Potravinarstvo Slovak Journal of Food Sciences
Not a member yet
1254 research outputs found
Sort by
Evaluation of vapor-phase antifungal activities of selected plant essential oils against fungal strains growing on bread food model
Get PDFThe current study aimed to investigate antifungal activities of two commercially available essential oils (EOs), specifically Tea tree oil (Melaleuca alternifolia; TTEO) and St. John's wort oil (Hypericum perforatum; HPEO) against three Penicillium (P.) species: P. citrinum, P. expansum, and P. crustosum in in situ conditions. For this purpose, EOs were applied in the vapor phase to determine the growth inhibition of fungi artificially inoculated on sliced bread. Changes in colony growth rate were evaluated as markers for the mycelial growth inhibition (MGI) effect of the EOs. The antioxidant activities of the EOs were evaluated using the DPPH method. The moisture content (MC) and water activity (aw) of bread as a substrate for fungal growth were also measured. From the DPPH assay, we have found that both EOs (TTEO, HPEO) exhibited strong antioxidant activity (64.94 ±7.34%; 70.36 ±1.57%, respectively). The values for bread MC and aw were 43.01 ±0.341% and 0.947 ±0.006, respectively. Our results suggest that HPEO is the only weak inhibitor of P. citrinum and P. crustosum colony growths. Also, the highest concentrations of TTEO display only the weak capability of mycelial growth inhibition of P. citrinum and P. crustosum. By contrast, the colony growth of P. expansum was enhanced by both EOs at all levels used. In conclusion, the application of both EOs in the vapor phase against selected Penicillium species seems not to be a promising alternative to chemical inhibitors used for bread preservation
The study of the variability of morphobiological indicators of different size and weight groups of hybrid silver carp (Hypophthalmichthys spp.) as a promising direction of development of the fish processing industry
Get PDFIn water reservoirs, the size and characteristics of fish, in the first place, affect – the composition and clarity of food objects, the number of food competitors and predators, their numbers, industry, and others. Besides, the rate of linear and weight growth are the arteries that determine the value of the species as an object of commercial fishing. The hybrid of silver and bighead carp easily adapts to different growing conditions (from the point of view of the formation of fish-biological indicators), protein in different years depending on feeding conditions, in one reservoir indicators of length and body weight of ribs are inadequate. Evaluating the influence of feeding conditions on the linear growth of the rib, the method of generalized evaluation was used. An indicator equal to the sum of potential fish productivity for phyto-zooplankton was used to characterize the foraging status of a particular condition in a certain period. In terms of the quality of growth indicators, the indicator of the absolute weight of nature with differentiation of farms, age groups, and years was used. The results of the research revealed significant variability in the size and weight characteristics of different groups of silver and bighead carp, which were isolated from ponds and reservoirs. According to the results of experimental studies established for the cultivation of hybrid silver and bighead carp in reservoirs, relatively high rates of linear and weight growth are expected, higher than for similar species, which is provided in the conditions of fish ponds
The microbiological quality of minced pork treated with garlic in combination with vacuum packaging
Get PDFThe present study aimed to evaluate the microbial quality of minced pork treated with fresh garlic, dried garlic, and garlic oil in combination with vacuum packing. The growth of Total Viable Counts (TVC), Coliform Bacteria (CB), and Pseudomonas spp. were evaluated. The microbiological analyses were performed by the plate dilution method. The average value of TVC was 8.45 log CFU.g-1 in aerobically packed samples, 5.59 log CFU.g-1 in samples treated with garlic oil, 5.36 log CFU.g-1 in vacuum packed samples, and samples treated with dried garlic, and 4.98 log CFU.g-1 in samples treated with fresh garlic on 8th day of storage. The number of TVC was significantly lower in samples treated with fresh garlic compared to samples treated with dried garlic and garlic oil on the 8th day of storage (p <0.05). The average value of CB was 4.13 log CFU.g-1 in aerobically packed samples, 1.82 log CFU.g-1 in samples treated with garlic oil, the value of CB in vacuum packed samples, in samples treated with fresh garlic and also with dried garlic was lower than 1.00 log CFU.g-1 on 8th day of storage. The number of CB was significantly higher in aerobically packed samples and samples treated with garlic oil compared to vacuum-packed samples, samples treated with fresh garlic and dried garlic on the 8th day of storage (p <0.05). The average number of Pseudomonas spp. was 2.45 in aerobically packed samples, count of Pseudomonas spp. was lower than 1.00 log CFU.g-1 in vacuum packed samples and in the sample with garlic on the 8th day of storage. The number of Pseudomonas spp. was significantly higher in aerobically packed samples in comparison with vacuum-packed samples, samples with fresh garlic, dried garlic, and garlic oil (p <0.05)
The influence of varietal characteristics on the quality indicators of candied fruits from plum fruits
