Potravinarstvo Slovak Journal of Food Sciences
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Adaptation of two-dimensional electrophoresis for muscle tissue analysis
Get PDFIt is important to understand the molecular mechanisms that take place in muscle tissues and to predict meat quality characteristics. One of the most popular methods is two-dimensional electrophoresis, which allows us to visualize, share and identify different molecules, including meat proteins. However, the standard conditions of this method are not universal for all types of raw material, so the authors suggest a new variation of two-dimensional electrophoresis for muscle tissue analysis. Samples were tested by the classical version of isoelectric focusing (cathode buffer in the top and anode buffer in the bottom chamber of the electrophoresis cell) and its variation (anode buffer in the top and cathode buffer in the bottom chamber of the electrophoresis cell). Next, extruded gels were incubated in two different buffer systems: the first was equilibration buffer I (6 M urea, 20% w/v glycerol, 2% w/v SDS and 1% w/v Ditiothreitol in 375 mM Tris-HCl buffer, pH 8.8) followed by equilibration buffer II (6 M urea, 20% w/v glycerol, 2% w/v SDS and 4% w/v iodoacetamide in 375 mM Tris-HCl buffer pH 8.8 and the second, buffer А, consisting of 5 M urea, 2% w/v SDS, 5% v/v mercaptoethanol, 62.5 mM Tris-HCl buffer, pH 6.8 and 0.01% w/v bromophenol blue. Electrophoretic studies of muscle tissue revealed the best protein separation after changing the direction of the current (authors' variation), while no differences were detected after changing incubation buffers
Assessment of a new artificial buckwheat species Fagopyrum hybridum as a source of plant raw materials compared to F. Tataricum and F. Esculentum
Get PDFA promising way to increase the use of buckwheat is the wider introduction of technologies for its processing, including grinding of non-hulled grain. It requires the search for new plant materials with more suitable characteristics. In this work, the possibilities to use the grain of a new artificial buckwheat species Fagopyrum hybridum for flour production are studied in comparison with two cultivated species F. tataricum and F. esculentum. Some chemical characteristics of F. hybridum flour were evaluated. According to the size of the kernel fragments in different modes of milling within each species the significant differences were identified within F. esculentum and F. hybridum (p <0.001 and p <0.05, respectively); there were no significant differences within F. tataricum (p >0.1). Fragments of the seed hulls of F. tataricum and F. hybridum compared to ones of F. esculentum were distinguished by the absence of pronounced acute angles. For the cultivated species, amino acid compositions of grain protein of the studied samples manifest no strong deviations from earlier published results. The new species F. hybridum has the amino acid composition similar to ones of the both cultivated species with slight superiority in the content of all essential amino acids. So, the content of Cysteine, Tryptophan, Arginine, Lysine, Methionine, Leucine + Isoleucine, Threonine, Histidine and Valine in seeds of F. hybridum was 5.2, 15.0, 25.8, 30.2, 31.2, 36.0, 38.4, 41.1 and 46.2% higher compared to F. tataricum and 11.1, 43.7, 39.2, 3.7, 31.2, 15.2, 14.8, 20.0, 18.9% higher compared to F. esculentum. Using DPPH it was assessed the antioxidant activity (AOA) of whole grain flour of three buckwheat species and decreasing of the AOA during heating up to 100 °C. After water extraction the AOA was maximal for F. tataricum flour; F. hybridum and F. esculentum manifested similar values with the same decline dynamics during heating. After ethanol extraction the flour of F. hybridum shown higher AOA compared to both cultivated species before temperature treatment (1.3 times) as well as after heating to 100 °C (1.2 times). The results of the analysis of the fractional composition of flour from the whole grain of the three buckwheats shown the fragments of the seed hulls of F. tataricum and F. hybridum compared to ones of F. esculentum were characterized by the absence of pronounced acute angles. Additional experiments are needed to optimize the technology of whole-grain buckwheat flour. But the grain of F. tataricum and F. hybridum looks like more suitable for these purposes than the non-hulled grain of F. esculentum
Effects of meat and processed meat consumption on the lipid profile in the population with cardiovascular diseases
