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Cereals are generally known to have a positive influence on the general state of the human organism. The attention of the nutritional experts is paid especially to oats and barley. Besides their accessibility, these cereals are interesting due to their relatively high contents of soluble non-starch polysaccharides (fibrous material), out of which β-glucans have a dominant position from the aspect of health benefit. This paper presents a brief review of the latest knowledge on the positive effects of β-glucans on the consumer's health. The structure, occurrence, sources, and positive physiological effects of β-glucans on the cardiovascular system but also their antibacterial, antitumoral, immunomodulant, and radioprotective properties are mentioned. In the paper are given examples of β-glucans exploitation as functional ingredients in food, cosmetic, and pharmaceutical industries and as food additives on the basis of cereal fibres and cereal β-glucans.

Some yeasts are involved in flavour development of dry-cured meat products showing a positive impact on the generation of volatile compounds. The aim of this work was to design a method of routine analysis to evaluate the production of volatile compounds by yeasts to be selected as starter cultures. For this purpose, several variations of a minimum culture medium that included free amino acids, oleic acid, and α-ketoglutarate, incubated under similar conditions of water activity and pH as dry-cured meat products, were assayed. In these conditions, the representative yeast strains isolated from a dry-cured meat product were tested. The volatile compounds were analysed using Solid Phase Micro-Extraction and gas chromatography/mass spectrometry. In the designed media, the tested yeasts produced volatile compounds involved in flavour development of dry-cured meat products. In addition, all the strains showed the highest production of these volatile compounds in the complete minimum culture medium witch included α-ketoglutarate and oleic acid.

The total phenolic content (Folin-Ciocalteu method), free radical scavenging ability expressed as DPPH value, ferric reducing antioxidant capacity (FRAP), and oxygen radical absorbance capacity (ORAC) were determined in water extracts of leaves from Rosaceae family plants (Fragaria vesca L., Rubus fructicosus L., and Rubus idaeus L.). The antioxidant capacities of the extracts (in the order of the above mentioned methods) were 73.6-88.9%, 60.1-71.4%, 49.7-78.0% respectively, and 45.3-66.5% of that of green tea water extract. Further, the presence of 15 compounds (gallic acid, rutin, ellagic acid, caffeic acid, p-coumaric acid, quercetin, kaempferol, myricetin, quercetin-3-d-glucoside, ascorbic acid, (+)-catechin, (-)-epicatechin, epicatechingallate, epigallocatechin, procyanidin B1) was studied by HPLC-ECD and their antioxidant capacities were compared to the antioxidant capacity of the extracts. Out of the compounds studied, mostly (+)-catechin, ellagic acid, and (-)-epicatechin participated in the antioxidant capacities of the studied plant leaves water extracts. The antioxidant capacity of leaves infusions (determined by DPPH method) was lower than those of red wines and tea infusions, but comparable to the antioxidant capacities of white wines and fruit beverages.

The compositions and concentrations of lipid classes, fatty acids, tocopherols were determined in the lipids from blue-green microalga Spirulina platensis. Total lipids (TL) recovered using chloroform: methanol (2:1, v/v) were found to be 163.5 g/kg (on dry weight basis). The level of neutral lipids was the highest, followed by glycolipids and phospholipids, respectively. Among TL and lipid classes, palmitic, γ-linolenic and linoleic acids were the dominating fatty acids. Compared to the neutral lipids, the polar fractions were generally characterised by higher percentages of saturated fatty acids. The recovered lipids were characterised by high percentage of tocopherols, wherein γ-tocopherol constitutes about 73% of total tocopherols present, the rest being γ-tocopherol. Spirulina platensis lipids exhibited a strong radical scavenging activity towards stable DPPH free radicals, whereas 27% of DPPH radicals were quenched after 2 h incubation. TL and lipid classes inhibited the growth of different microorganisms except gram-negative bacteria. At high concentrations, the tested lipids appeared more effective against A. niger (28.3 ± 1.53 mm). The information obtained in the present investigation is useful for lipid characterisation and further chemical and nutritional investigations of Spirulina platensis.

