Potravinarstvo Slovak Journal of Food Sciences
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Survey of mycobiota on Slovakian wine grapes from Small Carpathians wine region
Get PDFA total of 13 samples of grapes (bunches) without apparent fungal contamination were analyzed. The samples were collected during the 2019 harvest from Vrbové village in the Small Carpathian region of Slovakia. For the isolation of fungi were used the direct plating technique on DRBC plates. The plates were incubated aerobically at 25 ±1 °C for one week in the dark. The data obtained from the cultivation of the grape berry samples revealed a high diversity of fungal species (a total of 1044 isolates were obtained). Alternaria and Rhizopus were the main components of the wine grape mycobiota of the Vrbovský subregion at harvest time (92%, each), followed by Cladosporium (85%), Penicillium (77%), Botrytis and Epicoccum (54%, each). The most abundant genera found by descending order were Penicillium (25%), Alternaria (24%), Cladosporium (20%), and Rhizopus (12%) and only in minor percentage by Aspergillus (3%) among others. The main fungal species isolated from genera Penicillium and Aspergillus were Penicillium expansum (57% RD) and A. section Nigri (97% RD). Of 17 analyzed Penicillium strains, 65% were able to produce at least one of the six mycotoxins analyzed in in vitro conditions by means of thin-layer chromatography method: citrinin, griseofulvin, patulin, cyclopiazonic acid, penitrem A, and roquefortin C
Differences between microbiota, phytochemical, antioxidant profile and dna fingerprinting of cabernet sauvignon grape from Slovakia and Macedonia
Get PDFThis study aimed to evaluate the microbiota, phytochemical, antioxidant profile and DNA fingerprinting of Cabernet Sauvignon grapes from Slovakia and R. North Macedonia. There were used two samples of grape berries (one sample from Slovakia and one from Macedonia). Each sample was analyzed in triplicate. The bacteria were cultivated on Plate count agar (PCA), microscopic filamentous fungi were cultivated on Malt extract agar (MEA). MALDI-TOF MS Biotyper mass spectrometry was used for the identification of microorganisms (bacteria and yeasts) and microscopic filamentous fungi with manuals. DPPH method was used to determine of antioxidant activity of grape berries. Phytochemical and antioxidant profiles were evaluated in grape berries samples. Total genomic DNA was extracted from mature grapes by GeneJET Plant Genomic DNA Purification Kit. The number of bacteria was higher in the sample of Macedonian grape (4.13 log CFU.g-1) in comparison to the grape from Slovakia as well as the number of yeasts was also higher in the Macedonian sample (2.57 log CFU.g-1). Antioxidant activity of Slovak grape berries was 0.55 mg TEAC.g-1 and of Macedonian grape, berries was 0.51 mg TEAC.g-1. Total polyphenol content was higher in grape from Slovakia (0.81 mg GAE.g-1) than in grape from Macedonia (0.77 mg GAE.g-1), while total flavonoid content was 0.57 and 0.17 mg QE.g-1 in Slovak grape and Macedonian grape, respectively. Total phenolic acid content was higher in the sample from Macedonia (0.40 mg CAE.g-1) compared to the grape from Slovakia (0.24 mg CAE.g-1). Total anthocyanin content was also higher in Macedonian grape (0.46 mg.g-1) compared to the Slovak sample (0.05 mg.g-1). The total polymorphism for all of the used primers of 87.5% was obtained for the Macedonian sample of Cabernet Sauvignon and 89.4% for the Slovak sample
Perception of sensory attributes and marketing tools of selected milk brands
Get PDFThe research has shown that in the last 5,000 years the human evolution has made the greatest leap in the human history. As a result of these changes, thanks to relatively recent discovery of a specific gene, even adult Europeans can digest milk. In their nutritional guidelines based on the scientific evidence, the official health organizations and institutions recommend drinking milk and eating low-fat dairy products such as yoghurts or cheese. The human body absorbs the necessary amount of calcium in the easiest form from cow's milk. Calcium is the essential element not only for healthy bones and teeth but it is also the important factor for the transmission of nerve impulses, it supports heart activity, helps reduce high blood pressure and "bad" LDL cholesterol levels and alleviate allergic reactions. It has impact on proper blood clotting, affects sperm mobility, helps prevent arthritis or can also contribute to better sleep. Milk is a valuable food not only for calcium content but also for selenium which slows down the aging process and contributes to the protection of the immune system. Acid dairy products prevent the digestive disorders, protect against gastrointestinal infections and improve skin condition. Despite