ZSZofia Sokołowicz

Zofia Sokołowicz

*This is an algorithmically generated author record based on publicly available information.

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Zofia Sokołowicz has a total of 36 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    The Effect of Cyclic Ozonation on the Molecular Stability of Fatty Acids and Cholesterol in Egg Yolk During Storage

    by Maciej Balawejder, Tomasz Piechowiak, Zofia Sokołowicz, Jacek Malec, Radosław Józefczyk, Izabela Szczepanik, Natalia Matłok

    Egg yolks are a valuable source of fatty acids and cholesterol; however, their lipid fraction undergoes natural degradative changes during storage. This study evaluated the effect of cyclic gaseous ozonation (5 ppm for 10 min, applied once weekly) on the fatty acid profile and cholesterol content of hen egg yolk during 5 weeks of storage. Chromatographic analyses (GC-MS) were conducted at weekly intervals (Weeks 0–5). In the control group (without ozonation), storage duration exerted a statistically significant effect on the lipid profile, leading to a progressive decline in the relative proportion of polyunsaturated fatty acids (PUFAs). Specifically, the linoleic acid content decreased from 8.88% to 5.6% by Week 5, while docosahexaenoic acid (DHA) underwent degradation to trace levels. Conversely, the ozonated group showed no statistically significant differences in the relative content of any of the thirteen identified fatty acids over the 5-week period, confirming the relative preservation and stability of the lipid profile. Cholesterol content remained stable (initial value 16.89 mg g−1) and was not significantly altered in either group throughout the storage period. These results indicate that cyclic gaseous ozonation represents an effective approach for preserving the relative stability of the yolk fatty acid profile (including DHA) without adversely affecting cholesterol levels, while the direct evaluation of primary oxidation indices remains a subject for future research.

  • Open Access

    Quality Characteristics of Poultry Products Containing Plant Components with Enhanced Health Benefits

    by Anna Augustyńska-Prejsnar, Małgorzata Ormian, Jadwiga Topczewska, Zofia Sokołowicz, Renata Tobiasz-Salach

    An innovative approach to improving the quality of meat products is to change their recipe composition. The aim of the study was to improve the quality of poultry products with different proportions of plant components. The test groups consisted of paste products: P1—with 50% slaughter turkey meat and 40% plant additives; P2—with 30%, respectively. The control group consisted of classic poultry pâté in paste form. The assessment of paste quality considered the physical characteristics (pH, color), nutritional value (basic chemical composition, fatty acid profile, fiber content, vitamin E, cholesterol, minerals), microbiological quality (total number of aerobic bacteria, Pseudomonas) and sensory quality of the samples. It was found that poultry products containing plant components had increased nutritional value, including reduced fat and cholesterol content, while maintaining a favorable fatty acid profile, increased fiber, vitamin E and mineral content (Mg, Mn, K, Na, Ca, Fe) as well as microbiological safety and acceptable sensory characteristics compared to the control group. Within the research groups, the product from group P2, with a 60% share of plant components, received a higher recommendation with regard to health-promoting properties (higher fiber, Mn, Mg, Na, Ca, Zn content, optimal ratio of omega 6 to omega 3 fatty acids) and sensory characteristics (tastiness, spreadability).


  • Open Access

    Microbial and Sensory Quality Changes in Broiler Chicken Breast Meat During Refrigerated Storage

    by Anna Augustyńska-Prejsnar, Miroslava Kačániová, Paweł Hanus, Zofia Sokołowicz, Mirosław Słowiński

