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An innovative trend in the production of snack products is the use of selected vegetables for the production of dried vegetable chips. Beetroot is a suitable vegetable for this type of product, as it is characterised by its high biological potential and its content of a wide range of phytonutrients with beneficial effects on human health. The aim of this work was to compare five varieties of beetroot in terms of the content of total polyphenols and betacyanins, to assess the effect of hot-air drying on these important components and to determine the appropriate method of treatment of beetroot slices before drying in terms of improving the stability of polyphenols and betacyanins during drying. In this work, 5 beetroot varieties (Betina, Renova, Cervena kulata, Pablo F1, Karkulka) were evaluated. The beetroot chips were dried at 70°C until a residual moisture content of 15±1% was reached. To treat the slices before drying a 0.1% solution of ascorbic acid, 0.01% solution of CaCl2, 0.01% solution of K2S2O5, 1% solution of NaCl was used followed by blanching in a water bath at 96°C for 2 minutes. The highest content of total polyphenols and beta-cyanins was statistically significant (p<0.05) in the variety Pablo F1. During hot air drying, both polyphenols and betacyanins decreased significantly. The average decrease in betacyanins and total polyphenols was 50.97% and 48.70% respectively. To mitigate these changes, treatment with 0.1% solution of ascorbic acid and blanching appeared to be the most effective of the treatments tested. After treatment with ascorbic acid solution, the dried products retained on average 27.6% more betacyanins and 32.67% more total polyphenols than the control sample. [ABSTRACT FROM AUTHOR]

The aim of research was to verify variability of selected parameters of hygienic quality of chickpea spreads in relation to the used ingredients and storage conditions. Four basic groups of chickpea spreads (A, B, C, D) contained the same ingredients (boiled chickpea, salt, garlic). The decisive factor for assessing their hygienic quality was the addition of two different vegetable oils and lemon juice. The chickpea spreads were analyzed fresh, then after 24 and 48 hours of storage at a temperature of 4 and 8 °C. Using the plate dilution method was detected the presence of the total viable count (TVC), coliform bacteria, Bacillus cereus, microscopic filamentous fungi (MMF) and yeast. The following parameters were determined within the physic-chemical analyses: pH, water activity and salt content. The data were processed to the analysis of variance (ANOVA) in the general linear models (GLM), Scheffe's test and Pearson correlation coefficients (rxy). The presence of MFF and yeast in samples of chickpea spreads was minimal. A higher amount of yeast was detected in the spread with sunflower oil (B - on average of 4.9.10² CFU/g). The least amounts of coliform bacteria were found in the group of chickpea spreads with olive oil (<4.10¹ CFU/g). The presence of the bacterium B. cereus was not proven (<1.10¹ CFU/g). On the contrary, in chickpea spreads there was a higher representation of TVC (from 3.08 to 4.52 log CFU/g). High water activity (0.95 to 0.99) together with pH range (6.16 to 6.45), chickpea spreads are an ideal medium for the growth of various microorganisms. The average values of NaCl in fresh chickpea spreads were from 0.624 g/100 g (D) to 0.783 g/100 g (B). Most correlations between individual indicators in chickpea spreads were not statistically significant (P>0.05). A statistically highly significant difference between the two variables - pH and aw (P<0.01) was detected in sample A8b. The results showed that the chickpea spread with olive oil and lemon juice had the best properties in terms of safety. However, spreads represent an ideal environment for the growth of various microorganisms. [ABSTRACT FROM AUTHOR]

