Olga Cwiková

Dr. Olga Cwiková

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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26 August 2020 in Foods
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Journal Article
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RLRadka Langová
Radka Langová
Miroslav JůzlMiroslav Jůzl
Miroslav Jůzl
OCOlga Cwiková
Olga Cwiková
Ivica KosIvica Kos
Ivica Kos
The influence of the drying technique on certain quality attributes of dried grapes was analysed. Five varieties of grape were used in this study (Bezsemenné, Perlette, Vrboska, Beauty seedless, and Jakubské). All the varieties were dried using four methods: drying at 40 °C, combined drying (70, 65, and 60 °C), drying at 70 °C, and lyophilisation. The quality attributes such as total soluble solids, water activity, content of vitamin C, the colour parameters (L*, a*, b*), and microbiological (colony forming units, moulds, yeasts) and sensory (smoothness, gloss, colour, odour, chewability, juiciness, flavour, and overall impression) analysis were determined, depending on the method of drying. Lyophilised grapes from the Jakubské variety had the highest vitamin C content. They contained 0.58 mg of vitamin C per 100 g of dried grapes. However, no significant differences between varieties in vitamin C content were found. This confirmed concerns about the negative impact on the nutritional quality of dried grapes with increasing temperature. The lowest total count of microorganisms (CFU), moulds, and yeasts were determined after using highest drying temperature (70 °C). Higher CFU values were determined in lyophilised grapes, and then followed by grapes dried at 40 °C. Lyophilised grapes and grapes dried at 40 °C achieved the best sensory rating in general. The final product was intended to have a unique appearance while maintaining the evaluated quality parameters.

11 June 2024 in Pharmaceuticals
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MMMichał Miłek
Michał Miłek
GFGabriela Franke
Gabriela Franke
MTMonika Tomczyk
Monika Tomczyk
MGMiłosz Górecki
Miłosz Górecki
OCOlga Cwiková
Olga Cwiková
MDMałgorzata Dżugan
Małgorzata Dżugan
Ethanol extracts obtained from 13 poplar propolis samples originating from various European countries by traditional maceration were tested for total polyphenols, flavonoid content, and antioxidant activity. Moreover, the content of 18 polyphenolic compounds (from the group of phenolic acids and flavonoids) was determined using the HPLC method. The inhibitory effect of six selected extracts with the highest activity was assessed by well-diffusion method against five strains (Bifidobacterium spp., L. rhamnosus, L. acidophilus, E. coli, and Bacteroides spp.) of intestinal bacteria self-isolated from the faeces of obese probands with the use of selective media. It was found that the antioxidant activity of propolis varied depending on geographical origin and even among samples from the same region, which indicates that some other factors also influence propolis quality. The samples of different geographical origin varied mainly in the share of individual phenolic compounds, and it was not possible to find a characteristic marker of origin, excluding the galangin present in the Polish samples only. Assessing the inhibitory activity of propolis (in the range of 70 mg to 10 µg per mL) indicated that the concentration of 100 µg/mL was found as being safe for tested fecal bacteria (Bifidobacterium spp., L. rhamnosus, L. acidophilus, E. coli, and Bacteroides spp.). As no negative effect of low doses of propolis on the intestinal microflora was found, it can be suggested that its use in recommended doses brings only beneficial effects to the body.

26 January 2019 in Potravinarstvo Slovak Journal of Food Sciences
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OCOlga Cwiková
Olga Cwiková
GFGabriela Franke
Gabriela Franke
Cheeses belong to high protein foods in which enzymatic and microbial activities form amino acids, which are then converted into biogenic amines (BAs) by the activity of bacterial decarboxylases. The most important conditions for BA formation include the presence of microorganisms, the availability of substrate, temperature and storage period, water activity, salt concentration, and the hygiene of the manufacturing process. Tyramine, histamine, 2-phenylethylamine, tryptamine, cadaverine, putrescine, spermidine and spermine were detected in smear ripened cheeses stored in different temperature regimes. The highest (p < 0.05) total BA content was found when storing the cheeses at the end of BBD (best before date) after 35 days in storage regime (A) or (C). During storage in regime (B), the total BA content (p < 0.05) after 49 days of storage was higher than on the production date (B/0). During storage, the tyramine content in regime (B) did not change (p > 0.05), while in the temperature regimes (A) and (C), the highest levels of tyramine and putrescine content were recorded in cheeses at the end of BBD after 35 days ripening. The content of polyamines in cheeses was higher (p < 0.05) at the end of storage than at the beginning, in all temperature regimes.

