Katarzyna Król

Ms. Katarzyna Król

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 November 2019 in European Food Research and Technology
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Journal Article
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KKKatarzyna Król
Katarzyna Król
MGMagdalena Gantner
Magdalena Gantner
ATAleksandra Tatarak
Aleksandra Tatarak
EHEwelina Hallmann
Ewelina Hallmann
Coffee, one of the most popular beverages in the world, contains many bioactive compounds. The aim of this study was a comparative evaluation of the content of bioactive compounds in organic and conventional coffee (Coffea arabica)originating from Brazil during 12 months storage. The content of the polyphenolic compounds was determined using HPLC analysis. The obtained results indicate that organic or conventional production and roasting conditions (light, medium, dark roast) affect the polyphenolic compounds of coffee. The highest content of total polyphenolic compounds was determined in coffees roasted in light and medium roasting conditions. Furthermore, organic coffee beans showed higher content of bioactive compounds (total phenolic, phenolic acids and flavonoids) than conventional coffee beans. During 12 months storage a decrease in polyphenolic compounds is observed and it is connected with the degradation of chlorogenic acid, which influences total bioactivity. Moreover, the highest caffeine content was observed in light and medium roasted coffee and after storage an increase in caffeine content was observed only in organic coffee beans.

25 August 2020 in Agriculture
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KKKatarzyna Król
Katarzyna Król
MGMagdalena Gantner
Magdalena Gantner
Hazelnut (Corylus avellana L.) is a popular tree nut worldwide, and in recent years, the production of hazelnuts has increased in many countries due to large investments improving agricultural techniques and the selection of new cultivars. Turkey, the leader of global hazelnut production, has shown that supply can strongly fluctuate, which leads to peak prices and market instability. In this review, an overview of the morphological traits, nutritional value, fatty acid composition, tocopherols, and future prospects of hazelnut production are described. Furthermore, information regarding hazelnuts from different geographical origins (Chile, Croatia, Iran, Italy, Oregon (US), Poland, Portugal, Serbia, Spain, and Turkey; total of 22 cultivars) to enhance the utilization of hazelnut cultivars from newly producing orchards and origins is comprehensively summarized.

20 September 2022 in Molecules
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MGMagdalena Gantner
Magdalena Gantner
KKKatarzyna Król
Katarzyna Król
APAnna Piotrowska
Anna Piotrowska
BSBarbara Sionek
Barbara Sionek
ASAnna Sadowska
Anna Sadowska
MWMateusz Wiącek
Mateusz Wiącek
Entomophagy, that is, the consumption of insects, is gaining more and more popularity. The research carried out so far on the use of edible insects in the food industry has shown that they are a valuable source of protein, and do not significantly affect the functional and sensory properties of food. Edible insects also contribute to sustainable, environment friendly food production. Taking the above into account, the influence of adding insect powder on the physicochemical properties, sensory characteristics, and microbiological qualities of wheat bread was evaluated. This study aimed to partially replace wheat flour (5, 10, and 15%) in bread with mealworm powder (T. molitor) to produce protein-fortified bread. Bread containing mealworm powder showed similar density and water activity compared to the control wheat bread. The addition of mealworm powder did not negatively affect the properties of bread. The total color difference increased significantly (p < 0.05) with the insect flour share in bread formulation and ranged between 2.27 for M5, 4.00 for M10, and 4.50 for M15. The protein content in bread fortified with 5–15% mealworm powder increased by 15–59% compared to the control bread, whereas fat content increased by 35% to 113%. Results of sensory evaluation revealed that modification of the recipe, depending on the mealworm powder addition level, significantly (p < 0.05) affected bread color, odor, flavor, and overall sensory quality. The research showed that the optimal enrichment level is using 5% mealworm flour in the bread recipe. Moreover, the obtained variants of bread were characterized by good microbiological quality after baking. In bread M10, no yeasts and molds were found during a period of 2 days of storage. The number of yeasts and molds in the other bread variants was relatively low. To conclude, the results confirmed the usefulness of insect powder in making protein-fortified bread of good quality comparable to traditional wheat bread.