In the processing of tomatoes into juice and subsequently into puree, the key elements of the production technology are the heat treatment processes of the crushed tomato pulp and, in the production of puree, the way the tomato juice is concentrated, which can significantly affect the nitric quality of the final product. The aim of the work was to evaluate the dynamics of changes in carotenoid and polyphenol content occurring during processing of tomatoes into tomato puree by traditional and vacuum technology. The varieties used in the work for industrial processing were Uno Rosso F1, Pavlina, Mobil, Zomok and Denar. The tomatoes were sorted, washed and crushed after harvesting. The resulting pulp was heated at 93 ± 1 °C for 3 minutes and then passivated. Traditional concentrating was carried out by boiling at 95 °C until a soluble solids content of 29 °Brix was reached, while vacuum concentrating was carried out at 70 °C until a soluble solids content of 29 °Brix was reached. Total carotenoid content was determined according to the methodology of Hegedűs et al. (2016). Extraction of carotene from the homogenized samples was performed with acetone. The acetone extract obtained was repeatedly shaken with petroleum ether and the layers were dispersed with distilled water. The carotenesaturated phase was then dried over anhydrous sodium sulphate, transferred quantitatively to a volumetric flask and made up to the specified volume with 25 mL of petroleum ether. The absorbance of the samples was measured spectrophotometrically on a JENWAY spectrophotometer (6405 UV/VIS) at a wavelength of 450 nm. Determination of total polyphenols was carried out by the Folin-Ciocalteau method. The method is based on the reaction of Folin-Ciocalteau reagent with the polyphenols present in the sample analyzed to form a blue colored product. Sample preparation for polyphenol analysis consisted of homogenization and extraction in 80% ethanol. The polyphenol content was measured spectrophotometrically at 765 nm using a Jenway spectrophotometer (6405 UV/VIS). The total polyphenol content was calculated from the gallic acid calibration curve (GAE) at a concentration of 50 - 800 mg/L. Tukey's HSD multiple comparison test at P < 0.05 was used to assess statistically significant differences between variants. By processing tomato fruits into tomato juice, we found that the carotenoid and polyphenol content decreased statistically significantly (P < 0.05) after processing the fruits into tomato juice. A further decrease in the content of the evaluated parameters continued during the production of tomato puree by traditional thickening technology, while concentrating in vacuum had a demonstrably positive effect on the evaluated parameters and ultimately resulted in a renewed increase in the carotenoid and polyphenol content. In the evaluation of the dynamics of changes in carotenoids, we found an average decrease of 8.28% after processing the fruits into tomato juice, the concentrating of tomato juice on the traditional technology meant a further decrease of 28.88% in the content of total carotenoids compared to the fruits, but after using the vacuum concentrating technology, we found an increase of 9.97% in the content of total carotenoids compared to tomato juice, and the content of carotenoids was almost at the original value of the fresh fruits. By Tukey's test, we found a statistically significant (P < 0.05) effect of tomato processing method on the content of total carotenoids. By monitoring the polyphenol content, we found that polyphenols are more vulnerable than carotenoids. In the stage of concentrating tomato juice to puree by traditional technology, the polyphenol content decreased by an average of 27.71% compared to fresh fruits, while concentrating by vacuum technology recorded a re-increase in polyphenol content by an average of 23.84% compared to juice, to a content almost identical to that of the fresh fruits. When processing tomato fruit into tomato puree, based on the results of our work, we can clearly recommend producers to prefer processing juice into puree by vacuum technology over the classical technology of thickening under oxygen. After vacuum thickening of the puree, there are ultimately only minimal changes in the content of nutritionally significant components compared with fresh raw material. [ABSTRACT FROM AUTHOR]

The current research focuses on sensory and textural properties and color changes of soft meat products (frankfurters), which we observed on days 1 and 21 of storage. We incorporated chokeberry extract into frankfurters as natural antioxidants. We used two concentrations of extracts (3 mL kg-1 and 5 mL kg-1), the control with the addition of vitamin C and negative control. A colorimeter and instrumental texture analyser were used to create the texture and color profiles. At the beginning of storage, the group with added vitamin C had the lightest L* parameter, and there were no statistically significant differences between the a* and b* parameters. After 21 days, the values of all color parameters decreased. When determining textural properties, no negative effect was observed after the addition of extracts. According to sensory evaluations, the groups supplemented with natural antioxidants, and the control supplemented with vitamin C improved consumer acceptability and preference. [ABSTRACT FROM AUTHOR]

In purpose to examine the antioxidant activity of 15 natural honeys of different origin ABTS method was used, total phenol content and dry matter content of honey samples were determined. Honeys were collected from different locations of Slovakia, Poland and Serbia and were represented as monofloral and multifloral samples (10) which originated from Poland and Slovakia, forest samples (4) originated from Serbia and honeydew honey. Average values of antioxidant activity observed in samples of honeys ranged from 0.62 to 4.63 mmol/kg. The highest antioxidant activity was detected in buckwheat honey and the lowest was shown in acacia honey. By observing the impact of individual honey samples on antioxidant activity it was found that the sample had a highly statistically significant effect. 10 homogeneous groups which varied in the antioxidant activity among each other were established by all 15 samples. Antioxidant activity of honeys could be a positive influence factor in terms of honey differentiation, especially in the case of the forest honeys collected from different places. Monofloral and multifloral honeys (10) established 5 homogenous groups, but in the case of several multifloral honeys which originated from different places of Poland and Slovakia no statistically significant differences were found.

