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Common bean (Phaseolus vulgaris L.) seed germination improves the essential amino acid profile, flavonoid content and expansion indexShort Communication

Luis Díaz-Batalla, Karina Aguilar-Arteaga, Javier Castro-Rosas, Reyna Nallely Falfán-Cortés, Ricardo Omar Navarro-Cortez, Carlos Alberto Gómez-Aldapa

Czech J. Food Sci., 2023, 41(1):73-77 | DOI: 10.17221/5/2022-CJFS

Common bean (Phaseolus vulgaris L.) is one of the most important grain legume foods for the human diet. Common bean seed is gaining attention due to its content of secondary metabolites with positive effects on human health. The present work analysed the effect of common bean germination on the essential amino acid profile, active compound content, and expansion index after extrusion processing. The content of tryptophan (Trp) in raw common bean (RCB) and in germinated common bean (GCB) seeds was 6.1 and 7.9 mg·g–1 of protein, respectively. The limiting amino acids in RCB were sulphur amino acids and Trp, and in GCB only the sulphur amino acids were the limiting amino acids. The germination process in beans increases the levels of quercetin and kaempferol and allows the synthesis of daidzein and genistein, and significantly increases the expansion index after extrusion processing. The germination of common bean could be used as a strategy to improve nutritional, nutraceutical, and processing properties.

Improving the nutritional quality of cereals and legumes by germinationOriginal Paper

Ayºe Seda ªenlik, Derya Alkan*

Czech J. Food Sci., 2023, 41(5):348-357 | DOI: 10.17221/44/2023-CJFS

Cereal and legume grains are germinated to improve their nutritional and sensory qualities. This study investigated the effect of germination on the physicochemical properties of some grains and legumes grown in Türkiye. At the end of the germination for 48 h and 96 h at 24 ± 1 °C, carbohydrate, protein, lipid, dietary fibre, dry matter, ash, total phenolic content, antioxidant capacity and colour analyses of the germinated grains were determined. The results indicated that the germination process increased the phenolic content of all samples. The legume seeds' 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity significantly increased with germination. The germination process significantly decreased the total carbohydrate contents of the samples. A statistically significant decrease was found for the protein content of barley and corn, especially by 48 h of germination. The lipid content of cereal grains decreased as germination progressed. It might be recommended to improve the functional properties of cereals and legumes by germination and their use in the food industry.


The effects of heat treatment on the quality of fat in flaxseeds and chia seedsOriginal Paper

Matej Brestenský, Soòa Nitrayová, Peter Patrá¹

Czech J. Food Sci., 2023, 41(1):21-28 | DOI: 10.17221/159/2022-CJFS


Flaxseeds (Linum usitatissimum L.) (FS) and chia seeds (Salvia hispanica L.) (ChS) contain fatty acids (FA) with beneficial health effect for the human body. Some people often use them as part of boiled or baked dishes. Therefore, the aim of this study was to observe the effect of FS and ChS heat treatments at 40 °C and 150 °C for 20 min on the content of fat, FA, atherogenicity index (AI) and thrombogenicity index (TI), and total antioxidant activity (TAA) in comparison with heat treatments at 20 °C. The content of fat in FS was higher in comparison with ChS (P < 0.05). Similarly, the content of alpha-linolenic acid, oleic acid, polyunsaturated FA, and monounsaturated FA was greater (P < 0.05) in FS when compared with ChS. However, n6 : n3 ratio [n6 – omega 6 polyunsaturated FA (PUFA), with first double bound on 6th carbon; n3 – omega 3 PUFA, with first double bound on 3rd carbon], AI and TI were lower (P < 0.05) in FS in comparison with ChS. The TAA in FS was 37% lower (P < 0.05) compared to ChS, moreover TAA in FS decreased (P < 0.05) at 150 °C in comparison with 20 °C and 40 °C. No effect of different heat treatments was observed on the content of FA or AI and TI in FS and ChS.

Technological approaches applied in the design of gluten-free bakery productsReview

Rodica Siminiuc*, Dinu Țurcanu

Czech J. Food Sci., 2023, 41(3):155-172 | DOI: 10.17221/180/2022-CJFS


Gluten-free (GF) bakery products differ significantly from standard wheat flour products, usually with inferior characteristics. To reproduce the visco-elastic properties of wheat flour dough, GF bread is balanced by complex formulations based on gluten-free flour and starches, including hydrocolloids. They must ensure maximum similarity with conventional products to reduce the resistance of final consumers to GF products. Identifying formulations or technologies that would help mimic the gluten matrix has been and remains the focus of research in GF product design. Most research focuses on ingredients. This study provides an overview of the various technological strategies in designing GF bakery products: technologies applied to cereals, flours, dough, and final products. The study could broaden the boundaries regarding developing, selecting, and using technologies to design GF products. It would also serve as a support for further research into the development of GF products, perhaps by leveraging local products and ingredients and adapting efficient, low-cost, environmentally friendly (including combined) technologies in such a way as to obtain products with high nutritional, rheological and organoleptic value.

