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Honey: Determination of volatile compounds, antioxidant and antibacterial activitiesOriginal PaperSemiramis Karlidag, Merve Keskin, Sinan Bayram, Nazli Mayda, Asli OzkokCzech J. Food Sci., 2021, 39(3):208-216 | DOI: 10.17221/63/2021-CJFS Honey is an important functional food for human health and nutrition that is collected by honey bees and stored in the honeycombs. In this study, total phenolic content, antioxidant activity and volatile compounds of 13 different honey samples collected from various districts of Malatya province were investigated. As a result of this study, it was determined that the total phenolic content varied between 8.50 mg GAE 100 g-1 and 73.90 mg GAE 100 g-1 and it was observed that the honey samples were rich in aldehydes, aliphatic acid and esters, alcohols, hydrocarbons, carboxylic acid esters, ketones, terpenes, fatty acids and esters. In addition, the antibacterial effects of honey samples were determined against 18 different pathogenic bacteria using agar well diffusion (AWD) method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). In AWD assay, it was recorded that inhibition zone diameters varied between 9 mm and 14 mm and honey samples were found to have a partial inhibitory effect against selected target pathogens. |
Influence of the Addition of Buckwheat Flour on Gluten Free Bread Quality and Antioxidant CapacityM. Wronkowska, D. Szawara-Nowak, D. Zielińska, A. Troszyńska, M. Soral-ŚmietanaCzech J. Food Sci., 2009, 27(10):S284 | DOI: 10.17221/607-CJFS The diet based on gluten free products is characterised by a low content of some nutritional components such as proteins and mineral components, as well as non-nutritional but physiologically important components like dietary fibre. Buckwheat grains are a rich source of proteins, which have a high biological value due to the well-balanced amino-acids composition, although its digestibility is relatively low. The aim of the present research was to investigate the influence of buckwheat flour addition on gluten free bread quality and their antioxidant capacity. In this study, own gluten free bread formula, composed of corn starch, potato starch, salt, yeast, pectin, sugar and sunflower oil was investigated. The buckwheat flour substituted corn starch at final amount of 10, 20, 30, 40% w/w of total ingredients in gluten free bread formula. The breads were baked in electric oven at 200°C for 25 min. The bread samples were freeze-dried, ground and sieved. The sensory quality of buckwheat enhanced gluten free breads was analysed using sensory profiling (QDA) and hedonic tests. The measurement of macroelements content in the crumb was carried out using the atomic absorption spectroscopy (AAS) method (SORAL-SMIETANA et al. 2001). The antioxidant capacity (AC) of the breads was evaluated by cyclic voltammetry (CV) method and free radical scavenging activities of 67% methanol extracts against 2,2-diphenyl-1-picryhydrazyl radical (DPPH.) as DPPH Radical Scavenging Activity (DPPH RSA). All breads were analysed for their total phenolics content. The buckwheat enhancing gluten free breads were in accordance to the requirements of Polish Standards (PN-A-74123) for gluten-free bread. The sensory profiles of gluten-free breads were dependant on the amount of buckwheat flour added. The overall quality of breads was the highest for bread with 40% buckwheat flour addition. The positive correlation between macroelements content and increasing amount of buckwheat flour was observed in breads. The antioxidant capacity of buckwheat enhanced gluten free breads determined by CV and DPPH RSA was related to the amount of added buckwheat flour. The total phenolics content was positively correlated with antioxidant capacity of the breads. In summary, buckwheat flour as a natural source of minerals and antioxidant activity, and also as a structure-forming factor improving the sensory quality, can be used for preparation of new buckwheat enhanced gluten free breads. |
Phenolic content and antioxidant capacity of Cypriot winesFood Analysis, Food Quality and NutritionCharis M. GALANAKIS, Anestis KOTANIDIS, Maria DIANELLOU, Vassilis GEKASCzech J. Food Sci., 2015, 33(2):126-136 | DOI: 10.17221/335/2014-CJFS We characterised 12 wines (10 red, 1 sweet red, and 1 white) from different Cypriot cultivars in terms of their phenolic, anthocyanin composition, and antioxidant capacity as determined by two activities: radical scavenging and ferric reducing ability. Two different phenolic fractions (tannin-free and 1-kDa permeate) were also isolated from Cypriot wines with an ultimate goal of investigating their role in the overall antioxidant capacity of wines. The results indicated that Maratheftiko and Lefkada cultivars had higher concentrations of o-diphenols, hydroxycinnamic acid derivatives, flavonols and anthocyanins compared to other Cypriot cultivars like Ofthalmo, Mavro, and Giannoudi. The higher concentrations of phenols did not always correspond to a higher antioxidant capacity, probably due to the antagonistic action observed between hydroxycinnamic acid derivatives, flavonols, and anthocyanins. The latest interactions restricted the release of flavonols' advanced antiradical activity in wines. |