The aim of the work was to evaluate the effect of hot air and infrared drying on the content of total polyphenols and anthocyanin dyes in selected types of small fruits. In the work we used chokeberry (Aronia melanocarpa Michx.) variety Nero, elderberry (Sambucus nigra L.) variety Haschberg, sour cherry (Prunus cerasus L.) variety Fanal, red currant (Ribes rubrum L.) variety Lake, black currant (Ribes nigrum L.) variety Triton, cherry elaeagnus (Elaeagnus multiflora Thunb), raspberry (Rubus idaeus L.) variety Heritage and blueberry (Vaccinium corymbosum L.) variety Bluecrop. Drying was performed in a Concept S1060 hot air dryer and a Yden CI IR D5 infrared dryer. The analysis of the content of anthocyanin dyes was performed by the pH differential method, the determination of the total content of polyphenols was performed by the Folin - Ciocalteu method. By analyzing fresh fruits, we found the highest content of anthocyanin dyes in the fruits of chokeberry (3036.97 mg.100 g-1 DM) and the lowest in the fruits of cherry elaeagnus (83.86 mg.100 g-1 DM). The total polyphenol content ranged from 726.07 mg GAE.100 g-1 dry matter (cherry elaeagnus) to 7895.61 mg GAE.100 g-1 DM (chokeberry). After drying in a hot air dryer, the content of anthocyanin dyes decreased by 62.20% (in elderberry) to 72.52% (in cherry elaeagnus) and the content of total polyphenols by 45.16% (in chokeberry) to 53.34% (in red currant). After drying in an infrared dryer, the decrease in the content of anthocyanin dyes was 50.41% (in elderberry) to 71.22% (in cherry elaeagnus) and total polyphenols 41.05% (in chokeberry) to 47.89% (in sour cherry). [ABSTRACT FROM AUTHOR]

The meat industry in recent years leaning towards the replacement of synthetic antioxidants, such as BHT, for natural, mostly plant-based alternatives. For such purpose, polyphenol-rich plant species are selected and researched. Amelanchier (Amelanchier alnifolia) fruit seems to be an interesting option for adding to meat products to increase oxidative stability. In our study, we incorporate 3 and 5 ml of Amelanchier extract into pork sausage and observed changes in pH, color, sensory, and oxidative stability for 21 days period of vacuum storage. During storage period we measured pH values, color (expressed as cieLab coordinates), malondialdehyde concentration. Also, sensory evaluation was conducted. We compared those experimental meat products with sausages without any antioxidant and commercially used synthetic vitamin C. In our study we did not observe negative effects of Amelanchier extract addition compared to control groups in terms of pH, color and sensory properties. Regarding oxidative stability, Amelanchier extract was able to retard oxidation processes at comparable rate as vitamin C. Amelanchier therefore shows promising possibilities for food industry. However, further study of this natural resource is still needed. [ABSTRACT FROM AUTHOR]