Quality characteristics and antioxidant activity of goat milk yoghurt fortified with Lycium ruthenicum Murr. fruitOriginal Paper

Kongyang Wu, Jiafei Huang, Panpan Bu, Hang Gao, Tongxiang Yang, Mingyan Shi, Jianming Han, Yilin Fan

Czech J. Food Sci., 2023, 41(5):382-392 | DOI: 10.17221/77/2023-CJFS


This study aimed to analyse the influence of adding Lycium ruthenicum Murr. fruit (LRF) on physicochemical, sensory characteristics and antioxidant capacity in goat milk yoghurt (GMY) during 21 days of refrigerated storage. Three different yoghurt formulations were processed using varying amounts of added LRF (1.0, 1.5, and 2.0%). LRF supplementation improved some of the physicochemical characteristics and sensory characteristics of GMY. With the increase of LRF addition, the pH of GMY showed a downward trend, and the titrated acidity showed an upward trend. The corresponding number of colonies in the storage period was higher than that of yoghurt without LRF. The addition of a concentration of 1.0–2.0% LRF played a role in the proliferation of lactic acid bacteria, and viscosity and hardness increased with increasing LRF addition. Although the susceptibility to syneresis of GMY showed a downward trend with increasing LRF addition, the scavenging rate of DPPH (2,2-diphenyl-1-picrylhydrazyl), •OH (hydroxyl free radicals), and the reducing power of Fe3+ of the corresponding concentration of GMY increased. In general, GMY with LRF addition can combine the two nutrients and have higher nutritional value, which is a good supplement to the same types of products in the market.

Nutritional composition analysis and quality evaluation of cattle in different regions of Guizhou Province (China)Original Paper

HaoXiang Xu, WenJu Luo, Lu Lei, JiuLing Long, Bo Yu, YuanFeng Zhao, Rong Ai, Jiang Lingling, Jiang Ran, JingRui Zhou (email: 296655827@qq.co

Czech J. Food Sci., 2023, 41(6):455-472 | DOI: 10.17221/133/2023-CJFS

This study aimed to investigate the variations in nutritional composition among different breeds of cattle in Guizhou. Specifically, this study selected Guanling, Weining, Sinan, Wuchuan, and Simmental cattle as experimental subjects. Assessing the nutritional quality of the longissimus dorsi muscle involves evaluating various parameters, including ultimate pH (pHu), meat colour, water-holding capacity, shear force, protein and fat content, levels of organic acids and amino acid composition. The study's findings indicated notable variations among the muscles of different cattle breeds tested. Guanling, Wuchuan, and Simmental cattle exhibited the highest water-holding capacity, while Wuchuan cattle displayed the highest shear forces. Guanling cattle and Simmental cattle had the highest levels of protein and fat. Weining cattle and Simmental cattle demonstrated the highest concentrations of lactic acid and oxalic acid. Guanling cattle exhibited the highest total amino acid and essential amino acid content. Moreover, Guanling cattle and Weining cattle showed the highest lightness (L*) and yellowness (b*) values, indicating lighter meat colour, while Weining cattle had the highest redness (a*) value, indicating redder meat colour. No significant differences among the five cattle breeds were observed in pHu and propionic acid content. These results provide a theoretical basis and serve as a data reference for assessing the suitability of different beef varieties for various processing purposes.

Effect of ultrasound on isolation and properties of oat starchOriginal Paper

Esra Baºarıcı Ünlü, Çiğdem Aykaç*

Czech J. Food Sci., 2023, 41(2):111-117 | DOI: 10.17221/94/2022-CJFS

The aim of the present study was to analyse the effect of ultrasound (US) on the isolation and properties of oat starch. Starch isolation was done by a water extraction method and with sonication for 30 (US30), 45 (US45) and 60 (US60) min. The highest starch yield was found in US45 as 49.04 g·100 g–1 of oat flour when the extraction time decreased from 6 h to 45 min. The functional properties of starches, such as bulk density, water solubility index, dispersibility and water absorption capacity, ranged from 0.65 to 0.80 g·mL–1, 3.22 to 5.75%, 78 to 87.5% and 84.23 to 95.87%, respectively. US45 had lower bulk density and higher dispersibility than other starches. US treatments decreased the gelatinisation temperature ranges and increased the gelatinisation enthalpy values. The enthalpy of the gelatinisation value of oat starch was found as 8.45 J·g–1 and increased with sonication up to 13.65 J·g–1. Retrogradation endotherms were observed after 6 days of storage, and enthalpies of retrogradation were lower than in the gelatinised starches. Fourier transform infrared spectroscopy (FTIR) spectra showed that US treatment did not affect the functional groups of oat starch. US application during oat starch isolation gave desired results, such as time reduction, higher yields and increased functional properties.

