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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 human nutrition fats are physiologically important food constituents but also the components most liable to oxidative degradation. The oils included in the study were refined (sunflower, extra-sunflower, soybean, and rapeseed) as well as unrefined (olive and pumpkin-seed) oils. The aim of our study was to determine the fatty acid composition, tocopherol content, and quality parameters such as the free fatty acid content, peroxide value, and induction time. Extra virgin olive oil had the highest average peroxide value, while unrefined pumpkin seed oil had the lowest one. The acid value of the unrefined oils was higher on average than that of the refined oils. Soybean oil had the highest total tocopherol content and extra virgin olive oil the lowest one. The refined oils with higher contents of saturated and monounsaturated fatty acids and lower polyunsaturated fatty acid contents had a high oxidative stability. A negative correlation has been found in the oils between the induction time and polyunsaturated fatty acid content. Among the oils investigated, unrefined pumpkin seed oil was the most oxidatively stable, the other oils following in the decreasing order: extra virgin olive > high oleic sunflower > rapeseed > soybean > sunflower oil. The oxidative stability of the unrefined oils was better than that of the refined oils.

Manufacturing of novel foodstuffs supplemented with live probiotic bacteria has recently been intensively investigated. The supplementation of confectionery with probiotics is troublesome since some unit technological processes are conducted at high temperatures and the products are usually stored at ambient temperature. Our group has developed a method of the production of milk chocolate, sweetened with either sucrose or isomalt and aspartame, containing 32, 36, or 40 g/100 g fat, and supplemented with live cells of probiotic bacterial strains: Lactobacillus casei and paracasei. This new milk chocolate displayed the same sensory properties as the reference, probiotic-free chocolate. The number of live bacterial cells was maintained at the functional level of 10⁶ / 10⁸ cfu/g after keeping for 12 months irrespective of the temperature. The highest number of live probiotic bacteria survived in the chocolate kept at 4°C. Thus the product can be regarded as functional food.

Farmers in rural areas of almost all the districts of Bangladesh cultivate different varieties of edible plant karela to satisfy nutritional requirements. Herein, we report on the characteristics of seed oils and nutrients and mineral contents of seeds from three varieties of karela. Most of the physicochemical characteristics were significantly (P < 0.05) affected with the samples tested. Seed oils of all varieties displayed a higher degree of unsaturation and in GLC reported herein, only five fatty acids were identified. The profiles of fatty acid composition were not wholly similar in all varieties in which unsaturated fatty acids represented more than 72%, α-eleostearic acid having been detected in the amount of 50.36-53.22%. Acylglycerol classes were estimated to be monoacylglycerols (1.18-2.01%), diacylglycerols (1.83-2.98%), and triacylglycerols (91.11-93.03%) whereas lipid classes included neutral lipids (86.83-91.09%), glycolipids (4.37-7.43%), and phospholipids (3.22-4.62%). Of the major energy producing nutrients, all varieties contained large amounts of lipid (33.93-36.21%) and protein (18.23-21.36%), and potentially useful amounts of calcium (383.45-440.96 μg/g), iron (41.10-45.03 μg/g), and other essential minerals. The nutrient information presented in this report should stimulate the local public health authorities in Bangladesh to consider the question of recommending the vegetable karela to be consumed by adults and children alike in Bangladesh, including pregnant women and others with higher than normal nutritional requirements.

A high seed vigour is a desired trait in agronomy as it promotes the fast field emergence and homogeneity of harvest, which is necessary for producing quality food raw material. In this work, we studied the effects of the seed vigour on the bread quality. Relationships between the grain vigour, nutrients and anti-nutrients, contents, and bread volume were evaluated using the samples acquired from official variety trials. In the trials, the grain vigour was perceived as the grain ability to germinate in stress conditions, i.e. at 10°C in a solution of polyethylene glycol (PEG 6000 at osmotic pressure - 2 bars, the so called permanent wilting point). The results showed that the locations and years changed the bread volume but not the rank of the varieties tested in the trait. A higher grain vigour was significantly related to a higher falling number during two of the three trial years. The vigour was negatively related to the lipase activity. Moreover, other decomposing enzymes showed a similar tendency as was that found in the samples with the most diverse vigour. The grain samples with 80-90% vigour produced the greatest bread volume. The grain with a vigour below or above this range produced less voluminous loaves. The varieties of the highest quality produced the most voluminous bread from the samples reaching the grain vigour of 90-95%. The standard germination test was not related to the vigour and was less responsible for the bread quality. High-quality varieties had higher contents of total polyphenols than the varieties of lower quality, and the polyphenol content was correlated with the vigour (r