The suitability of a barley grain for malt production depends upon a large number of quality parameters that are crucial for the identification of high-quality malt varieties. The grain and malt technological quality parameters of five samples of four spring malting barley varieties were studied in order to estimate their malting potential. Selected barley varieties proved to be of satisfactory malting quality in terms of analyzed technological parameters. First-class grain percentage in the analyzed samples ranged from 84.9 to 94.6 %. Hectoliter weight reached values from 634.2 to 737.1 g.dm-3. Barley samples also contained a relatively high starch content of 63 to 68 %. Nitrogenous substances ranged from 9.9 to 11.3 % and all tested varieties met the requirement for nitrogen content. These samples were micro-malted and resulting malt was analyzed. All tested malt samples achieved high and satisfactory extract content of 82.4 - 84.3 %. Statistically significant (p<0.05) the highest extract content was confirmed in variety LG Tosca (84.3 %) which was found to be relatively the best technological quality also for its kernel size and optimal starch and protein content. The average value of friability was 98 %. The intensity of proteolytic modification among varieties was satisfactory (Kolbach index 39.18 - 47.17 %). The viscosity of the wort reached values from 1.41 to 1.47 mPa.s-1, varieties provided clear wort in all cases. Based on the results of grain and malt quality parameters it can be concluded that all tested spring barley varieties are suitable for malting process. [ABSTRACT FROM AUTHOR]

In recent years we notice customers demand for substitution of synthetic food additives, such as antioxidants, for natural and possibly healthier options. Lipid oxidation is the most important meat deterioration process. To retard the oxidation meat industry use variety of synthetic antioxidants. However, due to recent customer demands, industry is trying to replace those synthetic antioxidants for their natural counterparts. This is a challenging process because not only new additives must adequate antioxidant ability, but it also cannot alter sensory quality of products. Fruit extract seems to provide such an option. In our study, blackcurrant (Ribes nigrum L.) and Kamchatka honeysuckle (Lonicera caerulea var. kamtschatica) was incorporated into raw-cooked meat products (Frankfurters). Frankfurters were vacuum packed and stored at 4 °C for 21 days. During the storage period no significant differences in pH was recorded, with average value of 5.54. Also texture analysis did not reveal differences between the control and experimental groups. Both extracts decrease the amount of malondialdehyde (MDA) created in samples. Control groups increase of MDA levels at the end of storage was 108%, blackcurrant and honeysuckle extract groups were just 44 and 39% respectively. Sensory evaluation however revealed that honeysuckle extract altered taste of final product in significant way. This could pose a problem with customers’ acceptance of such a product. [ABSTRACT FROM AUTHOR]

Saccharides are the basic dry matter components of all fruits and vegetables. The dominant tomatoes saccharides are fructose and glucose, minor ones are sucrose but also arabinose, xylose, and galactose. The objective of this paper is to analyze carbohydrates such as glucose, fructose and sucrose in the selected tomatoes varieties intended for the direct consumption and industrial processing. We used 14 varieties and 3 newly selected tomatoes varieties. The glucose content in the studied varieties was in the range of 4.87 – 15.9 g.kg-1, the fructose content was 11.1 – 22.27 g.kg-1 and sucrose content was 0.07 – 1.73 g.kg-1. The highest fructose and sucrose content was detected in the Tomanova variety, the highest sucrose content was found out in the Bovita variety. When comparing the glucose content it was found out that the higher content on average was achieved in the varieties intended for the industrial processing (10.10 g.kg-1) than in the varieties for the direct consumption (7.96 g.kg-1). The varieties intended for industrial processing were generally characterized by higher glucose and fructose content than the varieties intended for the direct consumption. When comparing the fructose content, we found a higher average content in the varieties intended for industrial processing (15.70 g.kg-1) than in the varieties for the direct consumption (14.40 g.kg-1). In most of the studied varieties sucrose was present in low content (<1.0 g.kg-1), only in the Tomanova variety sucrose content represented more than 1 g.kg-1. [ABSTRACT FROM AUTHOR]

Tomatoes are the most commonly preserved vegetables in the world. Traditional tomato products are tomato juice, puree or ketchup but demand for dried tomatoes is increasing at the market. Drying is one of the oldest methods of preservation and often accompanies the degradation of nutritionally important ingredients. In order to protect nutrients from excessive oxidation during drying, the right choice of the drying temperature and the treatment of the raw material prior to drying are important elements of the manufacturing process. In our work we investigated the impact of various ways of antioxidant treatment of the raw material before drying on the stability of total carotenoids, polyphenols and antioxidant activity of the product. We used Uno Rosso F1 cultivar of tomatoes, dried by air at 70 °C, and the fruits were cut into slices of 3 mm thickness. To increase the stability of phytonutrients, we used the slice treatment prior to drying with 1% potassium bisulphite, ascorbic acid, citric and acetic acid and 5% sucrose and sodium chloride solutions. We found that the 1% solution of ascorbic acid was the most effective in protecting of total carotenoids and polyphenols. In the protection of total polyphenols, acetic acid and potassium bisulphite solutions were equally effective. The most significant increase in antioxidant activity was found to be ascorbic acid solution. [ABSTRACT FROM AUTHOR]

