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Analysis of Changes in the Amount of Phytosterols after the Bleaching Process of Hemp Oils

2022, Kwaśnica, Andrzej, Teleszko, Mirosława, Marcinkowski, Damian, Kmiecik, Dominik, Grygier, Anna, Golimowski, Wojciech

Unrefined vegetable oils from niche oilseeds are now sought after by consumers because of their unique nutritional properties and taste qualities. The color and flavor intensity of niche oils is a big problem, and their refining is not industrially feasible due to the small production scale. The study undertaken aimed analyze the effect of changing the amount of phytosterols (PSs) after the bleaching process of hemp oils of the ‘Finola’, ‘Earlina 8FC’ and ‘Secuieni Jubileu’ varieties. Cold-pressed (C) and hot-pressed (H) crude vegetable oils were bleached with selected bleaching earth (BE) at two concentrations. The post-process BE was extracted with methanol. The amount of PSs in the crude oils and the extract after washing the BE with methanol was analyzed by GC (gas chromatography). The study shows that the bleaching process did not significantly affect the depletion of PSs in the oils. Trace amounts of PSs remain on the BE and, due to methanol extraction, can be extracted from the oil. The conclusion of the performed research is that the bleaching of hemp oil does not cause depletion of the oil, and it significantly improves organoleptic properties. The oil bleaching process results in an oil loss of less than 2% by weight of the bleached oil, while the loss depends on the type of BE used. The study shows that the loss of phytosterols after the bleaching process averages 2.69 ± 0.69%, and depends on the type of BE used and the oil extracted from different varieties of hemp seeds.

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Sposób wytwarzania chleba mieszanego z leżakowanymi liśćmi morwy białej, w szczególności dla diabetyków

2023, Przeor, Monika Teresa, Kobus-Cisowska, Joanna Magdalena, Kmiecik, Dominik, Szczepaniak, Oskar, Beszterda-Buszczak, Monika Krystyna

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Liposomes as Carriers of Bioactive Compounds in Human Nutrition

2024, Rudzińska, Magdalena, Grygier, Anna, Knight, Geoffrey, Kmiecik, Dominik

This article provides an overview of the literature data on the role of liposomal structures and encapsulated substances in food technology and human nutrition. The paper briefly describes how liposomes are created and how they encapsulate food ingredients, which can either be individual compounds or plant extracts. Another very interesting application of liposomes is their use as antimicrobial carriers to protect food products from spoilage during storage. The encapsulation of food ingredients in liposomes can increase their bioavailability, which is particularly important for compounds with health-promoting properties but low bioavailability. Particular attention was paid to compounds such as phytosterols, which lower blood cholesterol levels but have very low absorption in the human body. In addition, consumer expectations and regulations for liposomes in food are discussed. To date, no in vivo human studies have been conducted to indicate which encapsulation methods give the best results for gastrointestinal effects and which food-added substances are most stable during food storage and processing. The paper identifies further lines of research that are needed before liposomes can be introduced into food.

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Heating and storage of structured acylglycerols with succinyl-linked stigmasterol residue does not cause negative chemical or biological changes

2023, Rudzińska, Magdalena, Grygier, Anna, Olejnik, Anna, Kowalska, Katarzyna, Kmiecik, Dominik, Chojnacka, A., Gładkowski, W., Grudniewska, A., Przybylski, R.

AbstractFour structured acylglycerols with stigmasterol bonded by a succinyl linker were investigated and their stability were analyzed. Samples were heated to 60 °C and kept at that temperature to simulate storage, and to 180 °C to simulate frying conditions. The degradation of the synthesized compounds and formed derivatives was determined, and their cytotoxicity and genotoxicity on normal human cells from the digestive system was determined. Holding at 180 °C resulted in greater degradation of the compounds than holding at 60 °C. The most stable compound in each sample proved to be one with oleic acid in its structure—1,3-dioleoyl-2-stigmasterylsuccinoyl-sn-glycerol (DO2SSt) at 60 °C and 1,2-dioleoyl-3-stigmasterylsuccinoyl-sn-glycerol (DO3SSt) at 180 °C. These results indicate that the type of fatty acid in the molecule is more important than its position in the glycerol structure. None of the diacylmonostigmasterylsuccinoyl-sn-glycerols (DASStGs) before or after heating exhibited cytotoxic or genotoxic potential to small intestine and colon mucosa cells.

