Research Publications (Food Safety)

Fungi belonging to the genus Alternaria are common pathogens of fruit and vegetables with some species able to produce secondary metabolites dangerous to human health. Twenty-eight Alternaria isolates from rocket and cabbage were investigated for their mycotoxin production. Five different Alternaria toxins were extracted from synthetic liquid media and from plant material (cabbage, cultivated rocket, cauliflower). A modified Czapek-Dox medium was used for the in vitro assay.

Toxoplasma gondii is a globally distributed parasitic protozoan that infects humans and other warm-blooded vertebrates. Felids are the only definitive host for T. gondii, and they excrete oocysts in their faeces. The national prevalence in humans is declining in the United States. This zoonotic organism is of particular interest due to its importance in pregnant women, in individuals with altered immune systems, and in reactivated ocular infections.

The genus Campylobacter comprises members known to be a leading cause of foodborne gastrointestinal illness worldwide. A study was conducted to determine the epidemiology and antimicrobial resistance of Campylobacter in humans in Morogoro, Eastern Tanzania. Isolation of Campylobacter from stool specimens adopted the Cape Town protocol.

Vibrio vulnificus is a marine bacterium associated with human and fish (mainly farmed eels) diseases globally known as vibriosis. The ability to infect and overcome eel innate immunity relies on a virulence plasmid (pVvbt2) specific for biotype 2 (Bt2) strains. In the present study, we demonstrated that pVvbt2 encodes a host-specific iron acquisition system that depends on an outer membrane receptor for eel transferrin called Vep20.

Publication date: August 2015
, Volume 54
Author(s): Mário Paz , Luísa Correia-Sá , Helena Becker , Elisane Longhinotti , Valentina F. Domingues , Cristina Delerue-Matos

Publication date: August 2015
, Volume 54
Author(s): Trond Løvdal

Publication date: August 2015
, Volume 54
Author(s): David J. Hsi , Eric D. Ebel , Michael S. Williams , Neal J. Golden , Wayne D. Schlosser

Hirotaka Hiyoshi, Ryu Okada, Shigeaki Matsuda, Kazuyoshi Gotoh, Yukihiro Akeda, Tetsuya Iida, Toshio Kodama

Electronic noses (e-noses) have been used for environmental monitoring, standardization of medicinal flavourings, food safety tests, and diagnosis of infectious diseases based on the statistical analysis of volatile organic compounds (VOCs). Bovine tuberculosis (bTB) is officially diagnosed using the intradermal skin test (IST), which is time-consuming and labour-intensive. Therefore, a more convenient and rapid test with greater sensitivity would be advantageous as pre-screening test.

Abstract

BACKGROUND

Acrylamide (AA) is a potential carcinogen which widely exists in heat-processed foods. The addition of glycine (Gly) has been shown to reduce the formation of AA. The objective of this work was to investigate the kinetics of the inhibition of AA by Gly in both asparagine (Asn)/glucose (Glc) and Asn/Glc/Gly potato model systems during heating at 160 °C, 180 °C, and 200 °C.

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.

To the Editor: Noroviruses are nonenveloped viruses of the family Caliciviridae with a single-stranded RNA genome. In developing countries, noroviruses cause >200,000 deaths annually among children <5 years of age (1). Noroviruses are divided into 6 genogroups, GI–GVI, which are further divided into genotypes. Twenty-nine of the genotypes cause human infections (2).

Phylogenetic analysis of influenza viruses collected during December 2009–February 2010 from chickens in live poultry retail shops in Lahore, Pakistan, showed influenza A(H9N2) lineage polymerase and nonstructural genes generate through inter- and intrasubtypic reassortments. Many amino acid signatures observed were characteristic of human isolates; hence, their circulation could enhance inter- or intrasubtypic reassortment.

Resistant starch type IIIRS3) was produced from sago (Metroxylon sagu) and evaluated for its characteristics as a prebiotic. Two RS3 samples designated sago RS and HCl-sago RS contained 35.71% and 68.30% RS, respectively, were subjected to hydrolyses by gastric juice and digestive enzymes and to absorption. Both sago RS and HCl-sago RS were resistant to 180 min hydrolysis by gastric acidity at pH 1 to 4 with less than 0.85% hydrolyzed.

Publication date: 18 May 2015
, Volume 201
Author(s): V. Carraro , C. Sanna , V. Brandas , A. Sanna , A. Pinna , V. Coroneo

Fang He, Ying Fu, Qiong Chen, Zhi Ruan, Xiaoting Hua, Hua Zhou, Yunsong Yu

This paper reports on the effect of carbon dioxide concentration on the formation of biogenic aminesBAs) in shredded cooked chicken breast fillet packed in modified atmosphere stored at 4C. The samples were grouped as follows: T1 (packed under atmospheric air), T2 (vacuum packaged), T3, T4, T5, T6 and T7 (packaged under modified atmosphere with 10, 30, 50, 70 and 90% CO2, respectively, and total volume completed with N2).

Ying Yu, Lihua Fang, Yan Zhang, Hongxia Sheng and Weihuan Fang Type VI secretion system (T6SS) is a macromolecular transenvelope machine encoded within the genomes of several proteobacteria species. Vibrio parahaemolyticus contains two putative T6SS systems, VpT6SS1 and VpT6SS2, both contributing to adherence to Caco-2 and/or HeLa cells. However, it remains unknown if these systems are involved in cellular responses.

We identified 3 lineages among multidrug-resistant (MDR) Salmonella enterica serotype Typhi isolates in the Gulf of Guinea region in Africa during the 2000s. However, the MDR H58 haplotype, which predominates in southern Asia and Kenya, was not identified. MDR quinolone-susceptible isolates contained a 190-kb incHI1 pST2 plasmid or a 50-kb incN pST3 plasmid.

In the United States, empirical information on the sustainability of commercial-scale egg production is lacking. The passage of state regulations specific to hen housing created urgency to better understand the effects of different housing systems on the sustainability of the egg supply, and stimulated the formation of a coalition, the Coalition for a Sustainable Egg Supply (CSES), to conduct research on this topic.

The objectives of the two studies presented were to estimate the prevalence of Campylobacter-positive farms and flocks and to acquire updated knowledge about risk factors for the introduction of Campylobacter in Danish broiler flocks. In the first study, from September 2010 to September 2011, there were 25 Danish broiler farms visited, and a questionnaire was filled in by a veterinarian/consultant.

Hen housing for commercial egg production continues to be a societal and regulatory concern. Controlled studies have examined various aspects of egg safety, but a comprehensive assessment of commercial hen housing systems in the US has not been conducted. The current study is part of a holistic, multidisciplinary comparison of the diverse aspects of commercial conventional cage, enriched colony cage, and cage-free aviary housing systems and focuses on environmental and egg microbiology.

Storage tests under different temperatures (2, 4, 10, and 15°C) were conducted to identify the best predictor variable that is most effective to explain the loss of the shelf life and quality of modified atmosphere packed (MAP) poultry, and constitutes the basis for the prediction of the remaining shelf life. The samples were packed in 70% O2 and 30% CO2, which is the common used gas atmosphere for poultry filets in Germany.