Fruit and vegetable waste represent a significant source of nutrients, such as polyphenols, minerals, fibre etc. For the food industry, they make a huge contribution from an economic point of view. In our work, we observed the by-products of plant processing as possible local sources of biologically active componets for the further application in gluten-free products. The total polyphenols, antioxidant activity and crude protein in eight samples of plant by-products (apple, buckwheat, tomato, chilli and grape varieties of Irsai Oliver, Red Traminer, Alibernet, Cabernet) were determined. The crude protein content ranged from 1.4% in buckwheat pomace to 15% in chilli pomace. The highest polyphenol content was found to be in Alibernet grape pomace (256.9 mg.kg-1) and the lowest in chilli (155.15 mg.kg-1) pomace. The antioxidant activity of pomace ranged from 535.2 to 1359.49 mg.dm-3. Gluten-free products such as muffins and knäckebrots were designed, into which by-products were applied in the amount of 3%, except for chilli (0.5% addition). Developed gluten-free products were evaluated by sensory and texture methods. As the sample with the highest sensory quality were concluded to be muffins made with 3% addition of Cabernet pomace. Grape and apple pomace can be recommended in gluten- free muffin production and tomato pomace in gluten free knäckebrot production. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the effect of GSE application on quality (oxidative stability, color and sensory quality) of rawcooked meat products stored 10 days at 4 °C. Antioxidant activity assessment of applied GSE of different grape varieties in Frankovka modrá (E2) grape varieties was observed higher antioxidant activity (91.2%) than that in Dunaj (E1) and Cabernet Sauvignon (E3) grape variety (85.3, resp. 85.8 %). At the end of storage (day 10), we observed higher oxidation stability in all experimental groups with grape seed extract supplements and therefore a lower MDA value compared to the control group without the addition of extracts. In control group was recorded the highest production of MDA (0.129 mg.kg-1). From experimental groups with the addition of different grape seed extracts, we recorded the highest degree of oxidative stability in the experimental group with the addition of Frankovka modrá extract (0.115 mg.kg-1). The highest degree of oxidative damage from all experimental groups was found in group with the addition of Dunaj extract (0.120 mg.kg-1). The MDA content in the experimental group with the addition of Cabernet Sauvignon grape extract at the end of the refrigeration storage period was 0.118 mg.kg-1. In the evaluation of the individual sensory quality indicators after grape seed extract we did not record statistically significant differences (P> 0.05) between individual groups, indicating that the sensory quality of rawcooked meat products was not negatively affected by their addition. In the evaluation of the most important indicator of sensory quality (taste) we recorded better average ratings in all experimental groups with the addition of grape seed extract than in the control group. Based on the results of the oxidative stability and sensory quality of the raw-cooked meat product after 10 days of refrigerated storage at 4 °C, we can recommend using natural antioxidants in the production of the meat product in the form of grape seed extract Dunaj, Frankovka modrá and Cabernet Sauvignon to increase oxidative stability thereby increasing the shelf life and sensory quality of the rawcooked meat product. [ABSTRACT FROM AUTHOR]

The colour and limpidity are the first sensory attributes of wines that are appreciated by consumers, predisposing their acceptance or rejection. The aim of this work was to monitor the effect of harvest, processing (different clarification and treatment of must) and storage on the quality of Sauvignon wine. The wines were stored for two years in the wine cellar at 12°C and 70 % of humidity, in the bottles. The acid content, residual sugar and alcohol content among chemical parameters and sensory profile of wines were observed. Sensory quality of wines was evaluated by the aromatic profile (profile method). Based on acquired results, two years of wine storage significantly affected the total acid content of wines and alcohol content. Different treatments of must affected residual sugars, the variant with the maximum dose of the clarification preparation (highly pure cellulose, polyvinylpolypyrrolidone, gelatin and mineral adsorbents) showed statistically the highest content of residual sugars. From the sensory point of view, sensory profiles of wines were different compared to the first and second harvest of grape, sensory profiles of wines were changed also after two years of storage. The fourth variant appeared to be the best stable, treated with the addition of clarification preparation at the dose of 30 g. 100 L-1 must. Because from the same variety Sauvignon were produced wines of different chemical and sensory qualities, some gastronomy recommendations were done as well. [ABSTRACT FROM AUTHOR]

