Research Publications (Food Safety)

The study investigated fresh tomato fruits (Roma VF variety) prepared into paste, proportioned into different samples with each receiving different concentrations of ginger, ginger and garlic powder (2 and 4% w/w) and stored over a period of 8 weeks. The total viable (TVC), lactic acid bacteria (LAB) and yeast counts of the samples were enumerated on a weekly basis while the pure microbial isolates were identified.

Cronobacter species are foodborne pathogens associated with neonatal meningitis, sepsis and necrotizing enterocolitis through consumption of contaminated powdered milk. However, there are no specific targets used for differentiating Cronobacter species. The DNA-based assay and polyphasic analysis have facilitated the detection and typing of Cronobacter species in foodborne outbreaks. In this study, polymerase chain reaction (PCR) and dot hybridization for detecting Cronobacter spp.

Following a large outbreak of Shiga toxin-producing Escherichia coli (STEC) O157 infection in 2012, the prerequisite program for the production of pickles in Japan was revised to include disinfection with sodium hypochlorite (NaClO). Here, we examined the indicator bacterial counts, incidence of STEC and Salmonella spp.

Escherichia coli is one of the foodborne pathogens associated with several cases of human sickness. Duck meat is an excellent source of animal-derived high quality proteins. This study was undertaken to investigate the possible transmission of diarrheagenic E. coli from consumption of duck meat and giblets. Additionally, expression of some virulence-associated genes in the isolated E. coli serotypes was examined using polymerase chain reaction.

Biofilm of Cronobacter sakazakii on food contact surfaces is the important source of persistent contamination in powdered infant formula. This study aimed to assess the effects of Ca2+ and Mg2+ on biofilm formation. Results indicated that the biofilm-forming ability was strain specific and divalent cation concentrations dependent. Most of C. sakazakii formed the highest amount of biomass at 1.50% MgCl2 (17 strains, 74%) and 0.25% CaCl2 (10 strains, 43.4%).

Conventional methods for the detection of Salmonella based on culturing are time-consuming and laborious. The aim of this study was to develop a template preparation method and polymerase chain reaction (PCR) assay for the detection of Salmonella spp. in egg yolk, pizza, ground beef, pork, pork sausage, chicken drumsticks, mayonnaise and Minas cheese. The DNA extraction was performed with thermal lysis followed by nucleic acid purification with phenol-chloroform.

Lipids are soluble in organic solvents and staphylococcal enterotoxins are water-soluble. This recognized feature can assist in the recovery of these toxins. Partitioning studies were conducted using a toxin-insoluble organic solvent (CHCl3) treatment for the extraction of toxins from the lipid portion of the tested food products.

In Iran, wheat is one of the most important sources of diet. Unfortunately, it is vulnerable to contamination with fungi consisting of aflatoxigenic moulds. Since 1997, ozone has been recognized as an effective oxidant and disinfection agent. This study demonstrates the benefits derived from ozone in the inhibition of Aspergillus parasiticus growth and aflatoxin production in wheat.

The aim of this study was to investigate the effect of ultraviolet (UV)-C treatment on the decrease of the inoculated Staphylococcus aureus population in precooked shredded bullfrog meat. The precooked meat was inoculated with 8 log cfu/g of S. aureus. The packaged bullfrog's back meat was then exposed to low (0.65 mW/s/cm2), medium (1.04 mW/s/cm2) and high (1.68 mW/s/cm2) UV-C intensities over different time intervals (60, 100 and 140 s).

Veal cutlets were surface inoculated with ca. 6.6 cfu/g of an eight-strain rifampicin-resistant cocktail of Shiga toxin-producing Escherichia coli (STEC) (O26:H11, O45:H2, O103:H2, O104:H4, O111:H-, O121:H19, O145:NM and O157:H7). Cutlets were mechanically tenderized and cordon bleu was prepared by adding slices of ham and cheese between two cutlets prior to batter/breading and cooking. Fully assembled cordon bleu were cooked in preheated (191.5C) extra virgin olive oil (45 mL) on a griddle.

This study aimed to evaluate certain microbiological quality characteristics, titration acidity and pH values, Staphylococcus aureus counts, presence of Salmonella spp. in ice cream by conventional and immunomagnetic separation (IMS) methods. Also, the antibiotic susceptibility of Salmonella spp. isolates was demonstrated by 10 different antibiotic disks. For this purpose, 55 ice cream samples were collected from markets and pastries and analyzed in terms of the specified parameters.