The formation of low molecular carboxylic and hydroxycarboxylic acids as well as sugar and deoxysugar acids from monosaccharides (D-glucose, D-fructose, D-arabinose, DL-glyceraldehyde, and 1,3-dihydroxyacetone) was studied in three different model systems: aqueous and alkaline solutions of potassium peroxodisulfate (K₂S₂O₈), and sodium hydroxide solution. In total, 3 low molecular carboxylic acids (formic, acetic and propionic), 24 hydroxycarboxylic acids, and 12 corresponding lactones were identified and quantified by GC/MS. Formic, acetic, and propionic acids were isolated by extraction with diethyl ether and directly analysed by GC/MS; hydroxycarboxylic acids and their lactones were monitored as their trimethylsilylated derivatives using the same method. Formic, acetic, L-lactic, glycollic, DL-2,4-dihydroxybutanoic acids and aldonic acids derived from the parent sugars were the most abundant compounds in all model systems. Within the models investigated, the yield of carboxylic acids and hydroxycarboxylic acids (together with their lactones) ranged between 9.3-22.2% (n/n) and between 3.6-116.9% (n/n), respectively. The amount of acids was significantly lower in aqueous solutions of K₂S₂O₈ than in the alkaline solutions. The data obtained indicate that lower carboxylic acids are formed by both subsequent reactions (oxidation and/or intramolecular Cannizzaro reaction) of the sugar fragmentation products and direct decomposition of some intermediates such as uloses or hydroperoxides derived from the parent sugars. The acids possessing the original sugar skeleton are formed as a result of sugar oxidation or benzilic acid type rearrangement of deoxyuloses. Lower acids may also be formed by a recombination of free radicals.

The Lactobacillus species by 16S Amplified Ribosomal DNA Restriction Analysis (16S-ARDRA) was identified. Lactobacilli are bacteria often found in foodstuffs of both animal and vegetable origins. On one hand, they play an important role in the food spoilage and, on the other hand, they are used as starter cultures in food fermentation processes. The species-specific identification by traditional biochemical methods is time consuming and not always fully effective. Therefore, more efficient techniques are searched for. We focused on rapid identification of Lactobacillus isolates from different habitats. Forty-nine collection strains and isolates belonging to the genus Lactobacillus were discriminated. ARDRA was carried out with two restriction endonucleases. For the comparison of similarity, the Jaccard coefficient and clustering by the unweighted pair group method with arithmetic averages (UPGMA) were used. The percentages of similarity between profiles varied from 22% to 100% (AluI) and from 27% to 100% (MspI). This method proved applicable to the differentiation of 10 species.

Twenty formulas of eggplant dip, motabbal al-bathinjan in Arabic (MB), using different percentages of grilled eggplant, tahina (sesame pulp), and yogurt with constant levels of salt and citric acid were prepared and evaluated for the overall acceptability. The formula composed of 84.2% pulp of peeled grilled eggplant and 14% tahina without the addition of yogurt was found the most acceptable. The cold point of the canned MB was found to be in the geometric centre of the can. Canning of MB was conducted using three time/temperature combinations at the centre (80°C/5 min, 85°C/4 min, and 90°C/3 min). It was found that all heat-processes applied resulted in a commercially sterile canned MB with a high sensorial quality, as evidenced by the results of microbiological examinations, incubation tests, and sensory evaluation. Based on Bacillus coagulans, that may grow and cause flat sour spoilage of canned MB, the sterilisation value (F₁₀₀) was estimated of the whole heat-process from the filling till cooling to about 70°C.

The roles of some cake ingredients - oil, a leavening agent, and inulin - in the structure and physicochemical properties of batter and cakes were studied in four different formulations. Oil played an important role in the batter stability, due to its contribution to increasing batter viscosity and occluding air during mixing. The addition of the leavening agent was crucial to the final height and sponginess of the cakes. When inulin was used as a fat replacer, the absence of oil caused a decrease in the stability of the batter, where larger air bubbles were occluded. Inulin dispersed uniformly in the batter could create a competition for water with the flour components: gluten was not properly hydrated and some starch granules were not fully incorporated into the matrix. Thus, the development of a continuous network was disrupted and the cake was shorter and softer; it contained interconnected air cells in the crumb, and was easily crumbled. The structure studies were decisive to understand the physicochemical properties.

Lipolysis is of great importance in the development of the aroma and flavour of cheese and one of the usual ways of measuring it is to assess variations in fatty acids. The relative proportions of fatty acids in milk fat depend on the animal species, the stage of lactation and feed regime, the ripening time and the climatic conditions and microbiological quality of the milk. GC-MS is the reference method for the determination of fatty acids in cheeses, but the technique involves long analysis times.