To one of the most valuable pumpkin fruit belongs winter squash (Cucurbita moschata Duch). The aim of this work was to assess the quality of C. moschata fruit and to assess the dynamics of compositional changes after the heat treatment of the pulp. We used six varieties Liscia, Orange, Hannah, UG 201 F1, Waltham, Serpentine. In the samples were analyzed carbohydrate content (glucose, fructose and sucrose), total polyphenols, total carotenoids and antioxidant activity. The fresh pulp and pulp after the heat treatment were observed. Content of carbohydrates was determined by FTIR infrared spectroscopy. Content of total carotenoids, polyphenols and antioxidant activity was determined by spectrophotometry. As the dominant sugar was found to be sucrose. The lowest content of all carbohydrates was found in the variety Serpentine. Fructose content ranged from 7.59 to 12.32 g.100 g-1 dry matter, glucose content from 7.23 to 9.79 g.100 g-1 dry matter and sucrose content 38.67 to 55.94 g.100 g-1 dry matter. After processing there was found a decrease in the sucrose and the slight increase in glucose and fructose content. Total carotenoid content in fruits ranged from 39.01 to 97.67 g mg.100 g-1 dry matter, the content of total polyphenols from 443.98 to 565.44 mg GAE.100 g-1 dry matter and antioxidant activity from 680.18 to 851.87 mg AA.100 g-1 dry matter. After the heat treatment, there was found some decrease in total carotenoids, polyphenols and antioxidant activity as well. [ABSTRACT FROM AUTHOR]

In the present study we aimed to evaluate the oxidative stability of Spiš frankfurters after application of grape seeds extracts (Blauburger + Cabernet Sauvignon and Danube) in amount of 10 mL.kg-1 during 12 days of their storage at 4 °C. Sensory evaluation of Spiš frankfurters was carried out after 4 days of storage by 6-point ranking system (Surface appearance and color, appearance and color when cut, texture, aroma and flavor). It was found that sensory quality of Spiš frankfurters was not significantly (p >0.05) affected by application of grape seed extracts. Oxidation stability of Spiš frankfurters after 12 days of storage at 4 °C was positively influenced (p ≤0.05) only in the group with addition of extract made from grape seed Blauburger +Cabernet Sauvignon. This may probably related with the higher antioxidant activity of extract of this variety (100.5%) compared to an extract made from grape seed variety of Danube (55.8%). Also, it was not found significant differences (p >0.05) of antioxidant activity between extract made from grape seeds variety Danube compared with the control group. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate textural changes in carrots during cooking and to find optimal cooking time of carrots. Using a TA.XT Plus Texture Analyser, texture profile analysis (TPA) of carrot hardness, springiness, cohesiveness, gumminess and chewiness after 5, 10, 15 and 20 minutes of cooking was performed. The highest value for hardness was observed in raw carrot (10167.5 g). The lowest value for hardness (1378.92 g) was observed after 20 minutes of thermal processing. Using the Analysis of Covariance (ANCOVA), it was found out how carrot hardness during cooking varies with the other textural parameters from TPA analysis. The coefficient of determination was 0.9955 and it explained 99.55% of total variability for the TPA analysis results. The highest differences in hardness were observed in the first 5 minutes of cooking. The significance of the model was determined by The Fisher's F test. The probability corresponding to the F value was lower than 0.0001, it would be taking a lower than 0.01% risk in assuming that there was no effect of the explanatory variables. The results implied that the optimal cooking time of carrots lies in range of 10 and 15 minutes. [ABSTRACT FROM AUTHOR]