Tetragenococcus halophilus, Staphylococcus xylosus and Staphylococcus saprophyticus for sardine fermentationOriginal Paper

Zhijia Fang, Wenjuan Zhu, Ying Liu, Xinran Wang, Yaling Wang, Yanyan Wu

Czech J. Food Sci., 2023, 41(4):271-278 | DOI: 10.17221/246/2021-CJFS


To improve the quality and enrich the flavour of fermented sardine, Tetragenococcus halophilus, Staphylococcus xylosus, and Staphylococcus saprophyticus were used as a mixed starter for sardine fermentation. And their proportions were optimised using response surface methodology (RSM). The highest sensory score was obtained when the proportions of T. halophilus, S. xylosus, and S. saprophyticus were 1:1:1. The optimised fermented sardine had the lowest levels of histamine content (0.0190 μg·g–1), total volatile basic nitrogen (TVBN, 208 μg·g–1), and was richer in volatile compounds (308). The results may provide important evidence that T. halophilus, S. xylosus, and S. saprophyticus may be satisfactorily used as a mixed starter to improve the quality and flavour of fermented sardines.

Comparison of physicochemical properties, phenolic profiles and antioxidant capacity of hawthorn berries stored at different temperatures and timeOriginal Paper

Xueyan Wei, Yanjing Yin, Kang Xu, Tao Wang, Chuanhe Zhu, Wen Liu, Mengmeng Guo

Czech J. Food Sci., 2023, 41(6):419-427 | DOI: 10.17221/112/2023-CJFS

This research investigated the effect of different storage temperatures on the compositional changes, physicochemical characteristics, and functional properties of hawthorn berries. Storage at 25 °C resulted in the gradual decrease of the moisture, hardness, sugar, titratable acid, and colour of hawthorn berries. These changes decreased with decreasing storage temperature, and the minimal changes happened at frozen storage (–18 °C). Similarly, the decreasing rate of ascorbic acid, extractable polyphenol (EPP), and flavonoids during storage also decreased with reducing storage temperature (25 °C > 4 °C > –18 °C). Hydrolysable polyphenol (HPP) was relatively stable during the hawthorn storage, and non-extractable proanthocyanidins (NEPA) increased with decreasing temperature. Ferric reducing antioxidant power (FRAP) of EPP and HPP decreased at 25 °C, while polyphenolic oxidase (PPO) and peroxidase (POD) activities decreased. Decreasing the storage temperature can improve the stability of the nutritional properties, antioxidant capacity, and enzyme activity of hawthorn. The specific storage temperature depends on the final processing conditions and the purposes of the hawthorn berries.

Optimising consumer acceptability of Cauca specialty coffee through roasting profiles on acidity and body sensory attributesOriginal Paper

Diego Andrés Campo-Ceballos, Carlos Alberto Gaviria-López

Czech J. Food Sci., 2023, 41(1):64-72 | DOI: 10.17221/181/2022-CJFS

The roasting coffee process is the compilation of time-temperature-dependent physical and chemical transformations induced by heat. Through the study of the time-temperature curve, the correct definition of the degree of roasting of coffee is an area of active and non-trivial research, which intervenes in obtaining consistent roasting profiles reflected in the acceptability of the drink perceived by consumers. This paper used the methodology of response surfaces (RSM) with the central composite design (CCD). A consumer study was conducted with 104 individuals, each tasting 13 cups of specialty coffee from Cauca-Colombia. Predictive equations for acidity and body perception were obtained. The roasting profile points in charge, turning point, yellow, brown, first crack, and drop step were included. Mathematical models predict the acidity and body perceptions by integrating the roasting profile points characteristics of coffee. The Cauca coffee beans produced using the optimied conditions contribute to obtaining a roasting time/temperature of 468 s at 192 °C, respectively, with acidity (9/15) and body (5.5/15) in the (0–15) intensity consumer's perception scale.

Investigation of multimycotoxins by LC-MS/MS in maise semolina chipsOriginal Paper

Oktay Samadzade, Karlo Muratoğlu, Serkan Kemal Büyükünal

Czech J. Food Sci., 2023, 41(3):212-220 | DOI: 10.17221/241/2022-CJFS


Chips made from maize semolina are rarely mycotoxin analysed because they are classified as low-risk foods in routine legal control plans. It is essential to foresee the health risks these snack foods may pose in the medium and long term, whose consumption frequency and quantity have increased with the changing consumer behaviours during the pandemic. The most outstanding development in mycotoxin analysis in recent years has been the use of high-pressure liquid chromatography together with mass spectrometry (LC-MS/MS) as a detector. For aflatoxin (AF) B1, B2, G1, G2, ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON), fumonisin B1 (FB1), fumonisin B2 (FB2), citrinin (CIT), HT-2 toxin, and T-2 toxin determination in our samples, the LC-MS/MS analysis method with electrospray ionisation interfaces was utilised. Aflatoxin B1 levels in 22.7% of the samples (2.01–17.49 μg·kg–1) and total aflatoxins (TAF) in 26.7% of the samples (6.71–24.67 μg·kg–1) were determined to exceed the limits defined in the Turkish Food Codex Contaminants Regulation. CIT could not be detected in any of the samples. ZEN + DON + OTA was found in 21.3% of the samples, DON + TAF + total fumonisins (FUM) in 19.3%, and TAF + ZEN + FUM in 18.7%.