Sensory evaluation of chocolate bar production materials of dry cocoa seeds in various fermentation treatmentsShort CommunicationNurhayati Nurhayati, Mulono ApriyantoCzech J. Food Sci., 2021, 39(1):58-62 | DOI: 10.17221/272/2020-CJFS The processing of chocolate bars is influenced by cocoa beans used. Chocolate bar is one of the downstream products with a simple processing process. The taste and aroma in candy comes from chocolate bars. Fermentation is an important activity in the formation of cocoa flavour. This study aims to determine the panellists' acceptance of chocolate bars produced from various fermentation treatments of sun-dried cocoa beans. The materials used in this study were cocoa beans of varieties of Lindak. The fermentation variation consisted of two treatments, namely, the addition of the inoculum gradually (A1) and the addition of the inoculum simultaneously at the beginning of fermentation (A2). The inocula added were Sacharomyces cerevisiae (FNCC 3056), Lactococcus lactis (FNC 0086) and Acetobacter aceti (FNCC 0016). The control treatment was dry cocoa beans without fermentation (A0). The fermentation time was 120 h, then the fermented cocoa beans were processed into chocolate bars. The resulting chocolate bars were subjected to sensory analysis including evaluation of the taste of sepia, bitter, and sour taste and in the test the polyphenol content of chocolate bars was used. The results showed that there was a decrease in the septic, bitter and sour taste from treatment A0, A2 and A1, respectively. The highest polyphenol content was in A0, A2, and A1, respectively. Panellists stated that the preferred chocolate bar was made from cocoa beans with A1 treatment. |
Influence of supercritical fluid extract of Cinnamomum zeylanicum bark on physical, bioactive and sensory properties of innovative cinnamaldehyde-enriched chocolatesFood Analysis, Food Quality and NutritionMuhammad Ahmar JAHANGIR, Aamir SHEHZAD, Masood Sadiq BUTT, Muhammad SHAHIDCzech J. Food Sci., 2018, 36(1):28-36 | DOI: 10.17221/237/2016-CJFS In the current investigation, the potential utility of cinnamaldehyde obtained from cinnamon (Cinnamomum zeylanicum) bark powder in enhancing the antioxidant capacity of dark chocolates was evaluated. To this end, the effects of conventional solvent extracts (CSE) and supercritical fluid extracts (SFE) on total phenolic contents, physical and sensory attributes of cinnamaldehyde-enriched chocolates were determined over the course of 60 days of storage. The addition of 0.5% nutraceuticalSFE and 1% nutraceuticalCSE extracts significantly increased the total phenolic contents of the chocolates to 15.62 ± 0.35 mg GAE/g and 13.31 ± 0.26 mg GAE/g in T2 and T1, respectively. In terms of texture (hardness), 0.5% extract resulted in softer chocolates (64.87 ± 2.41 N) as compared to the control (70.91 ± 2.83 N). At storage termination, colorimetric results revealed a whitening of the chocolate surface that resulted in incremental increases in L* and b*, whereas a* exhibited a declining trend. Moreover, the sensory results showed a better hedonic response for the enriched products. Taken together, cinnamaldehyde enrichment is beneficial for both the functional as well as oxidative stability of chocolates. Chocolate, as the most commonly craved food product, is gaining much attention from the manufactures as a potential vehicle for the delivery of functional health benefits. In this study, we used cinnamaldehyde and maltitol (sugar replacer) to prepare functional chocolates with a special emphasis on diabetic patients, an approach that will open new horizons for innovative product development. We also optimised and characterised the extraction conditions for bioactive components using green extraction technology, i.e. a supercritical fluid extraction technique which is cost-effective and environmentally friendly. |
Effects of storage and processing parameters on pasting properties of Ofada for production of boiled and mashed riceFood Technology and Economy, Engineering and Physical PropertiesOludare Olumuyiwa ADEKOYENI, Rahman AKINOSO, Adekola Felix ADEGOKE, Stephen Akintunde FAGBEMICzech J. Food Sci., 2018, 36(3):239-245 | DOI: 10.17221/121/2017-CJFS This study was designed to determine the effect of storage duration and processing conditions on pasting characteristics of Ofada rice and to determine the optimum pasting parameters for the production of boiled and mashed rice. The interactions of variables (storage, soaking, parboiling and drying) were studied using response surface methodology and pasting responses (final viscosity, trough, setback viscosity, breakdown, pasting temperature and pasting time) were analysed. The coefficient of R2 and adequate precision ranged between 0.994-0.7374 and 26.825-5.375, respectively, which indicate good fitness of the model. Parboiling temperature, drying temperature and storage duration significantly influenced the pasting properties of grain as revealed by positive coefficients in the model. The pasting requirements for boiled rice are storage of paddy for nine months, soaking for two days and 19 h, parboiling at 90.42°C and drying at 30°C, while for mashed rice storage of paddy for one month followed by soaking for five days, parboiling at 80°C and drying at 54.22°C are required. |