As far as honey is concerned, microwave oven heating finds its use especially for crystallised honey reliquefying. We focused on monitoring the changes in hydroxymethylfurfural content which is an indicator of heat damage done to honey, among others. Microwave honey heating was carried out in four degrees of microwave power levels over seven variously long time periods. In total, 22 analysed honey samples came directly from bee-keepers from the Czech Republic from the 2004 and 2006 harvests. Hydroxymethylfurfural content was determined by HPLC method using a liquid chromatograph Alliance 2695 with a PDA detector 2996. We obtained relatively interesting results: despite the honey having reached relatively high temperature levels (80-90°C) at the highest power levels and the longest time periods, there was no gradual significant increase in hydroxymethylfurfural content which could be expected at conventional heating. On the other hand, hydroxymethylfurfural content varied in the course of heating of the individual samples, which is a very interesting result. A significant role was played also by the botanic origin of the honeys because the course of the changes in hydroxymethylfurfural content due to microwave heating was not the same in all honeys analysed.

Volatile aroma compounds production by two autochthonous Saccharomyces cerevisiae strains, isolated from Istria region, and three other yeast strains (Saccharomyces bayanus and two commercial Saccharomyces cerevisiae wine yeasts) was investigated on a small scale using synthetic VP4 medium and Graševina must at 12 and 20°C. The results obtained by gas chromatography analyses were compared with the aroma production properties of the native microflora, remaining after Graševina must sulphiting. In both media and at both temperatures, the wine yeasts investigated showed different metabolic profiles regarding the tested volatile aroma compounds, which should be taken in consideration for autochthonous wine production. Although the synthetic medium proved to be appropriate for the investigation of the fermentative properties, the determination of secondary aroma production by wine yeasts has to be conducted by must fermentation or possibly by fermentation of another synthetic medium whose composition would be more similar to must.

The occurrence and content of some polyphenols and the antioxidant activity of compounds present in grape berries, stems and leaves of Vitis vinifera L. were evaluated. Three white and three blue varieties of grapevine were investigated. The contents were determined of trans-resveratrol, trans-piceid, caftaric acid, tryptophan, catechin, epicatechin, total polyphenols, and flavanols, both in healthy material and in the samples of the plant material infested with microorganisms (Botryotinia fuckeliana Whetzel anamorph Botrytis cinerea Pers.; Uncinula necator (Schw.) Burr; Plasmopara viticola (Berk. & M.A. Curtis) Berl & De Toni). The antioxidant activity of the extracts obtained was determined by different methods: FRAP (Ferric Reducing Antioxidant Power), DPPH (2,2-diphenyl-1-picrylhydrazyl radical) and TAC-PCL (Total Antioxidant Capacity of Photochemiluminescence). The content of trans-resveratrol varied between 0.3-2.3 mg/kg and 0.7-12.1 mg/kg in non-infested and infested grape berries, respectively. The content of trans-piceid between 0.6-2.9 mg/kg and 1.5-6.3 mg/kg in non-infested and infested grape berries, respectively. The content of trans-resveratrol varied between 2.5-10.3 mg/kg and 3.7-20.9 mg/kg in healthy and in infected leaves, respectively. The content trans-piceid varied between 11.3-58.4 mg/kg and 18.5-60.9 mg/kg in the healthy and in the infected leaves, respectively. The highest content of trans-resveratrol was found in stems (16.3-276.3 mg/kg). In young lateral shoots, the highest levels of trans-piceid (12.6-99.7 mg/kg) and caftaric acid (474-2257 mg/kg) were determined. The infested grape berries showed a higher antioxidant activity, which was most closely correlated with the content of total polyphenols (correlation coefficient = 0.8336-0.9952).

