were identified based on colony characterisation, Gram stain, and coagulase tests, and matrix assisted laser desorption/ionisation time-of-flight biotyper. The drug susceptibility test was conducted using the disk diffusion method.

The survival of E. coli O157:H7 strain (NCTC 12900) was assessed in raw donkey milk, in mild pasteurised donkey milk (50 ° C for 30 min), in donkey milk processed by HP at 400 MPa at 3 °C for 60 s, and in donkey milk treated with a combination of the two technologies. The results showed that E. coli O157:H7 was able to survive in raw donkey milk for 15 days and in mild pasteurised donkey milk for 4 days.

This study aimed to establish a mathematical model capable of predicting the adhesion and biofilm formation by Bacillus cereus isolates on stainless steel surface under different combinations of pH, temperature and time. Logistic regression models were developed to predict the probability of adhesion or biofilm formation on the surface by the pathogen.

Meta-analysis was used to investigate the concentration and prevalence of AFM1 in different types of cheese consumed in Iran. The results demonstrated that the pooled estimated mean of AFM1 concentration in Iranian cheese was 130.65 ng kg-1 (95% CI: 110.43, 150.86), while the percentage of AFM1 positive samples were 66.56% (95% CI: 56.82, 76.30).

Milk is a source of bioactive proteins with defensive properties, of great value for protecting the newborn. The activity of bovine milk lactoferrin (LF) was investigated as an antibacterial agent in the internalisation of the emergent pathogen Cronobacter sakazakii into Caco-2/TC7 cells, a model of human intestinal epithelium. The effect of LF on oxidative stress and expression of Toll-like receptors (TLR) was also investigated.

A portable toolbox based on time-resolved fluoroimmunoassay and immunomagnetic separation was designed for on-site detection of Cronobacter sakazakii in dairy without advanced facilities. In this study, C. sakazakii was recognised and captured in milk by immunomagnetic beads, and europium chelated nanoparticles were used as signal probes in fluoroimmunoassays for quantitative analysis.

Contamination of dairy products such as milk by Campylobacter species can occur due to faecal contamination and incomplete pasteurisation or post-pasteurisation steps. Studies describing the contamination of milk with Campylobacter species were retrieved by searching in international general and specific databases between January 2000 and May 2021.

The study was carried out on the assumption that raw materials for butter production by the traditional batch churning method can be contaminated with Listeria monocytogenes cells. Raw milk and cream used in butter making were experimentally contaminated with the pathogen, and two contamination scenarios were considered. In the first variant, it was assumed that cream for butter making is contaminated with L. monocytogenes.

Rapid screening and early warning of pathogenic bacteria in food is the key to prevent and control the spread of foodborne diseases. Biotin–streptavidin system and membrane filtration technology were combined to develop a novel nuclear magnetic resonance (NMR) immunosensor based on biomacromolecule O-carboxymethyl chitosan (O-CMCS) target gadolinium (Gd) probe for rapid detection of Salmonella anatum in milk.

The survivability and thermal resistance of L. monocytogenes was determined in dry and hydrated nonfat dry milk (NFDM) and whole milk powder (WMP) during 180 days of storage. The hydrated milks were prepared from stored, inoculated milk powders on the day of D- and z-value analyses. The overall L. monocytogenes population in milk powders was 7.0 log cfu g-1 on day 1, which reduced by ∼2.2 log cfu g-1 at the end of storage.