Potravinarstvo Slovak Journal of Food Sciences
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Engineering management of starter cultures in study of temperature of fermentation of sour-milk drink with apiproducts
Get PDFThe article considers the solution of problematic issues of engineering management of poly fermentation in the study of fermentation temperature of sour-milk drink with apiproducts. In the development of fermented dairy products, the components that are part of them, changes in their composition, and properties in the interconnection are considered as a technological system. The authors took into account that food technologies based on the use of the pure culture of one microorganism are limited by the capabilities of its fermentation system systems, the ultimate goal may not be achieved even by changing the conditions and parameters of cultivation. To successfully carry out fermentation processes in the technological system, a combination of cultures, associations of microorganisms with a wide range of fermentation products in contrast to one culture is promising to use. All experimental samples on a set of indicators prevailed control ones. The leader was a sample fermented with yeast with an equal ratio of cultures at a temperature of 38 – 40 °C. The authors found that the set of indicators of finished products for the production of sour-milk drinks with a complex of apiproducts, it is necessary to choose a three-strain poly fermentation product with a congruent ratio of cultures and set optimal fermentation regimes 39 ±1ºC for 5.0 ±0.3 hours
A case study comparing distillation technologies for plum palinka production
Get PDFPalinka production has a long tradition in Hungary and the neighboring countries. Previously, the fruit distillate was produced exclusively using the traditional Pot-Still Double Distillation (PSDD) technology. This distillation method means, in practice, a simple fractional distillation repeated twice. However, in other industries, such as the petroleum industry or the pharmaceutical industry, a continuous, so-called repeated distillation procedure is used (RCDS – Rectification Column Distillation Systems). In the production of palinka, the latter procedure has gained more and more ground in recent years, thus displacing the traditional technology. In the territory of today’s Hungary, there are more than 16,000 registered private palinka distillers. However, based on public databases, it is not possible to know the proportion of the two different palinka making processes used in palinka production. The two processes differ to a large degree. The amount of hearts obtained using the continuous operation plate rectification column (RCDS) is lower, while its alcohol content is very high: 75 – 90 vol%, depending on the fruit. On the other hand, when using the traditional pot-still double distillation (PSDD) method, the amount of hearts is higher, but its alcohol content is lower (60 – 70%). The continuous procedure, also called single-stage, is faster. This is one of the reasons for its popularity because it makes production more economical. The objective of our research was to find out whether a significant difference could be detected between the two plum palinkas produced using the two different distillation technologies, based on current legal requirements. Our research also included sensory testing to determine whether consumers could distinguish between the products manufactured in different ways. Our analyses were carried out in 2019 in the accredited laboratory of the National Food Chain Safety Office and among the students and staff of the Gödöllő campus of Szent István University
Investigating chemical changes during Snake fruit and Black tea Kombucha fermentation and the associated immunomodulatory activity in Salmonella typhi-infected mice
Get PDFThis study uncovered the chemical changes during kombucha's fermentation process and revealed the associated immunomodulatory activity in Salmonella typhi-infected mice. The snake fruit juice and black tea extract were processed into kombucha (a beverage known for its health benefits) by fermentation with SCOBY culture at room temperature for 14 days. Snake fruit kombucha showed high changes in fermentation parameters (total acidity, pH, and total sugar), as well as bioactive compounds and antioxidant activity. Salmonella typhi demonstrated a reduction in the population of CD8+TNFα+ and CD4+IFNγ+ of infected experimental animals. Both snake fruit kombucha and black tea kombucha have the potential to be utilized as an immunomodulator to circumvent unstable conditions of the immune system caused by Salmonella typhi. Black tea kombucha and snake fruit kombucha cancan raise the production of CD8+TNFα+ and CD4+IFNγ+ in mice infected with Salmonella typhi. In the group of normal mice, black tea and snake fruit kombucha were able to lower down the production of CD8+TNFα+, which is a potent mechanism to modulate the immune system. Further research is required to highlight the mechanism and role of black tea kombucha and snake fruit kombucha in the immune response that modulates and treats infection by Salmonella typhi
The occurrence of eleven elements in dairy cow´s milk, feed, and soil from three different regions of Slovakia
