Livestock welfare is an important condition for obtaining high-quality and safe food. According to the legislation edible insects are classified as livestock; and for this reason it is necessary to comply with the edible insect welfare conditions. This article focuses on selected welfare conditions for mealworm (Tenebrio molitor) breeding, with special focus on the fat content influenced by different breeding temperature (17 °C, 23 °C and 28 °C). Maximum fat content 24.56% was observed at 23 °C. To obtain maximum fat content this appears to be the optimal breeding temperature. Another evaluated aspect was the nutritional stress and a way of killing, and their impact on fat content, which showed to decrease with the nutrient stress. The most decline was detected towards the end of the observation period. The analysis showed that in terms of preservation of the fat content, the best way is killing by freezing, due to the metabolism slowdown. We also analysed the content of heavy metals in a mealworm larvae using cyclic voltammetry with subsequent evaluation. In the measured sample concentrations of heavy metals did not exceed the maximum allowable concentration of heavy metals in this commodity. From this point of view mealworm appears to be a safe food.

All reinforcements for polymer-matrix composites must be coated with a suitable material in the form of a thin film to improve compatibility and interfacial adhesion between the reinforcement and the polymer matrix. In this study, plasma nanotechnology was used to synthetize such functional nanocoatings using pure tetravinylsilane (TVS) and its mixtures with oxygen gas (O2) as precursors. The plasma-coated glass fibers (GFs) were unidirectionally embedded in a polyester resin to produce short composite beams that were analyzed by a short-beam-shear test to determine the shear strength characterizing the functionality of the nanocoatings in a GF/polyester composite. The developed plasma nanocoatings allowed controlling the shear strength between 26.2–44.1 MPa depending on deposition conditions, i.e., the radiofrequency (RF) power and the oxygen fraction in the TVS/O2 mixture. This range of shear strength appears to be sufficiently broad to be used in the design of composites.

Edible insect can be a valuable source of nutrients, but also a potential source of heavy metals. Quick detection of overlimit heavy metals concentration could be a key to processing and quick distribution of edible insect products. The aim of this work was to evaluate the feed-dependent content of heavy metals in the mealworm and superworm using the X-ray fluorescence spectrometry as an easy, cheap and a timeless screening method for evaluating the content of heavy metals and microelements. Using a handheld analyser the content of Cd, Pb, Cu and Zn were detected. Both analysed species proved dependency of metal content on a feed. Detected level of Cu in mealworm was between 571 mg.kg -1 and 1768 mg.kg -1 and in superworm from 571 mg.kg -1 to 1768 mg.kg -1 based on the feed. The content of Zn was similar, between 725 mg.kg -1 and 1437 mg.kg -1 in mealworm and 555-1482 mg.kg -1 in superworm. The level of Pb was below the detection limit in all samples, thus from this point of view this food seems to be safe. On the contrary, the content of Cd in the dry matter samples was above the food limit -147 mg.kg -1 to 230 mg.kg -1 . From this point of view, the samples were evaluated as unsuitable for consuming.

Edible insect is appraised by many cultures as delicious and nutritionally beneficial food. In western countries this commodity is not fully appreciated, and the worries about edible insect food safety prevail. Electronic noses can become a simple and cheap way of securing the health safety of food, and they can also become a tool for evaluating the quality of certain commodities. This research is a pilot project of using an electronic nose in edible insect culinary treatment, and this manuscript describes the phases of edible insect culinary treatment and methods of distinguishing mealworm (Tenebrio molitor) and giant mealworm (Zophobas morio) using simple electronic nose. These species were measured in the live stage, after killing with boiling water, after drying and after inserting into the chocolate.The sensing device was based on the Arduino Mega platform with the ability to store the recorded data on the SD memory card, and with the possibility to communicate via internet. Data analysis shows that even a simple, cheap and portable electronic nose can distinguish between the different steps of culinary treatment (native samples, dried samples, samples enriched with chocolate for cooking) and selected species. Another benefit of the electronic nose could be its future introduction into the control mechanisms of food security systems (e.g. HACCP).

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