Potravinarstvo Slovak Journal of Food Sciences
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Mastitis pathogens and somatic cell count in ewes milk
Get PDFThe aim of this study was to determine the occurrence of pathogens in selected group of ewes and the relationship between somatic cell count (SCC) and the presence of pathogens. The experiment was carried out on a dairy farm, where predominantly breed was a Tsigai. Sampling was carried out in monthly intervals as part of the milk recording test day from February to July 2019. A total of 303 ewes were included in the survey, during the milk recording test day. The ewes with SCC ≥1000 × 103 cells.mL-1 were selected for further sampling at half udder level. Based on SCC the ewes were divided into five groups: <200 ×103; ≥200 <400 × 103; ≥400 <600 × 103; ≥600 <1000 × 103; ≥1000 × 103 cells.mL-1. The first group of SCC contained 33.9% of milk samples, the second 14.1% of samples, the third 5.7% of samples, the fourth 6.2% and the fifth 40.1% of samples. The most common pathogens were coagulase negative staphylococci (CNS). The most frequent CNS was Staphylococcus (S.) simulans (24.4%). S. aureus was identified in 5.3% of bacteriological positive samples. Almost 70% of ewes with bacteriological positive samples were repeated identified the presence of pathogens during tested period. SCC ≥500 × 103 cells.mL-1 were detected in 92.5% bacteriological positive milk samples. The presence of pathogens increased SCC in milk (p <0.001) as compared to samples free of pathogens. In conclusion, the SCC ≥500 × 103 cells.mL-1 could be important for detection of subclinical mastitis at half udder level in dairy ewes
Simultaneous determination of sweeteners and preservatives in beverages by HPLC-DAD-ELSD
Get PDFPeople suffering from diabetes or being overweight must severely reduce their sugar use, often seeking food with sweeteners. Often, sugar is replaced by non-nutritious sweeteners in beverages, which also contain several other substances like vitamins, caffeine, amino acids, phenolic compounds and thus increasing the shelf life of the beverages is additionally treated with the addition of preservatives. As the concentration of additives in food (including beverages) is determined by the legislation in force, it is necessary to have an appropriate analytical method for food control. Since artificial sweeteners and preservatives are very different substances, they are determined separately using different HPLC methods. In this work HPLC method combining the advantages of specific (diode array detector, DAD) and universal (evaporative light scattering detector, ELSD) detector was validated and used for simultaneous determination of benzoic acid, sorbic acid, aspartame, acesulfame K, saccharin, sucralose and steviol glycosides in sugar-free beverages. The proposed analytical method showed good linearity, precision, and accuracy. Measured limits of detection (0.6 – 11.8 mg.dm-3 depending on the analyte) were sufficient to analyze 5-times diluted beverage samples. The validated method has been successfully used for the simultaneous analysis of artificial sweeteners and preservatives in beverage samples (energy drinks, ice teas, carbonated drinks). Except for steviol glycosides, the concentration of monitored substances in beverages did not exceed the maximum permitted concentrations given in the valid legislation
Polyphenols and antioxidant activity in pseudocereals and their products
Get PDFPseudocereals are important as gluten-free crops that could be utilized as functional foods. They contain proteins with high biological value and also bioactive compounds such as phenolic compounds, flavonoids, vitamins, and minerals that can possess positive health effects on the body. Three types of pseudocereals (amaranth, buckwheat, and quinoa) were evaluated for polyphenols and antioxidant activity. Spectrophotometric methods were used for the determination of free phenols amount with Folin-Ciocalteu reagent, and total antioxidant capacity (TAC) with DPPH and ABTS reagents. Free phenols, the predominant part of polyphenols, were in pseudocereals in the range from 12.4 to 678.1 mg GAE.100g-1. The highest content of FP was found in buckwheat products (146.8 - 678.1 mg GAE.100g-1); quinoa and amaranth products reached much lower values (up to 226.1 mg GAE.100g-1). Antioxidant activity was in an agreement with the FP amounts order, the highest TAC values were again for buckwheat products (167.3 - 473.9 and 876.9 - 3524.8 mg TE.100g-1), followed by quinoa (78.2 - 100.6 and 738.9 - 984.5 mg TE.100g-1) and amaranth ones (25.0 - 69.7 and 118.2 - 431.4 mg TE.100g-1). A high positive correlation between FP amount and TAC values was evaluated for analyzed pseudocereals. The highest content of free phenols and the best antioxidant potential showed buckwheat wholemeal flour, so buckwheat could be characterized as a great source of free phenols with high antioxidant activity
Monitoring the stability of fortified cold-pressed sunflower oil under different storage conditions
Get PDFThe aim of the study was to evaluate the stability of cold-pressed sunflower oil mixed with different seeds and herb. The seeds and herb were added at 1% and 5% concentrations; samples were divided into 2 groups: stored in the dark and light. The primary products of oxidation and chlorophyll content were monitored during 3 months of storage. The results showed very low oxidation stability of experimentally produced cold-pressed oil mixtures/dressings, especially during storage on the light. The samples with 5% of hemp herb addition showed the best stability since they have peroxide value under 20 mekv O2.kg-1, both in the dark and on the light. Other samples, both stored in the dark and on light, were declared as not for human consumption due to high oxidative product development. The research represents an important storability evaluation of products that can be found on the market and that can be found very attractive for consumers
The effects of nutritional support on selected laboratory parameters in patients with colorectal cancer undergoing surgical resection of the colon.