Refined approach to the evaluation of heat resistance applied to Enterobacteriaceae in cheese stretchingOriginal Paper

Irena Nìmeèková*, ©árka Tre¹lová, Eli¹ka Le¹ková

Czech J. Food Sci., 2023, 41(5):358-366 | DOI: 10.17221/83/2023-CJFS


Heat resistance of bacteria is a factor potentially limiting the production of safety foods. We focused on five Enterobacteriaceae strains related to cheese stretching and sub-pasteurisation experimental temperatures of 50–59 °C. Heat resistance was screened and obtained data were fitted to a classical log-linear model with D-values indicating highly heat-resistant strains used. For example in Klebsiella oxytoca S525, D(50)-value was 96.1 min and D(59)-value 5.1 min. In subsequent detailed measurements, the shape of inactivation curves was sigmoid with defined lag, log-linear and stationary phase. We suggest calculating refined D-values (Dr-values) using only data obtained in log-linear phases, namely Dr(temperature; lag phase). In K. oxytoca S525, the obtained results were: Dr(50; 80.9) = 61.7 min, Dr(53; 12.4) = 36.8 min, Dr(56; < 10) = 10.6 min, and Dr(59; < 3) = 4.3 min. The research of particular inactivation phases can provide interesting findings both in science and industrial practice, especially concerning the passage or persistence of hazardous strains in food processing plants.

Screening and quantification of pesticide residues in ciders by liquid chromatography-high resolution mass spectrometryOriginal Paper

Veronika Zu¹»áková, Martin Du¹ek, Vladimíra Jandovská, Jana Ol¹ovská

Czech J. Food Sci., 2023, 41(1):29-35 | DOI: 10.17221/158/2022-CJFS

The present study aimed to apply a multi-residue method for the screening and quantification of pesticide residues in ciders, low alcoholic beverages made by fermentation of apple juice. Twenty bottled craft cider samples purchased from the Czech market were analysed for pesticide residues. The residues of pesticides were extracted from samples using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure in combination with additional solid-phase extraction (SPE) sample clean-up to achieve the lowest detection limit possible. In this study, targeted screening of pesticide residues in the samples was performed with the Q-Orbitrap mass spectrometry instrument. We identified 18 pesticides in cider samples analysed by screening method using an accurate-mass database of about 500 pesticide compounds, including their retention times, empirical formulas, and characteristic fragments. Additionally, liquid chromatography with high-resolution tandem mass spectrometer (LC-HRMS/MS) was used for re-analysis of positive findings of pesticides in samples and allowed to quantify compounds of interest at 0.2 µg L–1 concentration level. The monitoring scheme was applied to the set of craft ciders, and the results revealed the presence of pesticide residues in most of the samples at trace levels ranging from 0.5 to 5 µg L–1 and rarely at a level higher than 10 µg L–1.

The use of modern fermentation techniques in the production of traditional wheat breadOriginal Paper

Pavel Skøivan, Marcela Sluková, Ivan ©vec, Helena Èí¾ková, Iveta Horsáková, Eli¹ka Rezková

Czech J. Food Sci., 2023, 41(3):173-181 | DOI: 10.17221/39/2023-CJFS

A traditional Czech bakery white bread product is commonly made with directly mixed dough with the addition of yeast. In order to be able to reduce the salt content of the final product without compromising its acceptability to consumers, the dough was prepared with the addition of pre-ferments and wheat sourdoughs. The aim was to deepen the flavour background of the product and thus have a positive effect on its sensory properties. Wheat sourdoughs were prepared and tested using starter cultures and matured under different conditions. The resulting products were tested both sensorially and by means of precise physical methods.

Endocrine disruptors in foods: Overlooked factors contributing to the prevalence of obesityReview

Wenli Wu, Yang Yang, Bee KangTan, Shaoling Lin, Yaping Chen, Jiamiao Hu

Czech J. Food Sci., 2023, 41(6):393-405 | DOI: 10.17221/80/2023-CJFS


Endocrine disruptors, also known as endocrine-disrupting chemicals, could mimic or interfere with the body's hormones. Indeed, naturally occurring endocrine disruptors have been widely identified in daily foods. Moreover, industrialisation has resulted in increasing synthetic endocrine disruptors being produced and used as food additives or in food package materials, which makes exposure to endocrine disruptors become more common. Although the safety of synthetic chemicals has been extensively evaluated before entering into the food industry, increasing evidence has also highlighted that long-lasting exposure might influence long-term metabolic outcomes and be associated with the prevalence of obesity. Therefore, this review summarised the sources, detection methods, obesogenic effects and possible mechanisms of endocrine disruptors commonly found in foods, as well as discussed possible underlying mechanisms by which endocrine disruptors contribute to the increased risk of obesity. In conclusion, the review may provide useful information for understanding the association between endocrine disruptors and obesity, which could provide a new angle of view for preventing obesity prevalence.