    The aim of the study was to assess the bacterial flora of broiler chicken breast meat using the MALDI method, as well as its sensory evaluation while stored refrigerated at a stable temperature (0.5 °C+/−0.5 °C). Bacterial identification based on peptidic spectra obtained by matrix-assisted laser desorption ionisation time-of-flight (MALDI-TOF MS) mass spectrometry is a rapid, inexpensive, and accurate method for identifying isolates that belong to certain bacterial phyla. The microbiological and sensory quality was assessed on the 1st and 3rd, 5th, 7th, 8th, 9th, 10th, 11th, and 12th day of refrigerated storage. The study identified psychrophilic bacteria to be the dominant microflora during the entire period of refrigerated storage. The species profile of the bacteria, however, varied in the subsequent days of storage. From the 8th day of storage, the profile was dominated by bacteria of the genus Pseudomonas. The proportionate content of Pseudomonas bacteria ranged from 89% on day 8 to 95% on day 11th of storage. The majority of the unfavourable microflora (Aeromonas species, Alcaligenes spp., Klebsiella spp., and Yersinia spp.) were observed on the 11th day of storage, which indicates that meat spoilage processes had commenced. The quality of breast meat from broiler chickens stored at 0.5 °C+/−0.5 °C was sensorially acceptable up to the 8th day of storage.


  • Open Access

    Quality Assessment of Minced Poultry Products Including Black Fermented Garlic

    by Anna Augustyńska-Prejsnar, Miroslava Kačániová, Małgorzata Ormian, Jadwiga Topczewska, Zofia Sokołowicz, Paweł Hanus

    The aim of this study was to evaluate the effect of the addition of fermented black garlic on the quality of minced poultry products. Treatments were organized in four groups (1%, 2%, 3%, and 4%) containing either black fermented garlic (bg) or fresh garlic (fg), and a control (produced without garlic). The quality assessment of minced poultry products included physicochemical properties (weight losses, pH, colour and shear force), microbiological quality (Enterobacteriaceae, total count of bacteria, lactic acid bacteria, and Pseudomonas spp.) and evaluation of sensory attributes. The results showed that the pH values in the black garlic groups, pH 6.06, 6.03, and 6.01, were lower than in the control group, pH 6.16, and tended to decrease during the period of cold storage. As the percentage of black garlic increased, there was a decrease in pH, the value of L* (brightness) from 76.16 in the control group to 48.03 in the group with 4% bg, while the value of b* (yellowing) increased analogously from 12.59 to 16.08. The use of black fermented garlic at 2% as a substitute for fresh garlic is a viable alternative to obtaining product with an acceptable taste and aroma. The addition of 4% black garlic was not acceptable to the assessors.


  • Open Access

    The Effect of Temperature and Storage Duration on the Quality and Attributes of the Breast Meat of Hens after Their Laying Periods

    by Anna Augustyńska-Prejsnar, Paweł Hanus, Małgorzata Ormian, Miroslava Kačániová, Zofia Sokołowicz, Jadwiga Topczewska

    The purpose of this study was to evaluate the effect of temperature (2 °C and 6 °C) and storage duration on the quality and attributes of hens’ breast meat after their laying periods. The study included physicochemical characteristics (pH, drip loss, colour, shear force), microbiological quality (total Enterobacteriaceae family and Pseudomonas count), and sensory quality. Bacterial identification was performed using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. The increased meat pH and drip loss was greater at 6 than 2 °C (p < 0.05). An increase in the tenderness of the meat stored at 6 °C was found as early as day 4, as well as at 2 °C on day 8 of storage (p < 0.05). On day 4 of storage, the meat was characterised by a darker colour than on the first day, but the darkening was greater at 6 °C than at 2 °C (p < 0.05). At 6 °C, on day 4 of storage, there was an increase in yellow saturation (b*) of the meat, which was higher at 6 °C than at 2 °C (p < 0.05). At 2 °C, the total bacterial count and number of Pseudomonas spp. in the meat gradually increased along with increasing storage duration, reaching 4.64 log cfu/g and 4.48 log cfu/g, respectively, on the 8th day of storage. At 6 °C, on the sixth day of storage, the total bacterial count in the meat exceeded 7 log cfu/g, considered the limit of microbiological safety. The meat stored at 2 °C had an acceptable sensory quality until the 8th day of storage. The study shows that storage at 2 °C preserves the sensory characteristics and microbiological safety of the hen meat longer at an acceptable level after the laying period. Extended storage life may be of importance to consumers and the meat industry.