all these positive aspects the consumption of milk, as well as dairy products, has the downward trend in Slovakia. In the last decade, the consumption was at a historical minimum and below the recommended annual dose, which is 91 liters of milk per person. Therefore, the main objective of this research paper was to examine the quality of milk produced by two selected competing companies and identify the various factors affecting consumers´ decision-making process when purchasing milk and dairy products. The attention was concentrated on the sensory attributes (colour, appearance, smell, taste and quality) and marketing tools (brand, packaging, label and price). The primary data were obtained by the questionnaire survey, which was conducted in the Slovak Republic with 284 respondents. For a deeper analysis, the data were evaluated by the statistical methods. Based on the results of the blind testing it was determined that even though the quality of monitored milk is the same, the respondents prefer the sensory attributes of Rajo semi-skimmed milk. When it comes to brand, packaging, label and price Tami semi-skimmed milk also lagged behind
Evaluation of storage methods of beef by microbiological and chemical indicators
Get PDFMeat and meat products are a major part of a person's ration. However, due to their high nutritional value, they are a favorable environment for the development of microorganisms and require refrigerated storage. The purpose of this work was to evaluate the storage methods for refrigerated and frozen beef by microbiological and chemical parameters and to suggest criteria for evaluating beef by the content of psychrotrophic microorganisms. It was found out that the storage of beef meat with an initial mesophilic bacterial content of about 4.88 log CFU.cm-2 of surface and psychrotrophic bacteria 3.79 log CFU.cm-2 at temperature 0 °C is only possible for 8 days, further, the microbiological indices exceed the acceptable standards. Investigation of the dynamics of microflora reproduction during the storage of beef in the frozen state at temperature -2 to -3 °C for 20 days established a decrease in 1.3 times the number of mesophilic bacteria in 10 days of storage. At the same time, the number of psychrotrophic microorganisms during this storage time was increased in 4.5 times, and 20 days in 7.9 times and amounted to 5.3 log CFU.cm-2 of surface area. This indicates that the storage of meat in the frozen state inhibits or completely stops the development of mesophilic microorganisms for 20 days. It was found out that storing of beef in the cooled state at a temperature of 0 ±0.5 °C for more than eight days is impractical, as its biochemical indices are worsening and signs of spoilage are appearing. At the same time, storing of beef in the frozen state at a temperature of -2 to -3 °C for 20 days does not cause such significant biochemical changes as in beef stored in the cooled state at a temperature of 0 ±0.5 °C for 16 days. Therefore, we have experimentally substantiated the quantitative indicators of the content of psychrotrophic microorganisms on the surface of beef intended for storage in a cooled or frozen state. The proposed microbiological criteria will improve the safety of beef
Methods for determining the botanical origin of honey
Get PDFThe demand for monofloral, original, and special (functional) kinds of honey, or those with geographical indication, is forecast. At the same time, there is a need to improve the methods for determining the botanical and geographical origin of honey. The purpose of the research was to select and apply a variety of techniques for identifying the botanical origin of honey for its correspondence to acacia species. Samples of honey from the Kyiv, Odesa, and Dnipro regions extracted in the spring and summer period were used in the research. Organoleptic, physicochemical, NMR spectrometry, and advanced melissopalynology methods were applied. The tests were carried out at the laboratories of the Department of Certification and Standardization of Agricultural Products, NULES, Ukraine; the Ukrainian Laboratory of Quality and Safety of Agricultural Products; and the Bruker BioSpin GmbH company (Germany). According to the research results, the requirements for acacia honey were met by the organoleptic method for samples B1 and B2; by the physicochemical method for A0 and A2; by NMR spectroscopy for not a single sample, all being assessed as polyfloral; and by pollen analysis for B1 and B2. The conducted studies confirm the need for a comprehensive approach to the identification of the botanical origin of honey for its conformity to acacia species. There is a need to review the physicochemical indicators for the compliance of honey with the acacia species obtained in Ukraine. After all, even the modern NMR spectrometry technique indicated that the specially fabricated sample that did not contain acacia pollen grains was acacia honey. Identification of the botanical origin of monofloral honey, in particular acacia, should be carried out in the following sequence: pollen analysis (by dominant pollen grains), safety (presence of antibiotics, pesticides), physicochemical parameters according to international requirements, organoleptic parameters