6 February 2020 in Agriculture
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KKKatarzyna Król
Katarzyna Król
MGMagdalena Gantner
Magdalena Gantner
APAnna Piotrowska
Anna Piotrowska
Ewelina HallmannEwelina Hallmann
Ewelina Hallmann
Poland is one of the largest producers of hazelnuts in Europe; however, information about the contents of biologically active compounds in hazelnuts grown in Poland is limited. The aim of this study was to analyze and compare the concentrations of phenolic acids, flavonols, and tocopherols in raw and roasted hazelnut kernels and their skin, in addition to determining the effect of the cultivar and year of cultivation. The experiment was carried out in 2016–2018, and the nuts of six hazelnut cultivars were used for research purposes. Among the detected phenolic acids, p-coumaric acid was the most abundant in roasted and unroasted kernels, whereas the apigenin content represented 43%–45% of the total flavonols. The harvest year had a significant effect on the polyphenol content of hazelnuts, whereas roasting had a minor impact. The hazelnut skin contained 168- to 378- fold higher contents of total phenolic compounds than the raw and roasted nuts. Gallic acid was the most abundant phenolic acid in hazelnut skin, contributing 95.0% of the total polyphenols on average. α-Tocopherol was the most abundant tocopherol in the hazelnut cultivars, followed by β + ƴ-tocopherol and δ-tocopherol in hazelnut cultivars. The statistical analysis showed that roasting and year of cultivation did not affect the tocopherol contents of the investigated samples.

31 October 2019 in Agronomy
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KKKatarzyna Król
Katarzyna Król
MGMagdalena Gantner
Magdalena Gantner
APAnna Piotrowska
Anna Piotrowska
In the present study, the nut and kernel traits of six hazelnut cultivars (‘Barceloński’, ‘Kataloński’, ‘Webba Cenny’, ‘Olbrzym z Halle’, ‘Cosford’, and ‘Nottinghamski’) grown in Poland were investigated. Results showed that significant differences estimated among all six cultivars with all selected morphological traits and compositional properties. During statistical analysis the year of the study was not found to affect most of the investigated traits. The investigated cultivars showed a lower protein content (11.27–13.44%), higher carbohydrate content (16.40–21.79%) and similar fat content (58.91–63.83%) to nuts grown in a warmer climate like Turkey, Italy or Spain. The studied hazelnut varieties were large-sized with diameters greater than 20 mm. The nuts of the ‘Barceloński’, ‘Kataloński’ and ‘Olbrzym z Halle’ cultivars were characterized by the smallest diameters of nut and kernel, were the most spherical (0.85–0.95) and exhibited the largest average nut volume (4.26–4.46). Significant differences were found between the cultivars for oil content and the ratios of major fatty acids. The QDA results, estimated that other than shape, the evaluated nuts significantly differed only in the intensity of nutty flavor (4.88–5.92). The highest intensity of this attribute was found in three cultivars, ‘Nottinghamski’, ‘Cosford’, ‘Olbrzym z Halle’, whereas the lowest estimate was found in the ‘Barceloński’ cultivar, which was also slightly less sweet and more bitter. As a result, the present study showed that the investigated hazelnut kernels can be divided into two groups: ‘Nottinghamski’, ‘Cosford’, and ‘Webba Cenny’ are suitable for table consumption, while ‘Barceloński’, ‘Kataloński’, and ‘Olbrzym z Halle’ are suitable for the processing industry. The current experimental results may help to growers and breeders when choosing the cultivars for new plantations and possibilities of destinations of the produced nuts, for confectionery use or table consumption.

12 October 2021 in Agronomy
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KKKatarzyna Król
Katarzyna Król
MGMagdalena Gantner
Magdalena Gantner
APAnna Piotrowska
Anna Piotrowska
Poland is one of the largest producers of hazelnuts in Europe; however, information regarding the storage of cold-pressed hazelnut oil is limited. Thus, the aim of this study was to determine the oxidative indices and fatty acid composition of oils from six hazelnut cultivars during 9 months of storage. At the beginning of storage, the hazelnut oils showed zero or very low oxidation values, which indicated the absence of initial triglyceride hydrolysis and fatty acid oxidation. Acid values increased with storage time, which was statistically significant, ranging from 0.17 to 0.34 mg KOH/g oil. The peroxide value in the first 5 months of storage was undetectable, whereas after 9 months the oils showed a slight increase in oils obtained from the ‘Olbrzym z Halle’ cultivar, followed by the ‘Barcelonski’ cultivar, at 3.39 and 2.15 meq O2/kg, respectively. The lipid content of the kernels was very stable under storage conditions. Total monounsaturated fatty acid content exhibited the highest proportion, while saturated fatty acids (SFAs) had the lowest content over the entire storage period. The percentage of polyunsaturated fatty acids showed a small decrease during storage, but was not statistically significant; therefore, polyunsaturated fatty acid remained stable. The percentage of monounsaturated fatty acids decreased by approx. 1.6%, thus the percentage of SFA increased by approx. 13.7% during 9 months of storage. The oil yield ranged from 69% for nuts from the ‘Nottinghsamski’ cultivar to 75% from the ‘Webba Cenny’ and ‘Barcelonski’ cultivars.