The effects of inulin HPX and maltodextrins, and also the potentially probiotic Lactobacillus plantarum 14 strain, used separately and in combination in white cheese production, on the gastrointestinal microflora of Wistar rats was investigated. The prebiotic addition to the cheese was 2.5%, whereas probiotic and synbiotic cheeses contained at least 10⁷ CFU/g of live L. plantarum cells. The counts of Bifidobacterium sp., Lactobacillus, coliforms, and the most probable number of anaerobic proteolytic bacteria were evaluated. After a 10-day feeding experiment, significant changes (P < 0.05) were noted in the most probable number of anaerobic proteolytic bacteria spores, which was the highest in the group receiving a diet with the cheese containing the potentially probiotic strain and inulin HPX. A short-time ingestion of low doses of prebiotics or synbiotics did not alter the counts of Lactobacillus, Bifidobacterium, and coliforms in healthy rats.

HPLC method for 5-methyltetrahydrofolate (5-MTHF) determination in vegetables was optimised for the folate release from the food matrix. Enzymatic hydrolyses using the subsequent addition of α-amylase, protease, and conjugase from hog kidney, or their combinations, were tested. The highest release values were obtained with the application of enzymes α-amylase and conjugase, amounting to 112.4-127.0% of the values obtained in the processing with sole conjugase. The simultaneous addition of both enzymes and the incubation at pH 4.9 did not suppress the release of folates. Spinach, Chinese cabbage, lettuce, cauliflower, and broccoli contained more than 50 μg of 5-MTHF/100g, whereas less than 25 μg/100 g was found in potatoes, carrot, white cabbage, green and yellow pepper. Individual vegetables differed in the folate retention during their boiling under constant conditions. The highest retention was found in Brussels sprouts, cauliflower, and broccoli. After 8 min boiling more than 75% of the initial amount of 5-MTHF remained in these vegetables. Lower values of 5-MTHF retention, between 37% and 52% of their initial content, were found in spinach, savoy cabbage, and carrot.

The effect of carbon monoxide was studied on the colour stabilisation of minced meat and on oxidation of lipids. The meat colour was evaluated using reflectance spectrophotometry and video image analysis (software LUCIA 5.20). Minced meat (beef and mixture of beef and pork) was packed under industrial conditions into three different modified atmospheres (MA) consisting of combinations of oxygen, carbon dioxide, carbon monoxide, and nitrogen. Carbon monoxide prevented the oxidation of lipids and haem pigments in minced meat and thus stabilised the red colour of minced meat. The redness a* of the meat packed under CO was constant during storage (nearly a* = 20), whereas in MA containing oxygen this value decreased (a* = 5). The thiobarbituric acid reactant substances content rose in the samples packed under MA to 2 mg/kg, whereas in CO atmosphere it did not exceed 0.1 mg/kg.

FT-IR spectra were recorded of Escherichia coli cell mass with the aim of obtaining spectral traits possibly useful in a rapid detection and characterisation of this indicator bacterium. A well differentiated spectrum was obtained from the cell mass harvested in a stationary phase of growth, e.g., after 24 h, from a minimum nutrient broth. The cell mass, harvested either earlier or grown in nutrient solutions which contained an enhanced carbon or nitrogen concentrations delivered somewhat different IR spectra, apparently due to a higher content of nucleic acid components as related to other structural constituents of bacterial cells. Consequently, the FT-IR spectra of E. coli, although rather rapidly to collect, seem only capable of delivering useful and reproducible information if the cell mass is obtained under standardised cultural conditions.

The purpose of this study was to investigate the relationship between the carcass weight and the level of skatole in boar back fat samples with descriptive sensory profiles (trained sensory panel) immediately after heating the fat samples (warm). A weak correlation was found between the carcass weight and skatole level in fat (P > 0.05). Between skatole levels in the fat of boars, whose carcass weight was below 70 kg, and of those with the carcass weight equal or above 70 kg, there was a statistically significant difference (P < 0.05). The average content of skatole in the fat tissue of the boars < 70 kg, (0.18 ± 0.09 mg/kg fat, respectively) was below the commonly used respective thresholds for tainted meat (0.20 mg/kg fat), 53% of the samples showed the values of ≤ 20 mg/kg, and 73% of the samples the values of ≤ 25 mg/kg. In the group ≥ 70 kg (0.40 ± 0.39 mg/kg fat, respectively), 80% of the samples revealed the values of ≥ 20 mg/kg, and 66% of the samples the values of ≥ 25 mg/kg. Our results show that a positive, compelling and statistically highly significant correlation exists between the skatole level and the sensory assessment of skatole intensity in fat.

