Potravinarstvo Slovak Journal of Food Sciences
Not a member yet
1254 research outputs found
Sort by
The effect of the cooking method on rainbow trout (Oncorhynchus mykiss) fillets
Fish is nutritious seafood and contains protein with high biological value and essential nutrients for the human body. In Iran, the fish Oncorhynchus mykiss is locally known as Ghezelala and is a commercial fish species. Different methods were used to process the fish: boiling, frying in sunflower oil and grilling. This research investigated on effect of various cooking methods on proximate pH and cooking loss of fresh fish (Oncorhynchus mykiss). The highest and lowest values for protein were found in fish processed using grilling (18.51%) and frying (16.52%), respectively (p <0.05) compared to the fresh sample (18.20%). The fat content of the fried sample showed significantly highest (5.16%) (p <0.05), while the lowest fat content was found for the boiled sample (20.57%) compared to the fresh fat (24.36%) (p <0.05). Comparing the loss percentage of samples in different cooking methods showed that the boiled sample had the lowest value (25.46%) and the fried sample with the highest value (45.02%) (p <0.05). pH value in the boiled sample was the highest (6.74%), while the grilled sample had the lowest (6.63) compared to the fresh sample (6.54). The highest energy value was found for the fried sample (578.48 kcal/100g), and the lowest was for the boiled sample (269.29 kcal/100g). The results suggest that the boiled and grilled fish found higher nutritional quality due to the relatively high protein content, the most needed nutrients. The results also showed that all cooking methods did not significantly affect in mineral content of the fresh fish
A multiplicative approach to optimize the consumer properties of quick-frozen semifinished products from cultivated champignons
It is possible to maximise the consumer properties of grown fruit and vegetable products, significantly reduce their losses during the life cycle, and satisfy the public demand for products ready for consumption by using different preservation methods, particularly freezing. It has been found that the freezing of mushrooms without pretreatment does not provide a high-quality finished product. It justifies the expediency of mushroom pretreatment before freezing to stabilize their consumer properties. The inhibition effect of high temperatures on the oxidoreductase activity has been confirmed, ensuring the high preservation of cultivated champignons' natural color and consistency. A quasimetric assessment of the quality of quick-frozen cultivated mushrooms was performed, and the optimal heat treatment parameters were determined. Before freezing, blanched mushrooms' efficiency with polysaccharides has been scientifically proved. Rational concentrations and types of polysaccharides for mushroom processing have been determined. It has been established that blanching champignons in 0.1% citric acid solution followed by xanthan gum (0.2%), guar gum (0.1%), and lamidan (0.1%) processing ensure stability of consumer properties of quick-frozen semifinished products made of cultured champignons. After defrosting, they have an attractive appearance, natural light brown colour, elastic consistency, well-expressed mushroom flavour, and harmonious taste
Comparative characteristics of goat milk products in farms of Akmola and North Kazakhstan regions
Providing the population with high-quality products is a priority intention of the government. North Kazakhstan and Akmola regions are the most promising in developing the country's dairy cattle breeding and milk processing. An assessment of the qualitative indicators of milk production and processing in these areas would allow us to assess the dynamics of the development of the country's dairy industry and identify the main problems, so research on this issue is relevant. The study aimed to analyze the qualitative indicators of milk production and processing at the enterprises of the North Kazakhstan and Akmola regions, the factors affecting the quality of dairy products, and the prospects for expanding the range of enterprises. In the study, an InfraXact infrared analyzer was used to determine the quality of haylage in the diet of goats and for goat milk - the CombiFoss FT + analyzer. Generally, the quality of milk on the goat farms "Zeren" and "Tamasha-2050" in terms of fat, protein, lactose, fatty acid composition of milk fat, and somatic cells meets the regulatory requirements. The specificity of the goat farm "Tamasha-2050" is the production of various hard and soft cheese types. Farm "Zeren" is focused on the production scale and a wide range of products (drinking milk, yogurt, kefir, and ice cream). It was concluded that there is a wide choice for the consumer of high-quality dairy products from goat milk in enterprises
The effect of storage conditions on the microstructure of sterilized canned meat
The article presents the results of studies of changes in the microstructure of the meat system as a whole and its protein component during freezing, subsequent defrosting, and storage of canned meat. Microstructural analysis of the prototypes showed the presence of several types of destruction of muscle fibers, loosening of collagen fiber bundles, and the formation of multiple cavities due to the action of ice crystals. The main components of sterilized canned meat had new characteristics after thawing, such as decreased transverse striations of muscle tissue fibers, loosening of myofibrils, changes in the size and shape of sarcomeres, violation of sarcolemma integrity, and multiple fiber fragmentation with the formation of a fine-grained protein mass. Freezing did not lead to a decrease in the content of the high-molecular-weight protein fraction of the nitrogen system, the ratio of the peptide fraction content to the residual nitrogen remained equal to 5.2. However, the ratio of non-protein nitrogen to total nitrogen decreased by 1.8 times due to the destruction of low-molecular-weight nitrogen under the action of ice crystals. The dynamics of the eh values of control and experimental canned food samples during storage indicated the loss of oxidative stability of the protein system of the samples subjected to freezing. Based on the results, we would like to recommend that logistic organizations sort and confirm canned meat safety and quality requirements after thawing in the case of unforeseen circumstances