Effect of the dough mixing process on the quality of wheat and buckwheat proteinsFood Technology and Economy, Engineering and Physical PropertiesMarcela Sluková, Julie Levková, Alena Michalcová, Šárka Horáčková, Pavel SkřivanCzech J. Food Sci., 2017, 35(6):522-531 | DOI: 10.17221/220/2017-CJFS The changes in the structure of cereal proteins during the mixing of flour into dough was described and evaluated. Wheat gliadins and glutenins (gluten proteins) have unique physical properties and play an important role in breadmaking. The effect of mixing time on the formation and the structure of the gluten network was determined using scanning electron microscopy (SEM). Buckwheat flour (gluten-free) was used to compare the development of structure during the mixing process. |
Fruit juices with probiotics - new type of functional foodsFood Microbiology and SafetyŠárka HORÁČKOVÁ, Kristýna ROKYTOVÁ, Kristina BIALASOVÁ, Iveta KLOJDOVÁ, Marcela SLUKOVÁCzech J. Food Sci., 2018, 36(4):284-288 | DOI: 10.17221/39/2018-CJFS The cells of commercial strain Bifidobacterium animalis subsp. lactis Bb12 were encapsulated using emulsion encapsulation in a milk protein matrix. The volume based median of the microcapsules was 52.1 ± 6.2 µm. The stability of free and encapsulated cells was compared during 28 day-storage in pineapple juice and in strawberry-apple juice at 8 ± 1°C and 22 ± 1°C. Encapsulation ensured a higher number of cells compared to the free cells only at 8 ± 1°C. Strawberry-apple juice was found to be not suitable as probiotic vehicle. Both free and encapsulated cells lost their viability after 14 days at 22 ± 1°C. The number of bifidobacteria cells, pH and lactic and acetic acid content did not change in pineapple and strawberry-apple juice after 24 h cultivation at 37°C. |
Effect of different rice starches, inulin, and soy protein on microstructural, physical, and sensory properties of low-fat, gluten, and lactose free white saucesOriginal PaperLuis M. GUARDEÑO, José L. VÁZQUEZ-GUTIÉRREZ, Isabel HERNANDO, Amparo QUILESCzech J. Food Sci., 2013, 31(6):575-580 | DOI: 10.17221/483/2012-CJFS The microstructural, physical, and sensory properties of low-fat sauces made with different rice starches, soy protein ,and inulin were analysed in order to obtain sauces suitable for celiac and lactose intolerant consumers. Soy protein and inulin could prevent starch degradation due to their high water-binding capacity. Moreover, protein molecules could diffuse into the starch granules and soluble inulin could interact with starch polymers within the granule. Both effects would hinder amylose leaching. Inulin provides better diffusion capacity of gelatinised granules and soy protein-starch granule aggregates than sunflower oil, which helps to decrease viscosity in modified rice starch sauces. Soy protein prevents syneresis in the sauces. Inulin affects colour parameters in native rice starch sauces, probably because of inulin and retrograded amylose polymers interactions. Sauces made with sunflower oil and modified rice starch are best rated by consumers. However, according to the statistical analyses, the replacement of oil by inulin could be suitable to prepare low-fat, gluten, and lactose free white sauces when modified rice starch is used. |
Fungal contamination spices from Indonesia with emphasis on Aspergillus flavusFood Microbiology and SafetyKiki Nurtjahja, Cut Fatimah Zuhra, Helmina Sembiring, Aditiya Bungsu, Jesica Simanullang, Juwita Esterina Silalahi, Betriana Novi Lenta Gultom, Sartini SartiniCzech J. Food Sci., 2019, 37(5):338-344 | DOI: 10.17221/18/2019-CJFS Filamentous fungi were isolated from ten spices collected from markets in Indonesia. The aim was to enumerate fungal contamination and to determine the toxigenicity of Aspergillus flavus strains on each of the spices. Viable fungal populations were determined using a dilution method. Toxigenicity of Aspergillus flavus was determined by culture on a quick screening coconut agar and by PCR using four sets of primers specific for aflatoxin pathway genes. All the tested spices were contaminated by storage fungi, Species of Aspergillus was the most commonly isolated moulds followed by species of Fusarium, Mucor, Penicillium and Rhizopus. The greatest number of Aspergillus flavus isolates were found on white pepper, followed by nutmeg, cardamom, and black pepper. The greatest number of Aspergillus chevalieri isolates were found on coriander, followed by nutmeg. Fifty strains of A. flavus were isolated, all of the strains produced large sclerotia and biseriate conidiophores. Their toxigenicity was assayed by the presence of yellow pigment on a quick screening coconut agar medium and PCR amplification of regulatory and structural genes in the aflatoxin pathway. |
Reduction in sodium chloride content in saltine crackers through an edible coatingOriginal PaperCrislayne Teodoro Vasques, Maiara Pereira Mendes, Denise de Moraes Batista da Silva, Antonio Roberto Giriboni MonteiroCzech J. Food Sci., 2020, 38(4):237-241 | DOI: 10.17221/221/2019-CJFS Aiming to reduce the sodium content in saltine crackers, the present study employed a methodology of salt coating that provided an inhomogeneous distribution of salt so that the salt perception was not altered. To this end, three cracker recipes were prepared and compared. Recipe 1 (F1) was the standard, Recipe 2 (F2) had a 33.3% reduction in salt in the dough, and Recipe 3 (F3) had no salt in the dough but instead a salty coating with the same amount of salt as F2. Physicochemical and sensory analyses revealed that F1 and F3 were not statistically different in salt perception, whereas F2 differed from the others. From these results, it was concluded that the methodology of covering crackers with a salty coating with a 42.5% salt reduction could be an alternative to achieving salt reduction. |