Improving the extraction efficiency and functional properties of wheat germ protein by ultrasound-assistedOriginal Paper

Chunyan Xie, Juan Du, Chunmiao Xing, Xu Zhang, Lan Wang, Hongzhang Chen, Tong Lin

Czech J. Food Sci., 2023, 41(2):118-126 | DOI: 10.17221/54/2022-CJFS

his study optimised the conditions for ultrasound-assisted extraction (UAE) of defatted wheat germ protein (WGP) and evaluated its effect on the functional properties. Single-factor and orthogonal experiment designs were combined to optimise the UAE extraction condition. The extraction of WGP reached the highest level, at 88.66%, with a solid : liquid ratio of 1 : 25 g·mL–1, pH value of 9.0, ultrasonic time of 10 min, and ultrasonic power at 400 W. Under these conditions, albumin, globulin, prolamin, and glutenin accounted for 32.26, 28.52, 5.42, and 22.40% of total protein, respectively. In addition, this study compared the functional properties of WGP extracted by UAE with the results based on a commercially available soy protein (SP) isolate (SPI). The UAE of WGP had better oil absorption, foaming, and emulsifying properties. Therefore, UAE is a promising technique for food protein extraction because it can change the protein efficiencies and properties of the extract.

Chemical composition of dietary alfalfa and its effectiveness on broiler chicken thigh meat qualityOriginal Paper

Petru Alexandru Vlaicu, Arabela Elena Untea, Raluca Paula Turcu, Mihaela Saracila, Iulia Varzaru, Alexandra Gabriela Oancea

Czech J. Food Sci., 2023, 41(4):279-286 | DOI: 10.17221/79/2023-CJFS



This study aimed to evaluate alfalfa meal's chemical and nutritional composition and effectiveness on broiler chicken thigh meat quality. Alfalfa contains significant content of crude protein and fibre, minerals (iron and zinc), polyunsaturated fatty acids (PUFA), and antioxidant compounds, especially total antioxidant capacity (TAC) and total polyphenols content (TPC). To test its effectiveness on chicken tight meat quality, we developed a trial on 60 Cobb 500 broilers, divided into two groups of 30 animals each and fed during growing-finishing phases (11–42 days) a control diet (C) and an experimental diet (A), in which 5% alfalfa meal was added. At the end of the trial, six animals from each group were selected for slaughter and sampling. The analyses on meat samples revealed that alfalfa significantly affected bioactive compounds with antioxidant potential, such as zinc, vitamin E and TPC, compared with the C samples. The utilisation of 5% alfalfa was also very effective on the fatty acids composition of thigh meat samples in the A group by increasing the concentration of eicosapentaenoic acid and significantly decreasing the n-6/n-3 ratio as well as cholesterol content with 10.41% in experimental samples. Therefore, alfalfa can be a potential alternative to synthetic feed additives in producing healthier chicken meat, with increased content of bioactive compounds and essential fatty acids for human health.

Utilisation of chicken eggshell nanopowder on physicochemical quality, microstructure, and amino acid profile of beef pattiesOriginal Paper

Herly Evanuarini, Agus Susilo, Uun Yanuhar, Adelya Desi Kurniawati

Czech J. Food Sci., 2023, 41(6):428-435 | DOI: 10.17221/156/2023-CJFS

Chicken eggshells are a source of calcium and protein that can be added to restructured meat products, including patties. This study aimed to improve the chemical quality of beef patties with the addition of chicken eggshell nanopowder, including pH, protein content, ash content, fat content, antioxidant activity, calcium, microstructural quality, and identification of amino acid profiles. The method used in this study was a laboratory experiment arranged in a completely randomised design with five treatments: without the addition of chicken eggshell nanopowder as a control, the addition of chicken eggshell nanopowder 0.1, 0.3, 0.5, and 0.7% (w/w) with five replications. Data were analysed using the analysis of variance. It was followed by Duncan's multi-range test when the differences were significant or very significant. The research results show that the addition of chicken eggshell nanopowder to beef patties had a very significant effect (P < 0.01%) on pH, protein content, ash content, fat content, antioxidant activity, calcium, microstructural quality through scanning electron microscopy, and several amino acids. The addition of 0.7% chicken eggshell nanopowder could improve the chemical quality of the beef patties. The patty matrix was uniform and compact, and the air voids were getting tighter with the addition of chicken eggshell nanopowder, which was increasing based on scanning electron microscopy observations. Moreover, beef patties had various types of amino acids to achieve the best treatment.


Fermentation of pineapple juice with Lactiplantibacillus plantarum subsp. plantarum Dad-13: Sensory and microbiological characteristicsOriginal Paper

Fariz Nurmita Aziz, Tyas Utami, Dian Anggraini Suroto, Rini Yanti, Endang Sutriswati Rahayu

Czech J. Food Sci., 2023, 41(3):221-229 | DOI: 10.17221/243/2022-CJFS


Among the varieties of pineapples, honey pineapple is suitable to be processed as a probiotic beverage. The study aimed to evaluate the honey pineapple juice as a growth medium for Lactiplantibacillus plantarum subsp. plantarum Dad-13 probiotic strain. The pineapple juice was fermented by adding a starter culture of L. plantarum Dad-13. The fermentation time (0, 4, 8, 12, 16, 20, and 24 h) was used as a variable. The number of L. plantarum Dad-13 cells increased significantly after fermentation (P < 0.05). In acidic pineapple juice L. plantarum Dad-13 can still grow more than 2 log cycles. After 16 h, the results showed the best characteristics with cell count (8.86 log CFU·mL–1), pH (3.52), and titratable acidity (0.59%). To balance the sour taste, the 8% sucrose addition was the most preferred by the panellists (n = 67), with a 5.74 (slightly like) overall acceptance score. After 42 days, there was no significant decrease in cell viability. The number of cells on day 42 was 8.81 log CFU·mL–1 with significant changes in pH and titratable acidity. The study showed that honey pineapple juice is a suitable growth medium for Lplantarum Dad-13.

