Sous-vide is a process in which food is vacuum-sealed and prepared in a water bath, heated to a precise temperature, and circulated in a sous-vide machine. This cooking technique is increasingly common in homes and catering establishments due to its simplicity and affordability. However, manufacturers' and chefs' recommendations for low-temperature and long-term sous-vide cooking in media raise food safety concerns, particularly when preparing beef tenderloin. In this study, Salmonella enterica was found to be inactivated by heat and sage essential oil (EO) in beef tenderloin from musculus psoas major that had undergone sous-vide processing. To determine whether heat treatment was likely to increase the sous-vide efficiency, S. enterica and sage EO were mixed. After being vacuum-packed and injected with S. enterica, the samples were cooked sous-vide for the prescribed time at 50, 55, 60, or 65 °C. On days 1, 3, and 6, the amounts of S. enterica, total bacteria, and coliform bacteria were measured in both groups of sous vide beef tenderloin. Mass spectrometry was used to identify bacterial strains on various days and categories. Each day that was measured, the test group exposed to a temperature of 50 °C for 5 minutes had a higher number of all microbiota. The most isolated microorganisms from the control and treated groups were Pseudomonas fragi, and in the treated group also S. enterica. It has been shown that adding sage essence oil (EO) in combination with the sous-vide gastronomic method leads to the stabilization and safety of beef tenderloin.

Chicken collagen is a promising raw material source to produce gelatins and hydrolysates. Gelatins and hydrolysates can be prepared biotechnologically using proteolytic enzymes produced by submerged fermentation of genetically modified microorganisms. By choosing the appropriate process conditions, such changes can be achieved at the molecular level of collagen, making it possible to prepare products with targeted properties for advanced cosmetic, pharmaceutical, medical or food applications. The research aims to investigate: i) antioxidant activity (DPPH and ABTS) in model samples of chicken collagen products (gelatin and hydrolysates); ii) distribution of molecular weights by the GPC-RID analysis method; iii) functional groups and configuration of polypeptide chains related to molecular level properties using FTIR; iv) the microbiological properties on SDA, PCA, TSA and VRBL microbial populations using MALDI method. Antioxidant activity towards ABTS radicals of more than 80% was found for all samples. The molecular weights of all gelatin samples showed typical α- and β-chains. FTIR analysis confirmed that the samples showed all typical vibrational regions for collagen cleavage products, Amide A and B, Amide I, II, and III at characteristic values. Microbiological analysis of the prepared samples showed no undesirable bacteria that would limit advanced applications of the prepared products. Gelatins and hydrolysates from chicken stomachs represent a promising alternative to products made from standard collagen tissues of terrestrial animals.

Gelatin fibers have a specific surface and high porosity, which is why their use in medicine and the food industry is being researched. This article explores the potential of centrifugal spinning to produce gelatin fibers. Gelatin for fiber preparation is obtained from a non-traditional source of collagen (chicken by-products) using a unique enzymatic process. The fiber quality is compared with those prepared from traditional collagen tissues (porcine, bovine). The results show that fibers crosslinked with glutaraldehyde vapor preserve their structure even in contact with water. Using a cross-linker controls swelling ability and solubility while maintaining the fiber structure. On the contrary, uncross-linked gelatin fibers are water soluble due to a high surface-to-volume ratio, facilitating water penetration and dissolution. Scanning electron microscopy (SEM) provided a clearer picture of the morphology of gelatin fibers obtained by centrifugal spinning. Differences in the amount of bonding depending on the raw material used and the presence of cross-linker were analyzed using Fourier transform infrared spectroscopy (FTIR). The overall results showed that chicken gelatin is a suitable alternative to gelatins from traditional sources.