Get PDFMeat represents an important source of high-quality dietary protein for a large proportion of the global population. Also, red meat, in particular, significantly contributes to the intake of a wide range of micronutrients, including iron, zinc, selenium, vitamin D, and vitamin B12. Excessive consumption of meat and meat products is often associated with overconsumption of energy and fat, resulting in excess weight, obesity, and an increased risk of chronic diseases, such as cardiovascular disease and type 2 diabetes. This study aims to evaluate the relationship between meat and processed meat consumption frequencies and lipid profile in a group of 800 randomly selected patients hospitalized in the Cardiocentre Nitra. Patients were 20 – 101 years, (men, the average age was 61.13 ±10.47 years). The data necessary for the detection of dietary habits were obtained by a questionnaire method. Statistical comparisons between groups were made utilizing a one-way analysis of variance (one-way ANOVA) followed by Tukey's post hoc test. Our results show, that most respondents consume meat 1 – 2 times per week, while we did not notice a significant effect (p >0.05) of the type of meat on the lipid profile. The highest T-C, LDL-C, and TG values were seen in men who consume pork 3 – 4 times per week. Statistically significant was only the effect of pork meat on total cholesterol and triglycerides (p <0.05). In the consumption of beef and poultry, there was a non-significant effect on biochemical parameters of blood (p >0.05). We recorded a significant effect (p ˂0.05) of the consumption of frankfurters between consumption 1 – 2 times per week and 3 – 4 times per week. Up to 40.2% of respondents consume salami 3 – 4 times per week, and we recorded a significant effect on LDL levels between consumption 1 – 2 times per week and sometimes (p ˂0.05). Respondents who consume sausage, headcheese, and others products 1 – 2 times a week have non-significant higher T-C, LDL, TG, and lower HDL compared to less frequent consumption. High consumption of meat, mainly pork and processed meat seems to be associated with higher levels of total cholesterol, LDL cholesterol, and triglycerides
Sensory evaluation and acceptance of food made of edible insects
Get PDFThis paper discusses the sensory analysis of food enriched with selected edible insect species which are labelled as a novel food – house cricket (Acheta domesticus) and mealworm (Tenebrio molitor). Energy bars of two different compositions with the addition of cricket flour and puff pastry bars sprinkled with the whole roasted mealworm larvae were evaluated by consumer tests performed via a questionnaire survey. Respondents represented both men and women in equal numbers and included consumers with the experience of the sensory analysis and edible insects to ensure accurate results. Sensory analyses revealed that respondents associated their tastes with already known flavors (salty, sweet, bitter, fish, French fries, chicken, and mushrooms). The most common answer from respondents was a salty taste, followed by a sweet taste. There were also unusual comparisons such as pine seeds. Consumers’ positive attitude to these energy bars has been registered which shows that the Czech consumer accepts edible insects in a suitable form as a novel food and possible part of the food basket
Essential oils and their application in a food model
Get PDFThe aim of the study was to investigate the chemical composition, antioxidant, and antimicrobial activity of essential oils (Canarium luzonicum CLEO, Melaleuca leucadenron MLEO, Amyris balsamifera ABEO). There was Gas chromatographic-mass spectrometric analysis used for the characteristic of the semiquantitative composition of the essential oils. The DPPH method was used to determine the antioxidant activity. Minimum inhibitory concentrations (MIC) of essential oils against Stenotrophomonas maltophilia were analyzed in a 96-well plate. The broth microdilution method was used for the minimal inhibitory concentration. A gas-phase antimicrobial assay was used to determine inhibitory concentrations in a food model. CLEO proved to be the best with the lowest MIC 50 and 90 of 6.67 μL.mL-1 respectively 6.81 μL.mL-1 and antioxidant activity of 33.43% among the tested essential oils. The main volatile compounds CLEO were limonene 36.38%, elemol 16.65%, α-fellandren 12.18% and elemicin 9.59%. It showed inhibition of S. maltophilia growth in the food model at the lowest concentrations among the essential oils
Edible wild plants growing in adjacent spontaneous vegetation of energy plantations in southwest Slovakia