In the Slovak Republic currants are traditionally grown species of small fruits mainly in house gardens. Although currently their area is very small compared to the other types of fruit. We can see the importance of growing this genus (Ribes L.) in its good adaptability to climate conditions, in small growing demands and in stable production of nutritionally highly valuable fruit. Currant berries as well as fresh currant juice are characterized by the presence of whole complex of antioxidant active substances. The aim of this study was to evaluate the nutritional quality of currant juice prepared from various species and varieties of genus Ribes (L.). based on the content of their total polyphenols, anthocyanin dyes and antioxidant activity. In work we used varieties Blanka, Primus, Viktória, Heinemannova neskorá, Red Lake, Treny, Jonkheer van Tets, Fertödi, Titania, Triton and Öjebyn. Contents of evaluated components were assessed spectrophotometrically. Total polyphenol content of monitored samples determined by the Folin-Ciocalteu method reached values from 1897.43 mg GAE.dm-3 DM to 3712.21 mg GAE.dm-3 DM. The highest one was in juice from variety Primus and the lowest from variety Blanka. In white varieties of currant, the presence of anthocyanin dyes was immeasurable. In varieties of red and black currant anthocyanin dye content achieved values from 1947.64 mg.dm-3 DM (Jonkheer van Tets) to 4161.07 mg.dm-3 DM (Heinemannova neskorá). The antioxidant activity determined by the FOMO method reached values from 4130.42 mg AA.dm-3 DM to 6571.69 mg AA.dm-3 DM. We recorded the highest antioxidant activity in juice of variety Fertödi and the lowest of variety Primus. [ABSTRACT FROM AUTHOR]

Due to the content of biologically active substances, sea buckthorn (Hippophae rhamnoides L.) has become the object of great interest of both, experts and the general public. It is appreciated particularly for the high content of vitamins and other biologically active substances, not only in berries but also in leaves and bark. The aim of the study was to evaluate the nutritional quality of sea buckthorn juice prepared from different varieties of sea buckthorn based on the content of total carotenoids, polyphenols and antioxidant activity. In this study we used varieties Hergo, Tytti, Vitaminaja, Raisa, Askola, Dorana, Slovan, Leikora, Bojan, Terhi and Masličnaja. Content of different components was quantified using spectrophotometry. The total carotenoids content expressed as β-carotene content in juice ranged from 50.63 mg.100 g-1 DM to 93.63 mg.100 g-1 DM, the highest content was in variety Askola and the lowest one in Terhi. Total polyphenols content determined by Folin-Ciocalteu method ranged from 13.03 mg GAE. dm-3 DM to 25.35 mg GAE. dm-3 DM. The highest content was identified in juice of variety Dorana and the lowest one in Raisa. The antioxidant activity quantified by the FOMO method ranges from 45.11 g AA. dm-3 DM to 108.77 g AA. dm-3 DM. The highest antioxidant activity was determined in juice of Dorana and the lowest in variety Bojan. [ABSTRACT FROM AUTHOR]

In the current food industry, companies often offer new and revolutionary processing methods that allow to improve food properties. A prominent technology is High Pressure Processing (HPP), a non-thermal technology that arises as an alternative to the traditional thermal pasteurization (TP). With HPP it is possible to obtain food and drinks similar to the raw food while improving important nutritive and functional properties. Since strawberries are very important fruit in the human diet, the aim of this study was to study the effect of HPP and TP on selected qualitative-quantitative parameters of strawberry juices (HPSJ - High Pressure Strawberry Juice/TPSJ - Thermal Pasteurized Strawberry Juice). It seems that strawberries can have a positive effect on human health due to their high content in beneficial nutrients. From monitored parameters, significant differences (p <0.001) were found between juices in the following parameters: antioxidant activity, β-carotene and zeaxanthin content. Higher antioxidant activity (1547.60 ±4.89 mg AA.L-1 FM vs. 1424.72 ±10.66 mg AA.L-1 FM) and zeaxanthin (1.34 ±0.11 μg.mL-1 FM vs. 0.89 ±0.08 μg.mL-1 FM) was found in HPSJ, comparatively to TPSJ. The content of β-carotene was higher in TPSJ (156.28 ±2.13 μg.mL-1 FM) than in HPSJ (122.02 ±4.28 μg.mL-1 FM). Results related to the polyphenols content showed significantly higher values (p ˃0.01) in HPSJ, compared to TPSJ (1100.04 ±17.16 mg GAE.L-1 FM vs. 1002.66 ±17.16 mg GAE.L-1 FM). The difference in the content of lutein (TPSJ 8.84 ±0.57 μg.mL-1 FM; HPSJ 8.17 ±0.13 μg.mL-1 FM) was not significant (p ˃0.05). [ABSTRACT FROM AUTHOR]