The key factors influencing histamine accumulation in fermented sausages were investigated. Although Lactobacillus salivarius R06 with positive amino acid decarboxylase was inoculated, histamine was not detected in batch A without histidine availability. About 52.1 mg/kg of histamine was observed in batch B with the addition of 80 mg/kg histidine. Under sterilized condition, both histamine production and histamine-forming bacteria were not detected in batch C.

Five enterococcal strains (Enterococcus faecalis LS15, PF03, BF10 and SL13 and Enterococcus faecium MM08) were isolated and identified from 130 probiotic products marketed in China. The determined biological characteristics were acid tolerance, bile tolerance, pepsin tolerance, trypsin tolerance, organic acid production and antimicrobial activity. Safety examination of potential virulence factors and antibiotic resistance were also performed.

Loop-mediated isothermal amplification (LAMP) based on lmo0460 sequence in genome of Listeria monocytogenes (L. monocytogenes) was designed for detection of L. monocytogenes, which is an important foodborne kind of pathogenic bacteria causing human and animal disease. The primers set for lmo0460 sequence encoding membrane-associated lipoprotein consist of four specific primers targeting six regions on specific fragment.

The aim of this study is to investigate the antibacterial characteristics and mechanisms of nutmeg oil. In this paper, 54 chemical compositions of nutmeg oil were analyzed by gas chromatography–mass spectrometry (GC–MS). The major volatile components of nutmeg oil were sabinene (39.12%) and alpha-pinene (11.96%).

The objective of this study was to establish quantitative evaluation models for fish microbiological quality analysis based on electronic tongue technique coupled with nonlinear pattern recognition algorithms. Crucian carp stored at 4C were used. A commercial electronic tongue system was employed. The total viable counts (TVCs) of fish samples were measured by the classical microbiological plating method.

This study was conducted to confirm the synergistic inactivation effect of flower pollen when applied with heat treatment to Escherichia coli O157:H7. The reduction of the number of E. coli O157:H7 was monitored during heat treatment at 55, 57.5, 60, 62.5 and 65C.

Chitosan beads were prepared by the method of inverse suspension cross-linking characterized and applied to remove patulin from aqueous solution. Batch adsorption experiments were performed to evaluate the optimum adsorption conditions and reusability. The results showed that chitosan beads were effective in removing patulin from aqueous solution. The maximum adsorption capacity of chitosan beads for patulin was 626.4 μg/g at pH 7.0, 40C for 24 h.

A novel procedure on vancomycin, α-glucosidase activity, cephalothin and sucrose for isolation of Cronobacter spp. from powdered infant formula (PIF) was developed. Meanwhile, a comparison between the new procedure, Druggan-Forsythe-Iversen (DFI) and modified lauryl sulfate tryptose (mLST) procedure was also carried out. The recovery rate is higher by the new procedure than those by DFI and mLST procedures.

The time-to-detection (TTD) method is a rapid and high throughput approach for the estimation of microbial growth parameters (maximum specific growth rate μmax and lag phase duration λ), which relies on optical density (OD) measurements. The performance of this method depends on several factors that are often selected in an arbitrary way.

The study involved 75 autochthonous lactic acid bacteria (LAB) obtained from Valtellina Casera Protected Designation of Origin cheese and provides data on their antibiotic resistance (AR), antimicrobial activity and safety aspects. High biodiversity was revealed, assigning the isolates to 16 species. In the curd Streptococcus thermophilus was predominant, while Enterococcus and the Lactobacillus casei group prevailed in ripened cheese.

In this study, adaptive neuro-fuzzy inference system (ANFIS) and genetic algorithm–artificial neural network (GA-ANN) models were used to predict inactivation of Salmonella enteritidis by ultrasound. The effect of amplitude levels, duty cycles and irradiation time of ultrasound on inactivation of S. enteritidis was investigated.

The majority of foodborne illness outbreaks can be linked to cross-contamination events through contact with contaminated surfaces. Consequently, there is a sustained interest in developing antimicrobial coatings such as silver zeolite to reduce contamination levels. In this study, we examined the efficacy of silver zeolite for preventing biofilm formation by common foodborne pathogens such as Listeria innocua Seeliger and Escherichia coli O157:H7.

This paper investigates the factors that are affecting food safety in Canada today, and those that will become increasingly important in the future. The tools used to complete this analysis are primarily the review of scientific and “gray” literature, and the analysis of multiple sources of data. We develop a methodology for ranking the factors and rank the factors according to their predicted effect on foodborne disease in Canada.

Winter salad is a kind of pickle made of different vegetables and is consumed specially in Khorasan Province. The spontaneous fermentation process is mainly carried out by lactic acid bacteria (LAB). The aim of this study was to isolate and identify the LAB species involved in winter salad fermentation at different fermentation time intervals to introduce the native strains.