Physical, mechanical, and antioxidant properties of alginate/pectin edible films with incorporated chokeberry and wild thyme extractsOriginal Paper

Svetla Maksimova Dyankova*, Ayten Osman Solak

Czech J. Food Sci., 2023, 41(5):367-374 | DOI: 10.17221/94/2023-CJFS


The purpose of the present study was to develop edible composite films based on sodium alginate and pectin with incorporated Aronia melanocarpa (Michx.) Elliot and Thymus serpyllum L. extracts. The influence of the extracts on the physicochemical, optical, mechanical, and antioxidant properties of the films was investigated. The addition of the extracts changed the colour parameters and significantly increased the barrier properties to UV and visible light. This effect is more pronounced in the film with chokeberry extract and is due to the anthocyanins contained in it (75.43 μg cyd eq·g–1, cyd eq – cyanidin equivalents). The antioxidant activity of films with incorporated extracts was 4-fold (thyme) to 7-fold (chokeberry) higher than the control alginate/pectin film. A significant improvement in the mechanical characteristics of the films with extracts was found. The values for tensile strength were 9.41 MPa (chokeberry) and 9.54 MPa (thyme), while for the film without extract – 4.63 MPa. The resulting films could find potential application as active packaging with antioxidant properties, which could increase the quality and extend the shelf life of the foods packaged in them.

Challenging the problematic detection of clostridial isolates causing late-blowing defect with MALDI–TOF MSOriginal Paper

Pelin Ertürkmen, Zübeyde Öner

Czech J. Food Sci., 2023, 41(1):36-43 | DOI: 10.17221/199/2022-CJFS

The present study aimed to evaluate the Clostridium spp. counts in corn silage, raw milk and Kaºar cheese and to identify the clostridial isolates causing a late-blowing defect (LBD) potential using matrix-assisted laser desorption-ionization-time of flight mass spectrometry (MALDI-TOF MS). Lactate-fermenting clostridial spores (LFCS) were determined by the most probable number method (MPN) in 14 samples of corn silage, 12 samples of raw milk and 20 samples of Kaºar cheese. 181 isolates were obtained from MPN gas-positive tubes. Gram staining, catalase and oxidase activity, anaerobic development tests and Scanning Electron Microscopy (SEM) imaging showed that 95 isolates were typical clostridial bacteria. Sixty-six isolates could maintain viability during the passage and stock stages. A confirmatory identification technique was then performed using MALDI-TOF MS. The results revealed that (49 out of 66 isolates) of bacteria were correctly identified as 38 (77.55%) Clostridium sporogenes, 6 (12.24%) Clostridium butyricum, 3 (6.12%) Clostridium beijerinckii, 1 (2.04%) Clostridium bifermentans and 1 (2.04%) Clostridium sartagoforme. This study determined that clostridial isolates that cause LBD can be identified successfully and quickly by MALDI-TOF MS, a novel method for detecting anaerobic bacteria.

Effect of onion waste powder on the rheological characteristics, sensory attributes, and antioxidant properties of mayonnaiseOriginal Paper

Tsvetko Prokopov, Kremena Nikovska, Milena Nikolova, Pavel Merdzhanov, Mina Dzhivoderova-Zarcheva

Czech J. Food Sci., 2023, 41(3):182-188 | DOI: 10.17221/19/2023-CJFS


The recovery and utilization of onion processing waste would contribute to the solution of environmental problems. This research presents the way of successful supplementation of onion processing waste in mayonnaise. Different levels (0, 1, 2, and 3%) of onion waste powder (OWP) were used as an additive to mayonnaise, based on sunflower oil. The final mayonnaise formulations were evaluated for sensory properties, rheological behaviour, oxidative stability, total phenolic content, total flavonoids, and antioxidant activity. The results indicated that OWP could be used as a potential health-promoting functional ingredient in amounts of 2% to produce mayonnaise enriched with total phenolic compounds and flavonoids, having high antioxidant activity, acceptable quality, and overall consumer preference.

Ultra-high-pressure technology for preservation of fresh aquatic foods: A reviewReview

Jiakun Peng, Chune Liu, Kaikai Bai, Shaohua Xing, Feng Liu

Czech J. Food Sci., 2023, 41(5):313-322 | DOI: 10.17221/87/2023-CJFS


Aquatic foods such as fish, shrimp, and shellfish are important human nutrient sources. However, aquatic foods spoil quickly during processing and storage due to spoilage bacteria and endogenous enzymes. Ultra-high-pressure (UHP) technology, as an advanced non-thermal treatment method, is an effective preservation technique for aquatic foods. The mechanism of UHP technology is to destroy non-covalent bonds by UHP, which leads to the change of cell membrane permeability and the destruction of high-level structure of proteins, making apoptosis and enzyme inactivation. The technology can effectively sterilise and preserve food's colour, taste and nutritional value. The paper provides an introduction to the working principles, types, sources and equipment and describes the progress of the research and application of UHP technology in pascalisation, enzyme inactivation, parasite inactivation and quality modification of aquatic products. Potential limitations and prospects of the technology are also outlined. We hope to lay the theoretical groundwork for using this technique in aquatic product processing and provide guidance for its application in industrial production.

