Sweet lupines are increasingly used in food production. Cause for concern has been expressed due to the increase in reported lupine-induced allergic incidents and the association between lupine and peanut allergies. In the current study, a polyclonal-monoclonal antibody-based sandwich ELISA for the detection of lupine proteins in foods was developed. The assay was sensitive to both native and processed proteins from Lupinus angustifolius and Lupinus albus and had a detection limit of 1 mug/g. Intra- and interassay coefficients of variation were <5 and <17%, respectively. A selection of 112 food samples, both with and without lupine declaration, was evaluated for their content of lupine. The data showed that the majority were in agreement with the respective labeling. However, some inconsistency was seen, typically in bread/rolls and soy flours.

The quality of an applied protein extract is important in both serological and in vivo diagnosis of allergy, and for allergen detection methods. In the present study the effects of the extraction procedure and hazelnut source on antibody binding to hazelnut (Corylus avellana) proteins were investigated. An overnight extraction procedure in trisÁ glycine buffer at 458C was compared to a quick, vigorous extraction in a tris buffer at room temperature (RT). Antibody binding was studied by the use of polyclonal antiserum, a monoclonal antibody against the pollen-unrelated allergen Cor a 9, and human IgE from hazelnut allergic individuals. The extraction procedure, as well as the storage time and degree of processing of hazelnuts affected the protein constitution of the extract, as visualised by SDSÁPAGE. Fresh and roasted (10 min at 1708C) hazelnuts generally contained a higher amount of intact hazelnut proteins than elder ( 6 months) raw hazelnuts stored at RT. The time of storage of raw hazelnuts was inversely related to the amounts of Cor a 9 and IgE-binding proteins. In general, a rapid extraction procedure increased the efficacy of protein extraction and antibody-binding capacity to the proteins compared to an overnight extraction protocol. The present study indicates that for the production of hazelnut protein extracts, the use of fresh hazelnuts is important. A quick, vigorous extraction in a tris buffer might contribute positively, at least for extraction of Cor a 9.

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A prototype decision support IT-tool for the food industry was developed in the STARTEC project. Typical processes and decision steps were mapped using real life production scenarios of participating food companies manufacturing complex ready-to-eat foods. Companies looked for a more integrated approach when making food safety decisions that would align with existing HACCP systems. The tool was designed with shelf life assessments and data on safety, quality, and costs, using a pasta salad meal as a case product. The process flow chart was used as starting point, with simulation options at each process step. Key parameters like pH, water activity, costs of ingredients and salaries, and default models for calculations of Listeria monocytogenes, quality scores, and vitamin C, were placed in an interactive database. Customization of the models and settings was possible on the user-interface. The simulation module outputs were provided as detailed curves or categorized as “good”; “sufficient”; or “corrective action needed” based on threshold limit values set by the user. Possible corrective actions were suggested by the system. The tool was tested and approved by end-users based on selected ready-to-eat food products. Compared to other decision support tools, the STARTEC-tool is product-specific and multidisciplinary and includes interpretation and targeted recommendations for end-users.

With the aim of lowering the detection limit for casein in foods, three competitive assays are described: direct time-resolved fluoroimmunoassay (TR-FIA), using europium-conjugated antibody, indirect TR-FIA, using biotinylated antibody with europium-conjugated streptavidin and ELISA, using a HRP-conjugated secondary antibody. Food samples (instant potato, flour mix, packet soup, spice-mix) were analysed. Standard curve sensitivities in direct and indirect TR-FIAs did not differ significantly (p0/0.097), but both TR-FIAs were considerably less sensitive (both p B/0.0001) than ELISA (LOQs 1.3, 1.5 and B/1.0 mg kg (1 , respectively). The precision and working analyte range was similar in all three methods. Casein content measured in food products was comparable, using the three assays and rocket immunoelectrophoresis. The TR-FIA approach provided no improvement over the ELISA. All three assays allowed quantification of casein in foodstuffs in the order of 1 Á/1.5 mg kg (1 , providing a basis for more rigorous validation and collaborative testing.