Components responsible for antimicrobial activity of propolis from continental and Mediterranean regions in CroatianFood Microbiology and SafetyIvana Tlak Gajger, Iva Pavlović, Mirza Bojić, Ivan Kosalec, Siniša Srečec, Toni Vlainić, Josipa VlainićCzech J. Food Sci., 2017, 35(5):376-385 | DOI: 10.17221/103/2017-CJFS Propolis is a popular subject of research worldwide due to its therapeutic potential. The antimicrobial activity of propolis appears to be promising but depends on many variables related to its origin such as the content of phenolics and flavonoids. To address this issue with Croatian propolis, which has two major origins (Mediterranean and continental), we exposed bacteria (Escherichia coli and Staphylococcus aureus) and yeasts (Candida albicans and Aspergillus niger) to different propolis concentrations (two-fold microdilution method with TCC/formazan endpoint). Total phenolic and flavonoid content and chromatographic profile along with antioxidant activity were assessed. The majority of the 24 propolis samples tested exhibited potent antimicrobial activity against S. aureus bacteria and the yeast C. albicans. Most propolis samples also exhibited robust antioxidative capacity which correlated polyphenol and flavonoid content. To the best of our knowledge this is the first study in which the antimicrobial activity of Croatian propolis is correlated with its constituents. |
Investigation of hepatitis A and E viruses in mussels collected from the Bosphorus, in Istanbul, Turkey - short communicationFood Microbiology and SafetyHuseyin YILMAZ, Utku CIZMECIGIL, Eda Altan TARAKCI, Ozge AYDIN, Aysun YILMAZ, Mehmet CALICIOGLU, Gurhan CIFTCIOGLU, Ali AYDIN, Kamil BOSTAN, Tansel SIRELI, Mine GUZEL, Asiye KARAKULLUKCU, Bekir KOCAZEYBEK, Wim van der POEL, Juergen RICHT, Nuri TURANCzech J. Food Sci., 2018, 36(3):215-220 | DOI: 10.17221/233/2017-CJFS Hepatitis A and E viruses (HAV and HEV) are recognised as food- and water-borne infections and shellfish are a well-documented source of these viruses. The presence of HAV and HEV in mussels has not previously been investigated in Bosphorus, Istanbul, Turkey, and therefore the aim of this study was to investigate the frequency of HAV and HEV in mussels collected from this location. A total of 92 pooled samples representing 736 mussels originating along the Bosphorus coast were collected from fish distributors. RNA was extracted using the RNeasy Plant Mini Kit and a TaqMan real-time RT-PCR was performed using primers specific to HAV and HEV. Amongst the 92 pooled samples tested, 3 (3.3%) were found to be positive for HAV by the TaqMan real-time RT-PCR. No HEV was detected in any of the mussels tested. A 174 bp product was observed on gel electrophoresis with HAV positive samples detected by SYBR Green real-time PCR after reverse transcription. This product was sequenced and confirmed to contain HAV sequences by alignment using the data in GenBank. This is the first report describing the presence of HAV in mussels harvested in the Bosphorus, Istanbul, Turkey, indicating the potential contamination of aquatic environment and risk to public health. |
Antioxidant properties and resveratrol content of Polish Regent wines from Podkarpacie regionFood Analysis, Food Quality and NutritionSabina Bednarska, Aneta Dabrowa, Joanna Kisala, Idalia KasprzykCzech J. Food Sci., 2019, 37(4):252-259 | DOI: 10.17221/222/2018-CJFS The antioxidant properties of cool-climate Regent wines from Podkarpacie region, Poland were investigated. Total polyphenols, total flavonoids, total monomeric anthocyanins, trans-resveratrol concentration, radical scavenging ability using 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and total antioxidant capacity with TEAC and FRAP methods were measured. The average contents of the compounds determined for Regent wines were comparable to the respective data available in literature found for warm-climate wines. Correspondence Analysis of the data revealed the relation of total polyphenols content and antioxidant capacity and radical scavenging ability of studied wines, and in lesser extent correlation with total flavonoids content. The total monomeric anthocyanins content and resveratrol concentration were poorly related to the total polyphenols content and antioxidant capacity. |
Determining the optimal method for DNA isolation from fruit jamsFood Microbiology and SafetyTereza SOVOVÁ, Barbora KŘÍŽOVÁ, Jaroslava OVESNÁCzech J. Food Sci., 2018, 36(2):126-132 | DOI: 10.17221/340/2017-CJFS DNA extraction is a crucial step in PCR analysis especially when analysing food samples that can be degraded and can potentially contain PCR-inhibiting substances. In this study, we compared the suitability of three DNA extraction methods - two kits: DNeasy® Plant Mini Kit and NucleoSpin® Food, and the CTAB method - for DNA extraction from commercial fruit jams. Fourteen jams with different contents of fruit, sugar and other additives were extracted in triplicate using the above-mentioned methods directly and after a washing step. The concentration and optical density were analysed using UV spectrophotometry and the amplifiability of the obtained DNA was evaluated using a PCR assay targeting a sequence coding for chloroplast tRNA-Leu. Samples isolated using the NucleoSpin® Food kit contained non-amplifiable DNA in eight cases, and samples isolated using the CTAB method could not be quantified. The DNeasy® Plant Mini Kit thus proved to be the most suitable method, since well-amplifiable DNA was obtained for all the analysed samples. |