Get PDFThis paper evaluates the potential and perspectives of wild plant species and macrofungi from short rotation coppice. The research was conducted during the years 2014 - 2018 in stands of short rotation coppice willow and miscanthus grass in southwest of Slovakia. Evaluated wild plant species and macrofungi were divided into four groups (green vegetables, fruits and seeds, flowers and nectar, subterranean parts). The results showed that ground flora of short rotation coppice consisted of 74 edible species from 34 botanical families. Asteraceae, Rosaceae, Poaceae, Polygonaceae and Cichoriaceae families were represented the most. From the evaluated categories the most species belonged to the category with consumable aerial parts like leaves and shoots (59 species). The similar representation of species was found in the category of wild fruits and seeds consumed in the raw or preserved state and in category of edible subterranean parts (27 species and 22 species respectively). Principal component analysis showed that the edible parts with the strongest effect on the functional group differentiation were the fruits, seeds and subterranean parts
Mineral composition of Allium cepa L. leaves of southern subspecies
Get PDFThe mineral composition of Allium cepa L. leaves was measured by using the scanning electron microscope of Japanese company JEOL, model JSM600LA with EDS system. 11collection samples of FRC “All-Russian Institute of Plants Genetic Resources named after N. I. Vavilov” and 4 samples of FSBSI “Research Institute of Agriculture of the Crimea” were studied. 12 main elements (in mass., %) contained in onion leaves were evaluated. The samples with the maximum macro- and micronutrient elements accumulation in the leaves used for the sourthern subspecies breeds and hybrids selection were revealed. These samples can be used to prevent the elements deficiency in the human body. The following samples number with a high accumulation of the elements in the leaves was revealed: K – nine (from 20.0 to 3.3 max %: B12132B, trimontzium, Rouge pale, Red Wetherstfield, Blood red flat, Valensiya, Tavricheskiy, Yaltinskiy lux, Yaltinskiy rubin), P – five (from 1.8 to 2.8 mass., %:B12132B, Mestniy, Valensiya, Yaltinskiy lux, Yaltinskiy rubin), Mg – one (2.23 mass., %: Rouge pale), Ca – nine (from 5.4 to 8.3 mass., %: Mestniy, Rouge pale, Mestniy, Red Wetherstfield, Blood red flat, Valensiya, Brown Beauty, Yaltinskiy lux and Yaltinskiy rubin), Fe – two (from 0.5 to 0.8 mass., %: B12132B, Tavricheskiy), S – seven (from 2.2 to 2.5 mass., %: B12132B, Mestniy, Red Wetherstfield, Tavricheskiy, Yaltinskiy lux, Yaltinskiy rubin, Yaltinskiy model No. 3), Na – two (from 1.3 to 1.5 mass., %: B12132B, Mestniy), Cl – five (from 4.0 to 7.0 mass., %: Mestniy, B12132B, Trimontzium, Red Wetherstfield, Yaltinskiy model No. 3), Cu – one (1.9 mass., %: Yaltinskiy model No. 5), Mo – eight (from 5.2 to 7.0 mass., %: Tavricheskiy, Yaltinskiy lux, Yaltinskiy rubin, Yaltinskiy model No. 3, Mestniy, Trimontzium, Red Wetherstfield, and B12132B), Zn – seven (from 0.5 to 4.97 mass., %: Yaltinskii model No. 3, Mestniy, B12132B, Rouge pale, Blood red flat, Brown Beauty, Yaltinskiy rubin) and Si – one (0.5 mass.%,%: Yaltinskiy lux). The order of the elements accumulation variation in the onion samples was distributed as follows: Zn > Fe > Si > Na > P > Cl > Mo > Mg > S > Ca > Cu > K
Rational and irrational behavior of Slovak consumers in the private label market
Get PDFRational and irrational consumer behavior has already been the subject of several studies. Although their attention was mostly focused on traditional brands, these studies and their conclusions may also serve as a model for private label research, which is now increasingly coming to the forefront. Private labels are gradually becoming an adequate purchase alternative to traditional brands. The aim of the paper was to find out the influence of packaging and chosen marketing communication tools, on consumer purchasing decisions in the dairy segment. An anonymous questionnaire survey was chosen as the main research method, where participated 1,116 respondents from all over Slovakia; which was subsequently supplemented by the blind test involving 20 respondents under the age of up to 25 years. Seven chocolate-flavored yogurt samples were examined in the blind test; while the samples were such traditional brands by traditional producers as well as private labels. Interestingly, identical products were investigated - products from the traditional producer, both under its brand and under the retailer's private label. The results of our research proved some interesting findings - more than 28% of respondents buy