Use of laboratory equipment for analysis of external quality of food maize kernel
The purpose of this study was to investigate the influence of the parameters of the grain air-sieve cleaner in laboratory conditions on the external quality of food maize (Zea mays L.) kernel in terms of the design for the selection of a suitable sieve mesh for cleaning procedures. The object of the research was maize kernel, variety Pionier P0216, year of cultivation 2019. The available laboratory equipment was used in the study. To evaluate the external quality of food maize kernel, indicators were determined, which were investigated before and after cleaning. An Asus notebook computer with software from Microsoft Windows XP and Ofice 2010 was used to evaluate the measurement results. These results were achieved: an average bulk density of 846.77 kg.m-3 was found in the input sample of food maize kernel after harvest, admixtures before cleaning reached an average of 19.1% and impurities of 2.76%, cleanliness of kernels before cleaning averaged 76.9%, the output after cleaning expressed in terms of bulk density reached an average value of 851.15 kg.m-3, admixtures after cleaning reached 0.07% and impurities 4.21%, clean kernels after cleaning reached 94.86% and damage kernels after cleaning decreased slightly by separation of fragments and chipped kernels. In conclusion, it was stated that the laboratory technique for post-harvest treatment of grain is at a high level worldwide. Currently, the issue of post-harvest processing of grain in Slovakia is addressed at an average level. Post-harvest processing and storage of grain in terms of enginery and technological and economic aspects is little researched in the Slovak Republic, so these issues are open to further research
The yield of adipose tissue and by-products in the course of the slaughter of inbred and outbred bulls of the Ukrainian beef breed
The research focuses on analysing and generalising the distribution of internal adipose tissue and organs that are not part of the carcasses of inbred and outbred bulls of the Ukrainian beef breed. Animal stock inbreeding was determined based on five breeding records according to Wright’s method modified by Kyslovskyi. Two experimental groups of 5 bulls were formed. The average inbreeding coefficient for inbred bulls was 3.43%. Animals were bred up to 18 months of age. Following slaughter, the mass and the yield of the head, liver, lungs, heart, kidneys, and brain were determined, and 4 types of fat were separated and weighed: perirenal, from the stomach, intestines, and pericardial. Inbred animals are more prone to the accretion of internal adipose tissue. Inbred bulls have 1.8 points more of it. Fat is more intensely accumulated around inbred bulls' multichambered stomachs and kidneys. Intensive fat accumulation was observed around the hearts and intestines of outbred bulls. Adipose tissue around the heart and intestines is more variable in inbred and outbred animals – from the forestomach and kidneys. The weight of inbred bulls’ liver is less by 22.4%, kidneys – by 62.5%, heart – by 11.1%, and head – by 23.8% compared to outbred ones. The weight of their lungs is more by 10.5%. At the same time, inbred bulls tend to have brain weight gain of 12.5% and testicles – by 8.3%. Thus, inbreeding application in Ukrainian beef breeds with a small population size affects the growth of internal organs and the intensity of accumulation and distribution of interior fat. Due to more intensive accumulation of internal adipose tissue, inbred bulls have increased expenditure of forage energy for its formation. They are characterized by an increased yield of low-value raw fat, making them less efficient than outbred bulls for beef production.
The influence of grain mixtures on the quality and nutritional value of bread
The desire to survive in a competitive environment mobilizes managers to make unconventional decisions to increase their product range, quality, and safety. This study aims t to create a technology of bread with increased nutritional value using bioactivated cereal mixtures and develop new bread recipes. The experiment used bioactivated wheat and maize grains, flax, rye flour, 1st-graduate wheat flour, spontaneous fermentation starter, salt, and water. Vegetable components such as dried crushed hawthorn berries, jaggery, and barberry were also used. Standard, generally accepted chemical and organoleptic methods of examining raw materials, semi-finished and finished products were used. It was found that the best physical and chemical indices were possessed by testing the bread prepared with the addition of a 20% grain mixture. All experimental analyses improved several parameters compared to the control sample. The nutritional value of obtained products was increased from 0.5 to 3 times. According to the obtained results, it is possible to conclude the relevance of this topic is getting a new range of bread products with increased nutritional value
The effect of vibration massage on the salting process of ostrich meat