The methods analysis of hazards and product defects in food processingFood Analysis, Food Quality and NutritionKrzysztof PrzystupaCzech J. Food Sci., 2019, 37(1):44-50 | DOI: 10.17221/44/2018-CJFS The paper pertains to the issue of quality assurance methods. Particular emphasis is placed upon the examination of hazards and possible product defects in food processing. At present, Polish regulations oblige any food processing entity to implement HACCP system. The system is perceived as a universal vaccine preventing the emergence of possible hazards or reducing the risk to an acceptable level. As far as defects are concerned, these are either disregarded altogether or do not occur at all. Meanwhile, the practice proves the case is not so. The research aspect of the paper revolves around an attempt to transplant solutions primarily applied in the automotive sector onto food processing industry. The practical aspect of the paper is manifested in the analysis of causes behind defects and hazards conducted on the basis of bakery industry. Potential hazards and product defects emerging from the process were identified in the course of the study. In addition, in order to eliminate these, their level was established with the application of various methods. |
A targeted analysis of flavonoids in asparagus using the UPLC-MS techniqueOriginal PaperMing Zhang, Guihong Zhao, Guisheng Zhang, Xinyang Wei, Mingxia Shen, Liping Liu, Xiangying Ding, Yong LiuCzech J. Food Sci., 2020, 38(2):77-83 | DOI: 10.17221/168/2019-CJFS Production development for asparagus has become an important research subject due to its low shelf life. In order to determine the content of flavonoids in asparagus tips and shoots, LC-MS-based method was performed for a targeted analysis of flavonoids in asparagus, and 34 peaks attributed to the targeted flavonoids were characterised. Twelve peaks corresponding to rutin, isoquercitrin, quercetin, naringin, taxifolin, vitexin, genistin, daidzein, luteolin, chrysin, and kaempferide were identified and quantified from the asparagus tips and shoots by the LC-MS-based detection with monitoring of parent/daughter ions. The results showed that rutin (> 99%) was the main flavonoid present in the asparagus tips and shoots. Although the tips and shoots contained almost similar compounds, the content of the major compounds, especially rutin, was significantly different. Therefore, the method established through this study could be used for quantitative analysis of flavonoids, especially rutins, in asparagus. The result will provide a theoretical basis for food development in asparagus. |
l-Ascorbic acid content and antioxidant capacity in less-known fruit juicesFood Analysis, Food Quality and NutritionIvo Soural, Petr Šnurkovič, Monika BieniaszCzech J. Food Sci., 2019, 37(5):359-365 | DOI: 10.17221/305/2018-CJFS Eight less-known juices are characterised and contents are monitored of selected substances and nutritional parameters. 100% juices were produced of Aloe Vera, Aronia, Blackcurrant, Black elder, Cranberry, Malpighia, Pomegranate and Seaberry by pressing, including the flesh. Total phenolic compounds (TPC) and ascorbic acid (AA) content were analysed as other parameters. The juices were measured on total antioxidant capacity (TAC) as the content of trolox, where the highest levels were found for Malpighia 63.2 mM, when the value was significantly different (P < 0.05) compared with all the other juices, while Aloe Vera had lowest levels with 0.4 mM. The Aronia juice possessed the highest level of TPC (8297 mg of GAE/l). TAC levels very well corresponded with TPC levels while AA content actually did not correlate with TAC values. In addition to the objective analysis, the juices were subjected to a sensory evaluation. Blackcurrant presents an attractive product from the sensorial aspect as well as in terms of the nutritional value. |
Onion waste as a rich source of antioxidants for meat productsFood Technology and Economy, Engineering and Physical PropertiesJan Bedrníček, Ivana Laknerová, Zuzana Linhartová, Jaromír Kadlec, Eva Samková, Jan Bárta, Veronika Bártová, Jan Mráz, Milan Pešek, Renata Winterová, Naděžda Vrchotová, Jan Tříska, Pavel SmetanaCzech J. Food Sci., 2019, 37(4):268-275 | DOI: 10.17221/68/2018-CJFS Onion skin is a waste produced in thousands of tons annually in the European Union. It is a rich natural source of flavonoids and its water extracts (as an environmentally friendly solvent) could be used as an antioxidant material for meat products. Therefore, antioxidant properties of onion skin water extracts (OSWEs) were tested on cooked pork patties. Pork patties were divided into five treatments: control (no antioxidant), 10 and 20% (w/w) of yellow OSWE, and 10 and 20% (w/w) of red OSWE. Antioxidant activity, total polyphenols, thiobarbituric acid reactive substances (TBARS), and sensory analysis were assessed. Patties with added antioxidants showed significantly (P < 0.05) higher antioxidant activity and total polyphenol content. Samples with OSWEs, after 5-day storage (5°C), had significantly (P < 0.05) lower TBARS values compared to control. Two main phenolic compounds were identified in OSWEs by liquid chromatography - mass spectrometry using electrospray ionisation in negative mode: quercetin (m/z 301) and quercetin monoglucoside (m/z 463). OSWEs demonstrated the potential to be used as a source of natural antioxidants with strong antioxidant activity in meat products. |