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Comparative analysis of nutritional composition and bioactive properties of Chlorella vulgaris and Arthrospira platensis: Implications for functional foods and dietary supplements

2025, Čmiková, Natália, Kowalczewski, Przemysław Łukasz, Kmiecik, Dominik, Klimowicz, Piotr, Drożdżyńska, Agnieszka, Ślachciński, Mariusz, Królak, Jakub, Matić, Sanja, Marković, Tijana, Popović, Suzana, Baskic, Dejan, Kačániová, Miroslava

Abstract The rising incidence of chronic diseases has spurred interest in functional foods rich in antioxidants and essential nutrients, as well as in exploring their potential cytotoxic activity against cancer cells. This study aims to address this gap by providing a comprehensive comparison of their biochemical composition and bioactive properties, offering insights into their targeted applications in functional foods and supplements. This study investigated the nutritional composition and bioactive properties of two algae species, chlorella (Chlorella vulgaris) and spirulina (Arthrospira platensis). Analysis included total protein content, amino acid profiles, mineral compositions, fatty acid profiles, B vitamin contents, polyphenol profiles, carotenoid contents, antioxidant activities (DPPH˙ and ABTS+ assays), and cytotoxic activities. Chlorella exhibited higher protein content (64.63%) compared to spirulina (58.24%). Spirulina showed higher concentrations of non-essential and essential amino acids, except for methionine. Mineral analysis revealed spirulina’s superiority in calcium, potassium, sodium, iron, manganese, and zinc, whereas chlorella contained higher copper and lead levels. Fatty acid analysis indicated chlorella’s dominance in saturated fatty acids, while spirulina showed higher proportions of monounsaturated and polyunsaturated fatty acids. Polyphenol analysis highlighted chlorella’s higher levels of p-hydroxybenzoic acid, whereas spirulina contained more rutin and catechin. Chlorella also exhibited higher levels of niacin and riboflavin compared to spirulina. Additionally, spirulina extracts, whether ethanolic or hexane-based, demonstrate substantial antioxidant effects, as evidenced by their lower IC50 values in both DPPH˙ and ABTS+ assays relative to chlorella. Overall, spirulina showed superior antioxidant effect. Chlorella hexane extract showed slightly higher cytotoxic potential compared to spirulina. These findings enhance our understanding of the nutritional and health-promoting properties of chlorella and spirulina, suggesting their potential applications in functional foods and dietary supplements. While in vitro assays indicate promising bioactivity, future studies should include in vivo experiments to confirm the health benefits and functional applications of these microalgae.

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The Stability of Refined Rapeseed Oil Fortified by Cold-Pressed and Essential Black Cumin Oils under a Heating Treatment

2022, Fedko, Monika, Kmiecik, Dominik, Siger, Aleksander, Majcher, Małgorzata Anna

Polar compounds and polymers are regarded as the most reliable indicators of oil degradation during heating, and it is desirable to find methods to reduce these undesirable changes. The aim of this study was (1) to determine the effect of enrichment with black cumin cold-pressed oil (CP) or essential oil obtained from black cumin cold-pressed oil in an equivalent amount (ES) on limiting the polar compounds and polymers content in blends based on refined rapeseed oil during high-temperature heating in a thin layer; (2) to determine tocochromanol losses and their effect on the change content of the polar compounds and polymers. Four fortified oils were made from refined rapeseed oil and one of the four additives (10% CP, 20% CP, 0.1% ES, and 0.2% ES). All fortified oils and refined rapeseed oil as a control sample were heated at 170 and 200 °C on the pan in a thin layer and evaluated regarding loss of individual tocochromanol homologs by HPLC-FL, polar compounds content, oxidized triacylglycerols (TAG), and polymers content by HPSEC-ELSD. Additionally, the fatty acid profile in nonheated oil was investigated. Tocochromanol analysis showed loss in all the samples. At 170 °C polymers were not detected; no difference was noted for polar compounds and oxidized TAG content; only the 20% CP sample showed a higher level. At 200 °C the 10% CP sample exhibited a significant protective effect with the lowest content of polar compounds, oxidized TAG, and dimers.