The hygienic indicators and chemical composition of Prgica cheese produced from raw and pasteurised milks as well as the microbiological quality of dry red pepper used in the cheese production were investigated.. Prgica cheeses and originally packed dry red peppers were collected from five family farms and five vacuum-packed Prgica cheese samples were purchased from the supermarkets. Significantly lower fat (P < 0.01), protein, and total solids contents (P < 0.0001) of artisanal Prgica cheese in comparison to Prgica cheese purchased from the supermarkets were detected. Two samples of cheese produced on family farms and three samples purchased from the supermarkets had high numbers of yeasts and moulds. The yeasts Mucor sp. and Candida famata, and moulds Aspergillus niger and Aspergillus ochraceus, were detected in dry red pepper. The results showed that there was potential yeast and mould contamination among the Prgica cheeses produced from raw milk, as well as Prgica cheeses purchased from the supermarkets, produced from pasteurised milk under controlled conditions, also contained high numbers of yeasts and moulds probably due to contamination by dry red pepper used in their production.

Coenzyme Q₁₀ is an important mitochondrial redox component and endogenously produced lipid-soluble antioxidant of the human organism. It plays a crucial role in the generation of cellular energy, enhances the immune system, and acts as a free radical scavenger. Ageing, poor eating habits, stress, and infection - they all affect the organism's ability to provide adequate amounts of CoQ₁₀. After the age of about 35, the organism begins to lose the ability to synthesise CoQ₁₀ from food and its deficiency develops. Many researches suggest that using CoQ₁₀ supplements alone or in combination with other nutritional supplements may help maintain health of elderly people or treat some of the health problems or diseases. Due to these functions, CoQ₁₀ finds its application in different commercial branches such as food, cosmetic, or pharmaceutical industries. This review article gives a survey of the history, chemical and physical properties, biochemistry and antioxidant activity of CoQ₁₀ in the human organism. It discusses levels of CoQ₁₀ in the organisms of healthy people, stressed people, and patients with various diseases. This paper shows the distribution and contents of two ubiquinones in foods, especially in several kinds of grapes, the benefits of CoQ₁₀ as nutritional and topical supplements and its therapeutic applications in various diseases.

Chlorpropham is employed worldwide as an anti-sprout chemical to the harvested potato tubers during storage. A simple and precise analytical technique is developed for routine estimation of the sprout suppressant from a large number of potato samples supplied from commercial stores demanding quick analysis. Chlorpropham is extracted completely from potato tubers by intelligent reflux extraction followed by quantification using GC-FID (Gas Chromatography-Flame Ionization Detector) equipment. In this article, the performance of the technique is compared with the lengthy extraction/cleanup process, and the results are validated as per one-way analysis of variance. The recommended technique is found to offer rapid, accurate, and reliable analytical results with ease in handling a large number of samples constituting a wide range of residual chlorpropham levels often found in a complex structural commercial potato stores.

The whole buckwheat flour (WBF) was used in Turkish flat bread, lavaş, up to 30% level without gluten, and up to 40% level with gluten and sodium stearoyl-2-lactylate (SSL) additions. Some physical, chemical, and sensory properties of lavaş bread samples were determined. While ash, crude fiber, phytic acid (PA), Fe, K, Mg, and P contents of lavaş breads increased with WBF addition, gluten supplementation caused an increase especially in protein and Ca contents. Leavening process decreased PA contents in the breads compared to raw material, but WBF substitution increased PA contents up to 729 mg/100 g. As a result, the utilisation of WBF in lavaş bread improved the nutrients contents of the bread except PA. The dark colour and slight bitter taste of the WBF affected the sensory score of lavaş bread negatively at 40% substitution level, but the overall acceptability values did not change significantly (P < 0.05) compared to control sample.

Combined culture of lactic acid bacteria (Lactobacillus brevis, L. plantarum i L. sanfranciscencis) and baker's yeasts was used in order to reduce immunoreactivity of gluten from wheat. Flour and dough samples were analysed in terms of lactic acid fermentation and thermal processing. Their immunoreactivity was determined with ELISA method using both anti-gliadin antibodies from patients suffering from coeliac disease and rabbit anti-QQQPP peptide (main epitope of flour allergen) antibodies. Also, immunoreactivity was measured in the final products after simulated digestion. The obtained total effectiveness of the fermentation and digestion processes amounted to less than 30% relative to immunoreactivity of human anti-gliadin antibodies and less than 10% relative to immunoreactivity of anti-QQQPP peptide antibodies as compared to the baking made with non-fermented flour.

