Potravinarstvo Slovak Journal of Food Sciences
Not a member yet
1254 research outputs found
Sort by
The state and the share of rural women on the agricultural entrepreneurship activities in the Slovak republic
Get PDFThe economic empowerment of rural women in the recent development of agriculture through entrepreneurship is considered an important challenge. Rural women often manage complex households and pursue multiple livelihood strategies. Their activities typically include cultivation of crops, farming animals, processing and preparing food, working for wages in agricultural or other rural enterprises, collecting fuel and water, engaging in trade and marketing, caring for family members, and maintaining their homes. The research aimed to collect up-to-date data on Slovak rural women dealing with business in the field of agriculture, women's role and status in society in rural areas, on the farm, women's participation in education, training, and agricultural services. The main focus is dedicated to their share on the management of agricultural entities, land cultivation, employment of rural women and men, and their deal on the selected entrepreneurial activities of Slovak agriculture. Women doing business in agriculture dispose of with considerable knowledge and experience in the agricultural and food sectors. The realized research showed that the scale of farms managed by women is 325 hectares. Rural women in the surveyed group are taking care of about 2.5% of the total area of agricultural land in Slovakia and they are employing 2.40% of the working forces in the agricultural sector in Slovakia. According to our survey, rural women are under-represented in managerial and ownership positions of agricultural entities.
Improvement of the sunflower oil stability by blending with moringa or sesame oils
Get PDFVegetable oils can be adjusted by different methods to enhance their commercial applications and to increase their pure quality nutrition. One of the most leisurely ways of creating new innovative products with desirable textured and oxidative properties is the mixing of vegetable fats/oils of various properties. Pure sunflower (SFO) blended with pure moringa (MOO) and sesame (SEO) oils in the ratio of 95:5 and 90:10 w/w. The outcomes showed that the highest acid value was observed at SFO + SEO 10% (0.782). Sunflower oil stabilized when blended with MOO and the levels of conjugated dienes (CD) and trienes (CT) were depressed compared to control. The TPC value was higher when the sunflower blended with moringa oil. The highest scavenging activity percentage was observed in SFO + MOO 5% and SFO + SEO 10% respectively. Meanwhile, the highest induction period at 100 °C was 11.45 hours in the treatment of SFO + MOO 5%. The master fatty acids in the sunflower and moringa oils are combined (SFO:MOO, 90:10), oleic, and palmitic acids. It seems from the current findings that suitable mixing of high linoleic oils with MOO will result in oil mixtures that can satisfy nutritional wants with expanded balance for home cooking and deep-frying
The influence of the denitrifying strain of Staphylococcus carnosus No. 5304 on the content of nitrates in the technology of yogurt production
Get PDFContamination of food with nitrates is a generally recognized problem. Milk is the basis for the production of many milk mixtures for baby food, and children are considered to be the most vulnerable category to the harmful influence of nitrates. The purpose of the search was to investigate the denitrification of milk with different amounts of nitrates by the denitrifying microorganisms of Staphylococcus carnosus in the technology of production of sour-milk products. The denitrification process of S. carnosus milk in the amount of 103 CFU.cm-3 was found to reduce the nitrate content by an average of 88.0 ±3.9 mg.kg-1 and in the samples of the first group was 10.3 ±2.4 mg.kg-1, the second 110.7 ±4.1 and the third 214.5 ±6.3 mg.kg-1, respectively. In the search of the denitrification process of S. carnosus milk in the amount of 104 CFU.cm-3, was found that in the ready yogurt in the samples of the first group the amount of nitrates was 1.1 ±0.1 mg.kg-1, in the second group 56.4 ±3.5 mg.kg-1, and in the third 159.5 ±4.1 mg.kg-1 respectively. In the search of the denitrification process of S. carnosus milk in the amount of 105 CFU.cm-3, was found that nitrates were practically absent in the samples of the first group, the second group did not exceed 10 mg.kg-1, and the third was 107.4 ±3.9 mg.kg-1. Therefore, received data indicate the possibility of using strain S. carnosus No. 5304 for denitrification of milk with a high content of nitrates in the technology of production of fermented milk products, in particular yogurt
The study on the process of dehydrating legumes during high-temperature micronization with infrared rays
Get PDFHeat treatment is a common operation in grain processing technology. Thermal action on grain is characterized by temperature level and duration. Also, the grain changes all its complex properties. Frequently, the temperature in grain activates the process of change in the moisture content and is accompanied by moisture loss. The processes of change in the heat and moisture are interrelated. Based on the experiments conducted on legumes (different varieties of bean, white lupin), a mathematical model of these processes has been developed and the appropriate non-linear differential equations have been used. The obtained equations cannot be solved either analytically or numerically, because some of the coefficients are unknown. The equations are solved based on certain assumptions. Based on these assumptions, the paper provides the calculation of the change in temperature and moisture content over time in legumes, such as bean and white lupin. The obtained results have been compared with experimental data
