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The series of phenolic acid (2-, 3-, 4-monohydroxy- and 2,4-, 2,5-dihydroxy) alkyl esters (methyl, ethyl, propyl, and butyl) were prepared, and their antimicrobial activities were determined. The antimicrobial activity against the tested microorganisms Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus brasiliensis was investigated and expressed by minimum inhibitory concentration (MIC) in the range of 1.2-20 mM. The inhibitory activity of higher esters of phenolic acids was found to be higher than that of methyl esters and acids. The minimum inhibitory concentration (MIC) of tested compounds was compared with that of 4-hydroxybenzoic acid and its esters (parabens).

This study aimed to produce yogurt with Ganoderma lucidum residues and selected probiotic bacteria. To select the most potent GABA-producing strain (GABA - γ-aminobutyric acid), nine probiotic bacteria were subjected to the glutamate decarboxylase (GAD) activity assay. Limosilactobacillus reuteri DSM 17938 was selected and used in preparing fresh yogurts, with and without supplementation of Ganoderma residues obtained after water extraction [GW (Ganoderma waste) 2% (w/v)]. A decrease in pH during fermentation and the occurrence of syneresis were investigated. Lactic acid bacteria (LAB) viability and anti-Escherichia activity were estimated. Further, the cytotoxic effect of yogurt extracts on the human colon cancer cell line (HCT116) was surveyed. Besides functionality, the sensory attributes were evaluated. The pH values did not significantly change with the GW addition while increasing the LAB counts [up to 9.76 ± 0.11 log colony-forming units (CFU) mL^-1] and the cytotoxic effect on HCT116 cells. Yogurt produced with selected bacteria and GW had the most valuable anti-coli effect against E. coli 0157: H7 and E. coli ATCC 35218 (American Type Culture Collection, Rockville, Maryland) (4.81 ± 0.62 and 5.64 ± 0.29 CFU mL^-1, respectively). Although the added GW increased the yogurt functionality, it had a slightly negative effect on the taste and texture of the partially modified recipe. Yogurts fortified with GABA-producing strain and GW could potentially reduce relapse rates of depressive disorders.

The prospects of sparkling wine production by the 'Champenoise' method using alginate-immobilised yeast cells were examined. Grape varieties dominant in quantity were selected within the group of recommended and permitted varieties of Kutjevo vineyards, located in the eastern part of continental Croatia. Research revealed that there are no influential variations in the principal physicochemical and sensory characteristics between sparkling wines obtained through immobilised yeast and traditional sparkling method. The analysis of aroma compounds showed minor differences between samples. Observed oenological parameters assessed in the final products did not show any relevant oenological differences, with the exception of alcohol content, which was slightly higher in sparkling wines made with yeast cells immobilised with calcium alginate beads. According to this research, the sensory properties of the produced sparkling wines, compared to sparkling wine produced with free yeast, did not show any significant differences. On the full-scale obtained results indicate that some of the selected varieties can be sorted as suitable for the production of sparkling wine using immobilised yeast cells.

Ten beaver (Castor fiber) females were used in the experiment. The samples were excised from a different anatomical location of each beaver carcass used in the study: m. longissimus dorsi (LD), m. triceps brachii (shoulder), m. biceps femoris (thigh). Thigh muscles were characterized by the highest percentage of free fat followed by longissimus muscle and shoulder. The total proportions of saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA), including many individual fatty acids, were affected by the muscle anatomical location. The fattiest thigh had the most favourable and highest PUFA/SFA, hypocholesterolemic/hypercholesterolemic (h/H) and lowest n-6/n-3 PUFA ratios, and the lowest thrombogenic index. Despite the fact that the leanest m. triceps brachii had the highest proportions of total polyunsaturated fatty acids, the n-6/n-3PUFA ratio was the lowest compared with the muscles from other anatomical locations and showed lower atherogenic index compared with a more fatty longissimus muscle.