Listeria monocytogenes clones circulating in the natural environment of the Czech Republic and SlovakiaOriginal Paper

Zuzana Tomá¹tíková, Lucie Hlucháòová, Tereza Gelbíèová, Renáta Karpí¹ková

Czech J. Food Sci., 2023, 41(2):127-136 | DOI: 10.17221/234/2022-CJFS

Listeria monocytogenes is not only a pathogen causing a serious food-borne disease in humans but can also occur as a saprophyte in the natural environment. This study aimed to evaluate the occurrence of L. monocytogenes obtained from the natural environment of the Czech Republic (hereinafter Czechia) and Slovakia in 2016–2018 and to compare the clonal relationship of strains circulating in the environment with the strains originating from the food chain and humans. Altogether, 217 samples of mud, surface water, vegetation and soil were collected in 61 locations. Samples were processed according to the modified EN ISO 11290-1 standard. The obtained L. monocytogenes isolates were characterised using serotyping, macrorestriction analysis, followed by pulsed-field gel electrophoresis, whole genome sequencing (WGS), and antimicrobial susceptibility testing. L. monocytogenes were detected in 8.8% of the examined samples and were isolated in 15 locations, mainly from the mud from the banks of the surface water sources. Altogether, 25 L. monocytogenes strains were obtained from 19 positive samples. Serotypes 1/2a, 4b, and 1/2b were detected among the strains. Twenty combined AscI/ApaI pulsotypes were obtained by macrorestriction analysis. Altogether, 12 sequence types (STs) were detected using Multi-locus sequence typing (MLST) by WGS, with ST451 being the most frequent. The core genome MLST analysis revealed a heterogeneous population of environmental strains. No phenotype resistance was detected by antimicrobial susceptibility testing. Screening of antimicrobial-resistance genes using the platform ResFinder revealed the genes fosX in 24 isolates and blaTEM-116 in one isolate. The occurrence of L. monocytogenes in various samples from natural environments within wide altitude range during different seasons of the year may highlight this bacterium's remarkable adaptability and exceptional tolerance to external factors. Serotype distribution of the strains circulating in the natural environment of Czechia and Slovakia seems to reflect distribution in the human population more than in the food chain.

Development of a novel invA gene-based real-time PCR assay for the detection of Salmonella in foodOriginal Paper

Marko Dmitric, Dejan Vidanovic, Kazimir Matovic, Bojana Tesovic, Milanko Sekler, Ivan Vicic, Nedjeljko Karabasil

Czech J. Food Sci., 2023, 41(4):287-294 | DOI: 10.17221/114/2022-CJFS


In this study, the primers and the probe were designed, and a completely new real-time polymerase chain reaction (PCR) protocol for detecting the invA gene of Salmonella in food was optimised and validated in-house. The inclusivity test used 76 different Salmonella isolates with no false-negative results. The exclusivity was tested using 45 non-Salmonella microorganisms with no false-positive results. The method was also successfully applied while examining five different artificially contaminated food categories. The results were compared to the standard method (ISO 6579-1) and two previously validated real-time PCR methods. The developed assay is sensitive and specific for rapidly detecting Salmonella in food.

Nutritional habits comparison of the baby boomer, X, Y, and Z generations located at a private college in Muğla, TürkiyeOriginal Paper

Halime Zülal Zeren, Elif Burcu Bali, Hülya Demir

Czech J. Food Sci., 2023, 41(6):436-445 | DOI: 10.17221/105/2023-CJFS

The present study aimed to reveal intergenerational differences in the nutritional habits of the baby boomer, X, Y, and Z generations at a private college in Muğla, Türkiye. The study population included the students of the TED Bodrum College in Muğla province in the 2021–2022 academic year, including 311 participants: baby boomers (74), X (66), Y (43), and Z (128) generations. An online questionnaire was used to compare the eating habits among the generations. The data were evaluated using SPSS software. Most of the generations believed in healthy eating. Physical image and social media mainly influence the healthy eating habits of the Z generation. The baby boomers and X generations mostly skipped lunch, while the Y and Z generations skipped breakfast. Baby boomers, X, and Y generations mostly prefer healthy foods; however, the Z generation attaches importance to tasty foods. Z generation's interest in nutrition mostly concerns their physical appearance, not their health. Nutritional knowledge must be strengthened, particularly among young generations, and nutrition education programs need to be better supported by the government and educational sectors.