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Fermenting of flaxseed cake with Lactiplantibacillus plantarum K06 to increase its application as food ingredient - The effect on changes in protein and phenolic profiles, cyanogenic glycoside degradation, and functional properties

2025, Waszkowiak, Katarzyna, Makowska, Agnieszka, Mikołajczak, Beata, Myszka, Kamila, Barthet, Véronique J., Zielińska-Dawidziak, Magdalena, Kmiecik, Dominik, Truszkowska, Michalina

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Black Cumin Essential Oil as an Active Stabilization Component of Rapeseed Oil During Deep-Fat Model Heating

2025, Kmiecik, Dominik, Siger, Aleksander, Kuraszyk, Katarzyna

The aim of this study was to evaluate the potential of black cumin essential oils to reduce the degradation of rapeseed oil during heating. Rapeseed oil was heated without addition and with the addition of black cumin essential oil (200 ppm, 500 ppm, and 1000 ppm), and with synthetic antioxidant TBHQ (200 ppm). The heating was carried out at 170 °C ± 10 °C for 6 h, in a deep-fat heating model. In all samples, changes in fatty acid profile, lipid-nutritional quality indices (PUFA/SFA ratio, atherogenicity index, thrombogenicity index, and hypocholesterolemic/hypercholesterolemic ratio), tocopherol and phytosterol content, total polar compound content, and triacylglycerol polymers were determined. The heating process led to oil degradation, which depended on the amount and type of additive used. The greatest changes were observed in the control sample (without additives). The addition of TBHQ or 200 ppm of black cumin essential oil reduced the adverse transformations to a similar level. Higher additions of black cumin essential oil led to a significant improvement in the quality of heated oils. The best results were obtained with the addition of 1000 ppm of black cumin essential oil.

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Changes in Oil Quality and Peroxidase Activity during Germination of Rape Seeds and Mustard Seeds

2023, Belt, Dorota, Grygier, Anna, Siger, Aleksander, Kmiecik, Dominik, Spasibionek, Stanisław, Rudzińska, Magdalena

Vegetable oils are selected by consumers based on the presence of multiple bioactive substances, including polyunsaturated fatty acids, sterols, and tocopherols. Another important factor in oils is their quality. This research involved analyzing the oils quality and quantity of bioactive substances obtained from rape seeds and white mustard seeds that underwent germination. The quality of the oils was compared by determining the acid and peroxide values. Germination lowered the peroxide value by 86.3% and 71.4% for rapeseed oil and mustard oil, respectively. This was due to the germination step of the seed use oxygen, which was the substrate for lipid peroxidation. The activity of peroxidase increased by 95% for rapeseed oil and 94% for mustard oil during germination. An increase in the amount of polyunsaturated fatty acids in mustard oil also was noted during germination.

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Effect of Heating Temperature of High-Quality Arbequina, Picual, Manzanilla and Cornicabra Olive Oils on Changes in Nutritional Indices of Lipid, Tocopherol Content and Triacylglycerol Polymerization Process

2023, Kmiecik, Dominik, Fedko, Monika, Małecka, Justyna, Siger, Aleksander, Kowalczewski, Przemysław

The aim of the study was to determine the stability and heat resistance of extra premium olive oil. The study material consisted of six extra virgin olive oils (EVOO) obtained from Spain. Four samples were single-strain olive oils: Arbequina, Picual, Manzanilla, and Cornicabra. Two samples were a coupage of Arbequina and Picual varieties: Armonia (70% Arbequina and 30% Picual) and Sensation (70% Picual and 30% Arbequina). Olive oil samples were heated at 170 °C and 200 °C in a pan (thin layer model). In all samples, changes in indexes of lipid nutritional quality (PUFA/SFA, index of atherogenicity, index of thrombogenicity, and hypocholesterolemic/hypercholesterolemic ratio), changes in tocopherol, total polar compounds content, and triacylglycerol polymers were determined. Heating olive oil in a thin layer led to its degradation and depended on the temperature and the type of olive oil. Increasing the temperature from 170 to 200 °C resulted in significantly higher degradation of olive oil. At 200 °C, deterioration of lipid nutritional indices, total tocopherol degradation, and formation of triacylglycerol polymers were observed. A twofold increase in the polar fraction was also observed compared to samples heated at 170 °C. The most stable olive oils were Cornicabra and Picual.

