Jaromír Pořízka

Dr. Jaromír Pořízka

orcid

Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

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

Representative Publications

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26 January 2019 in Potravinarstvo Slovak Journal of Food Sciences
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Journal Article
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PDPavel Divis
Pavel Divis
JPJaromír Pořízka
Jaromír Pořízka
Jakub KřikalaJakub Křikala
Jakub Křikala
Drinking coffee has become part of our everyday culture. Coffee cultivation is devoted to over 50 countries in the world, located between latitudes 25 degrees North and 30 degrees South. Almost all of the world's coffee production is provided by two varieties, called ‘Arabica’ and ‘Robusta’ whereas the share of Arabica is 70% of the world's coffee harvest. Green (raw) coffee can not be used to prepare coffee beverages, coffee beans must first be roasted. Roasting coffee and reaching a certain degree of coffee roasting determine its flavor and aroma characteristics. In the present study the fate of sucrose, chlorogenic acid, acetic acid, formic acid, lactic acid, caffeic acid, total phenolic compounds and 5-hydroxymethylfurfural was studied in coffee (Brazil Cerrado Dulce, 100% Arabica) roasted in two ways (Medium roast and Full city roast). It has been found that almost all sucrose has been degraded (96 – 98%) in both roasting ways. During Medium roast 65% of chlorogenic acid contained in green coffee was degraded while during Full city roast it was 85%. During both Medium and Full city roasting, the formation of acetic acid but especially formic and lactic acid was recorded. The highest concentration of organic acids was recorded at Full City roasting at medium roasting times (3.3 mg.g-1 d.w. acetic acid, 1.79 mg.g-1 d.w. formic acid, 0.65 mg.g-1d.w. lactic acid). The amount of phenolic substances also increased during roasting up to 16.7 mg.g-1 d.w. of gallic acid equivalent. Highest concentrations of 5-hydroxymethylfurfural were measured at medium roasting times at both Medium (0.357 mg.g-1 d.w.) and French city (0.597 mg.g-1 d.w.) roasting temperatures. At the end of roasting, the 5-hydroxymethylfurfural concentration in coffee were 0.237 mg.g-1 d.w. (Medium roast) and 0.095 mg.g-1 d.w. (Full city roast).

1 November 2019 in Biochemical Engineering Journal
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Journal Article
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INIvana Novackova
Ivana Novackova
DKDan Kucera
Dan Kucera
JPJaromír Pořízka
Jaromír Pořízka
IPIva Pernicova
Iva Pernicova
PSPetr Sedlacek
Petr Sedlacek
Stanislav ObrucaStanislav Obruca
Stanislav Obruca

7 July 2023 in Foods
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JPJaromír Pořízka
Jaromír Pořízka
ZSZuzana Slavíková
Zuzana Slavíková
KBKarolína Bidmonová
Karolína Bidmonová
MVMiroslava Vymětalová
Miroslava Vymětalová
PDPavel Divis
Pavel Divis
This study investigated the effect of fortifying baked goods with wheat bran (WBPI) and whey protein isolates (WPI) on their physicochemical and sensory properties. The aim was to enhance the nutritional value by incorporating high-protein ingredients. WBPI and WPI, which are rich in essential amino acids, were chosen to create high-protein flour blends. The main advantage of WBPI is that it is derived from readily available and inexpensive wheat bran. High-protein flour blends fortified with substitutions of 5%, 10%, and 15% flour with WBPI and WPI were subjected to chemical and rheological analysis. WBPI substitution slightly increased water binding and softening, but it resulted in a decrease in dough quality. In contrast, WPI substitution prolonged dough development time, improved dough stability, and enhanced farinographic quality. WBPI-substituted dough exhibited comparable extensographic properties to the reference flour, with 5% WBPI substitution leading to improved energy and dough resistance. However, as the level of WBPI flour substitution increased, extensographic parameters gradually declined without further enhancing the dough’s mechanical properties. Samples with 5% WPI substitution demonstrated superior mechanical properties compared to the reference sample. Baguette with high WBPI substitution was associated with reduced overall acceptance due to a bitter taste caused by the presence of small peptides, ferulic acid, and tannins, as confirmed by correlation analysis.

24 September 2012 in Journal of Elementology
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Journal Article
Closed access
PDPavel Divis
Pavel Divis
MVMilena Vespalcová
Milena Vespalcová
JPJaromír Pořízka
Jaromír Pořízka
AMAleš Matějíček
Aleš Matějíček
JKJiří Kaplan
Jiří Kaplan

15 November 2017 in Journal of Thermal Analysis and Calorimetry
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Journal Article
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PŠPavel Šiler
Pavel Šiler
IKIva Kolářová
Iva Kolářová
RNRadoslav Novotný
Radoslav Novotný
JMJiří Másilko
Jiří Másilko
JPJaromír Pořízka
Jaromír Pořízka
TOTomáš Opravil
Tomáš Opravil

1 September 2015 in Acta Alimentaria
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Journal Article
Closed access
JCJ. Cetkovská
J. Cetkovská
PDPavel Divis
Pavel Divis
MVM. Vespalcová
M. Vespalcová
JPJaromír Pořízka
Jaromír Pořízka
VŘV. Řezníček
V. Řezníček
The ascorbic acid, total polyphenols, total anthocyanins and mineral content, together with antioxidant activity, was determined in five Czech, two Ukrainian and two Austrian cultivars of cornelian cherry (Cornus mas L.) widely grown in the Czech Republic. Ascorbic acid content varied between 199–433 mg kg−1, total polyphenols between 2174–6143 mg kg−1, and total anthocyanins between 61–253 mg kg−1. All fruits were good sources of major metals (K, Ca, Mg, Fe, and Mn) and trace elements (Cu, Zn, and Cr). The antioxidant activity was determined by EPR and DPPH radical scavenging assay and ranged from 29.5% to 67.2%. There was a linear relationship between antioxidant activity and total polyphenol content. Based on the obtained results, Ekotišnovský, Fruchtal, and Ruzyňský cultivars were recommended for further investigation and breeding programme of cornelian cherry fruit in the Czech Republic