The aim of study was to determine primary and secondary metabolites in selected varieties of potatoes. Potatoes (Solanum tuberosum L.) are good source of bioactive compounds, mainly phenols as one of the most important components. The chemical composition with reducing sugar, starch, ascorbic acid, total polyphenol and flavonoid content were analysed in five potato varieties (Agria, Marabel, Red Anna, Picasso, Princess). Values of dry matter content ranged from 20.34 to 23.64%. In terms of tubers storage, its content above 20% is required. The highest level of starch was detected in variety Princess (16.82%). The lowest reducing sugar content was recorded by variety Marabel (0.08%). Similarly, low values reached varieties Princess (0.12%), Agria (0.14) and Red Anna (0.16%). These would be appropriate to use for food processing and for production of fried potato chips or fries. Variety Red Anna reached the highest amount of vitamin C (73.72 mg.kg-1). The lower levels of this vitamin showed tubers of varieties Picasso (35.02 mg.kg-1) and Princess (36.89 mg.kg-1). The antioxidant activity was measured with radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical as well as phosphomolybdenic assay. Potato varieties contained high levels of total polyphenols (0.474 - 1.550 mg GAE per dry weight) and flavonoids (1.407 - 15.933 μg QE per dry weight). The consumption of potatoes can provide nutritional value along with antioxidant potential that can be helpful for proper functioning of the body physiological systems. Statistical evaluation by the single factor analysis of variance detected high significant impact of variety on the content of all the analytical parameters in evaluated varieties of potato tubers. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the polyphenol and flavonoid content, electrical conductivity and color measurement of 15 natural honeys. Honey samples were collected from different locations of Slovakia (6 samples), Poland (5 samples) and Serbia (4 samples) and were obtained directly from local beekeepers. The mean content of polyphenolic substances ranged from 611.2 to 2962.24 mg.kg-1. Multifloral honeys were shown to be a good source of TPC, they ranged from 611 to 1257.12 mg.kg-1, those of the samples originated from Poland showed 611 to 990 mg.kg-1, and from Slovakia 703.7 to 1257.12 mg.kg-1 TPC. Forest honeys were found to be also good source of TPC, they ranged from 769 to 1052 mg. kg-1. High correlation was found between TPC and flavonoid content (r=0.92). Mean content of flavonoids in the honeys expressed as rutin content ranged from 112.46 to 846.58 mg.kg-1. Multifloral honeys ranged from 112.49 to 592.35 mg.kg-1, those of the samples originated from Poland proved 112.49 to 189.13 mg.kg-1 flavonoids, and from Slovakia 127.48 to 592.35 mg.kg-1. Forest honeys as a source of flavonoids were proved to be from 136.48 to 266.79 mg.kg-1. Objective measurement of honey color was performed by the L*a*b* system. [ABSTRACT FROM AUTHOR]

The objective of a comparative study was to investigate the relationship between the sensory assessment of the varietal coffee samples and their aromatic profile measured using an electronic nose. Sensory analysis plays a very important role in the evaluat ion of food especially in the evaluation of plant products (coffee included). Sensory assessor's role is to assess the taste, smell, texture and visual attributes of the product. Equally useful in the objective evaluation of foods and their flavor profile appears to be an electronic nose. The study showed that there is a difference in a flavored coffee varietal profile. This study was performed using techniques TDS for 15 seconds by naïve panel. Most of the coffee samples appeared bitter with sour aftertaste. Flavors of coffee are also often linked with its taste. The aim of measuring the electronic nose was thus instrumental to detect similarities between the seventh varietal coffees. The results showed that the similarity between human measurement panel and substantiating the electronic nose. Data were reduced using PCA techniques and most of the samples correspond to the same position at both assays. [ABSTRACT FROM AUTHOR]