The growing interest in functional food makes looking for new possibilities of enriching products with health-promoting ingredients necessary. One raw material with a very high potential for the food industry is the oyster mushroom (Pleurotus ostreatus), which has a strong antioxidant, antiviral, and anticancer effect. Carp meat (Cyprinus carpio) also has beneficial properties. It is rich in easily digestible protein, vitamins, minerals, and omega-3 fatty acids. This study aimed to evaluate the effect of oyster mushroom addition on the quality of carp burgers, with particular emphasis on the antioxidant effect. The scientific literature produced so far has not focused on the synergy between oyster mushrooms and carp meat. The addition of oyster mushrooms contributed to the increase in antioxidant properties and sensory attractiveness of burgers. The fat content in the finished product was reduced, and the degree of their oxidation was also reduced. The obtained results will contribute to the creation of innovative food products that meet the expectations of consumers looking for healthy food.

Smoking is one of the oldest technologies for processing and preserving raw materials of animal origin. To this day, smoked fish is very popular among consumers. The most popular smoked fish is salmon. The research compared the qualitative changes in the fat fractions of hot and cold-smoked salmon during refrigerated storage. Generally accepted physicochemical methods for assessing the quality of fats, such as peroxide, anisidine, and acid number, were used. First, the smoked salmon was stored, and then, the samples were analyzed to find changes in the fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). It was shown that cold smoking significantly inhibited the increase in the level of lipid oxidation compared to hot smoking and raw samples stored in the same way. In the meat of stored and cold- and hot-smoked salmon, the TOTOX values remained at the level indicated by the Codex Alimentarius. Hot smoking limited the degree of lipid hydrolysis during storage as compared to cold smoking. The smoking process had a protective effect on EPA and DHA acids. In the raw samples, the loss of these acids was three times higher. Summarizing the research, it can be concluded that smoked products are a good and safe source of omega-3 fatty acids in the diet.

The objective of the study was to investigate the application of flaxseed oil cake extract (FOCE) for oxidative stabilization of flaxseed oil in spray-dried emulsions. Two variants of powders with 10% and 20% of flaxseed oil (FO), FOCE, and wall material (maltodextrin and starch Capsul^®) were produced by spray-drying process at 180 °C. The oxidative stability of FO was monitored during four weeks of storage at 4 °C by peroxide value (PV) and thiobarbituric acid-reactive substances (TBARS) measurements. Additionally, the fatty acids content (especially changes in α-linolenic acid content), radical scavenging activity, total polyphenolics content, color changes and free amino acids content were evaluated. Obtained results indicated that FOCE could be an adequate antioxidant dedicated for spray-dried emulsions, especially with a high content of FO (20%). These results have important implications for the flaxseed oil encapsulation with natural antioxidant agents obtained from plant-based agro-industrial by product, meeting the goals of circular economy and the idea of zero waste.

Insect farming is more ecological than traditional animal farming, as it requires less water and contributes to lower greenhouse gas emissions. In our study, banded cricket (BC) and mealworm larvae (ML) were analyzed. The proximate composition was determined according to Association of Official Analytical Chemists. The mineral content was determined by colorimetry and mass spectrometry. Fatty acid methyl esters (FAMEs) were obtained from the samples and separated using a gas chromatography apparatus, coupled with a mass spectrometer. Our research confirmed that insects are a rich source of protein, with ML containing significantly more protein than BC (74.41 and 65.66 g/100 g dry matter (DM), respectively). In terms of the content of macrominerals, ML was significantly richer than BC, especially in terms of magnesium content (8.75 g/100 g DM). In terms of the content of saturated fatty acids, BC contained almost twice as much as ML (40.05 and 24.74% of the sum of fatty acids, respectively). EPA and DHA were only detected in the fat of BC. The presented results prove that both ML and BC can be good sources of protein both in human and companion animal diets. The component that is predominantly high in insects is fat, with a favorable fatty acid profile, especially in terms of polyunsaturated fatty acids. This study contributes new knowledge on the nutritional value of edible insects. In this research, we included three different nitrogen conversion factors for crude protein content. Our results partially confirm previous studies by other authors, although they provide new information on the content of fatty acids.