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Analysis of Quality Distinctions of Pumpkin Seed Oil (Cucurbita pepo var. oleifera) and Walnut Oil (Juglans regia L.)

2026, Czwartkowski, Kamil, Nizio, Edyta, Marcinkowski, Damian, Kmiecik, Dominik, Grygier, Anna, Siger, Aleksander, Golimowski, Wojciech

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Volatile compounds formed during heating of asymmetric distigmasterol-modified acylglycerols as indicators of thermo-oxidative degradation

2025, Grygier, Anna, Rudzińska, Magdalena, Kmiecik, Dominik, Grudniewska, Aleksandra

Abstract Phytosterols play a significant role for organisms. They are a component of cell membranes and also have transport functions. They are also important for lower human blood cholesterol levels. The asymmetric distigmasterol-modified acylglycerols (DStA) with oleic and palmitic acid were synthesized as new, more stable derivatives than free phytosterols. The new structure can improve phytosterols solubility in oil. The identification of more stable forms of phytosterols will allow their greater use as a food additive. Assessment of the volatile compounds formed during thermo-oxidative degradation of phytosterols (60 °C and 180 °C), which may affect the flavor of food products, is a rapid and sensitive method for evaluating phytosterol degradation. The GC/MS technique was used for the determination of volatile compounds. The aim of this work was to determine the volatiles formed during storage and thermal degradation of DStA in order to develop a rapid and sensitive system of measuring their degradation. The same compounds were identified for free stigmasterol, its esters with fatty acids, and new DStAs. Eight volatile compounds can act as indicators of sterol degradation during storage and heating. The synthesized 2,3-distigmasterylsuccinoyl-1-oleoyl-sn-glycerol (DStS-O) offered the highest thermo-oxidative stability during storage and thermal processing of all the examined acylglycerols.

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The Effect of High-Temperature Heating on Amounts of Bioactive Compounds and Antiradical Properties of Refined Rapeseed Oil Blended with Rapeseed, Coriander and Apricot Cold-Pressed Oils

2024, Fedko, Monika, Siger, Aleksander, Szydłowska-Czerniak, Aleksandra, Rabiej-Kozioł, Dobrochna, Tymczewska, Alicja, Włodarczyk, Katarzyna, Kmiecik, Dominik

Cold-pressed oils are rich sources of bioactive substances, which may protect triacylglycerols from degradation during frying. Nevertheless, these substances may decompose under high temperature. This work considers the content of bioactive substances in blends and their changes during high-temperature heating. Blends of refined rapeseed oil with 5% or 25% in one of three cold-pressed oils (rapeseed, coriander and apricot) were heated at 170 or 200 °C in a thin layer on a pan. All non-heated blends and cold-pressed oils were tested for fatty acid profile, content and composition of phytosterols, tocochromanols, chlorophyll and radical scavenging activity (RSA) analyzed by 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays. Moreover, the stability of phytosterols, tocochromanols, DPPH and ABTS values was determined in heated blends. All tocochromanols were lost during the heating process, in particular, at 200 °C. However, there were some differences between homologues. α-Tocopherol and δ-tocopherol were the most thermolabile and the most stable, respectively. Phytosterols were characterized by very high stability at both temperatures. We observed relationships between ABTS and DPPH values and contents of total tocochromanols and α-tocopherol. The obtained results may be useful in designing a new type of fried food with improved health properties and it may be the basis for further research on this topic.

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Fabrication and characterization of novel β-sitosterol-loaded O/W Pickering emulsions stabilized by edible insects protein/chitosan complex coacervates: Retention and stability evaluation

2025, Pokorski, Patryk, Strojny - Cieślak, Barbara, Domian, Ewa, Załęcki, Michał, Grygier, Anna, Pruchniewski, Michał, Zakrzewska, Anna, Aktaş, Havva, Aljewicz, Marek, Kmiecik, Dominik, Custodio - Mendoza, Jorge A., Boruszewski, Piotr, Kurek, Marcin A.