24 July 2025 in Foods
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TKTomáš Komprda
Tomáš Komprda
OCOlga Cwiková
Olga Cwiková
VKVojtěch Kumbár
Vojtěch Kumbár
GFGabriela Franke
Gabriela Franke
PKPetr Kouřil
Petr Kouřil
AZAlena Zouharová
Alena Zouharová
With increasing popularity of food delivery services, the microbial safety of transported meals should be ensured. An effect of the type of a meal (cooked rice; mashed potatoes; mushroom sauce), inner primary packaging (sugarcane bagasse [SB] tray; polypropylene [PP] tray), secondary container (polyester/polyethylene foam/aluminum foil [PPA] bag; PP box) on the time interval of the internal hot ready-to-eat (RTE) meal temperature decrease to the value critical for Bacillus cereus growth (40 °C) was tested during a simulated delivery; in aliquot samples of the same meals, B. cereus growth was quantified presuming a natural contamination of the meals. Type of a meal had no effect on the tested time interval (p > 0.05). Packaging a meal in the PP tray as compared to the SB tray and inserting primary trays into the PP box instead of PPA bag delayed (p < 0.05) the internal meal temperature decrease by 50 and 15 min, respectively. Average B. cereus counts in the naturally contaminated meals after the four-hour culturing at 40 °C was 2.99 log CFU·g−1. It was concluded that a hot RTE meal delivered up to four hours under the tested conditions is not likely to facilitate B. cereus growth above unacceptable levels.

8 September 2023 in Food Science & Nutrition
Verified
Journal Article
Open access
TKTereza Kacalova
Tereza Kacalova
AJAlzbeta Jarosova
Alzbeta Jarosova
OCOlga Cwiková
Olga Cwiková
GFGabriela Franke
Gabriela Franke
TSTereza Soumarova
Tereza Soumarova
Flavoring olive oil is an increasing trend in olive oil processing. Growing consumer interest in flavored olive oils by natural material brings the need to evaluate the key limiting factors which is its microbiological stability. The present research compares the microbiological quality of olive oil flavored by 3 flavors (rosemary, garlic, and lemon), prepared by 3 methods to determine changes during storage. The comprehensive microbiological analyses (total number of microorganisms [TCM], anaerobic sporulates, yeasts, molds, bacteria of the family Enterobacteriaceae, bacteria of the genus Salmonella spp., Clostridium botulinum, and lactic acid bacteria) were conducted during 12 months of storage. The best results in TCM were observed in the oil flavored by fresh garlic (0.24 log CFU/mL). The highest counts of anaerobic sporulates were detected in the dried rosemary olive oil (1.10 log CFU/mL). The flavoring materials have significantly higher counts of microorganism than flavored oils (p < .05). The obtained results demonstrated that microorganisms are capable to survive in flavored olive oil and the method of flavoring can affect their growth in a selective way according to the chemical characteristics.

19 June 2025 in Preprints.org
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TKTomáš Komprda
Tomáš Komprda
OCOlga Cwiková
Olga Cwiková
VKVojtěch Kumbár
Vojtěch Kumbár
GFGabriela Franke
Gabriela Franke
PKPetr Kouřil
Petr Kouřil
AZAlena Zouharová
Alena Zouharová
With increasing popularity of food delivery services, the microbial safety of transported meals should be ensured. An effect of the type of a meal (cooked rice; mashed potatoes; mushroom sauce), inner primary packaging (sugarcane bagasse [SB] tray; polypropylene [PP] tray), secondary container (polyester/polyethylene foam/aluminum foil [PPA] bag; PP box) on the time interval of the internal hot ready-to-eat (RTE) meal temperature decrease to the value critical for Bacillus cereus growth (40 °C) was tested during a simulated delivery; in aliquot samples of the same meals, B. cereus growth was quantified presuming a natural contamination of the meals. Type of a meal had no effect on the tested time interval (p > 0.05). Packaging a meal in the PP tray as compared to the SB tray and inserting primary trays into the PP box instead of PPA bag delayed (p < 0.05) the internal meal temperature decrease by 50 and 15 minutes, respectively. Average B. cereus counts in the naturally contaminated meals after the four-hour culturing at 40 °C was 2.99 log CFU/g. It was concluded that a hot RTE meal delivered up to four hours under the tested conditions is not likely to facilitate B. cereus growth above unacceptable levels.