To investigate a comparative evaluation of the gluten polymerization properties at different oil contents during the extrusion processing, the electrophoretic profiles of the gluten, free sulfhydryl (SH) compounds, the secondary structure of gluten, glutenin macropolymer contents and gluten network were measured. Five gluten samples were formulated by adding different oil contents. The low molecular weight contents of gluten decreased as well as the high molecular weight contents increased during the extrusion processing. The free SH of gluten at 8 or 10% oil content drops significantly to a minimum. The β-sheets contents of gluten have significantly difference between the treatments and control, except for 15 and 20% oil content treatments. Confocal laser scanning microscopy of mixed glutens correlated to the degree of oil contents with the gluten in the bi-continuous gluten network.

The investigation determined the influence of Lactobacillus helveticus strains (T80, T105, B734 and DSMZ 20075) and Lactobacillus acidophilus La-05 (probiotic strain) on the antioxidant activity of whey and milk protein preparations. In order to indicate possible mechanism of antioxidant activity of the obtained hydrolysates, the reducing power (RP) assay, ability to neutralize free radicals and Fe2+ chelating activity analysis were employed. The results suggest that antioxidant activity of tested hydrolysates depends on the type of protein preparation (substrate) and the applied bacterial strain. The strongest antioxidant activity was exhibited by whey protein isolate hydrolysate obtained by using L. helveticus T80. A majority of fermented products obtained with the use of the probiotic strain were characterized by higher antioxidant properties than those obtained by application of L. helveticus. The solution of caseinoglicomacropeptide fermented by strain T105 exhibited the highest RP values, while α-lactalbumin hydrolysed by probiotic strain (La-5) was characterized by the strongest Fe2+ chelating activity. The analysed protein preparations and their hydrolysates obtained with using tested bacteria might potentially be applied in food products in order to inhibit oxidation processes.

The gluten content in oat products on the market in the Czech Republic was monitored. The ELISA kit Ridascreen gliadin from R-Biopharm based on the R5 antibody was used for the gliadin determination. Oat products (41 samples), including 21 samples of oat flakes, were tested. Only 6 samples were labelled as gluten-free and it was confirmed that these samples meet the criteria for gluten-free foods. The total of 29 oat products, of which 15 were samples of oat flakes, contained more than 20 mg/kg of gluten. This means that 71% of oat cereal products were contaminated with cereals toxic for people with celiac disease. It was shown that most oat products on the Czech market are not safe for people with gluten intolerance.

In order to study the formation and conversion of the most important flavour compounds, the real wort used in alcohol-free beer fermentation was mimicked by a complex model medium containing glucose, yeast extract, and selected aldehydes. The fermentation experiments were carried out in a continuously operating gas-lift reactor with brewing yeast immobilised on spent grains (brewing by-product). During the continuous experiment, parameters such as oxygen supply, residence time (Rt), and temperature (T) were varied to find the optimal conditions for the alcohol-free beer production. The formation of ethanol, higher alcohols (HA), esters (ES), as well as the reduction of aldehydes and consumption of glucose were observed. The results suggest that the process parameters represent a powerful tool in controlling the degree of fermentation and flavour formation brought about by immobilised biocatalyst. Subsequently, the optimised process parameters were used to produce real alcohol-free beer during continuous fermentation. The final product was compared with batch fermented alcohol-free beers using the methods of instrumental and sensorial analysis.

Celiac disease is a gluten-sensitive entheropathy. Later studies suggest an increasing prevalence of that disease, likely due to the development of more sensitive methods of screening. Cereals containing prolamins such as wheat, rye, barley, and oat are toxic for celiac patients, whereas corn, rice, sorghum and buckwheat are considered to be safe. The reaction to gluten ingestion by patients suffering from that chronic disease is inflammation of the small intestine leading to the malabsorption of several important nutrients, vitamins and minerals, especially of calcium and iron. Osteopenia and osteoporosis are a frequent complication accompanying coeliac disease. The only effective treatment for coeliac disease is a long-life strict adherence to a gluten-free diet. Up to now, research studies related to gluten free bakery products have been focused on the design of gluten free matrixes by combining different starches and gluten free cereals. However, no special attention has been paid to the use of those products as carriers or vehicles of micronutrients, which are necessary for celiac patients. The aim of the research was to design of gluten free formula fortified with calcium destined to bake a bread. In that order the available organic or mineral calcium supplements were analysed. Optimisation of the technological parameters, analysis of chemical and minerals composition, sensory quality and texture of bread crumb were analysed. Preliminary estimation of bread colour, odour and taste allowed to select calcium caseinate and calcium citrate as supplements affecting beneficially the sensory quality of bread. When the mixture of both of them was applied, the improvement of bread porosity and structure was also observed. Based on the sensory evaluation of bread carried out with the method of sensory profiling and in hedonic tests gluten free bread fortified with a mixture of calcium caseinate and citrate was selected as the best. Texture properties of fresh gluten free bread crumbs fortified with calcium supplements measured using compression device of Instron were considerably improved. Summarising, the application of calcium supplements such as calcium caseinate and citrate in order to fortified gluten free bread with calcium influence beneficially its sensory and nutritional properties simultaneously enhancing the structure and texture of bread.