  • Open Access

    Influence of Storage Packaging Type on the Microbiological and Sensory Quality of Free-Range Table Eggs

    by Zofia Sokołowicz, Miroslava Kačániová, Magdalena Dykiel, Anna Augustyńska-Prejsnar, Jadwiga Topczewska

    The studies aimed to assess the impact of packaging, storage time, and temperature on the microbiological quality as well as on the sensory quality and functional properties of chicken eggs. The study material consisted of eggs from laying hens kept under free-range conditions. The eggs packed in cardboard and plastic cartons were stored at 5 °C and 22 °C, respectively. The eggs were examined on the day of laying and on days 14 and 28 of storage. The microbiological quality of the shell and contents of the eggs and the foaming properties of the egg white stored in cardboard and plastic packaging as well as the sensory characteristics of the eggs stored in both types of packaging after hard-boiling were examined on all evaluation dates. The type of packaging in which the eggs were stored was shown to influence the microbiological quality of the egg contents. Eggs stored in plastic packaging, on days 14 and 28 of storage, contained more bacteria in egg contents than eggs stored in cardboard packaging (p < 0.05). The type of packaging in which the eggs were stored did not have an effect on the foaming properties of the egg white (p > 0.05) or on the sensory characteristics of the eggs after hard-boiling. Irrespective of the type of packaging, the foaming properties of the egg white and the sensory characteristics of the eggs after hard-boiling deteriorated with storage time. The effect of temperature on egg quality was found. Regardless of the type of packaging, eggs stored at 5 °C after hard-boiling had better yolk colour, smell, and texture than eggs stored at 22 °C (p < 0.05).


  • Open Access

    Effect of Hen Genotype and Laying Time on Egg Quality and Albumen Lysozyme Content and Activity

    by Józefa Krawczyk, Lidia Lewko, Zofia Sokołowicz, Anna Koseniuk, Adam Kraus

    According to research, egg quality and lysozyme content are influenced by a number of factors, which are mostly known in the case of commercial hybrids, while in breeds included in genetic resources conservation programmes, new research results in this regard are emerging. The aim of the study was to determine the effect of egg laying time and genotype of selected Polish native breeds of hens on egg quality and lysozyme content and activity in the albumen. The study material consisted of eggs collected from four strains of laying hens included in the Polish conservation programme, i.e., Green-legged Partridge (Z-11), Yellow-legged Partridge (Ż-33), Rhode Island Red (R-11) and Leghorn (H-22). At week 56, 28 eggs were randomly collected at 7:00 and 13:00 h from each breed of hen and assessed for quality. Laying time influenced certain egg quality traits. Eggs laid by hens in the morning were characterised by 1.7 g lower total weight and albumen weight, 2.4 pores/cm2 higher number of shell pores, 0.15 higher albumen pH values and 0.17 lower yolk pH values compared to those laid in the morning. The time of laying did not affect the level and activity of lysozyme in the albumen. A significant negative correlation was found between eggshell traits and albumen height, and between Haugh unit and lysozyme content and activity in the albumen. The studied egg quality traits were more influenced by genotype than by the egg-laying time.


  • Open Access

    Quality and Microbiological Safety of Poultry Meat Marinated with the Use of Apple and Lemon Juice

    by Anna Augustyńska-Prejsnar, Miroslava Kačániová, Małgorzata Ormian, Jadwiga Topczewska, Zofia Sokołowicz