Existing massagers are characterized by relatively high energy consumption during operation, the metal consumption of the structure, complexity of the drive mechanism. Therefore, the search for effective implementation schemes of mixing operations and uniform structure formation of viscous and elastic-plastic raw materials, in particular, minced meat, subject to increased contact interaction while minimizing the force on the products, is relevant to the conducted research. The purpose of this work is to substantiate the technological preparation modes of the given minced meat with the use of a developed vibrating massager, as well as to determine the kinematic parameters of the oscillation system and graphic-analytical analysis of their change. The experimental model of the vibrating massager with an eccentric drive mechanism, a measuring evaluation base of rheological characteristics of the minced ostrich meat, and kinematic parameters of the vibrating drive of the massager, in particular, amplitude-frequency and speed characteristics were developed to carry out the specified tasks. High technological results were obtained when using the forced eccentric drive of the massager, which is characterized by a minimum mass of the oscillation masses of the parts compared to traditional unbalanced vibrators, which allow reducing 2 - 2.5 times the energy consumption to drive the vibrating massager under study. The practical value of the conducted work includes the use of the eccentric forced vibrating exciter for obtaining the force control over the minced meat to be formed, which reduces the oscillation masses of the drive and minimizes the energy consumption for the process, accordingly; it has the simplest structure among the mechanical vibrators, significantly reduces the dynamic loads on the supporting units of the vibrator as well as provides a sufficiently high contact interaction for both the vibration impact and the processing intensity in general
Antimicrobial susceptibility of mastitis pathogens of dairy cows in Ukraine
Mastitis is one of the most common diseases on dairy farms. It causes significant economic damage associated with the cost of treating sick cows, reduced milk yield and quality indicators of dairy products, and the risk of premature culling of animals. Treatment of cows with mastitis on dairy farms is carried out mainly with antimicrobial drugs, which are usually used without a preliminary test to identify the causative agent of the disease and determine its sensitivity to antimicrobial substances, which is an important part of the effectiveness of therapy. Increasing the resistance of bacteria to antimicrobial substances poses a threat not only to the animal but also to humans, as a consumer of dairy products. The availability of data on the sensitivity of mastitis pathogens to antimicrobial drugs makes it possible for veterinary doctors to choose the most effective antibiotic for treating animals with the shortest duration of treatment. The presented results of studies of breast secret samples taken from cows indicate that in 57.5% of cases, contagious pathogens of mastitis were identified. In particular, Streptococcus agalactiae made 24.1%, Staphylococcus aureus – 18.4%, Corynebacterium spp. – 7.2%, Streptococcus dysgalactiae– 5.6%, Streptococcus uberis – 2.2%. Environmental pathogens accounted for 42.5% of the total number of isolated isolates, among which Streptococci represented gram-positive microflora at 11.5 Streptococcuscus spp. (6.2% Streptococcuscus parauberis (4.4% Streptococcuscus Bovis (0.9%) and Staphylococcus spp. – 10.3%. Gram-negative microflora is 20.6%, among which the largest percentage belongs to E. coli – 8.4% and Klebsiella pneumonia – 1.9%. Mastitis caused by yeast accounted for 1.4% of all diagnosed pathogens. Antimicrobial sensitivity was evaluated using the disk diffusion method (Kirby-Bauer). According to the results of determining the sensitivity of mastitis pathogens to antimicrobial substances, it was found that the highest sensitivity of the isolated isolates was to Ceftiofur, Amoxicillin/clavulanic acid, Rifampicin, Amoxicillin, Gentamicin, Ampicillin, Bacitracin, Cephalexin, Cloxacillin, Enrofloxacin, Trimethoprim/sulfamethoxazole, Oxytetracycline, Lincomycin. The least sensitive – to Spiramycin, Tylosin, streptomycin, neomycin, Marbofloxacin, Tilmicosin, and Danofloxacin
Bromine in chicken eggs, feed, and water from different regions of Ukraine
The purpose of these studies was to analyse and compare the content of bromine in samples of chicken eggs, feed, and water from different regions of Ukraine in the dynamics of 2016 – 2020: with an increased risk of bromine in products (Kharkiv, Poltava, Dnipropetrovsk and Mykolaiv regions) and outside the risk zone (Volyn, Vinnytsia and Zaporizhzhia). Studies of bromine content in eggs, feed, and water were performed in the laboratory of toxicological monitoring of the National Scientific Center "Institute of Experimental and Clinical Veterinary Medicine" (Kharkiv) using X-ray fluorescence analysis. As a result of the conducted researches, the increase of the bromine content in chicken eggs in the dynamics of 2016 – 2020 was established: the bromine content increased regardless of the region of the poultry farm location. The highest bromine concentration in chicken eggs was found in Kharkiv, Dnipropetrovsk, Mykolaiv, and Zaporizhia regions. Bromine source in poultry products is the excessive intake of bromine in the poultry body with alimentary environmental factors (feed and water). Bromine content in feed for chickens increased in the research dynamics (from 35.1% in the Poltava region to 2.5 times in the Zaporizhzhia region). It exceeded the established EFSA (4.4% of the total) and the average in Ukraine (51.2% of the total number of samples). In addition, the average bromine content in feed from poultry farms of the studied regions of Ukraine correlated with the number of registered and approved bromine-containing pesticides. The average bromine concentration in water sources in the studied regions of Ukraine had no significant differences compared to the beginning of the study but exceeded the maximum allowable concentration by 21.7% in 2016, 34.8% in 2018 and 39.1% in 2020. The maximum bromine concentration was in water sources in Mykolayiv, Kharkiv, and Dnipropetrovsk regions