Determination of selected terpenic substances in grapes and wine of the cultivar Pálava
Get PDFThe presented study is focused on the determination of the content of terpenic substances in grapes and subsequently produced a wine of Czech variety Pálava (the Czech Republic, wine region Morava), which is a protected landscape with long-term tradition and culture. The aim of this study was the analysis of the aromatic profile of the cultivar Pálava, which was fermented by the original yeast strains from the Moravian wine region. Larger amounts of flavoring substances occur in grapes as bound flavoring substances, most often in the form of glycosides. One of the basic groups of aromatic substances is monoterpenes. The content of twelve free and bound terpenic substances was measured by the GC-MS method, namely linalool, ho-trineol, α-terpeniol, β-citronellol, nerol, geraniol, furan linalool oxide 1, furan linalool oxide 2, nerol oxide, epoxylinalol 1, epoxylinalol 2 and 2,6-dimethyl-3,7-octadiene-2,6-diol. The results were statistically compared by using a simple descriptive statistical method and ANOVA method. We noted a difference between the content of free and bound terpenes was very significant (p ≤0.05). We found that using uncommercial yeasts could have an effect on the content of the volatile and terpenic compounds in wines. An important finding was that in fresh berry extracts there was a higher proportion of bound terpenes than free terpenes. The results have shown that the production technology of wine and the fermentation process has a clear impact on the content of the substances
The use of consumer neuroscience in aroma marketing of a service company
Get PDFIn today's highly competitive era, it is becoming increasingly difficult for businesses to attract and keep customers. Modern marketing strategies focused on examining customer behavior, and possibilities of the business sector in influencing them are becoming increasingly beneficial. Consumer neuroscience has great potential here, as it reveals internal consumer preferences by using innovative techniques. Human senses play an important role in affecting these preferences, and smell has the greatest potential to influence customers subconsciously, and thus support the sale of products, keep customers in the store longer, or build a brand. Aroma marketing is the continuously developing field of consumer neuroscience. The paper aims to examine the use of consumer neuroscience in aroma marketing of a service company. After theoretical analysis, we carried out practical research aimed at examining the impact of aroma marketing in a selected service company – Sport Café in Nitra – to increase the sales of a particular product, and its real impact on the economic indicators of this company through the use of consumer neuroscience tools and questionnaire survey. In aromatization, choosing the right aroma is of the utmost importance, therefore in our research, this selection was done in the Laboratory of Consumer Studies at the Faculty of Economics and Management, SUA in Nitra. The research was carried out through conscious and unconscious testing of selected aromas by a randomly chosen sample of customers. Conscious testing included using a questionnaire method and unconscious testing was done using a face-reading device that provides an objective assessment of emotions based on facial expressions. The choice of aroma was followed by testing in real conditions, by diffusing the aroma in the café. Based on the collected data, we confirmed the positive impact of aromatization on coffee sales. In conclusion, we present some recommendations for service companies, focused mainly on cafés, with emphasis on the importance of aromatization for attracting and keeping customers and improving profitability
Influence of reduction on adhesive properties