Enzymes with high specific activities at low temperatures have potential uses in the food industry. Cold-adapted microorganisms are potentially useful sources of cold-active enzyme. To find cold-adapted β-galactosidase, we isolated several cold-adapted microorganisms from glacier zone soil. One cold-adapted β-galactosidase producing strain was obtained. The biochemical characteristics and the results of 16S rDNA sequencing identified the strain as Rahnella aquatilis. The enzyme was purified by column chromatography after which a single protein band migrating near 60 kDa was observed by means of SDS-PAGE. The β-galactosidase was optimally active at 35°C and at pH 6.5 when assayed with o-nitrophenyl-β-D-galactopyrano-side as substrate. The enzyme activity was sensitive to temperatures above 40°C and was undetectable at 45°C. Metal ions Mn²⁺and K⁺ activated the enzyme while Cu²⁺, Zn²⁺, Fe³⁺, and Al³⁺ inhibited the activity. The enzyme was also assayed for lactose hydrolysis. When milk is treated with the enzyme at 30°C for 2 h, the degree of lactose hydrolysis can reach 80%. It has, thus, potential applications in the food industry.

The inhibition of mutagenicity was assessed by Ames test by bacterial strains Salmonella typhimurium TA98 and TA100 using two mutagens and methanolic extracts of healthy fresh berries of blue grapevine varieties - St. Laurent, Portugal, André and white varieties - Chardonnay, Welschriesling, Pinot Gris and berries infected with Botrytis cinerea fungus. As model mutagens, two compounds whose presence in food is real, 2-amino-3-methyl-3H-imidazo-(4.5-f-)-quinoline (IQ), arising from certain heat treatments of meat and acting as indirect mutagen after metabolic activation, and N-nitroso-N-methylurea (MNU) acting as a direct mutagen, were applied. An increased risk of MNU is due to its possible endogenous formation. Fermentation sediment after vinification of the varieties Chardonnay, Welschriesling and André was tested by similar experimental system. All extracts showed strong positive inhibition of mutagenicity, berries infested with Botrytis cinerea also in diluted extracts. Positive inhibition was demonstrated also by fermentation sludge.

This review article is a part of the survey of the generally accepted biosynthetic pathways that lead to the most important natural pigments in organisms closely related to foods and feeds. The biosynthetic pathways leading to xanthones, flavonoids, carotenoids, and some minor pigments are described including the enzymes involved and reaction schemes with detailed mechanisms.

The effects of the pressing technology and clarification of white grape musts on concentrations of phenolic compounds and their antioxidative capacity were investigated. Four different varieties were processed by hydraulic or pneumatic pressing technologies. In the individual stages of pressing and after the application of different doses of the clarification agent, must samples were analysed for the content of polyphenols and the antioxidative capacity. The highest concentrations of caftaric acid were estimated in the musts made by hydraulic pressing from grapes of Welschriesling variety. On the other hand, musts made from grapes of Grüner Veltliner showed the highest contents of trans-piceid in both variants of pressing. The values of antioxidative capacity of the must samples analysed were not significantly different. The influence of clarification on the changes of phenolic substances in young red wines of Saint Laurent variety was also studied. Six various clarifiers were tested as applied in two different doses. Polyvinylpolypyrrolidone caused the highest losses of trans-resveratrol in the course of red wine clarification. The concentrations of catechin, epicatechin, and total anthocyanins as well as the colour parameters of red wines were influenced at most by the application of egg white.