The carcass and meat quality characteristics of Japanese quail fed a diet supplemented with powdered Lactuca seriola leaves
Get PDFThe present study was aimed to evaluate the effect of dietary supplementation with Lactuca serriola leaves on growth performance, carcass characteristics, meat quality, and its antioxidant stability of Japanese quails. A total of eighty growing quails (1-week old) were distributed into 2 equal groups consisting of 40 birds (5 replicates of 8 birds each). The first group was fed a basal diet without Lactuca serriola leaves (0 g.kg-1 diet) and the second group received diets containing 20 g.kg-1 Lactuca serriola leaves. At age of 6 weeks, quails were slaughtered for meat and carcass examinations. The growth performance for the quails fed with Lactuca serriola leaves diet was similar to that of a control group. Carcass measurements, physical properties, and chemical composition of quail breast meat did not differ between the control and experimental group. However, the inclusion of Lactuca serriola leaves significantly increased the omega-3 polyunsaturated fatty acid content and improved breast meat lipid stability during postmortem refrigerated storage compared to the control diet. In conclusion, dietary supplementation of Lactuca serriola leaves can improve the performance of Japanese quail enrich its meat with an omega-3 polyunsaturated fatty acid, and reduce lipid oxidation during storage
Influence of eight chosen essential oils in the vapor phase on the growth of Rhizopus stolonifer and Rhizopus lyococcus
Get PDFThis study aimed to evaluate the fungicidal effect of eight essential oils against five strains of the genus Rhizopus. Strains were obtained from various moldy foods, namely Rhizopus stolonifer KMi 383 from chestnut, R. stolonifer KMi 510 from strawberry, R. stolonifer KMi 511 from nectarine, R. stolonifer KMi 524 from cherry tomatoes, and R. lyococcus KMi 512 from blackberry. The essential oils (EO) used in this study were jasmine EO (extract from Jasminum officinale L.), bergamot EO (Mentha aquatica L. var. citrata (Her.) Fresen), bitter orange EO (from Citrus aurantium L.), grapefruit EO (Citrus paradisi Macfady), sweet flag EO (East Asian Calamus, from Acorus calamus L. var. angustatus Bes), star anise EO (from Illicium verum J.D.Hook), geranium EO (from Pelargonium graveolens), and lemongrass EO (from Cymbopogon citratus DC). The semi-quantitative composition of the essential oil samples was determined by gas chromatography coupled with mass spectrometry (GC-MS). The antifungal activity of essential oils against the strains of R. stolonifer and R. lyococcus was determined during 7 days, using the micro-atmosphere method (0.625 μL.mL-1 of air). Two essential oils, geranium and lemongrass, completely inhibited the growth of all isolates. Bitter orange essential oil inhibited the growth of all isolates of Rhizopus stolonifer, but isolate of Rhizopus lyococcus began to grow after four days of cultivation. In conclusion, certain essential oils are highly effective in the vapor phase. These could be used in further tests of their antifungal activity and could be used in the control of Rhizopus spp. or other fungal pathogens
Evaluation of nutritional composition and sensory properties of cheese, cheese spreads and traditional butter from Slovak production
Get PDFCheese production is associated with the analysis of its nutritional composition as well as with the sensory evaluation of the acceptance of the products. The paper is aimed at the determination of basic chemical parameters such as the content of proteins, fat, dry matter, salt and, pH and also on the evaluation of sensory properties of hard cheeses by the sensory panel. The GC-MS analysis of cheeses, cheese spreads, and traditional butter was performed to evaluate the aroma profile of the dairy products analyzed. The dry matter in the analyzed cheeses varied between 56.75 and 71.83%, the fat content varied from 18.73 to 30.83%, and the salt from 1.21 to 2.61%. The presence of proteins was found between 27.76 and 32.61% and the pH of the cheeses ranged from 5.21 to 6.01. The results of the sensory analysis were processed using a PCA map. The results showed that sample no. 5 was rated within all attributes as the best. Sample 3, 2, and 1 followed. Sample 4 received the lowest score. The volatile aromatic compounds that contribute to a taste perception were analyzed by GC-MS in dairy products. The aroma profile was built by the volatile compounds that belonged to chemical families of alcohols, aldehydes, ketones, esters, amides, amines, imines, and terpenes. In particular, cheeses contained mostly alcohols (3-methyl-1-butanol), aldehydes (3-methylbutanal and benzaldehyde), and ketones (acetoin, 2,3,3-trimethylcyclobutanone, 2-heptanone, 2,3-butanedione, acetone, 2-butanone, 2-nonanone, 2- pentanone). The spreads most often contained alcohols (represented by 2-methyl-1-butanol, 3-methyl-1-butanol and cyclopropane-1,2,3-d3-methanol), aldehydes (2-methylbutanal, 3-methylbutanal, benzaldehyde) and ketones (acetoin, 2-heptanone, 2-pentanone, 2-butanone and 2,3-butanedione)