Get PDFThe objective of this study was to measure the concentrations of eleven essential, potentially toxic and toxic elements (arsenic – As, calcium – Ca, cadmium – Cd, copper – Cu, iron – Fe, mercury – Hg, magnesium – Mg, nickel – Ni, lead – Pb, selenium – Se, zinc- Zn) in raw cow’s milk (spring, summer, and autumn season), feed (spring and autumn season) and soil (spring season) from three different environments by routine methods in the certified testing laboratory. The samples were collected in the undisturbed region around Novoť, the moderately disturbed region around Tulčík, and the strongly disturbed region around Čečejovce. The concentrations of all toxic elements (As, Cd, Hg, Ni, Pb) and two essential elements (Cu, Se) in milk were under the limits of quantification (LOQ) from all investigated areas and during all seasons. Concentrations of other elements in milk from the undisturbed and disturbed areas were significantly different, generally with the highest levels in summer. In soil samples, the significantly highest concentrations of Ca, Cu, Ni were found in a strongly disturbed area, Mg and As in moderately disturbed area, and Fe, Se, Zn, Hg, and Pb in an undisturbed area. Cadmium was under the LOQ. In feed, the concentrations of essential elements, except of Se, were higher in the autumn. The significantly highest concentration of As, Ni were recorded in a moderately disturbed area and Pb in the undisturbed area in both seasons. Cadmium and Hg were under the LOQ. Despite the higher level of some elements in soil (Fe, Mg, Ca) from all regions, there were not elevated concentrations of any element in feed or milk. The concentrations of all toxic elements in milk were under the permitted limits. Thus, the milk from all investigated areas was not contaminated with the elements posing a health risk for consumers and it is considered safe for human consumption
Milk yield and somatic cells in dairy ewes with respect to their mutual relations
Get PDFThe objective of this study was to analyze milk yield and somatic cell count (SCC) expressed as somatic cell sore (SCS) in Lacaune dairy breed. Data from milk performance testing recorded between 2016 and 2018 (farm in West Slovakia) were used. A total, 377 individual milk yield and SCC records of 61 ewes (first, second and third lacation, respectively) were analysed. Mixed model for milk yield included fixed factors: SCC class (lowest, low, middle, high and highest), year of measurement, lactation number, month in milk and interaction between month in milk and SCC class, and random factors of ewe and error. Mixed model for SCS included milk yield class (lowest, low, middle, high, highest), year of measurement, lactation number, month in milk and interaction between month in milk and milk yield class. Random factors of ewe and error were considered as well. Milk yield was significantly affected ( p <0.05 or p <0.01) by all investigated factors. Except for interaction between month in milk and milk yield class, the remaining factors significantly affected (p <0.05 or p <0.01) also SCS. The analyses confirmed that SCC may be used as a useful indicator of udder health. It may help in identifying infected ewes, and thus, avoiding mammary infections to be spread throughout the whole flock
Occurrence of resistance to antibiotics therapy in coagulase-positive and coagulase-negative Staphylococci isolated from sheep´s milk in holding in Slovakia
Get PDFThe occurrence of bacteria Staphylococcus spp. was examined in a total of 3466 individuals and in 12 pool milk samples from 2017 to 2019. The experiment was carried out in two herds of the breed of sheep, Improved Valaska, in the Slovakia region. Eleven species of the genus Staphylococcus spp. (n = 431) were isolated and taxonomically identified. From the coagulase-positive staphylococci (CPS), S. aureus was isolated during the reporting period, however, most often in the third year (50). The incidence of S. intermedius and S. hyicus were irregular. The incidence of S. schleiferi was highest at the end of the follow-up duration. From the coagulase-negative staphylococci (CNS) (n = 158), were isolated S. epidermidis present in 20.4% (88) and S. chromogenes 11.4 % (49), S. caprae, S. xylosus, and other species rarely occurred. S. aureus (n = 133) showed maximum resistance to erythromycin 12.0%, novobiocin 10.5%, and neomycin 9.0%. The incidence of intermedial susceptibility was observed predominantly to a penicillin (16 strains), novobiocin (11 strains), erythromycin (14 strains), oxacillin, and cloxacillin (12 strains), neomycin (11 strains), and lincomycin (9 strains). Observantly, S. schleiferi (n = 101) showed the highest resistance to novobiocin (5.9%) and erythromycin (5.0%), however, a high incidence of intermediate susceptibility to erythromycin (9), amoxicillin, novobiocin (8), ampicillin, lincomycin (7), penicillin, methicilin and cefoperazone (5 strains) can be identified as adverse. The incidence of resistant and intermediate sensitive test strains S. aureus and S. schleiferi, especially for erythromycin, novobiocin, and neomycin, which are often used to treat udder inflammation in sheep, is relatively adverse
The effect of antioxidants on the quality of semi-finished minced rabbit meat
Get PDFUnder the current adverse environmental conditions, enrichment of the human diet with essential nutrients, including antioxidants, which exhibit immunostimulatory and adaptogenic properties and protect the body against the negative effects of free radicals, is extremely relevant. Their use in food production, including that of semi-finished meat products, improves the quality of such products and extends their shelf life. It is of scientific and practical interest to enrich rabbit meat with the antioxidant-containing plant raw materials and to study their influence on the quality parameters of semi-finished products. In this work, modern, standard, commonly accepted methods of research were used to fulfill the stated objectives. Statistical processing of the results obtained and evaluation of the reliability of the data was carried out by statistical methods using IBM SPSS Statistics for Windows. This study demonstrates the expediency of using grape-seed powder, green tea extract, and amaranth/flax flour in semi-finished rabbit meat products. The