The feasibility of metabolomic fingerprinting approach based on ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-QTOFMS) was studied to assess its ability to discriminate between maize varieties, and to show the associations between them on the metabolomic level. The non-targeted metabolomic analysis was applied to assess the variability within two varieties grown under different environmental conditions and to characterise the association within a sample set comprising both conventional and transgenic (MON-ØØ81Ø-6) maize varieties cultivated under the same environmental conditions (locality). Typical metabolomic fingerprints were established for individual plants. The plants representing two varieties formed well separated clusters. Metabolomic fingerprints of the second sample set enabled their unambiguous discrimination. The differences in metabolomic fingerprints between maize varieties were identified and documented by grouping in PCA and/or CA. The results indicate a similar genetic basis of transgenic maize varieties as they descend from a MON 810 event. The results explicitly showed that the variability of the metabolites in MON 810 did not exceed the ranges measured within the conventional varieties, thus supporting the concept of substantial equivalence.

The aim of the study was to describe the distribution of total mercury in the tissues of fish originating from important Czech fishing locations and to determine the level of methylmercury as a percentage of total mercury (Hg speciation). At six important fishing locations a total of 144 fishes of 13 species were caught and analysed. Samples of muscle, liver, gonads and scales were analysed for total mercury and in the case of muscles for methylmercury concentrations. Total mercury was determined by AAS using an AMA 254 analyser, and methylmercury determination was performed by GC/ECD using a GC-2010A chromatograph. Total mercury concentrations in muscle and other tissues of all the fish from all fishing locations were below 0.5 mg/kg, with the exception of 6 asps (Aspius aspius). A significant (P < 0.05) correlation was found between the total mercury concentrations in scales and other tissues. Methylmercury made up about 46-100% of total mercury in muscle. The overall results confirmed the good hygienic quality of fish from important Czech fishing locations.

In brewing, yeast may be reused many times. A number of yeast repitchings differs significantly among the breweries. Adjusting the number of times a strain may be serially repitched is of great importance for quality and consistency of final products. The fermentative and physiological characteristics of the yeast culture used in successive laboratory scale fermentations were determined. Yeast physiological state was assessed by the measurement of the levels of intracellular carbohydrates. In our investigation there were not any detectable changes in yeast capacity to ferment. No significant variation in the production of flavour compounds was found either. However, intracellular glycogen and trehalose contents were dependant on the yeast strain, generation number and wort gravity. Nevertheless, an alteration in the yeast physiological condition during serial repitchings occurred in a different mode than in previous studies confirming that the impact of serial repitchings is strain and medium dependent to a large extent.

Folin-Ciocalteu reagent (FCM) and Price and Butler method (PBM) were used for spectrophotometric determination of the total content of phenolic compounds in 29 wines (8 white, 21 red). The average contents of phenolic compounds determined by FCM and PBM were 108 (90-119) and 105 (90-129) for white wines, and 1545 (874-2262) and 547 (306-816) mg/l of gallic acid equivalents (GAE) for red wines, respectively. The reason for the lower PBM values in red wines is the higher reactivity in PBM of phenolic compounds, especially of gallic acid generally used as a standard in the above methods. The higher reactivity of the standard means that the measured absorbance of the sample responds to a lower concentration. The average total antioxidant activities determined by TEAC (Trolox Equivalent Antioxidant Capacity), FRAP (Ferric Reducing Antioxidant Power), and DPPH (using diphenyl-p-picrylhydrazyl radical) were 5.14 (4.30-6.14), 1.43 (0.86-2.14), and 0.71 (0.61-0.81) of Trolox equivalents (TE) and 26.44 (13. 9-34.4), 9.43 (4.92-13.9), and 5.52 (2.91-8.62) mmol/l TE for white and red wines, respectively. Almost the same molar absorptivities with TEAC and DPPH methods were found while with FRAP method it was somewhat higher (about 1.56-times). The ratio of the values determined by FRAP and DPPH methods for white and red wines were 2.0 and 1.7, respectively. The TEAC values were 2.8- and 4.8-fold higher than those determined by FRAP and DPPH methods, respectively. The radical ABTS*+ used in TEAC method is therefore the most reactive and responds to the highest number of hydroxyl groups of the phenolic compounds of wines.

