Development of a reference material for Staphylococcus aureus enterotoxin A in cheese: Feasibility study, processing, homogeneity and stability assessment

Abstract

Staphylococcal food poisoning is caused by enterotoxins excreted into foods by strains of staphylococci. Commission Regulation 1441/2007 specifies thresholds for the presence of these toxins in foods. In this article we report on the progress towards reference materials (RMs) for Staphylococcal enterotoxin A (SEA) in cheese. RMs are crucial to enforce legislation and to implement and safeguard reliable measurements. First, a feasibility study revealed a suitable processing procedure for cheese powders: the blank material was prepared by cutting, grinding, freeze-drying and milling. For the spiked material, a cheese-water slurry was spiked with SEA solution, freeze-dried and diluted with blank material to the desired SEA concentration. Thereafter, batches of three materials (blank; two SEA concentrations) were processed. The materials were shown to be sufficiently homogeneous, and storage at ambient temperature for 4weeks did not indicate degradation. These results provide the basis for the development of a RM for SEA in cheese.

Health risk assessment of various metal(loid)s via multiple exposure pathways on children living near a typical lead-acid battery plant, China

“…Secondly, certain uncertainties during dose-effect simulation experiments may exist in quantitative risk assessment (Xia et al, 2010). Additionally, the variance during the sample analysis and homogeneity could also bring about certain uncertainties (Zeleny et al, 2015). However, animal experiments to quantify the bioavailability of each pollutant in human metabolism are costly and would cause ethical concerns, while in vitro digestion models are not suitable for assessing the inhalation and dermal exposure.…”

Inhibition of Staphylococcus aureus cocktail using the synergies of oregano and rosemary essential oils or carvacrol and 1,8-cineole

“…Staphylococcus aureus is a pathogen frequently associated with food outbreaks causing a typical intoxication through the ingestion of enterotoxins pre-formed in foods ( Zeleny et al, 2015 ). Cheeses and meats have been frequently involved in major outbreaks of staphylococcal intoxication worldwide ( Wang et al, 2013 ; Zeleny et al, 2015 ).…”

“…Staphylococcus aureus is a pathogen frequently associated with food outbreaks causing a typical intoxication through the ingestion of enterotoxins pre-formed in foods ( Zeleny et al, 2015 ). Cheeses and meats have been frequently involved in major outbreaks of staphylococcal intoxication worldwide ( Wang et al, 2013 ; Zeleny et al, 2015 ). Thus, the development of strategies to control this bacterium in these food matrices is of great importance for researchers and food industry ( Pimentel-Filho et al, 2014 ; Pesavento et al, 2015 ).…”

Biological toxins of potential bioterrorism risk: Current status of detection and identification technology

“…is encountered and has to be overcome: by taking a step-wise approach, using methods which are well understood and perform satisfyingly as thoroughly assessed in in-house and interlaboratory validation studies as well as suitable PT rounds. In this context, JRC-IRMM in close collaboration with Anses is currently working on making available a set of CRMs for the detection of SEA in cheese at a pg/g level [88]. Similar concepts should be applied to other matrix CRMs for biological toxins in the future.…”