Get PDFAn analytical analysis of the action of rolls on the medium and its behaviour at adhesion bonds with its surface are carried out. The methods and means of carrying out researches on determination of surface roughness are offered, and the experimental setting for determining the adhesion strength is developed. To reveal the essence and understanding of the general research execution, a number of hypotheses for the determination of adhesion are given and a generalized approach to the definition of adhesion is given. The physical nature of the influence of the roughness of the roller surface on the injection of the dies depends on the shape and angle of roughness, the application of mechanical forces, the degree of its previous dispersion (recipe) and its physical and mechanical properties. The nature of the contact interaction of the dough with the rough surface of the roller working organ in the injection nozzle of the fumigation machine is established. Violation of these mutual relations leads to the production of poor-quality products and a reduction in the efficiency of the machine. The contact area of the adhesive and the component forming work for overcoming the adhesion and deformation of the environment in determining the criteria influencing the process according to each particular period of the deformation stage are substantiated. The obtained data give an answer to a number of questions about the possibility of interaction of the surface of the working bodies from the environment. On the basis of their data, the actual change in the contact adhesion in the roller unit of the molding machine with a comparative analysis of existing ones with the newly designed design is considered. It is established that in order to provide a constant area of actual contact, which contributes to better adhesion, and, accordingly, the passage of a qualitative process of tightening, compression and pouring, the necessary condition is the consistency of the specified criteria. This means that the actual contact area , varies from to depending on the ratio of parameters
Research of quality indicators in protein-blueberry concentrates
Get PDFThe effect of blueberry coagulant in the form of specially processed blueberry paste on the building-up process of protein-blueberry concentrates has been considered in the article and the change in their physical-chemical indicators during storage has been determined. A study of blueberry coagulant application in the amount of up to 12% provides the effective running to process of thermo acid coagulation of milk proteins with a maximum clot yield (excluding limiting factors – organoleptic indicators and active acidity). It has been found that with an increase in the amount of blueberry paste adding from 2% to 10%, the yield of protein-blueberry concentrates increases from 5% to 40%, and the moisture mass fraction in clots decreases, on the contrary, from 73.4% to 67.1%. Other quality indicators of protein-blueberry concentrates were recorded: active acidity (from 5.0 pH at the beginning to 4.7 pH at the end of the storage life), and the water-retaining capacity at the level of (75.44 ±0.5%). Based on chromatographic studies, the degree of polyphenolic compounds transition (including anthocyanins) to protein-blueberry concentrates at the level of 52.26% has been determined by the calculation method and analyzed compared with control sample (blueberry paste) and colored whey. Based on the researches, protein-blueberry concentrates obtained by thermo acid coagulation of milk proteins are suggested to be used as basis in the cheese products recipes
Does foodservice industry care about CSR? A study in Portugal and Ukraine
Get PDFThe purpose of the article is to compare the CSR perception level of the food service industry in Portugal and Ukraine. The main goal of the study is to find the attitudes in Portugal and in Ukraine towards CSR. Additionally, two hypotheses were formulated to understand the possible relation between (1) the financial situation and (2) the duration of the company with the awareness level about the CSR concept. A quantitative approach, using questionnaires, was adopted to survey using a sample of 201 representatives of SMEs in the foodservice sector (101 Portuguese and 100 Ukrainian), in 2019. Descriptive statistics and Spearman test were used to analyze the data. The present work demonstrates a significant correlation between the financial situation of the company and the CSR awareness level of leadership. Furthermore, the research shows that activities related to the economic sphere and CSR workplace policy among food sector companies in Ukraine and Portugal are developed to a great extent. From this point of view, we can state, that the publication of the article is one of the results and supported by grant project KEGA 005SPU-4/2019 “Theory and Practice of the International Management and Entrepreneurship in Multicultural Environment”. In this study, two different countries were chosen (Portugal and Ukraine), which are different in culture, history, and economic background. The paper focused on the food service industry and contributes to the ongoing debate about the SMEs and its involvement with CSR. It also helps schools to identify plans in CSR policy and topics for future research