Potravinarstvo Slovak Journal of Food Sciences
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Fungal diversity in the grapes-to-wines chain with emphasis on Penicillium species
Get PDFThe aim of this work was the description of surface and endogenous mycobiota colonisation of grapes, fresh grape juice, grape must, and wine primarily focused to the current spectrum of the penicillium species. One sample of white grape variety Palava and one sample of blue grape variety Dornfelder were collected in Small Carpathian wine growing region of Slovakia in the year 2017. Direct plating of grapes on agar plates was used for analysis of surface mycobiota of grapes while surface sterilsed grapes were used for endogenous mycobiota analysis. Mycobiota of juice, must, and wine was analysed by plate dilution method. Overall, we isolated 148 strains belonging to 13 genera of filamentous microscopic fungi and Mycelia sterilia from grape variety Palava, while the most frequent was Alternaria. Alternaria was the most common genus in the surface and endogenous colonisation with an average relative density 50% and 73.6%, respectively. A total of 2 species of Penicillium were detected from the grapes to wine, potentially toxigenic Penicillium expansum and P. chrysogenum. A total of 39 strains belonging to 6 genera and Mycelia sterilia were identified from grape variety Dornfelder. The most abundant genus was also Alternaria (51.3%), followed by Penicillium (12.8%). Alternaria was the most common genus in the surface and endogenous colonisation and fresh grape juice with an average relative density from 20% (grape juice) to 71% (endogenous colonisation of grapes). A total of 3 species of Penicillium were detected from the grapes to wine, where Penicillium expansum were detected most commonly. In the second part of our work some selected isolates were tested to the ability to produce mycotoxins such as patulin, citrinin, and roquefortin C in in vitro condition by thin layer chromatography method. All tested strains of Penicillium species were able to produce at least one mycotoxin. 
Effect of additives to microbiological quality of yogurts
Get PDFThe objective of this work was to study the effect of addition chia flour, quinoa flour, nopal powder, apple fibre and bamboo fibre BAF 40 in yogurt to microbiological quality. Yogurts were made with 1, 3 and 5% of addition of these additives. The milk used for manufacturing was heated up to 85 °C for 5 min and flour, powder and fiber were irradiated for 20 min in three replicates. It was monitored: Lactic acid bacteria (LAB) - 72 hours at 30 °C (ISO 13721:1998) and yeasts and moulds - 5 days at 25 °C (ISO 21527-1:2009). During storage, the number of LAB was increased to match the initial concentration of yogurt with addition chia flour (concentration 1, 3, 5%) and quinoa flour (1%). The addition of nopal powder, apple or bamboo fiber to yogurt showed a tendency to decrease the number of LAB compared with its initial concentration. All samples were compared with the control yogurt without addition whatever flour, powder or fiber. The amount of yeasts and moulds was increased with the increasing addition of fiber in yogurts. The lowest amount of yeasts and moulds was in yogurt with the bamboo fiber. On the other hand the highest amount was in yogurt with chia flour
Utilization of pumpkin powder in baked rolls
Get PDFBakery products are good vehicles for dietary fiber incorporation. Traditionally, the source of dietary fiber has been mainly from cereals. However, vegetable can be used as potential source of dietary fiber. Pumpkin powder was characterized with good hydration properties (water holding and water retention capacity and swelling capacity), but fat absorption capacity was very low. Wheat flour was substituted with pumpkin powder at different level (2.5; 5; 7.5; and 10%). Addition of pumpkin powder modified the farinographic properties in various ways (water absorption and dough development time increased, while dough stability and mixing tolerance index decreased). Also it was concluded, that addition of pumpkin powder affected the qualitative properties of baked rolls. Enriched baked rolls had lower volume and specific volume. Moreover, the cambering values were significantly decreased as contain of pumpkin powder increased. The effect of incorporation of pumpkin powder in baked rolls on firmness values was also evaluated. It was also observed that enriched rolls were firmer during storage compared to control sample. Baked rolls containing pumpkin powder at higher addition levels had vegetable taste and flavour. From the results also concluded that the overall acceptance of baked rolls with 2.5 and 5% addition levels of pumpkin powder were comparable with control sample (without pumpkin powder)
Influence of composition of feed and lactation period on mineral composition of Mare's
Get PDFEffects of lactation period and feed on essential minerals composition of mare's milk were studied. Average Ca, P, Na and Mg concentrations in feed DM were 0.66, 4.30, 0.13 and 2.21 g.kg-1 of DM (dry matter), respectively. In regard to milk all elements concentrations were not similar to each other due to the changes of the lactation day differences. Average Ca, P, Na and Mg concentrations (in DM) caused by breed differences and lactation days were 1.95, 1.08, 0.53 and 0.22 g.kg-1, respectively. During the milk period, a high-quality feed were maintaining the major mineral composition of mare's milk in 1.5 - 2 times higher amount than milk of mare fed with pasture and a low-quality feed. The colostrum stage of mare was much shorter than other animals, the mare's milk on the 2nd day of lactation showed properties of initial milk in which its composition, particularly in minerals, were two times higher when compare to that on milk periods that was started from 5th day after parturition. It seemed that some factors, except well physiological conditions, such as mare's age, number of foaling, sex of foal etc. did not affect milk nutrient composition