Get PDFThe benefit of the nutritional support provided to patients with colorectal cancer who have undergone the planned resection of the colon in relation to the laboratory markers of nutrition was examined. And it is currently being discussed, that pre-operative optimization of nutritional status reduces the incidence of post-operative complications in cancer patients and regulates selected laboratory parameters. This was a retrospective study where the treatment group (n = 52) received the enteral nutritional support 21 days prior to the scheduled surgery and the other group was formed of patients without preoperative enteral nutrition (n = 52). Laboratory parameters (CRP, leukocytes, albumin, total proteins) were monitored for at least one month before the planned surgery and just before the operation, and the effect of supplemental enteral nutrition on selected laboratory parameters between these two groups was compared. In a group of patients with enteral nutrition, serum albumin levels increased significantly, while CRP was significantly reduced during preoperative enteral nutrition (albumin S-ALB from 35.42 to 37.48, p = 0.0008, C reactive protein from 26.5 to 14.092, p = 0.0007). Nutritional support 21 days prior to surgery in oncological patients resulted in an improvement in laboratory parameters compared to the group of patients without nutritional enteric support. Malnutrition in patients who are candidates for major surgical intervention is a risk factor for postoperative morbidity and mortality. However, further studies are required to verify the effectiveness of this early nutritional intervention on medium and long-term clinical parameters in different types of cancer
Research of selected physical indicators of table eggs in the small-scale breedings from the aspect of health safety
Get PDFThe purpose of this study was to investigate selected indicators of the table eggs in small-scale breedings, focusing mainly on the eggshell and its contamination and damage. Our object of study was eggs, shell, damage, and contamination of table eggs. Four small-scale breedings were randomly selected in Slovakia. These breeds were alternatively with an outdoor free-range. Laying hens Dominant was bred under conditions small-scale breeds No.1, No. 2 and No. 3 in the 1st laying cycle, and No. 4 in the 2nd laying cycle. Egg weight was balanced in three small-scale breedings. Egg weight was significantly higher in the fourth small-scale breeding, statistically significant (p <0.05) compared to egg weight in the studied 3 small-scale breedings. Shell weight and shell thickness in the equatorial plane of the egg were balanced in three small-scale breedings and in the fourth small-scale breedings were significantly higher, statistically significant (p <0.05). The higher egg weight per breeding is related to the higher laying hens age that was in the 2nd laying cycle compared to laying hens 3 small-scale breedings in the 1st laying cycle. Higher eggshell weight in three farms may be related to improved conditions in breeding hygiene, as confirmed by the results of investigations into contamination and damage to table eggs. These differences may also be related to nutrition
The NOVA system and ultra-processed foods in relation to consumer decision-making in foods choice
Get PDFThe purpose of the study was to investigate strawberry yogurt according to the NOVA food classification system. The object of research were strawberry yogurts from 6 different manufacturers, which are commonly available to food consumers, were randomly selected to investigate food samples under the NOVA food classification system. Based on this food, we present a methodology for assessing food safety with the application of the procedure. At the same time, we justify the classified food to Group 4, i.e. one of the 4 groups according to the NOVA system of food classification on a scientific basis, knowledge from the scientific literature. The evaluated results of the labeling of strawberry yogurt from various producers indicate that they are all classified as ultra-processed foods. Their characteristic feature is that they are industrial products with five or more, and usually many, items. Strawberry yogurt samples from various manufacturers evaluated contained 7 to 12 specific items that are not basic raw material, i.e. unprocessed or minimally processed food of Group 1
Dietary supplementation with magnesium citrate may improve pancreatic metabolic indices in an alloxan-induced diabetes rat model
