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BACKGROUND: As a result of climate change (reduced the oxygen content and food available in the waters) and overfishing, ever larger batches of the herring catch are classified as low‐value fish and used for feedstuff or canned food production. Fast and complete ripening of marinated fillets, especially from low‐value Baltic herring, poses a problem because of the low muscle protease activity and changes in muscle tissue proteins. RESULTS: For the first time, a crude digestive proteases preparation (CDPP) was obtained from herring viscera using a two‐stage method consisting of ethanol extraction and then salt precipitation. CDPP had a reduced hemoglobin content, with optimum activity at pH 7.5–8.8 or 60–120 g kg−1 NaCl. At pH 4–5, it still exhibited 24–68% of proteolytic activity. CDPP was used for 4–24 h of brining of fresh and frozen–thawed fillets or injection of fresh fillets before marinating. CDPP‐brining increased especially cathepsin D and carboxypeptidase A activities, whereas it decreased cathepsin B and L activities in the marinades. CDPP‐brining mitigated the negative effect of freezing–thawing on mass‐yield, protease activity, protein hydrolysis, texture profile, colour and sensory quality of the marinated fillets. CDPP‐injection was found to be the best method because it increased mass‐yield and ripeness of the marinated fillets to a greater extent than CDPP‐brining did. The marinades from the CDPP‐treated fillets had no bitter taste as a result of the presence of hemoglobin or chymotrypsin, and there were no results indicating lipid oxidation. CONCLUSION: The application of CDPP in marinating technology is a viable approach to enable the use of low‐value herring in food production, shorten the marinating time, and improve the ripeness and sensory quality of meat. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Summary: Cold marinades are produced mainly from the Clupeidae fish, because meat of other fish species does not reach a desired level of ripeness in the acid‐salt environment of fresh brine. Hence, this work presents an innovative idea of reusing brine including cathepsins and peptides for marinating cod, salmon, trout, and carp. The extent of marinades ripening improvement depended on fish resistance to the marinating process. The reused brine proved best in improving the ripening of fatty fish (salmon and trout), which were qualified to the first class of resistance to marinating. In the case of cod, the reuse of brine did not elicit a satisfactory improvement in meat ripening. Therefore cod was qualified to the second class of resistance. The reuse of brine resulted in decreased values of lipid oxidation indices (except for cod) and meat hardness, and in increased scores for overall sensory evaluation and total volatile bases nitrogen value. [ABSTRACT FROM AUTHOR]

The count of Listeria monocytogenes was determined, before and after heat treatment, in 200 samples of dumplings of 9 brands and with different types of stuffing. Analyses were conducted according to ISO 11290-1 standard and with real-time PCR method. The highest count of L. monocytogenes was found in meat dumplings (102 to 104 CFU/g), whereas products with white cheese-potato stuffing and vegetable-mushroom stuffing contained significantly less Listeria, 20 to 80 and 5 to 32 CFU/g, respectively. In cooled meat dumplings the extent of contamination depended significantly on the producer. In addition, a significant ( P < 0.05) correlation was determined between contamination level and meat content in the stuffing (rho = 0.418), especially in stuffing containing pork meat (0.464), contrary to beef-containing stuffing (0.284). Heating dumplings in boiling water for 2 min completely eliminated L. monocytogenes in meat dumplings. In contrast, the microwave heating applied for 2 min at 600 W only reduced the count of L. monocytogenes by 1 to 2 logs. Hence, the microwave heating failed to reduce the risk of infection with this pathogen below the level permissible in the EU regulation, especially in the most contaminated samples. In this case, the efficacy of microwave heating was significantly ( P < 0.05) affected by the initial count of L. monocytogenes (rho = 0.626), then by meat content in the stuffing (0.476), and to the lowest extent-by the type of meat (0.415 to 0.425). However, no Listeria sp. and L. monocytogenes were isolated from cooked dumplings with fruits (strawberries or blueberries). [ABSTRACT FROM AUTHOR]

Fermented milk beverages produced from goat's milk are characterized by loose, soft consistency, which may be improved by the selection of appropriate starter cultures. Taking into account that the starters used in cow's milk technology are not always suitable for goat's milk, the aim of this study was to analyze to what extent two commercially-available yoghurt cultures, with traditional composition, enable obtaining a product with desirable quality properties from goat's milk. Two batches of yoghurt were produced during the experiment. Super jogurt starter of the Canadian Institute Rosell Inc. was used to obtain the first batch (J-A) and Yoghurtferment from Lactoferm (Belgium) for the second batch. The analyzed beverages were subjected to organoleptic, physicochemical and rheological evaluations after 1, 3, 7, 14 and 21 days of refrigerated storage (5 ±1°C). The study demonstrated that fermented milk beverages from goat's milk that was produced with both classic yoghurt cultures had desirable qualitative characteristics. The experimental yoghurts did not differ in the organoleptic properties during storage. The statistically significant differences were noted in the titratable acidity and pH, and not in the viscosity. The produced beverages were characterized by a low content of acetaldehyde, in turn the highest hardness was noted for the J-A beverage produced with the Super jogurt starter. [ABSTRACT FROM AUTHOR]