The quality of ketchups from the Czech Republic's market in terms of their physico-chemical properties
Get PDFKetchup is a tomato-based condiment with a tang contributed by vinegar, sugar, salt and spices. Physical and chemical quality requirements for ketchup are regulated in the Czech Republic by Decree No. 157/2003 as amended. The main monitored parameters determining the quality of ketchups are total tomato content, total soluble solids, total organic acids and total salt content. In this work the following parameters were monitored in a total of eight ketchups from the commercial markets in the Czech Republic: pH, total solids, total soluble solids, citric acid content, acetic acid content, lycopene content, fructose, glucose and sucrose content and content of Ca, K, Mg and Na. In addition to chemical analyses, rheological measurements were performed and dynamic viscosity and yield stress were determined. The results obtained were statistically processed and the hypothesis i) whether the sales price of ketchups is related to the quality of ketchups expressed in chemical composition and ii) whether the chemical composition affects the rheological properties of ketchups has been verified. The Pearson correlation matrix showed very good correlation between the total solids and tomato content in the ketchup (R = 0.8464) as well as between the total soluble solids and tomato content in the ketchup (R = 0.8583). Another significant correlation was found between total soluble solids and total saccharides content in ketchup (R = 0.7309) as well as between potassium content and and tomato content in the ketchup (R = 0.8864). The chemical composition of ketchups did not significantly affect the dynamic viscosity of ketchups, however strong correlation between tomato content in ketchup and between yield stresses was found (R = 0.8436). No correlation was found between the ketchup price and chemical composition of ketchup, however cheaper ketchups contained more salt
Interaction of polyphenols and wine antioxidants with its sulfur dioxide preservative
Get PDFWine is considered to be a significant alcoholic beverage, which is the result of fermentation of grape must or mash. Wine is a must when the substances contained in it play a major role, which are essential inhibiting water, carbohydrates, acids, minerals, nitrates, polyphenols and aromatics. These biochemical components are an important tracking element in wine evaluation in terms of chemical analyzes. An important parameter of monitoring is polyphenolic substances. Polyphenol substances are identified in plant materials as several thousand pieces with a very diverse structure. However, they have a
common feature up to one or more aromatic rings substituted with hydroxyl groups. These substances may be present in plant material in a small or large amount. The total daily intake of polyphenols is estimated at 1 g. This is a higher intake than antioxidant vitamin intakes and it is confirmed that their antioxidant activity is higher than that of antioxidant vitamins. When monitoring the content of all polyphenols (TPC) in selected samples using a spectrophotometric method, a higher TPC content of red wines against white white wines can be observed. Total antioxidant activity is introduced to compare anti
oxidant effects of different mixtures and is based on the ability to eliminate radicals. Antioxidant activity and effects of polyphenols can be inhibited by the addition of preservatives to wine. The preservative is sulfur dioxide (SO 2), which has antimicrobial and antioxidant effects. This compound is not harmless because it is a strong allergen, blocks bacteria in the digestive tract and prevents the conversion of sugars and alcohol derivatives in the liver by blocking vitamin
B. In the normal life, SO2 is consumed under the E 220 mark. The aim of this work is to monitor the change in the total polyphenols content related to free and bound sulfur dioxide (SO2) content using accredited OIV-MA-AS323-O4B: R, 2009 samples in wine samples. Comparison of organic wines and wines produced by classical, it was found that organic wine have a higher content of biologically active substances and have a strong correlation factor TAA - total SO2 (r = 0.77 to 0.91), depending on the wine variety
Comparing the quality of honey from beekeepers and honey from the market chain
Get PDFHoney is a valuable food for its beneficial nutritional and dietetic effects. The quality of honey fluctuates considerably according to various criteria, the adulteration of honey with cheaper substitutes is not negligible. The quality of honey in the market chain with honey taken from beekeepers was compared in this study. A total of 10 samples from each group were tested for basic qualitative markers and compared with legislative criteria. The samples were analysed for fructose and glucose content, water content, titratable acidity and two tests for illegal sugar additions. The results revealed the addition of 25% of the technical syrup in one sample of honey from the market chain, one sample had the sum of fructose and glucose 56,3%, it is below the required limit 60% (differed by 6,3%). In other parameters the samples complied with the valid legislation. All tested parameters in honey from beekeepers met the criteria of the legislation, only 1 sample of blossom honey had the sum of fructose and glucose just below the required limit. The sum of fructose and glucose in this sample was 58.3 %, it differed by 2.9% from the required content of 60%. Sensory analysis was used to assess four samples of honey from beekeepers collected by different techniques. Results have not shown significant difference in sensory properties between manually pressed honey and honey obtained after whirling. The responses characterizing the favourable sensory properties of the examined honey samples were prevailing. The difference between the perception of honey after whirling and honey harvested by press manually was not demonstrated in sensory properties