Get PDFThe purpose of the current study was to evaluate the protective properties of dietary magnesium supplementation on pancreatic tissue of rats with alloxan-induced diabetes mellitus. Twenty-five male Wistar rats were split into five groups (control, diabetes, diabetes with 100 mg Mg daily, diabetes with 250 mg Mg daily, diabetes with 500 mg Mg daily) with feeding supplementation starting on day 1, diabetes induction on day 21, and animal sacrifice on day 30. Fasting glucose in blood serum was measured on days 21, 25, 27, and day 30. Glucose metabolism enzymes, namely, lactate dehydrogenase and glucose-6-phosphate dehydrogenase, were measured in pancreatic tissue upon the sacrifice, as well as lipid peroxidation, antioxidant system protective enzymes (catalase and superoxide dismutase), and glutathione system components (glutathione reductase, glutathione peroxidase, and glutathione reduced). Pearson correlation coefficients showed strong negative correlation between serum glucose (control and diabetic animals) and glucose metabolism enzymes, catalase, superoxide dismutase, glutathione peroxidase in pancreatic tissue (r >-0.9, p <0.05), moderate negative correlation with reduced glutathione (r = -0.79, p <0.05), moderate positive correlation with lipid peroxidation index (r = +0.67, p <0.05), weak correlation with glutathione reductase (r = -0.57, p <0.05). Magnesium supplementation slowed down diabetes onset considering fasting glucose levels in rats (p <0.05), as well as partially restored investigated dehydrogenase levels in the pancreas of rats comparing to diabetes group (p <0.05). The lipid peroxidation index varied between treatments showing the dose-dependent influence of Mg2+. Magnesium supplementation partially restored catalase and superoxide dismutase activities in pancreatic tissue, as well as glutathione peroxidase and reduced glutathione levels (p <0.05), while glutathione reductase levels remained unaffected (p >0.05). The obtained results suggested a model, where magnesium ions may have a possible protective effect on pancreatic tissue against the negative influence of alloxan inside β cells of the pancreas
Milk consumption in childhood and adulthood and its effect on body composition
Get PDFThroughout their life, people are exposed to many different types of milk. First, it is breast milk if infants are breastfed or special formula based on cow milk with modified composition if they are not breastfed. Later in life, it is recommended that humans consume the milk of other mammals as a source of highly valuable protein, calcium, and phosphorus. This work aimed to evaluate the effects of methods and duration of feeding in infancy and consumption of milk or milk alternatives in adulthood on body composition. We used a questionnaire of 21 specific questions to obtain information on breastfeeding and milk consumption. All 84 participants (18 men, 66 women; age 23.26 ±1.36) underwent measurement of body composition, using BIA methods (InBody 720). A comparison of the information from the questionnaire with the information from the body composition measurement was made. Significant differences were observed in visceral fat area (p = 0.048) and waist-to-hip ratio (p = 0.022) according to duration of breastfeeding. Participants who were fed formula for a shorter time than 1 year (until 12 months of age) showed a higher percentage of body fat (p = 0.047). The fat percentage of milk was a significant factor for the waist-to-hip ratio (p = 0.026). Participants consuming plant-based milk alternatives showed significant differences in waist-to-hip ratio (p = 0.031) and body mass index (p = 0.015) and highly significant differences in weight (p <0.001) and fat-free mass (p <0.001). In conclusion, results show that the duration of breastfeeding may prevent the development of overweight and eventually obesity. Usage of infant formulas as an alternative to breast milk should be limited to those who are unable to breastfeed. The current consumption of milk indicates the benefits of whole milk in the diet but also shows increasing interest in the advantages of plant-based milk
Nutritional and biological value of pork obtained from animals fed with lysine and methionine
Get PDFThe article presents material on the effect of the amino acids lysine and methionine in pig diets. Studies have been carried out to increase the live weight of animals, depending on the content of these amino acids in the diet when fattening up to 100 and 120 kg. Presented research results obtained during testing in certified and accredited laboratories. When growing gilts to live weight from 30 to 50 kg, a deficiency in the level of lysine was found, which reaches up to 29.6%, and methionine with cystine up to 23.1%. When growing animals from 81 to 120 kg of live weight, the lysine deficiency is 14.9%, and methionine with cystine is 8,8%. This necessitated balancing the diet of animals to the required level of amino acid content. The most effective on the growth and development of animals, as well as on indicators of pork quality, was the introduction of feed lysine in combination with methionine in pig diets