Rheological and textural characteristics were studied in a set of 11 samples of yoghurt-modified mayonnaise at 15, 20, and 25°C. The rheometer Rheostress 300 was used to determine the static yield value, apparent viscosity, thixotropy, and elasticity. The sensory texture and flavour profiles were developed and determined in agreement with the respective international standards, using a group of selected and trained assessors. The yield value and apparent viscosity substantially decreased with increasing temperature, but thixotropy and sensory characteristics were not significantly affected by temperature. Linear and semilogarithmic relations were observed between the analytical parameters, but more complex relations, showing a maximum or a minimum, were found in some cases. Thixotropy was related to most of the sensory parameters, viscosity was related to spreadability, and significant relationships existed between the texture acceptability and the flavour acceptability. Rheological measurements were thus useful for a rapid prediction of the sensory properties of yoghurt-modified mayonnaises, but could not be used to replace any textural analysis.

The sera from 690 slaughtered fattening pigs from 15 farrow-to-finish swine herds (12 herds of unknown Salmonella status, 3 herds known as latently infected) in the Czech Republic were examined for Salmonella antibodies in a cross sectional study using an ELISA test. Salmonella seroprevalence ranging from 0% to 20% was found in 14 herds. Seroprevalence of 73.9 was found in 1 herd with previously unknown Salmonella status. A longitudinal study of the three previously identified latently infected herds found seroprevalence ranging from 23.9% to 83.4% in sows after farrowing. Salmonella findings from faeces in the farrowing sections ranged between 1.8 and 24.5, and in the environmental samples between 0 and 25. In weaned piglets, Salmonella findings from faeces ranged from 6.3 to 48.0, and in environmental samples from 0 to 90%. The most prevalent serotypes were S. Derby (56.8) and S. Typhimurium, phage type DT104 (18.5). The seroprevalence comparison in sows and slaughtered fattening pigs revealed variations in the course of Salmonella infection in swine herds.

The volatile organic compounds (VOCs) in the packing of chicken meat in a modified atmosphere was qualitatively and quantitatively evaluated. The total number of 72 samples of chicken hindquarters were stored under two different modified atmospheres (70% O₂, 30% CO₂, and 70% argon, 30% CO₂) for 20 days. Analyses were performed on Days 0, 4, 8, 12, 16, and 20. VOCs in the headspace samples were detected and quantified by gas chromatography/mass spectrometry (GC/MS) every fourth day of storage. Pentamethylheptane, dimethylsulphide, dimethyl disulphide, dimethyl trisulphide, dimethyl tetrasulphide, hydrogen sulphide and ammonia were detected. Pentamethylheptane and ammonia had similar values for both modified atmospheres (MA). The other compounds were found only in argon MA from the Day 16 of storage with a subsequent increase of values. The measured values for dimethylsulphide were 10.7 and 13.8 mg/l, for dimethyl disulphide they were 1.9 and 10.7 mg/l, dimethyl trisulphide levels were 15.7 and 19.3 mg/l and dimethyl tetrasulphide levels were 93.2 and 418.3 mg/l for Day 16 and 20. The hydrogen sulphide level was detected from 80 to 370 mg/l after the 8^th day of storage. We showed that the argon MA is less suitable for packaging raw chicken parts than the oxygen MA in view of the increased amount of microflora and unpleasant odour as assessed by sensory analysis. Oxygen prolonged the shelf life by about four days in comparison with argon. Sensory evaluation was similar for both atmospheres after air exhaustion. The argon MA did not extend the shelf life as compared to the oxygen MA.

While several validated methods have been developed for analysis of phenylurea herbicides in staple food plants, analytical procedures suitable for their quantification in minor crops such as poppy seeds are not available. For the registration of isoproturon use in this crop, the documentation of dynamics of its residues following treatment was requested. To accomplish this task, HPLC-MS/MS method was developed. Extraction of residues was realised by methanol-water mixture, Supelclean LC-18 SPE cartridges were used for purification of crude extracts. For HPLC separation of isoproturon SPE fraction Lichrospher C18 column (25 cm × 4 mm, 5 μm) was employed. For detection and quantification of target analyte, mass spectrometer with ion trap analyser operated in positive atmospheric pressure chemical ionisation (APCI) and MS/MS mode was used. Following performance parameters of method were obtained: detection limit 0.01 mg/kg, recovery 84%, and repeatability 7%.