Get PDFThe influence of varietal characteristics of plum fruits on the physicochemical parameters of the drying process has been investigated. Revealed significant differences in the content of biologically active compounds on the example of varieties: Stanley, Big Stanley, Grossa di Felisio, President, Blue moon, August Delish, Kabardinskaya early. The consumption rates of raw materials for the production of candied fruits have been determined. The results of laboratory studies on the variation of the content of vitamins (C, P), anthocyanins in plum fruits, taking into account varietal characteristics, are presented. The drying process on a dryer with infrared rays led to a slight decrease in polyphenolic and mineral substances, and higher losses of vitamins in the finished candied fruit. The mathematical processing of the experimental data was carried out by the method of analysis of variance and descriptive statistics using the Microsoft Excel software package. In the production of candied plum fruits, optimal technological modes have been selected that contribute to a high yield of high-quality finished products, taking into account the varietal characteristics of the feedstock. According to biochemical and organoleptic indicators of the quality of candied fruits, Stanley and President varieties were distinguished, the energy value of which is 147.0 kcal with an organoleptic assessment of 4.9 points. The results of experimental biochemical and technological analyzes of fruits at individual technological stages of production made it possible to assess the intensity of complex processes that cause a qualitative transformation of raw materials
The antimicrobial activity of polyfloral honey and its awareness among urban consumers in Slovakia
Get PDFThe current interdisciplinary research studies the antimicrobial activity of selected polyfloral kinds of honey (n = 30) against three microorganisms (gram-positive bacteria Enterococcus faecalis, gram-negative bacteria Salmonella enterica, and one yeast Candida krusei) as well as investigates consumer behavior and awareness towards honey healing properties. Consumer research involved 617 honey consumers living in urban areas. T-test for Equality of means, non-parametric tests, and descriptive statistics were applied. Results showed that antimicrobial activity was found in all honey samples with a concentration of 50%. Nevertheless, better activity was obtained in honey samples from urban beekeepers compared to samples from retail stores. Results of consumer research showed that honey is mostly used as food (sweetener in beverages, ingredient in the recipe, or direct consumption) and as medicine mainly during the winter period. The consumer awareness towards honey healing effects was very high (97%), however, 1/3 of respondents were not able to list any specific examples, and only 11 % mentioned antibacterial activity. Furthermore, more than 70% of respondents did not know to explain the term “medical honey” and more than 50% of respondents are not aware of the maximum temperature used for heating honey without decreasing its biologically active compounds
Basil – a comparison of the total phenolic content and antioxidant activity in selected cultivars
Get PDFDuring the lifetime, the human body forms a considerable amount of free radicals damaging DNA, cell membranes, and their components. A wider application of basil (Ocimum basilicum), an aromatic plant and one of the common gastronomic commodities in the human diet could help to prevent the formation of free radicals and to remove them from the human body. Therefore, determination of antioxidant activity and total content of phenolic substances in selected cultivars of basil (Ohře, Sweet green, Salad leaf, Purple opal, Thai) in a fresh and frozen state and the mixture with another plant (garlic, mint, rocket, spinach) in the fresh and refrigerated state was performed. The total content of phenolic substances in basil was established by the spectrophotometric Folin-Ciocalteu method. DPPH spectrophotometric method was used to analyze the antioxidant activity. The results have shown statistically significant differences between basil cultivars under the same growing conditions. The values of antioxidant activity in frozen samples ranged from 5.1 ±0.4 mg.g-1 AA FW to 11.71 ±0.18 mg.g-1 AA FW and the total phenolic content varied between 2.77 ±0.16 mg.g-1 GAE FW in TH and 8.93 ±0.13 mg.g-1 GAE FW. A statistically significant difference between fresh and frozen samples was established only in the “Ohře” cultivar. After the storage in cold temperatures, all mixtures showed a reduction in the antioxidant activity and total content of phenolic substances. The mixture of basil and mint performed the highest values of antioxidant activity and total content of phenolic substances and significantly differed from the other mixtures most often. The addition of basil and its mixtures to food and beverages can substantially increase their biological value and subsequently also the quality of human nutrition
The use of secondary fish raw materials from silver carp in the technology of structuring agents
Get PDFThe expediency and prospects of using secondary fish raw materials from silver carp in the structuring agents technology have been substantiated. The combination of secondary fish raw materials and seaweed with different mechanisms of gelation has a targeted effect on the organoleptic, structural-mechanical, and physicochemical properties of food products. Accordingly, the expediency of adding the Black Sea alga cystoseira (2%) to optimize the mineral composition of the structuring agents and increase their jelly-making properties was established. Using experimental studies and multicriteria optimization, the optimal ratio of secondary fish raw materials – 40%; water – 60% and rational heat treatment – 150 min, at a temperature of 85 – 100 °C has been determined. An analysis and comparison of various preservation methods have confirmed the expediency of using the freeze-drying method of drying fish broths for the production of structuring agents, which allows to preserve of the original properties of the product, biologically active substances, reduce the mass of the dried product and increase the shelf life of the structuring agents. The optimal storage conditions have been determined – the ready-made structuring agents were packed in three-layer paper kraft bags and stored in a cool dry place at a temperature of 22 ±2 °C and relative humidity of no more than 70% for 12 months. It was found that the physical and chemical indicators of the structuring agents depend on the features of the structure, amino acid composition of fish collagen. The presence of the overwhelming number of high-molecular-weight molecules in the composition of the structuring agents and the preservation of the native structure determine high indicators of dynamic viscosity, dissolution time, and strength. As a result of the research, it was revealed that the high protein content largely depends on the amount of collagen in the secondary fish raw material, which has a positive effect on the gelling properties of the product being created
