Barium hexaferrite powder samples with grains in the μm-range were obtained from solid-state sintering, and crystals with sizes up to 5 mm grown from PbO, Na2CO3, and BaB2O4 fluxes, respectively. Carbonate and borate fluxes provide the largest and structurally best crystals at significantly lower growth temperatures of 1533 K compared to flux-free synthesis (1623 K). The maximum synthesis temperature can be further reduced by the application of PbO-containing fluxes (down to 1223 K upon use of 80 at % PbO), however, Pb-substituted crystals Ba1–xPbxFe12O19 with Pb contents in the range of 0.23(2) ≤ x ≤ 0.80(2) form, depending on growth temperature and flux PbO content. The degree of Pb-substitution has only a minor influence on unit cell and magnetic parameters, although the values for Curie temperature, saturation magnetization, as well as the coercivity of these samples are significantly reduced in comparison with those from samples obtained from the other fluxes. Due to the lowest level of impurities, the samples from carbonate flux show superior quality compared to materials obtained using other methods.
Alginate is widely used in the food industry due to its biodegradability, biocompatibility, and non-toxicity. Protein hydrolysates possess properties important for forming the mechanical characteristics, protective, and barrier properties of the films. The aim of the research was to develop biodegradable alginate-based films with bioactive properties and the optimal structural characteristics when protein hydrolysates were incorporated. The microstructure of the cross-sections of films with 0.5 and 1.0% protein hydrolysates was characterized by smoother and homogeneous surfaces, which indicated the compatibility of sodium alginate and protein hydrolysate. The addition of protein hydrolysate significantly increased the thickness of the film by 0.06 mm and reduced the solubility by 49.4% (p < 0.05). The results showed the high biodegradability of alginate-based films after 2 weeks of storage. With the introduction of protein hydrolysate, changes occurred in the FTIR patterns due to the interaction between the hydroxyl groups of peptides and the alginate, and, consequently, the thermal stability of the alginate films increased. The alginate films with PH positively affected the storage capacity of sweet cherry berries, both at room temperature and under refrigeration conditions. The alginate-based films with protein hydrolysate have improved properties and can serve as an alternative to polypropylene packaging materials.
Fermentation is an economical method for obtaining protein hydrolysates. The purpose of the scientific research was to perform a comprehensive analysis of the physicochemical, technological, and functional properties of protein hydrolysates obtained by microbial fermentation. The research results showed that hydrolysates fermented with propionic acid bacteria and bifidobacteria have better physicochemical and technological indicators compared to the control sample. Significant increases in water-holding and fat-holding capacities (by 1.8–2.1 times and 1.5–2.5 times, respectively), as well as fat-emulsifying ability (by 12.8–29.8%) in experimental samples were found. Hydrolysates obtained by fermentation effectively inhibit the growth of Escherichia coli and Staphylococcus aureus. The thermal analysis showed a sufficiently high-thermal stability of the obtained protein hydrolysates. In hydrolysates fermented by bacterial culture, the removal of physico-mechanical and osmotically bound moisture occurred at temperatures of 110 °C and 115 °C, respectively, and in whey protein hydrolysate at a temperature of 100 °C. The release of chemically bound moisture was observed at a temperature of 170 °C for fermented hydrolysates and at 155 °C for the control sample. The results proved that fermented protein products are characterized by high functional properties, antioxidant and antimicrobial activity, and can be used as natural food additives and preservatives.
In connection with the active growth of poultry processing, the issue of rational use of poultry by-products is urgent. The paper proposes hydrolysis of the gizzards of broiler chickens and hens of the parent stock with bifidobacteria liquid concentrate (BLC) and Propionix liquid concentrated starter culture (Propionix LCSC). The effect of enzymatic treatment on changes in the structural components of the gizzards was studied using scanning electron microscopy (SEM) and determination of the dispersed composition. As a result of the research, the multiple regression equations and the response surfaces were obtained, which describe the optimal parameters of the gizzard´s hydrolysis process. The temperature and the time of hydrolysis are factors that have a significant effect on the degree of hydrolysis. The results of the structural and microscopic analysis confirm the high hydrolysability of the by-products by changing its structure and increasing the number of smaller protein particles. It was found experimentally that the gizzards of hens are more susceptible to the action of probiotic microorganisms’ enzymes compared to the gizzards of broiler chickens.
About Me
A researcher of the Scientific and Educational Center of Nanotechnology. Research interests are materials and technology.
A researcher of the Scientific and Educational Center of Nanotechnology. Research interests are materials and technology.