Coumarin derivatives as antifungal agents – A reviewReview

Mirjana Lonèar, Dajana Ga¹o-Sokaè, Maja Molnar*

Czech J. Food Sci., 2023, 41(2):79-91 | DOI: 10.17221/178/2021-CJFS

Coumarins and pyridines are a promising class of naturally occurring bioactive heterocycles with unique physical and chemical properties. Compounds containing the coumarin framework possess a wide range of pharmacological, biological, and physiological activities, which makes them important for application in medicine, the food industry and agriculture. Among all coumarins' properties, it was found that coumarins may prevent fungal growth, depending on substituents linked to the coumarin core. Therefore, many coumarin derivatives have been investigated as potentially powerful agents in preventing and controlling fungal pathogens. This review summarises the latest research on coumarins and their antifungal activity to provide useful information for further developing more efficient coumarin-based fungicides.


Effect of gamma irradiation, high sugar content and antimicrobials on survival of Escherichia coli: A reviewReview

Viktória Dobó, Renáta Homlok, Csilla Mohácsi-Farkas, Ágnes Belák

Czech J. Food Sci., 2023, 41(4):231-247 | DOI: 10.17221/235/2022-CJFS


Dried fruits are popular ready-to-eat snacks. However, due to cross-contamination or contact with infected persons, Escherichia coli could be present, of which some strains are pathogenic, thus, the consumption of contaminated dried fruits could pose a public health risk. Microbial cells subjected to stress factors such as osmotic shock, radiation and antimicrobials could induce complex stress response systems and adaptation. Radiation and antimicrobials have been shown to cause an SOS response in E. coli, which affects cellular metabolism, such as the enhanced ability to repair DNA and mutagenesis. Studies have shown that glucose plays a critical role in the down- or upregulation of locus for enterocyte effacement (LEE)-encoded virulence of E. coli. Gamma radiation could also cause the formation of viable but nonculturable (VBNC) cells. If these cells are present in a sample, the number of viable cells will be underestimated by the plate count method leading to the false conclusion that the product is germ-free. We have reviewed in this article how stressors such as high sugar content, gamma radiation, and antimicrobials affect the survival of E. coli in dried fruits.

The effect of different cooking methods on the antioxidant activity of wild Swiss chard (Beta vulgaris L. var. cicla)Original Paper

Yagmur Demirel Ozbek*, Ozlem Saral

Czech J. Food Sci., 2023, 41(5):375-381 | DOI: 10.17221/114/2023-CJFS


This study aimed to investigate the effects of different cooking methods (boiling for 5 min and 8 min, microwave cooking for 3.5 min and 6.5 min, and stir-fry for 5 min and 10 min) on wild chard's antioxidant activity and total phenolic content. It was determined that the total phenolic content [1 552.00 ± 299.82 mg GAE·(100 g)–1, GAE – gallic acid equivalents] increased in 3.5 min in the microwave [2 611.33 ± 311.76 mg GAE·(100 g)–1] and 5 min in stir-frying [2 434.33 ± 197.75 mg GAE·(100 g)–1] compared to the raw chard samples (P < 0.05). Two different antioxidant activity determination methods [2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP)] were used in the study. In both methods, it was determined that antioxidant activity decreased in the 10-min application of stir-frying. In contrast, the antioxidant activity increased by applying 3.5 min and 6.5 min in the microwave (P < 0.05). As a result, it was found that the antioxidant activity and total phenol content of wild chard changed when the cooking method and time were changed.

Biodiversity of Vitis vinifera endophytes in conventional and biodynamic vineyardOriginal Paper

Maria Vrublevskaya, Thi Tra My Nguyenová, Lucie Drábová, Petra Lovecká, Blanka Vrchotová, Olga Ma»átková, Markéta Kuli¹ová, Irena Jaro¹ová Kolouchová

Czech J. Food Sci., 2023, 41(1):44-53 | DOI: 10.17221/200/2022-CJFS


Plants are permanently exposed to biotic and abiotic stress and have therefore developed intricate resistance mechanisms, consequently. These include the presence of microbial endophytes, which can promote plant growth and ensure better resilience against unfavourable conditions. These microorganisms colonising plant tissues can directly affect plant growth by producing phytohormones, antioxidants, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, or indirectly by the production of siderophores and antifungal agents. To the best of our knowledge, this is the first study devoted to assessing bacterial endophyte diversity and their plant growth-promoting properties in two utterly distinct vineyards in view of agricultural management (conventional, biodynamic) in the Czech Republic. With these different agricultural approaches, we hypothesised different numerical representations of bacterial endophytes acquired from vine shoots and leaves, which was not proved (P = 0.743, F = 0.129). A total of 470 distinct bacterial endophytes were isolated from the Vitis vinifera plants from the conventional and biodynamic vineyard and from which over 80% were identified by the matrix-assisted laser desorption-time-of-flight mass spectrometry (MALDI-TOF MS). In both vineyards, the dominant bacterial genus was Bacillus, followed by Pantoea, Pseudomonas and Staphylococcus. Plant-promoting endophyte properties varied with respect to the season and type of vineyard. The ability to produce indole-3-acetic acid (IAA) and ACC deaminase was higher in the biodynamic vineyard, in comparison with antioxidant activity, which was found in a higher proportion in isolates from the conventional vineyard.

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