The technological properties of winter wheat grain during long-term storage
Get PDFIn the world, the demand for quality and safe grain products is increasing. The need to preserve wheat in the event of a natural disaster requires the study of optimal storage times of grain without degrading technological indexes. The purpose of the work was to study the dynamics of technological properties of winter wheat grown after peas, clover, corn for silage and the industrial, ecological, biological growing systems during 1, 3, and 5 years of storage in the conditions of the ordinary granary. The absence of significant differences in the technological parameters of the grain of wheat grown at industrial and ecological systems, but significantly lower indicators at a biological growing system was found. The highest hectolitre weight obtained when wheat grain was grown after corn for silage, and vitreousness – after the clover. Significantly higher biochemical parameters of grain and alveographic properties of flour were for the cultivation of wheat after peas, which provided additional accumulation of protein substances. There are no significant changes in the indicator of hectolitre weight during the grain storage. Other indicators increased significantly after 1 year of storage (on average by 10 – 30%). For further storage, vitreousness growth was insignificant. After 5 years of storage, the falling number significantly increased (on 21% compared to the initial values and on 7% – after 3 years of storage). The content of protein, gluten in the grain, and alveographic properties of flour significantly decreased after 5 years of storage. The possibility of obtaining grain of wheat with high technological parameters for a more safe ecological growing system was established. It was also confirmed to need for grain storage up to 1 year to improve quality indicators and it was established that it safely stored for 3 years
The potential of red dragon fruit peel yogurt to improve platelet levels in heparin-induced thrombocytopenia in Wistar rats
Get PDFPatients infected with the dengue virus will develop thrombocytopenia which can cause bleeding and complications. One of the materials that contain antioxidants and have potential as a functional food is red dragon fruit peel. This peel can be processed into yogurt as a way to increase antioxidant function which ultimately supports the immune system of its users. This study analyzed the effect of red dragon fruit peel yogurt on the platelet levels of thrombocytopenic Wistar rats. It used a pre-post-test control group design. Male Wistar rats were randomly assigned into seven groups: K-; K+; and five treatment groups that received dragon fruit peel yogurt at doses of 5% (K1); 10% (K2); 15% (K3); 20% (K4); and 25% (K5). Thrombocytopenia was induced by 0.1 mL.100g-1 BW of heparin for 3 days. The intervention was carried out for 28 days. The result showed that all groups had significant differences before and after the intervention (p <0.05). Tukey analysis showed that there were significant differences in all groups (p <0.05). Yogurt containing 25% red dragon fruit peel provides an effective dose for improving platelet levels in thrombocytopenic rats
The effect of single clove Black garlic on the hemostasis status and lipid profile in male Sprague Dawley rats with non-alcoholic fatty liver disease
Get PDFNon-alcoholic fatty liver disease (NAFLD) patients have alteration in hemostasis components. Thus, including excess expression of plasminogen activator inhibitor-1 (PAI-1), causing fibrinolysis disorders; the majority of these patients are hypercoagulable state prone to thrombosis. Some evidence suggests that garlic and garlic supplements have antithrombotic and anti-inflammatory properties. Besides, garlic stimulates fibrinolytic activity and normalizes plasma lipid imbalances. Black garlic is processed garlic that is produced through natural aging at a controlled temperature (70 °C) and high humidity (90%) for several days, without other additives. This study aimed to prove the effect of single clove black garlic (SCBG) (Allium sativum Linn) on PAI-1 levels and lipid profiles of NAFLD rats induced by a high-fat fructose diet (HFFD) containing 1.25% cholesterol and 0.5% cholic acid.The rats were then divided into healthy control group (K1+); NAFLD control group without treatment (K2+); 0.9 mg simvastatin treatment group (K1-); 45 mg metformin treatment group (K2-); SCBG 450 mg per 200g BW (X1); 900 mg per 200 g BW (X2); and 1350 mg per 200 g BW (X3). All treatments were administered for 4 weeks via oral gavage. As a result, significant differences in PAI-1 levels and lipid profiles between groups after the administration (p = 0.001) were noted and also by simvastatin and metformin, respectively. There was a correlation between PAI-1 and lipid profile of SCBG treatment. In conclusion, the administration of SCBG (1350 mg per 200 g BB per day) for 4 weeks had a significant effect on PAI-1 levels, and the lipid profiles in Sprague Dawley rats modeled NAFLD (p = 0.001). SCBG has provided benefits that can be useful in the management of NAFLD but it’s not equivalent to medicine