Vicia villosa protein isolate: a new source of protein to make a biodegradable film
Get PDFEdible films from Vicia villosa protein isolate (VVPI) containing different contents of glycerol and sorbitol (30, 40, 50 and 60%w/w of protein) were developed. The aim of this study was to investigate the influence of type and concentration of plasticizers on the properties of edible films obtained from VVPI. Type and concentration of plasticizer significantly (p <0.05) affected the mechanical, barrier, thermal and surface properties as well as opacity of the films. As plasticizer concentration increased, tensile strength decreased concomitant with increase in elongation at break and water vapor permeability. The similar trend behavior was observed for the film solubility, which increased with increasing plasticizer concentration. Sorbitol plasticized films, showed higher film solubility compared to glycerol plasticized films. Sorbitol plasticized films provided the most tensile strength values; however, its effect on water vapor permeability was low. In contrast, glycerol plasticized films exhibited the least tensile strength values, resulting in increasing water vapor permeability. Opacity of glycerol plasticized films was lower than that of sorbitol plasticized films, and decreased with increasing plasticizer content (p <0.05). Also, a significant decrease (p <0.05) was observed in thermal features and surface hydrophobicity values with increasing in plasticizer contents. It was observed that the films plasticized with sorbitol had lower moisture content than those with glycerol
Is current system of direct payments suitable for farmers in Slovakia?
Get PDFCurrent system of direct payments in Slovakia can be described as per hectare payment. It is based on the logical assumption that the more land farmers cultivates, the more support they need. However, it seems like this principle works differently among EU member states. Historically, Slovakia is a country with the largest farms in EU 28. This extreme big physical farm size is here connected with the lowest output among EU 28 and simultaneously Slovak farms display also lowest efficiency. Paper examine generally accepted assumption that the more hectares farms utilize, the more subsidies they should receive, to help achieve more output. Research is based on the mutual pair combined correlation analysis, which examined relationship between utilized agricultural area, total output and total subsidies. Surprisingly just the relationship between total subsidies and total output was proved to be positive and in a moderate manner. Relation of total subsidies and utilised agricultural area, respectively total output and utilised agricultural area show the inverse relationship. In spite of the development in most European countries, Slovak outcomes indicates that the more subsidies farmers receive, the less output they achieve. This paradox can be caused by the actual Common Agricultural Policy system of subsidies remuneration which is not necessary suitable for whole EU 28 on the same level. 
Functional and thermal properties of flour obtained from submerged fermentation of durian (Durio zibethinus Murr.) Seed chips using Lactobacillus plantarum
Get PDFDurian (Durio zibethinus Murr.) is one of the most popular seasonal fruits in South East Asia, mainly Thailand, Indonesia, Malaysia and the Philippines. After consuming of the fruit pulp, the abundant durian seeds are usually disposed. However, they can be eaten after being boiled, roasted, baked, fried or cooked. Unfortunately, there is no sufficient information on the innovative utilizations of the durian seeds as raw materials in the preparation of modern foods. This study aims to characterize the functional and thermal properties of native and fermented durian seed flour obtained from submerged fermentation of durian seed chips using Lactobacillus plantarum, so that this information can be used as the basis in the development of functional foods. The effect of solid consistency (5 - 25% w/v), inoculum size (2.5 - 15% w/v) and time (0 - 40 h) on the swelling power, water solubility, water absorption capacity, oil absorption capacity, carbonyl and carboxyl content, degree of substitution and gelatinization temperature of the flour were investigated. Fermentation was found to alter all of the functional and thermal properties of durian seed flour. Although fermentation increased the gelatinization temperature and oil absorption capacity of durian seed flour, their value were still lower than that of wheat flour. Based on the carboxyl group content and degree of substitution, the fermented durian seed flour obtained from fermentation of durian seed chips at 15% w/v solid consistency and 5% v/v inoculums size for 24 h is safe for consumption. Fermented durian seed flour exhibits similar functional properties to that of wheat flour and offers its superiority and high potential applications in the food industry over wheat flour due to its high fiber content (8.50 ±0.26%), but low fat content (0.63 ±0.03%). However, rigorous research should be conducted to ensure the acceptability and practical implementation of fermented durian seed flour as raw material for the manufacture of bread, cookies, cake and noodle