This work compared the use of polymerase chain reaction (PCR) and the conventional CSN/ISO/10272 culture-based methods in the detection of Campylobacter species in ready-to-eat meals made from chicken meat. PCR was carried out with the primers specific to C. jejuni, C. coli, C. lari, and was modified with an internal control. The detection of campylobacters by PCR was performed on both untreated and spiked samples of real food purchased in local stores. For PCR, the detection limit was 2 CFU/g after 48 h enrichment in Park and Sanders broth. Duplex PCR proved to be highly reliable in the detection of campylobacters in different food types. Without extra spiking, samples from a global fast food chain exhibited positive amplification of the PCR product while but negative results were obtained from the cultivation of the same samples.

The colour of the laboratory prepared pasta was evaluated with respect to wheat flour types (M1 bright, M2 semi-bright, and M3 semolina), egg-ratio (0, 1, 2), and non-traditional cereals (archaic wheat species, tritordeum, spring barley, millet, lupin, buckwheat, and soya) supplements. The flour colour measurement confirmed its dependence on the wheat species milled - M3 obtained from durum wheat had a lower whiteness L* (89.6) and a higher yellowness b* (22.2) than the flour from common wheat (e.g. 93.6 and 8.1 for M1, respectively). As presumed, with the rising egg-ratio pasta yellowness increased - for M1-pasta, the calculated colour differences ∆E in pairs one-egg/eggless and two-egg/eggless were 1.1 and 4.7, respectively, while for M2- and M3-pasta ∆E values were only 0.8 and 1.5, respectively. The colour impacts of non-traditional cereals as 10% supplements differed between archaic wheat species, tritordeum, barley, and alternative cereals (millet, lupin, roasted buckwheat). In comparison to the standard, the greatest positive colour gain was brought by the lupin fortification (130% yellowness increase), while the worst appesred roasted buckwheat (10% decrease of whiteness, 210% increase of redness). At 20% non-traditional cereals supplements compared for M2- and M3-pasta, the highest positive increase of the pasta colour sensory perception was caused by corn and lupin additions in both pasta samples. The increase was slightly higher with M1-pasta (175%) than with M3-pasta (170%). In the mean of both pasta samples, yellowness L* increased from the standard pasta value 13.6 to 24.0 as measured for corn and lupin fortified pasta.

Polyphenolic compounds are widely distributed in plants and are a common part of human diet. Polyphenols are known to be potent bioactive molecules, predominantly with protective effects. Many of xenobiotics, including polyphenols, influence the activities of various enzymatic systems. Such interactions can modulate the activities of co-administered drugs. The identification of polyphenols' potential for the interactions based on metabolic changes is thus necessary. Cytochrome P450, which takes part in the metabolism of more than 90% of used drugs, is an important enzymatic system which can be influenced. We therefore determined the influence of quercetin and trans-resveratrol on the activity of cytochrome P450 1A2 in rats. A perfused rat liver model and phenacetin as a marker of 1A2 activity were used. Moreover, we studied the dependence of trans-resveratrol's activity on sex in both sexes. Trans-resveratrol did not influence the 1A2 activity, but it enhanced sexual differences in the metabolic activity. Our results also confirmed different metabolic activities between sexes. Female rats metabolised faster through 1A2. Based on our results, we suggest that quercetin is an inhibitor of cytochrome P450 1A2 isoenzyme.

Certain physicochemical and sensory characteristics of the flavoured kefir drink were studied during refrigerated storage. Kefir drink batches were prepared using 2% addition of kefir grains, incubation for 18 h and subsequent filtration. The batches were then flavoured with blackberry, raspberry and strawberry aromas in the concentrations of 0.05, 0.10 and 0.15%, respectively. The samples were taken for analysis on 1^st, 4^th, 7^th, and 10^th days of storage at 4 ± 1°C. The sensory analysis of the flavoured kefir samples revealed the best acceptability level on the 4^th day of storage. Nevertheless, the samples were acceptable all throughout the storage. The percentage of the aroma addition significantly influenced the odour, flavour, texture, and mouth-feel, and the overall acceptability ratings. The higher percentage of the added aroma the more sensed, however, the lowest aroma addition was preferable. The pHs of the flavoured kefir drinks decreased throughout the storage time whereas, the titratable acidity, alcohol content and CO₂ values increased.