Characteristics of gelatin from skin and bone of snakehead (Channa striata) extracted with different temperature and time
Get PDFThis study aimed to determine the physicochemical properties of the skin and bone of snakehead fish as a potential source of gelatin through extraction at different temperatures and times compared to commercial gelatin. Extraction of skin and bones of wild snakehead fish (Channa striata) at different temperatures (50, 60, 70 ºC) and time (12,18, 24 hours). The pre-treatment process used a 0.1 M Ca (OH) 2 (1:6 w/v) immersion solution for 1 h and continued with 0.05 M citric acid (1:6 b/v) for 5 h. Before pre-treatment, the minerals of bones were degreased with 3% HCL solution for 24 hours. The results of the analysis showed that the differences in raw materials, temperature, and extraction time had a significant effect (p <0.05), as well as interactions among treatments (p <0.05) on the yield and gel strength. The yield of skin and bone tended to increase with extending extraction temperature and time, while the highest gelatin strength was found at 60 °C for 12 hours on the skin and 24 hours for the bone. The best gelatin was accomplished based on the highest performance of gel strength on skin and bones and compared to bovine commercial gelatin. The amino acids of the three types of gelatin showed higher levels of glycine and proline than other types of amino acids. Based on the total residues of each amino acid, skin gelatin and bone gelatin showed more dominant hydrophobic properties than hydrophilic properties, in contrast to bovine commercial gelatin. The three types of gelatin showed diverse chemical compositions, emulsion activity index, emulsion stability, water resistance, and fat binding capacity, which was reflected to be closely related to the source of the raw material and its amino acid content. The FTIR results showed that the extracted snakehead fish skin and bones have the potentiality to be used as gelatin equivalent to a commercial on
Satureja montana L. essential oil various dosages effect on the main rats’ biological features
Get PDFAn application of natural antioxidants remains the focus of research groups. The effect of Satureja montana L. essential oil in various doses on the main biological characteristics of Wistar rats was the main aim of the study. The intensification of protein metabolism in the blood plasma of rats on the background of the use of Satureja montana L. essential oil was noted. Total protein increases by 17.9 – 19.7%, and albumin by 27.6% in rats of the experimental group received the essential oil at a dose of 0.6 ml per kg of feed. A significant increase in the AST level in control group rats to 207.3 U.L-1 was revealed. Its one to a certain extent indicates the hepatoprotective effect of mountain savory oil and a decrease in inflammatory processes in the organs of the gastrointestinal tract in the conditions of cell maintenance of rats of the experimental groups. Gastric epithelium thickness of rats of both experimental groups was lower than the control animals. But it did not bear any signs of atrophy. The difference of this indicator in comparison with control was 12.75 μm (p ≤0.05) in the second group and it was reliable. The number of chief stomach cells increases in animals of the experimental groups, which may indicate a greater enzymatic activity. An increased dose of mountain savory oil contributes to the formation of more damage to hepatocytes on the periphery of the liver lobule. Thus, the relationship between liver enzymes and the state of peripheral hepatocytes was noted
The xanthine oxidase and its associated activities in the ovine milk and liver: distinctive in impact of in vivo molybdenum
Get PDFXanthine oxidase is molybdenum and iron-containing flavoprotein, catalyzing the final oxidation stage of purines and oxidative transformation of pterins and some aliphatic and aromatic aldehydes. Despite the importance of this enzyme, the distribution of xanthine oxidase in traditional household animal’s milk and tissues is unknown. Formerly, we have found most of the xanthine oxidase molecules in animal milk are inactive because of a lack of molybdenum. Ovine milk was processed by inserting in vivo molybdenum (tungsten) into drinking water. We gave opposite dates in the presence of tungsten too. Heating the milk of animals at 80 °C for 5 minutes in the presence of molybdenum and cysteine led to a sharp increase of xanthine oxidase and its associated – nitrate reductase and nitrite reductase activities. The change of xanthine oxidase and its associated activities were examined by spectrophotometry after treatment. It was established that metal ions added in drinking water for animals have an impact on enzyme activities. The activity is formed in the ovine liver even in the absence of exogenous molybdenum in drinking water. The associated activities of liver enzymes in the presence of molybdenum in drinking water had slightly increased. Tungsten-containing water led to the loss of all activities of liver xanthine oxidase. It is proposed that the liver contains a special protein involving in the incorporation of molybdenum (or tungsten) into xanthine oxidase molecule, however, the milk or mammary gland compounds lack this protein