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Analysis of phytosterols encapsulated in pegylated liposomes

2025, Igielska-Kalwat, Joanna, Rudzińska, Magdalena, Grygier, Anna, Kmiecik, Dominik, Cieślik-Boczula, Katarzyna, Dwiecki, Krzysztof, Smułek, Wojciech

Abstract Dipalmitoylphosphatidylcholine (DPPC) lipids were encapsulated in PEGylated liposomes with free stigmasterol (ST), stigmasterol myristate (ME), and stigmasterol oleate (OE). Their quality was assessed using TEM, zeta potential, and hydrodynamic diameter measurements. The liposomes were heated to 60 °C and 180 °C. The degradation of stigmasterol and fatty acids was considered, as was derivative formation. The results show that the liposomes fulfilled their intended function. The ST liposomes were smallest, while the ME liposomes were similar in size to the OE liposomes. The degree of degradation of the compounds encapsulated in the liposomes depended on their structure. After heating the samples to 60 °C, the extent of stigmasterol degradation ranged from 3.5% in ST to 4.3% in ME and 6.5% in OE. After heating to 180 °C, the lowest level of stigmasterol degradation was observed for OE (7.3%), while degradation in ST and ME reached 13.4% and 10.1%, respectively. The high level of oxyphytosterols in all samples heated to 180 °C raised concerns. The oxyphytosterol (SOP) content of the liposomes heated to 60 °C ranged from 23.2 mg/g in those with free stigmasterol to 6.3 mg/g and 6.4 mg/g in the liposomes with stigmasterol myristate and stigmasterol oleate, respectively. After heating to 180 °C, the total SOP content was significantly higher, ranging from 88.7 mg/g for OE to 7.4 and 29.6 mg/g for ME and ST, respectively.

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Characterization of Selected Microalgae Species as Potential Sources of Nutrients and Antioxidants

2024, Čmiková, Natália, Kowalczewski, Przemysław Łukasz, Kmiecik, Dominik, Tomczak, Aneta, Drożdżyńska, Agnieszka, Ślachciński, Mariusz, Królak, Jakub, Kačániová, Miroslava

Microalgae are exceptional organisms from a nutritional perspective, boasting an array of bioactive compounds that have long justified their incorporation into human diets. In this study, we explored the potential of five microalgae species: Nannochloropsis sp., Tetraselmis chuii, Chaetoceros muelleri, Thalassiosira weissflogii, and Tisochrysis lutea. We conducted comprehensive analyses of their nutritional profiles, encompassing protein content, individual amino acid composition, mineral and trace element levels, fatty acid profiles (including saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs)), polyphenol compositions, and vitamin B content. The antioxidant activity of the ethanolic extracts was evaluated using two methods: ABTS and DPPH radical scavenging assay. The total protein content of the microalgae ranged from 34.09 ± 0.39% to 42.45 ± 0.18%, with the highest concentration observed in T. weissflogii. Essential amino acids such as histidine, threonine, lysine, valine, isoleucine, leucine, phenylalanine, and methionine were present in concentrations ranging from 0.53 ± 0.02 to 12.55 ± 2.21 g/16 g N. Glutamic acid emerged as the most abundant amino acid, with concentrations ranging from 6.73 ± 0.82 to 12.55 ± 2.21 g/16 g N. Among the microalgae species, T. chuii exhibited the highest concentrations of calcium (Ca) and manganese (Mn), while C. muelleri showed prominence in magnesium (Mg), sodium (Na), and iron (Fe). T. weissflogii stood out for its potassium (K) content, and T. lutea contained notable amounts of copper (Cu), zinc (Zn), and lead (Pb). Regarding fatty acid profiles, Nannochloropsis sp. and T. chuii were predominantly composed of SFA, while C. muelleri and T. weissflogii were rich in MUFA. PUFAs dominated the fatty acid profile of T. lutea, which also exhibited the most diverse range of polyphenolic substances. We also analyzed the B vitamin content, with T. lutea displaying the highest concentrations of niacin (B3) and riboflavin (B2). Antioxidant activity was confirmed for all microalgae tested using DPPH and ABTS radical IC50 (mg/mL) converted to Trolox equivalent (TEAC). These findings underscore the substantial potential of the examined microalgae species as sources of biologically valuable substances characterized by rapid growth and relatively undemanding cultivation conditions.