Germination is one of the most effective ways of preparing grain legumes for consumption. Because it involves the total or partial elimination of some anti-nutritional compounds, it is also one of the simplest methods of enhancing the palatability of grain legumes, thereby increasing their consumption as a valuable source of nutrition. The main objective of this paper is to describe the changes that take place in α-galactosides during germination. During germination, galactose molecules gradually become detached from α-galactosides due to the effect of the enzyme α-D-galactosidase activated during the process. To simulate the degradation of α-galactosides during legume seed germination, we applied nine equations to the evaluation of the experimental data obtained with the germination of three types of grain legume seeds; mung bean, chickpea, and lentil.

Echinacea species are popular herbal medicine and food supplements for enhancing the immune system. This study was conducted with the aim of developing an efficient heat reflux extraction of caffeic acid derivatives from dried adventitious roots of Echinacea purpurea obtained in bioreactor cultures. Water, methanol (20, 40, 60, 80, and 100%), and ethanol (20, 40, 60, 80, and 100%) were used as solvents for the extraction of caffeic acid derivatives. Another parameter used for the optimisation was the solvent temperature during extraction. The treatment of samples with 60% ethanol at 60°C for 2 h proved to be the most suitable procedure. This treatment was also responsible for the higher yields of total phenolics, flavonoids, and polysaccharides.

Polyphenols can greatly affect the sensorial characteristics and stability of wine. The concentration of polyphenols in wines is very low, the sample must be thus concentrated before the analytical measurement. The extraction on solid phase (SPE) is a suitable method for the isolation, purification, and concentration of polyphenols from complicated matrices. RP-HPLC with diode array detection was used for the separation and identification of polyphenols. A library of absorption spectra of standards was created and used for the identification of 14 polyphenols in wines. The contents of the individual polyphenols and their changes after the addition of four tannin preparations were determined in eight white and two rosé wine samples. The influence of the flavour profile of the applied tannin preparations on sensorial characteristics of wines was established

Two cultivars (Nicola and Saturna) largely distinguishing from each other in cooking behaviour and one cultivar (Agria) grown in six different cultivation regimes were tested by the CPEM (cooked potato effective mass) method for the potato sloughing assessment. The sloughing process is characterised by two cooking and disintegration stages, from which two basic CPEM parameters are derived: cooking time as the starting point of disintegration and the rate of the disintegration. Both parameters are analysed as functions of the tuber density in linear models of both stages. Significant differences in CPEM parameters and in the linear models were observed between different varieties. The data from two-year measurements were in basic agreement with our previous concept of the limited contribution of starch in the first cooking stage and of its more important role in the second disintegration stage of sloughing. The results indicated a close association between the mechanisms controlling sloughing and the tuber density in the cultivars Agria and Saturna. A different cooking behaviour was observed in the case of the typical salad cultivar Nicola with a considerably lower cooking time sensitivity to the tuber density.

Patatin relative abundance in SDS-extractable protein and patatin content in dry matter were evaluated in tubers of forty processing and table potato cultivars usually cultivated in the Czech Republic, Germany, and the Netherlands. The patatin characteristics were evaluated over three experimental years. Patatin relative abundance in the processing cultivars achieved on average a significantly higher value (P < 0.001; Tukey HSD test) than patatin relative abundance in the table cultivars, resulting in average values of 25.80% and 21.59%, respectively. A high patatin relative abundance (over 30% in extractable protein) was determined only in the case of two cultivars: Vaneda (average 31.29%) and Tomensa (average 31.24%). Patatin content in tuber dry matter was significantly higher in the processing potato cultivars in all three experimental years (P < 0.001), attaining a mean of 1.28% with the processing cultivars and 1.03% with the table cultivars. The direct effect of the cultivar on patatin relative abundance in SDS-extractable protein was higher (33.1% for processing potato cultivars and 48.1% for table potato cultivars) than the effect of the growing year (15.6% for processing potato cultivar and 22.8% for table potato cultivars).