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.

The effects were evaluated of different factors on the level of spontaneous (SPO) and induced (IND) lipolysis as defined by the content of free fatty acids (FFA) in milk. Milk samples were collected at monthly intervals throughout the year from both morning and evening milkings either individually in a milking parlour (SPO; n = 10) or from the bulk tank (IND; n = 10). The data were analysed using SAS 9.1. More intensive SPO was observed from March to May with higher FFA contents (+0.034 to +0.523 mmol/100 g of fat; P < 0.05-0.01), and also from September to November (+0.077 to +0.292 mmol/100 g of fat; P < 0.05). More intensive SPO was also detected in the evening milk than in that coming from morning milking (+0.062 to +0.556 mmol/100 g of fat; P < 0.05-0.01). SPO measured immediately after milking was affected by the season and time of milking. The content of FFA characterising IND in bulk milk (0.33-1.10 mmol/100 g of fat) was higher (P < 0.05-0.001) than that due to SPO in individual samples (0.21-0.86 mmol/100 g of fat), especially in those from evening milking compared to morning milking (+0.10 to +0.47 vs. +0.12 to +0.22 mmol/100 g of fat; P < 0.05-0.001).

Spring barley varieties Tolar and Marthe were grown under the standard conditions and stress conditions with a combined effect of high temperature and drought in three experiments conducted in the greenhouse of phytotron type. The results showed that growing under the stress conditions led to reduced yield, grain quality and malt quality. This effect was observed both in the individual years and on average for the entire study period. Average yield of grain declined by ca 53% and retention above 2.5 mm screen decreased by ca 28% (P = 0.001). Further, average content of proteins rose by 3.7% while starch content decreased by 5.1% (P = 0.01). In malt samples, average extract and friability were reduced by 5.8% and 15%, respectively, and average protein content increased by 3.8% (P = 0.01). The growing conditions were a dominant factor in the conducted experiments.

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.

The aim of the study was to examine the contents of nitrates and nitrites in raw beef coming from cattle of the Polish Holstein-Friesian breed, black-and-white type, originating from different parts of Poland. The research material comprised semitendinosus and longissimus thoracis muscles obtained from 176 heads of cattle. The content of nitrites in the examined muscles ranged from 0.6 to 13.3 mg kg^-1 in rump muscles and from 0.8 to 13.7 mg kg^-1 in muscles of the back. The most samples were characterised by the presence of nitrites in the range from 1 to 5 mg kg^-1, and the least samples from 11 to 14 mg kg^-1. The contents of nitrates were significantly higher, ranging from 10.2 to 73.5 mg kg^-1 in the semitendinosus muscle and from 10.4 to 74.3 mg kg^-1 in the thoracis longissimus muscle. Such and higher level of contamination may be the cause of meat discolouration after heat treatment despite the absence of curing ingredients. It is necessary to continuously monitor the concentration of nitrates in raw materials, water and feed to ensure the complete safety of food of animal origin.

The article presents the results of homogeneity assessments for selected food mixes based on computer image analysis. The study was conducted on müsli and condiment mixes standardly available on the consumer market. A total of 40 different ready-for-use products were analysed. Collected samples from three package of each product were placed in a special chamber and then photographed. Photographs were then subjected to computer image analysis to acquire information on the percentage content of individual components. Homogeneity assessment was based on the contents of a selected component called tracer and the coefficient of variation (CV). Lower CV values (3.02-27.31%) and thus better homogeneity was observed for condiment mixes as compared to müsli mixes (3.57-59.15%). Fourteen of twenty condiment mixes had adequate (acceptable at CV ≤ 10%) mixing degree. For the müsli, only six of the tested mixes had appropriate homogeneity. The presented results are a preliminary to developing an image-based methodology for determining the uniformity of granular dry food mixes.