optimum component composition and amount of multiple supplements to add to the semi-finished product were determined. The total phenolic and flavonoid content and antioxidant characteristics of the test samples were studied. The highest antioxidant potential was observed in samples with flax-containing multiple supplements. This paper demonstrates that microbiological indicators in all samples throughout the storage period, in line with hygienic requirements, were lower than those in semi-finished products containing multiple supplements as compared with a reference sample, while organoleptic indicators of quality were more stable. The content of toxic elements indicates the sanitary reliability of semi-finished products. Determination of the acid number and peroxide number values during storage revealed high resistance of semi-finished products containing multiple supplements to the accumulation of free fatty acids and peroxide compounds. The obtained data indicate the effectiveness of using developed semi-finished products as antioxidant products in the diet of the population
Factors affecting raw milk quality of dairy cows under practical conditions
Get PDFUnder the practical conditions, it is important to evaluate the factors affecting milk performance. Data from test day yield and milk components should be useful for such evaluation. The aim of the experiment was to study the effect of season, udder health (by somatic cell counts SCC), parity, stage of lactation on milk production, milk components, and SCC under the practical conditions. Also, the frequency of incidence of high SCC during the season was observed. The experiment was realized on one dairy farm in dairy practice. The experiment lasted from December 2015 to October 2017. We examined 481 Holstein dairy cows (6910 milk samples). Milk samples were collected once per month – performed by recording test day. Only cows with 9 – 11 test days were evaluated. The effect of season, parity, stage of lactation, and SCC influenced most of the studied traits. The milk yield was highest at 2nd lactation. In the following lactations, the milk yields were decreasing. The SCC significantly increased with advanced parity. The elevated SCC was found in the beginning and in the final part of lactation. SCC as a factor significantly reduced milk yield, lactose content but increased fat and protein content. In conclusion, under practical conditions, the management should use the data from test days and analyze them for a better understanding of the performance efficiency at the farm level and for implementing more sophisticated decision making in farming
Impact of humic acid as an organic additive on the milk parameters and occurrence of mastitis in dairy cows
Get PDFGiven growing concerns about the use of antibiotics in the treatment of animals, identifying organic alternatives as feed additives to improve animal health and the development of immune responses has become of interest in dairy farming. Humic acids (HA) seem to be a suitable alternative with a favorable impact on the health and production parameters of animals. This study aimed to determine the effects of an HA supplemented diet on milk parameters as well as the effects on somatic cell count (SCC) and the occurrence of mastitis in dairy cows during the peripartum period. Twenty dairy cows in the last stage of pregnancy were selected from a herd of 140 cows. The selected cows were randomly divided into two groups: control (C) and experimental (E). The two groups were fed the same feed mixture and group E was additionally supplemented with HA at a total dose of 100 g per cow per day during the last 50 days of pregnancy. The milk parameters (dry matter, lactose, fat, crude protein, casein and milk urea) and SCC of every cow, and the presence of mastitis, were checked on days 10 and 30 during the first month of lactation. The results of the study show that dietary supplementation with HA significantly reduced the milk urea (MU) content and SCC on the 10th day after calving but did not affect the other milk compositions. In addition to the decreased MU and SCC, the number of positive quarters detected by the California Mastitis Test was reduced by 20.0% and the occurrence of mastitis caused by coagulase-negative staphylococci (CNS). Based on the obtained results we can conclude that the addition of HA stabilizes the nutrient digestion, as was confirmed by a reduced MU content in the supplemented group. Their indirect beneficial effects improved the development of immune responses, resulting in decreased SCC and the occurrence of mastitis caused by CNS
Effect of commercial yogurt starter cultures on fermentation process, texture and sensoric parameters of white yogurt
Get PDFIn this work, we have compared and described the fermentation process of two commercial yogurt starter cultures during the white yogurt production. We used freeze-dried thermophilic starter culture YoFlex® YF - L812 and deep-frozen starter culture Delvo® Fresh YS – 241 for the production of white yogurts. We analysed titration acidity, active acidity, total viable counts, texture, and sensory parameters of white yogurts produced in laboratory conditions. This research was performed for dairy company Mliekareň Kopanice Selce, s.r.o., Slovakia. We did not found statistically significant differences (p >0.05) in titration acidity of both yogurts after 7 hours of fermentation. We did not found statistically significant differences (p >0.05) in the pH of both yogurts after 7 hours of fermentation. We found statistically significant differences (p <0.05) in all textural parameters (hardness, consistency, cohesion, and viscosity). The total viable count of microorganisms in yogurts after 24 hours of fermentation was 6.28 x 107 and 7.14 x 107 respectively