A method to obtain an oligopeptide with high Fischer ratio is described. Corn gluten meal (CGM) was hydrolysed with Alcalase 2.4L using a two-step hydrolysis. In the first-step hydrolysis, the enzyme reaction conditions for hydrolysing CGM were optimised by using the orthogonal experimental design, while pH = 8.0, temperature = 55°C, enzyme to substrate ratio (3:97, w/w), and the substrate concentration = 5% were identified as the optimum conditions, under which up to 11.62% degree of hydrolysis (DH) could be obtained. The hydrolysate was then fractionated by ultrafiltration using a membrane with the molecular cutoff of over 10 kD at 20 kPa. For the second-step hydrolysis, the filtrate was adjusted to pH 6.0, then papain was added at 50°C and the mixture was maintained for 3 hours. The hydrolysate was obtained after inactivating papain and centrifuging. Then the salt (mainly NaCl) in the hydrolysate was removed with an ion exchange resin at the speed of 8 times bed volume per hour, and aromatic amino acids were removed through absorption by active carbon. By using Sephadex G-25 gel filtration chromatography, a peptide mixture with low molecular weights between 1000 and 1300 was obtained. Finally, tests on amino acid composition and free amino acid concentration of oligopeptide solution showed that the oligopeptide had a high Fischer ratio of 34.71 and the yield of 11.59%.

The objective of this work was to verify the effect of the lean meat proportion on the chemical composition of the meaty parts (loin and ham) of pork. A total of 116 finishing hybrid pigs commonly used in the Czech Republic were fattened for this purpose. The pigs were divided according to the lean meat proportion criterion into 3 groups, i.e. more than 60.0%, 55.0-59.9% and 50.0-54.9%. Representative muscle samples were taken from the right halves of these pigs. They were then homogenised and submitted to chemical analysis. The results of the measuring showed that the values of the water content, intramuscular fat (IMF), crude proteins, and ash matter ranged in the loin between 72.50-72.80%, 1.56-1.96%, 23.20-23.40%, and 1.37-1.40%, respectively, and in the ham between of 70.43-71.59%, 3.52-4.26%, 21.67-21.95%, and 1.42-1.56%, respectively. The ascertained values of the water content and crude proteins with regard to the increasing lean meat proportion in the carcasses did not show any developmental tendencies. As for the content of IMF, it was determined that the higher was the lean meat proportion, the lower was the IMF content. Concerned of sensoric quality traits it means that pork meat from supermeaty hybrid pigs shows lower quality. Concerning the content of ash matter, it was observed that the ash content increased with an increasing lean meat proportion. In the carcass part of the musculus longissimus lumborum et thoracis (MLLT), it was demonstrated that the higher was the lean meat proportion, the lower was the content of amino acids - threonine, isoleucine, lysine, aspartic acid, serine, and proline. From point of the production of exceedingly meaty pigs (over 60%), it can be expected a worse nutritional pork meat value. In the carcass portion of the musculus semimembranosus (MS), the contents of valine, isoleucine, phenylalanine, lysine, serine, proline, and glycine increased with an increasing lean meat proportion. Within the framework of statistical evaluation of differences between the groups, the values of IMF ((P ≤ 0.01) in MLLT, water content, IMF, ash matter, threonine, valine, phenylalanine, lysine, aspartic acid, serine, glycine, and alanine in MS were highly significant ((P ≤ 0.05; (P ≤ 0.01 and (P ≤ 0.001).

Fusarium head blight (FHB) is a serious cereal disease in the CzechRepublic. The most important pathogen associated with FBH is Fusarium graminearum, which can produce trichothecenes, mainly deoxynivalenol (DON) and its derivates. A set of 103 F. graminearum isolates were isolated from naturally infected wheat ears collected from 20 localities (25 ears from one locality) within the Czech Republic, in the year 2004. The ears were evaluated for DON content by ELISA. Maximum detected value was 30.7 mg/kg. A group of PCR assays targeting the segments of the Tri7, Tri13 and Tri3 genes were used to determine the chemotypes of F. graminearum isolates. All the isolates belonged to DON producing chemotype. Further discrimination revealed that almost all (99.03%) isolates belonged to 15-ADON chemotype, and only one (0.97%) isolate belonged to 3-ADON chemotype. The genetic variability of the isolates was assessed from their AFLP fingerprints. The populations were highly heterogeneous both within and between locations, and no clear evidence for the association between AFLP profile and geographic origin was found out.