Acceptance of bars with edible insects by a selected group of students from Tri-City, PolandOriginal PaperJoanna Bartkowicz, Ewa Babicz-ZielińskaCzech J. Food Sci., 2020, 38(3):192-197 | DOI: 10.17221/236/2019-CJFS Although entomophagy as a diet has been known since the dawn of humanity, it is still considered a novelty to the European market and consumers. This study was performed to evaluate the acceptance of a trend promoted by the FAO diet regarding selected young Polish consumers and it presents the results of a survey conducted among them. The primary goal of this study was to assess the acceptance of new edible insect products with mealworms Tenebrio molitor L. and house crickets Acheta domesticus L. These products were prepared in the form of four different types of bars; one without insects, one with whole mealworms, one with ground mealworms and one with ground crickets. According to consumers, the worst bars were the ones which contained the whole mealworms. Additionally, the main problems with accepting this product were caused by the colour of the ground crickets and visible whole pieces of the insects in the edible bars. The study proved that the acceptance of insect bars as food depends on the tastiness and smell. The acceptance of bars also depends on variants. The basic bar had the highest acceptance rate, while the bar with whole mealworms had the lowest one. |
Efficacy of chemical agents and power ultrasound on biofilms formed by Asaia spp. - spoilage bacteria in beverage industriesFood Microbiology and SafetyIveta Šístková, Iveta Horsáková, Miroslav Čeřovský, Helena ČížkováCzech J. Food Sci., 2019, 37(4):221-225 | DOI: 10.17221/235/2018-CJFS Spoilage bacteria were isolated from spoiled fruit-flavoured bottled water with a visual defect in the form of floating flocks. The bacteria were identified as Asaia lannensis using the PCR technique. The efficacy of five chemical agents commonly used in the beverage industry and of power ultrasound (PUS) on Asaia biofilms was studied. A static cultivation procedure on stainless steel plates was used and the efficacy of the chemical agents was tested in two stages. First, only the chemical agents were used. Second, the effect of the application of PUS for 1 min prior to the application of the chemical agents was tested. The most effective chemical agent was the one based on peracetic acid. Its use without PUS proved to be more effective than a combination of any of the other chemical agents with PUS. The least effective methods included the physical sanitation by PUS, the chemical agent based on a 10% solution of sodium hypochlorite and sodium hydroxide, and the chemical agent containing a 0.3% solution of chlorine dioxide. |
Chemical composition, safety and quality attributes of traditional cottage sausageFood Chemistry and SafetyKrzysztof Surówka, Ireneusz Maciejaszek, Kamila Walczak, Maria Walczycka, Barbara Surówka, Magdalena Rzepka, Joanna BanaśCzech J. Food Sci., 2019, 37(5):325-331 | DOI: 10.17221/135/2019-CJFS The characteristic features of traditional cottage sausage were analysed. In addition, the extent to which manufacturers create product diversity on the market was investigated, along with potential health risks of the product to consumers. The samples had high overall sensory scores. The average level of fat slightly exceeded 28%, cholesterol content was in the range of 435.4-1220.3 mg/kg and salt content was 1.53-2.77%. Some manufacturers do not cure their product, but about 20% of them apply nitrites above the level of 150 mg/kg. Due to their relatively high pH level (5.76-6.60) and water activity (0.95-0.98), Polish cottage sausage can be a medium which encourages the growth of microorganisms; however, pathogenic bacteria were not found. Histamine was detected in only 42% of the samples, at the low level of 2.6 to 34.2 mg/kg. Principal Component Analysis (PCA) was applied and the dominant variables were specified for particular PCs. |