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Effect of gastrointestinal digestion on the stability and cytotoxicity of conventional and pegylated liposomes encapsulated with stigmasterol and its esters

2025, Rudzińska, Magdalena, Grygier, Anna, Olejnik, Anna, Kowalska, Katarzyna, Igielska-Kalwat, Joanna, Kmiecik, Dominik, Cieślik-Boczula, Katarzyna

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Thermo-oxidative stability and safety of new acylglycerols with stigmasterol residue: Effects of fatty acids saturation and position in the glycerol backbone

2023, Rudzińska, Magdalena, Olejnik, Anna, Grygier, Anna, Kowalska, Katarzyna, Kmiecik, Dominik, Chojnacka, A., Gładkowski, W., Grudniewska, A., Przybylski, R.

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Improvement of Refined Rapeseed Oil Thermal Resistance by Native Antioxidants Present in Rapeseed, Coriander, and Apricot Cold-Pressed Oils

2026, Fedko, Monika, Siger, Aleksander, Kmiecik, Dominik

The research aimed to evaluate the effect of high monounsaturated cold-pressed oil addition on the inhibition of refined rapeseed oil degradation during heating at frying temperature. Cold-pressed rapeseed, coriander seed, and apricot kernel oils were added in amounts of 5 and 25%. Refined rapeseed oil without additives and refined rapeseed oil supplemented with tert-butylhydroquinone (TBHQ) were negative and positive control samples, respectively. Blends were heated in a thin layer at 170 and 200 °C. Considering the increase in total polar compounds (TPCs) and oxidized triacylglycerol monomer (oxTAG) content, natural additives demonstrated protective properties and were more effective than the TBHQ additive, especially at 200 °C. The lowest increases in TPC and oxTAG were found in AO5% at 170 °C (10.17% and 1.40 mg/g oil, respectively) and in AO25% at 200 °C (5.71% and 47.53 mg/g oil, respectively). The presence of triacylglycerol (TAG) dimers was found only in samples heated at 200 °C, and the lowest was in the sample with 25% coriander oil. It can be concluded that the addition of cold-pressed oils limited the TAG oxidation process. The addition of 25% coriander oil was effective in inhibiting the TAG polymerization process, and it may be a powerful alternative to synthetic antioxidants in improving stabilization of frying oils.

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Higher Oxygen Content Affects Rabbit Meat’s Quality and Fatty Acid Profile in a Modified Atmosphere

2024, Składanowska-Baryza, Joanna, Kmiecik, Dominik, Rudzińska, Magdalena, Vissio, Annalisa, Grygier, Anna, Ludwiczak, Agnieszka, Stanisz, Marek

After 7 days of storage, the quality of the meat packed in both systems (MAP and VAC) was satisfactory; however, after 14 and 21 days, there was a noticeable decline in quality, as evidenced by changes in the water percentage and color parameters (L∗, a∗, and b∗). However, muscles stored in the MAP1 had the highest tenderness. The results indicated that as the storage time increased (up to 21 days), the share of C14:0 (P<0.001) and C16:0 (P<0.001) acids in the fat of the LTL muscles decreased. Only the share of C18:0 (P=0.001) and C20:1 (P=0.015) acids was significantly influenced by the packaging method. The highest iodine level was found in MAP1 21 days after packaging (85.68). The ratio of n-6/n-3, PUFA/SFA, AI, and TI indexes, which indicate a higher nutritional quality of fat, varied only with storage time without being affected by the gas mixture (P>0.05). The H/H level differed significantly with the storage time (P<0.001), with no effect of the gas mixture (P=0.133). After the 21-day storage period, the controlled atmosphere led to an increase in the concentration of MUFA and PUFA and a decrease in SFA, according to the study of the fatty acid profile.