private label products regularly and more than 53% buy them sporadically; whereas respondents do not buy private labels, mainly because of their lack of interest to try something new, assuming poor product quality and inadequate price; they buy them mainly because of lower prices compared to traditional product brands, comparable quality to traditional brands and good experience; respondents perceive private labels as good products of adequate quality and private labels evoke that products are adequate quality at a reasonable price. Although most respondents have no opinion on the packaging of private label products, more than 31% of them consider their packaging as unattractive and almost 36% think that their packaging does not affect them, but the results of the blind test partially refused this opinion
A randomised controlled trial of innovative specialised meat product for patients with cardiovascular and metabolic disorders
Get PDFCardiovascular diseases remain one of the leading causes of death globally. A lot of dietary patterns for CVD prevention have been proposed, but special attention is paid to functional foods. Bioactive proteins and peptides from animal sources are also considered tools for the prevention of CVDs. Here, 40 overweight or obese adult men and women aged between 61 and 66 years, with a body-mass index between 28 and 61 kg.m-2, were enrolled into a randomised controlled trial of new meat products for specialised nutrition. Participants in the control group (n = 20) consumed a standard hyponatric low-calorie diet for 28-30 days (10 days inpatient and 18-20 days outpatient), and in the experimental group – a low-calorie diet and 100g developed meat product (ratio of the porcine aorta to hearts 1:3) per day. Total cholesterol, triglyceride, cholesterol low-density lipoprotein, and cholesterol high-density lipoprotein levels were measured in the serum; from this, the atherogenic index was calculated. The positive effect of developed meat products on the serum lipid profile of patients during the trial was mild but noticeable. A significant reduction in cholesterol levels was noticed in the experimental group, by 18.2% and 14.0% after 7 – 10 and 28 – 30 days, respectively, while the cholesterol level in the control group returned to its original level after 28 – 30 days of dieting. The difference between the control and experimental groups was not significant, while data in the percentiles were. Therefore, it is more preferable to use a developed product as a component in diet therapy for hyperlipidaemic humans for over 28 – 30 days. Pronounced effects of the product could be linked to the unique proteome and peptidome of heart and aorta tissues based on organ-specific gene expression and the presence of tissue-specific substances
Estimation of phenolic compounds content and antioxidant activity of leaves extracts of some selected non-traditional plants
Get PDFThe aim of the research is the determination of the total antioxidant activity and the content of phenolic compounds of the leaves of 12 species of non-traditional plants, namely, Amelanchier alnifolia (Nutt.) Nutt. ex M. Roem., Aronia mitschurinii A.K. Skvortsov & Maitul., Castanea sativa Mill., Chaenomeles japonica (Thunb.) Lindl., Cornus mas L., Diospyros kaki L., Diospyros lotus L., Diospyros virginiana L., Lycium barbarum L., Lycium сhinense Mill., Pseudocydonia sinensis (Thouin) C.K. Schneid., Ziziphus jujuba Mill. Total phenolic content was evaluated using the Folin-Ciocalteu reagent assay. Antioxidant activity was measured using two different methods (DPPH – 2,2-diphenyl-1-picrylhydrazyl, MRAP – molybdenum reducing antioxidant power). Significant variability was observed in phenolic compounds content and total antioxidant activity. Total polyphenol content ranged from 38.02 (Z. jujuba) to 80.58 (C. sativa) mg GAE.g-1 DM, total flavonoid content from 22.47 (P. sinensis) to 54.61 (L. barbarum) mg QE.g-1 DM and phenolic acids content from 3.51 (A. mitschurinii) to 24.67 (Ch. japonica) mg CAE.g-1 DM. All tested samples exhibited DPPH• radical scavenging activities with values from 6.92 (A. mitschurinii) to 9.0 (C. mas) mg TEAC.g-1 DM. Antioxidant activity by molybdenum reducing antioxidant power method ranged from 109.43 (A. mitschurinii) to 322.95 (C. mas) mg TEAC.g-1 DM. Differences between the species of non-traditional plants were significant in all observed parameters. Obtained results of phytochemical composition demonstrated the possibility of leaves' use of non-traditional plants as sources of valuable bioactive compounds with health-promoting and disease-preventing properties