Volatile organic compounds throughout the manufacturing process of Mozzarella di Gioia del Colle PDO cheeseOriginal PaperGiuseppe Natrella, Giuseppe Gambacorta, Michele FacciaCzech J. Food Sci., 2020, 38(4):215-222 | DOI: 10.17221/129/2020-CJFS The evolution of volatile organic compounds during the production process of Mozzarella di Gioia del Colle (traditional type) was investigated in comparison with citric mozzarella (industrial type). The total volatile concentration in the traditional curd was ten times higher than milk, versus only twice as much in the industrial type. In both technologies, the concentrations decreased from curd to mozzarella at the same rate, due to losses during the stretching phase. The higher microbial activity in the traditional product was responsible for a much more complex profile, characterised by 2- and 3-methylbutanal, acetoin, ethanol, 3-methyl-1-butanol, acetic acid and ethyl-acetate. In contrast, the industrial mozzarella had a very simple profile, with the most important compounds being directly derived from the milk, the oxidation reactions, or the activity of the adventitious microflora such as acetone, hexanal, nonanal, and hexanoic acid. According to the discriminant analysis, Mozzarella di Gioia del Colle had a very different profile than the milk used, whereas the industrial mozzarella was more similar to the milk. |
The application of NIR spectroscopy in moisture determining of vegetable seedsShort CommunicationJonna Szulc, Grażyna Gozdecka, Wojciech PoćwiardowskiCzech J. Food Sci., 2020, 38(2):131-136 | DOI: 10.17221/57/2019-CJFS The aim of the study was to elaborate a universal calibration for the near infrared (NIR) spectrophotometer to determine the moisture of various kinds of vegetable seeds. The research was conducted on the seeds of 5 types of vegetables - carrot, parsley, lettuce, radish and beetroot. For the spectra correlation with moisture values, the method of partial least squares regression (PLS) was used. The resulting qualitative indicators of a calibration model (R = 0.9968, Q = 0.8904) confirmed an excellent fit of the obtained calibration to the experimental data. As a result of the study, the possibilities of creating a calibration model for NIR spectrophotometer for non-destructive moisture analysis of various kinds of vegetable seeds was confirmed. |
White lupin (Lupinus albus L.) - nutritional and health values in human nutrition - a reviewReviewJanusz PrusinskiCzech J. Food Sci., 2017, 35(2):95-105 | DOI: 10.17221/114/2016-CJFS White lupin seeds have been used in human nutrition and treatment for several thousand years. Nowadays the use of white lupin seeds is limited by a small scale of their production. However, in the last 20 years quite new properties of white lupin have been discovered for the application in the production of different kinds of functional food. Unique traits of protein, fatty acids with a desirable ratio of omega-6 to omega-3 acids, and fibre as well as other specific components, for example oligosaccharides and antioxidants or non-starch carbohydrates, make white lupin an excellent component in many healthy diets. The effects of white lupin components concern the physiological condition of the human body, including diabetes, hypertension, obesity, cardiovascular diseases, lipid concentration, glycaemia, appetite, insulin resistance, and colorectal cancer. Seeds are used among others for the production of gluten-free flour, bacterial and fungal fermented products, noodle and pasta products, as substitutes of meat, egg protein and sausages, also are cooked, roasted and ground and mixed with cereal flour in the production of bread, crisps and pasta, crisps and dietary dishes. |
Influence of different essential oils on refrigerated fish patties produced from bonito fish (Sarda sarda Bloch, 1793)Food Analysis, Food Quality and NutritionHusnu Sahan GURAN, Gulsum OKSUZTEPE, Ozlem Emir COBAN, Gokhan Kursad INCILICzech J. Food Sci., 2015, 33(1):37-44 | DOI: 10.17221/188/2014-CJFS The effects of different concentrations of thyme (group T), clove (group Cl), and rosemary (group R) extracts on the microbiological, chemical, and sensory attributes of fish patty made from the bonito fish (Sarda sarda Bloch, 1793) were investigated. The numbers of total mesophilic aerobic bacteria, coliform bacteria, Staphylococcus-Micrococcus spp. and yeasts and moulds in group R were lower than those of the other groups during storage (P < 0.05). During the storage period, total volatile basic nitrogen (TVB-N), thiobarbituric acid index (TBA-i), peroxide values, and free fatty acid content gradually increased in all groups, and significant differences were found between the groups (P < 0.05). The results of sensory evaluation showed that the shelf life of fish patties was 4 days for the control group, and 8, 10, and 14 days for the groups treated with thyme, clove and rosemary essential oil, respectively (P < 0.05). In conclusion, the addition of essential oils showed a positive effect on the product shelf-life; and in particular, rosemary essential oil produced a remarkable effect. |
Effect of solvents and extraction methods on total anthocyanins, phenolic compounds and antioxidant capacity of Renealmia alpinia (Rottb.) Maas peelFood Technology and Economy, Engineering and Physical PropertiesJavier David Vega Arroy, Hector Ruiz-Espinosa, Juan Jose Luna-Guevara, Maria L. Luna-Guevara, Paola Hernández-Carranza, Raúl Ávila-Sosa, Carlos Enrique Ochoa-VelascoCzech J. Food Sci., 2017, 35(5):456-465 | DOI: 10.17221/316/2016-CJFS The effect of different solvents and extraction methods on total anthoc yanins, phenolic compounds, and antioxidant capacity from x´kijit (renealmia alpinia Rottb. Maas) peels was evaluated. In order to evaluate the effect of solvents on the bioactive compounds extraction efficienc y and antioxidant capacity, a special cubic mixture design model was implemented with ethanol, methanol, and acetone as solvents and conventional (agitation - 1 and 6 h; Soxhlet - 2 and 4 