Rapid Full-Cycle Technique to Control Adulteration of Meat Products: Integration of Accelerated Sample Preparation,Recombinase Polymerase Amplification,and Test-Strip Detection

Verifying the authenticity of food products is essential due to the recent increase in counterfeit meat-containing food products. The existing methods of detection have a number of disadvantages. Therefore, simple, cheap, and sensitive methods for detecting various types of meat are required. In this study, we propose a rapid full-cycle technique to control the chicken or pig adulteration of meat products, including 3 min of crude DNA extraction, 20 min of recombinase polymerase amplification (RPA) at 39 °C, and 10 min of lateral flow assay (LFA) detection. The cytochrome B gene was used in the developed RPA-based test for chicken and pig identification. The selected primers provided specific RPA without DNA nuclease and an additional oligonucleotide probe. As a result, RPA–LFA, based on designed fluorescein- and biotin-labeled primers, detected up to 0.2 pg total DNA per μL, which provided up to 0.001% w/w identification of the target meat component in the composite meat. The RPA–LFA of the chicken and pig meat identification was successfully applied to processed meat products and to meat after heating. The results were confirmed by real-time PCR. Ultimately, the developed analysis is specific and enables the detection of pork and chicken impurities with high accuracy in raw and processed meat mixtures. The proposed rapid full-cycle technique could be adopted for the authentication of other meat products.     

New generation of fire retardant polyester resins

Smoke evolution [in a smoke chamber (750 x 750 x 1000) ± 5 mm, Polish Standard PN-91/K-02501 equivalent to UIC 561-OR (1991)] was studied in, and the oxygen index flammability test (Polish Standard PN-76/C-89020) was carried out for, glass-reinforced polyester (GRP) laminates obtained with unsaturated polyester (UP) resins containing chlorine and bromine in the chain. In these studies, the effect on these properties of such additives as ZnSnO₃ (ZS), ZnSn(OH)₆ (ZHS), Al(OH)₃ or Mg(OH)₂ and Sb₂O₃ in an amount of up to 30 mass-% was determined. The most efficient ignition and smoke-evolution retarder from among the investigated compounds was ZS and ZHS, whereas an essential reduction in smoke evolution was observed also with Sb₂O₃. GRP laminates with these additives meet the fire-safety recommendations concerning smoke evolution from materials used in transportation means and in the building industry.