Sesame, Pistachio, and Macadamia Nut: Development and Validation of New Allergenic Systems for Fast Real-Time PCR Application.

Food allergy is a worldwide health problem that concerns infants to adults. The main health risk for sensitised individuals is due to the presence of traces of allergens as the result of an accidental contamination during food processing. The labelling of allergens such as sesame, pistachio, and macadamia nut on food products is mandatory according to Regulation (EU) N. 1169/2011; therefore, the development of suitable and specific analytical methodologies is advisable. The aim of this study was to perform a multi-allergen real-time PCR system that works well in fast mode at the same annealing temperature and with the same thermal profile. The real-time PCR was developed designing new, specific, and efficient primer and probe systems for the 2S albumingene for sesame and pistachio and for the vicilin precursorgene for macadamia nut. These systems were subjected to a robust intra-laboratory qualitative validation process prior to their application, by DNA extraction and fast real-time PCR, on some real market samples to reproduce a potential allergen contamination along the food chain. The developed system results were specific and robust, with a sensible limit of detection (0.005% for sesame; 0.004% for pistachio; 0.006% for macadamia nut). The performance and the reliability of the target systems were confirmed on commercial food samples. This molecular approach could be used as a screening or as a support tool, in association with the other widespread monitoring techniques (such as ELISA).

Indicators of protein spoilage in fresh and defrosted crustaceans and cephalopods stored in domestic condition.

In relation to consumer demand, crustaceans and cephalopods are sold as both fresh and defrosted. It is well known that total volatile basic nitrogen (TVB-N) and volatile amine values, especially, biogenic amines and biogenic amine index, are expression of freshness of fish products, but there is a lack of knowledge of their acceptability limits, for crustaceans and cephalopods. In order to assess these limits, real-time shelf life tests were carried out, relating the results of TVB-N, biogenic amines and BAI to the sensory evaluation of crustaceans and cuttlefishes, both fresh and defrosted. TVB-N and biogenic amines have been analysed in many shrimp species and cuttlefishes purchased in Perugia (Central Italy), and BAI was calculated as the ratio between different biogenic amines. The results show levels of TVB-N and spermine different between shrimp and cuttlefish (TVB-N: 37 vs. 14 mg/100 g; spermine: 4 vs. 14 mg/kg, respectively) while the other biogenic amines and BAI are close to zero in both. Among biogenic amines, cadaverine and even more putrescine significantly affect BAI values and seem to be the most effective in assessing limits of acceptability during storage.

Foreign Bodies in Dried Mushrooms Marketed in Italy.

The presence of foreign bodies in mushrooms affects their marketability and may result in health risks to consumers. The inspection of fresh or dried mushrooms today is very important in view of the increased consumption of this kind of food. Ten samples of dried mushrooms collected in supermarkets were examined for evidence of entomological contamination by macro and microscopic analytical methods, the so-called filth-test. A total of 49 46 determinations, comprising 15 g of the vegetable matrix, were made. The microscopic filth test consistently detected an irregular distribution of physical contaminants following repeated determinations of the same sample. Visual examination, on the other hand, was not sufficient to ensure a product free of contaminants.