h), novel (power ultrasound - 2.5 and 5 min) methods, and combination of extraction methods. Acceptable correla - tions between predicted and experimental data were obtained for total anthoc yanins ( r2 = 0.95), phenolic compounds (r2 = 0.78), and antioxidant capacity (r2 = 0.97), with methanol exhibiting the highest extraction yield of bioactive compounds and resultant antioxidant capacity. Although the extraction of total anthocyanins (82.2-85.8 mg cyanidine/ kg) and phenolic compounds (183.6-207.0 mg GAE/kg) was best carried out through Soxhlet, the ultrasonic treat- ment showed similar antioxidant capacity values (27.4-34.3 mg Trolox/kg) to those of 2-h Soxhlet. Moreover, a 5-min ultrasound pretreatment significantly increased (p < 0.05) phenolic compounds by 11, 21 and 12% when combined with agitation 1, 6, and 2-h Soxhlet treatments, respectively ; while the antioxidant capacity increased by 26, 48, and 22% for the same treatments. Ultrasound might be used as a valuable, green alternative procedure for improving the solvent extraction of bioactive compounds. |
Ferulic acid in cereals - a reviewReviewHüseyin BOZCzech J. Food Sci., 2015, 33(1):1-7 | DOI: 10.17221/401/2014-CJFS Phenolic acids represent the most common form of phenolic compounds in the cereal grain and many other plants. The phytochemical ferulic acid is found in the leaves and seeds of many plants, but especially in cereals. It is the most abundant phenolic acid in common cereals, representing up to 90% of total phenolic compounds. Ferulic acid has been reported to have many physiological functions, including antioxidant, antimicrobial, anti-inflammatory, and anti-cancer activities. It is an antioxidant which neutralises free radicals (superoxide, nitric oxide, and hydroxyl radical) which could cause oxidative damage to cell membranes and DNA. Like many other antioxidants, ferulic acid reduces the level of cholesterol and triglyceride, thereby reducing the risk of heart disease. |
The influence of gamma-irradiation on the formation of free radicals and antioxidant status of oregano (Origanum vulgare L.)Jana Horváthová, Milan Suhaj, Martin Polovka, Vlasta Brezová, Peter ŠimkoCzech J. Food Sci., 2007, 25(3):131-143 | DOI: 10.17221/741-CJFS The influence of various gamma-radiation dose absorptions on oregano (Origanum vulgare L.) solid samples was monitored by means of electron paramagnetic resonance (EPR) spectroscopy. Further, the antioxidant activity of oregano methanol/water extracts was characterised using DPPH (1,1-diphenyl-2-picrylhydrazyl free radical); thiobarbituric acid reactive substances (TBARS); ferric reducing power (FRP); and total content of phenolic compounds (TPC) assays. EPR spectroscopy was used for the investigation of the influence of the absorbed dose on the character of the paramagnetic structures formed, as well as for their thermal stability and life-time characterisation. EPR spectrum of the reference (non-irradiated) sample represents a broad singlet line with unresolved hyperfine splitting, attributable to Mn(II) ions, upon which the additional sharp EPR signal (g = 2.0022, ΔBpp ≈ 1 mT) is superimposed, assigned to stable semiquinone radicals produced by the oxidation of polyphenolic compounds present in plants. The additional paramagnetic structures of different origin (mostly of cellulose and carbohydrate), possessing diverse thermal stability and life-time, were identified in the gamma-irradiated samples. Immediately after irradiation, a statistically significant increase was observed of the TBARS values and the total content of phenolic compounds in methanol/water oregano extract. The alterations of the antioxidant properties of oregano extracts with the time after the radiation treatment were also monitored. A substantial time-dependent decrease of antioxidant activity was observed, probably as a result of storage, with both irradiated and non-irradiated oregano samples, as obvious from the ferric reducing power test and the content of total phenolic substances. The influence of irradiation and subsequent storage of oregano samples on the DPPH radical-scavenging ability was only negligible. |
Qualitative properties of pasta enriched with celery root and sugar beet by-productsFood Technology and Economy, Engineering and Physical PropertiesLucia MINAROVIČOVÁ, Michaela LAUKOVÁ, Zlatica KOHAJDOVÁ, Jolana KAROVIČOVÁ, Dominika DOBROVICKÁ, Veronika KUCHTOVÁCzech J. Food Sci., 2018, 36(1):66-72 | DOI: 10.17221/242/2017-CJFS The effects of wheat flour replacement at different levels (5, 7.5, 10, and 20%) by celery root and sugar beet pulp powder on rheological parameters and quality properties of enriched pasta were studied. Sensory evaluation was also investigated. Incorporation of fibre powders increased water absorption and prolonged dough stability and dough development time. Enriched pasta had higher moisture content than control pasta. Addition of fibre powders also modified the cooking quality of pasta (cooking loss and water absorption were increased and optimal cooking time was reduced). Moreover cooked pasta with the higher addition level of celery root powder was characterised by higher intensity of vegetable taste and had pleasant flavour and colour. Sensory evaluation showed that pasta with the addition of 7.5% celery root powder was the most acceptable for assessors. |