Calculations of transient temperatures of food products after they are transferred from a warm environment into a display cabinet, require data on the surface heat transfer coefficient (SHTC). There is no forced air flow in an ordinary display cabinet, so the energy transfer is achieved mainly by free convection, conduction to a supporting plate, and radiation. Theoretical analysis of the heat transfer to a cylindrical sample demonstrates the relative influences of these mechanisms. This work investigates the apparent surface transfer coefficients with metal models. Heated models were placed individually (bare) in containers with and without lids. Each model was surrounded by identical containers filled with water. These were initially at the same temperature as the model or at the mean cabinet temperature. There were one, two, or three layers of these water containers. From the measured time-temperature histories of the model and the air surrounding the model, the SHTCs were calculated as functions of time and transformed into the dependencies between SHTC and temperature difference. The highest SHTCs were observed when the model was placed directly on the metal shelf of the display cabinet. The models surrounded by cool water containers showed lower SHTC values. The lowest SHTC values were found with the models placed in the middle of three layers of warm water containers. Placing the model on an insulating base leads to a lower SHTC. This effect confirms that the heat conduction through the substrate increases the heat transfer from the model and thus increases the average value of the apparent SHTC.

Caciottina massaggiata di Amaseno, a typical dairy product of the Lazio Region prepared from buffalo milk, was analysed for moisture, fat, protein, pH, and acidity content at different storage (0, 3, 6, and 9 months after production). Cheeses were also evaluated for various sensory attributes (taste, flavour, texture, and overall acceptability) during storage. We evaluated the flavour profile and acceptability of Caciottina cheeses of varying maturity using a descriptive analysis. Descriptive sensory profiles of selected cheeses were determined using a trained panel (n = 12) and an established cheese flavour sensory language. In quantitative descriptive analysis a trained panel rated the cheeses for colour, odour, taste and texture. In the affective tests the panellists evaluated the samples for overall quality. The results proved that months of production had significant effects on the sensory quality of the cheeses.

β-Galactosidase is an important industrial enzyme in the hydrolysis of milk and whey lactose. The enzymatic hydrolysis of lactose allows to avoid health and environmental problems posed by this disaccharide. In addition, this enzyme catalyses the formation of galacto-oligosaccharides, which are prebiotic additives for the so-called "healthy foods". β-Galactosidase is one of the relatively few enzymes that have been used in large-scale processes in both free and immobilised forms. This article presents a review of recent trends in immobilisation of β-galactosidase and their application in food industry.

Biogenic amines (histamine, tyramine, tryptamine, phenylethylamine, cadaverine) including biologically active polyamines (putrescine, spermidine and spermine) were determined by HPLC method after 7, 21, 35, and 49 days of ripening in the core (C) and edge (E) samples of a blue-veined cheese, popular in the Czech Republic under the trade mark Niva, produced in the three consecutive months (October, November, December) from pasteurised cow milk using Penicillium roqueforti spores; two vats were produced in each month. The cheese vat, including the production period, accounted for (P < 0.05) one third and two thirds of the explained variability of the sum of biogenic amines and the sum of polyamines, respectively. The ripening time was significant (P < 0.05) from this viewpoint only in the case of the sum of biogenic amines (nearly half of the explained variability). Putrescine and spermidine contents in cheese did not change (P > 0.05), spermine content even decreased (P < 0.05) with increasing time of ripening. Tyramine content (Y, mg/kg) in the core samples increased linearly with increasing time of ripening (X, days), Y = 6.3 + 11.69X, R² = 0.26, P < 0.001, contrary to the edge part where tyramine content did not change (P > 0.05). At the end of ripening (49 days), tyramine was quantitatively the most abundant amine (the mean and median 380 mg/kg and 289 mg/kg, respectively), its content in different cheeses (vats) varying from 10 mg/kg to 875 mg/kg. Cadaverine concentration varied between 3 mg/kg and 491 mg/kg (the mean 114, median 56 mg/kg). The levels of other biogenic amines and polyamines (with the exception of putrescine in the edge part of one of the December vats: 117 mg/kg) were very low even at the end of ripening. Tyramine contents at the end of ripening in the core-samples were higher (P < 0.01) in comparison with those in the edge-samples, contrary to histamine, cadaverine, putrescine, and spermine contents.