    The aim of the study was to evaluate the use of apple juice for the marinating of poultry meat and its effect on the technological as well as sensory characteristics and microbiological safety of the raw product after heat treatment. Broiler chicken breast muscles were marinated for 12 h in apple juice (n = 30), a mixture of apple and lemon juice (n = 30) and compared with those in lemon juice (n = 30). The control group (n = 30) consisted of unmarinated breast muscles. Following the evaluation of the technological parameters (pH, L*, a*, b* colour, cutting force, cooking losses) quantitative and qualitative microbiological evaluations were performed on the raw and roasted products. The microbiological parameters were determined as total Mesophilic aerobic microorganisms, Enterobacteriaceae family, and Pseudomonas count. The bacterial identification was performed using a matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. The marinating resulted in lower pH value, but increased tenderness of raw and roasted products. Marinating chicken meat in both apple and lemon juices, including their mixtures and in the control sample, resulted in increased yellow saturation (b*). The highest flavour desirability and overall desirability were obtained in products marinated using a mixture of apple and lemon juice, while the most desirable aroma was obtained from products marinated with apple juice. A significant antimicrobial effect was observed in marinated meat products compared to unmarinated, irrespective of the type of marinade used. The lowest microbial reduction was observed in the roasted products. Apple juice can be used as a meat marinade because it promotes interesting sensory properties and improves the microbiological stability of poultry meat while maintaining the product’s good technological characteristics. It makes a good combination with the addition of lemon juice.


  • Open Access

    A Comparison of the Plumage Condition of Three Egg-Laying Poultry Genotypes Housed in Non-Cage Systems

    by Zofia Sokołowicz, Magdalena Dykiel, Jadwiga Topczewska, Józefa Krawczyk, Anna Augustyńska-Prejsnar

    The study covered a total of 810 hens in 3 groups (housing systems) of 270 hens each. The plumage condition of laying hens raised in various types of alternative housing systems, i.e., in deep litter (B), free-range (FR), and organic systems (O), was assessed at 20, 36, and 56 weeks of age. The indoor stocking density was 6 hens/m2. The study included hens of the native Green-legged Partridge breed (Z-11), Rhode Island Red (R-11) hens covered by a genetic resource protection program, and hybrids of Hy-Line Brown. The plumage of the head, neck, back, tail, and abdomen was assessed on a 5-point scale. The assessment of individual hens' plumage was calculated as the sum of the scores of the head, neck, back, tail and abdomen and could range from 0 (no cover) to 20 points (full plumage). The type of alternative housing system implemented and the age of the laying hens had an effect on the plumage status of all body parts assessed (p < 0.05), while the genotype had an effect on the condition of the neck, back, and tail plumage (p < 0.05). In both the FR and O systems, the plumage status was similar and superior to that in B (p < 0.05). As the age of the birds increased, the condition of the hens' plumage deteriorated. The better state of the plumage in FR and O than in B may indicate improved levels of welfare in housing systems with access to outside runs.


  • Open Access

    Quality of Poultry Roast Enriched with Hemp Seeds, Hemp Oil, and Hemp Flour

    by Anna Augustyńska-Prejsnar, Jadwiga Topczewska, Małgorzata Ormian, Zofia Sokołowicz

    The aim of this study was to add natural hemp components to poultry roast recipes, to enhance their quality (physical, chemical, and sensory qualities of the product). Two variants of poultry roast (group P1 and P2) with a 10.2% addition of hemp components and a traditional equivalent with the participation of animal fat (group K) were tested. In the roast of group P1, the share of hemp seeds was 8%, hemp flour 0.2%, and hemp oil 2%; while in group P2, the proportions were 4%, 0.2%, and 6%, respectively. Roasts with hemp components were found to be characterized by a darker color; lower cooking losses; higher fiber content, and lower cholesterol and fat content; a favorable fatty acid ratio PUFA; n-3 and n-6; and acceptable sensory characteristics compared to the control group. Products with a higher (8%) share of hemp seeds contained more protein and fiber and were characterized by a higher degree of yellow saturation (b*), lower cooking losses after heat treatment, and a higher desirability of taste and better binding. Products in group P2, with a higher (6%) hemp oil content, had a lower cholesterol content and a lower proportion of SFA fatty acids and a higher proportion of omega-3 fatty acids, but were assessed as rated lower in terms of taste and binding.