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.

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.

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.

The disulfide bonds and sulfhydryl in gluten were evaluated to investigate the effects of structural characteristics on the quality of white noodles. The free sulfhydryl concentration increased significantly, but disulphide bonds decreased initially, and then became stable with increasing sodium sulfite concentration. With a decrease in disulfide bond concentration from 56.78 μmol/g to 20.01 μmol/g in gluten added to noodles, microstructural graphs verified that the cross-section and surface of noodles became rougher and looser with more holes generated; optimal cooking time decreased from 4.4 min to 3.3 min for fresh noodles and from 10.11 min to 9.19 min for dried samples; water absorption and cooking loss increased from 159% to 203% and from 5.26% to 9.06%, respectively. A decreasing trend and marked differences were observed for hardness, springiness, chewiness as well as resilience of fresh and cooked noodles, but the cohesiveness of fresh noodles exhibited no significant changes (P < 0.05).

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.

Contents of eight biogenic amines (putrescine, cadaverine, spermidine, spermine, histamine, tyramine, tryptamine and phenylethylamine) were determined in vacuum-packed fillets of rainbow trout (Oncorhynchus mykiss). Fish flesh was treated using a solution of chitosan (2%, w/v) or monoacylglycerols (monocaprylin C8, monocaprin C10, 5%, w/v). The control and treated packs were stored at 3.5 °C for up to 25 days. Samples of good quality did not contain more than 30 mg kg-1 of either putrescine or cadaverine. Exceeding this limit was usually followed by a worsening of the sensory properties of samples. Chitosan was found to be the most potent additive, prolonging the storage time of fillets by approximately four times, compared to control samples. Histamine was not found in any sample treated with chitosan. of the monoacylglycerols, C8 was more efficient compared to C10. All additives are easily applicable to the surface of fish flesh.

Seeds of Czech poppies used for culinary purposes are frequently mixed with seeds of imported low-quality poppies with higher alkaloid content and poor taste properties. That not only decreases the quality of the product on the market, but it can also represent a potential health hazard for consumers. To prevent such adulteration, the method is needed that could clearly detect the presence of the low-quality poppies in the products on the market and which can also confirm the authenticity of the genetic material for growers. For that reason, length polymorphism of Simple Sequence Repeats was evaluated in the blue and non-blue poppy varieties of Czech and foreign origin. Used markers clearly distinguished 'Czech blue poppy' cultivars from blue poppies of another origin as well as from poppies of non-blue seed colour. We conclude that used markers can be applied to a commodity verification on the market to detect/exclude the presence of other genotypes.

The study aimed to demonstrate how irradiation affects the chemical composition and amino acids of Spunta potato flour, and the sensory evaluation of biscuit samples partially composed of irradiated potato flour. The potato flour was irradiated with 50 and 150 Gy. Protein, fat, total dietary fibre, ash, carbohydrates, ascorbic acid, and amino acids were analysed. Sensory evaluation of biscuits was conducted after adding potato flour as a partial replacement for wheat flour at ratios of 5, 10, and 15%. The results showed that potato flour contained ascorbic acid, which was absent in wheat flour. Potato flour had less total protein and carbohydrate and more ash and fibres than wheat flour. Total essential amino acids appeared at the highest percentage, particularly lysine at 8.29 ± 0.02, compared with non-essential amino acids in the samples irradiated at a dose of 150 Gy. The biscuits were prepared with different ratios of the irradiated potato flour at dose 150 Gy to white flour. Sensory evaluation for biscuits with 10% of potato flour scored 8.61 ± 0.01, 8.33 ± 0.02, 8.77 ± 0.02, and 8.38 ± 0.00 for overall acceptance, colour, texture and appearance, respectively. This study recommends using 10% of irradiated potato flour at 150 Gy blended with wheat flour to produce biscuits.

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.

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.

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, ΔB_pp ≈ 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.

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.

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.

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.

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.