The presence of genetic modifications was analysed in a total of 100 samples of non-labelled vegetarian and healthy food products. The basic raw materials in the samples tested comprised maize, soya, and/or rice. The screening of all samples was performed using the primers for CaMV35S promoter. The positive samples from this initial screening were further subjected to the analysis of specific transgenic material to determine the type of GMO present with subsequent quantification. Roundup Ready soya was found in eight samples, but its content was below the limit of 0.9%. None of the analysed samples of food products contained GM maize and GM rice. Considering that the investigated samples were imported mainly from EU countries, it can be concluded that the control of GMOs is carried out systematically and in accordance with the Serbian GMO Law.

Barley primarily serves as a major animal feed crop; smaller amounts of barley are used in health foods and in the malting process. Detailed geometric parameters of kernels are very important for the design of food engineering processes, such as the air transport, drying, milling, and malting. Image analysis was used to determine the size parameters of one hundred kernels of selected varieties of Hordeum vulgare L. The data for every kernel captured were stored for further use, together with the mean, standard deviation (SD), coefficient of variation (CV), and images themselves. The measured data were then used to compute the volume and surface area of each of the five kernel models (Models 0-4), the results being subsequently verified by pycnometric measurement. Model 0 represents the general ellipsoid, models 1-3 various combinations of two parts of a general ellipsoid with one or two cone frustums. The best fitted model 4 was a combination of two cone frustums. Based on the results of image analysis measurements and on the presented model 4, a simplified method for the specific surface estimation of barley grains from the weight of 1000 kernels is recommended.

The ability of phenolic acids (gallic, gentisic, protocatechuic, syringic, vanillic, ferulic, caffeic, and sinapic; 600 mg/kg) to protect α-tocopherol was tested during the heating of sunflower oil on a hot plate set at 180°C and was compared with the ability of these phenolic acids to slow down the formation of polymerised triacylglycerols (TAG) in the same conditions. The half-life of α-tocopherol (calculated as the time needed for the α-tocopherol content to decrease to 50% of the original value) was extended significantly by gentisic, caffeic, and gallic acids (from 1.16 h to 1.77 h, 1.78 h, and 2.26 h, respectively), while the formation of polymerised TAG was slightly suppressed only by gallic acid.

The antioxidant capacity of some herbs used in dietology practice was determined by the DPPH free radical method, which was calibrated with ascorbic acid. Partially hydrophilic phenolic compounds are the most active compounds in plants, and therefore water was used as the extraction agent. Besides antioxidant capacity, the content of total phenolic compounds was also measured and a strong correlation between these two variables was found. The extracts of lemon balm (Melissa officinalis L.), peppermint (Mentha x piperita L.), oregano (Origanum vulgare L.), Greek oregano (Origanum heracleoticum L.), sage (Salvia officinalis L.) and winter savory (Satureja montana L.) showed very significant activity. It was comparable with the activity of green tea in the case of oregano and peppermint. Lower activity was observed in the case of rosemary (Rosmarinus officinalis L.), marjoram (Majorana hortensis), hyssop (Hyssopus officinalis L.), sweet basil (Ocimum basilicum), and lovage (Levisticum officinale Koch.). The inhibitory activity of the herb extracts was monitored also during the autooxidation of lard. Very high antioxidant capacity was observed mainly in sage samples, but also in marjoram and Greek oregano. The extracts of peppermint, oregano, rosemary, winter savory, lemon balm and hyssop showed middle activity comparable to that of α-tocopherol. The antioxidant capacity of sweet basil and lovage was insignificant.

In this study, the effects were evaluated of butylated hydroxyanisole (BHA), ascorbic acid (AA) and α-tocopherol (TO) on the stability of raw mechanically deboned chicken patties stored at -20°C for 6 months. pH, thiobarbituric acid reactive substance (TBARS), haem iron (mg/kg), metmyoglobin formation (%) and colour (L*, a*, b*, C* and h values) of patties were measured for 0, 2, 4, and 6 months of storage time. pH values were found to be the highest in the initial storage period. TBARS values were observed to range between 0.33 and 2.40 mg malondialdehyde/kg of sample and the L*, a*, and b* values of the patty samples during the storage period were found to range between 38.14 and 49.52, 9.01 and 20.87, and 7.28 and 14.62, respectively. The haem iron and metmyoglobin contents were found to range between 8.39 and 10.87 mg/kg and 19.26% and 45.91%, respectively. As a result, it is suggested that L-ascorbic acid and α-tocopherol can be added into chicken patty samples in view of the storage quality parameters mentioned above.