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The aim of the study was to determine the efficacy of acidified sodium chlorite (ASC), chlorine dioxide and trisodium phosphate (TSP) in the reduction of contamination levels regarding total microbial count, coliform bacteria, Staphylococcus aureus and Salmonella Enteritidis in chicken carcasses after a decontamination process. Experimental material comprised skin sections from the neck collected from chickens on the production line. Each sample consisted of skin sections coming from three carcasses, each at approx. 20 g. Next each section was divided into two parts, one being the control and the other was the tested sample. Samples were decontaminated by immersion in solutions of analyzed antimicrobial compounds. Control samples and samples after decontamination were subjected to microbiological analysis in which total microbial count, coliform bacteria and Staphylococcus aureus were determined in accordance with the standards PN-EN ISO 4833:2004, PN-ISO 4831:1998, PN-EN-ISO 6888-1:2001 and PN-EN-ISO 6888-1:2001/A:2004, while Salmonella Enteritidis was determined according to the recommendations of the manufacturer of the Chromagar Salmonella Plus medium. An effective antibacterial effect of the applied compounds was found in the limitation of bacterial counts on chicken carcasses. The greatest reduction of total bacterial count, amounting to approx. 25%, was shown when applying acidified sodium chlorite. Trisodium phosphate was the most effective agent against coliform bacteria, reducing their number by 92%. The best antibacterial effect in relation to Staphylococcus aureus was obtained using chlorine dioxide. A 44% reduction of the count of Salmonella Enteritidis was observed for all the applied compounds. A considerable decrease in the level of microbial contamination in poultry carcasses, including pathogens, effectively enhances the standard of health safety in poultry meat.
Among regional Polish dairy products, such as redykołka, bundz, and bryndza cheeses, the most popular one is oscypek cheese. Oscypek is a cheese produced in over a dozen districts of the mountainous Podhale region. It is obtained from raw sheep milk or a blend of sheep and cow milk mixed in appropriate proportions. Oscypek is a pasta filata type of cheese, smoked or unsmoked. The aim of the research was to evaluate the microbiological quality of oscypek cheeses produced in the Podhale region. In total, 32 samples of cheeses were examined: 16 samples of smoked cheeses and 16 samples unsmoked. The following parameters were measured: total bacteria count (TBC), most probable number (MPN × g⁻¹) of coliform bacteria and Escherichia coli, MPN of Clostridium perfringens, and counts of yeasts and moulds. Coliform bacteria and E. coli, the microorganisms used as indicators of manufacturing hygiene, were present in all samples. The MPN of coliforms exceeded 10² per 1 g in 81% of the smoked oscypek cheese samples and in 88% of the unsmoked ones. C. perfringens spores were present in 19% of all samples, but their MPN × g⁻¹ did not exceed 10. The presence of moulds and yeasts was established in 63% and 100% of the cheese samples, respectively. Moulds and yeasts were present in the amounts of 10-10³ and 10²-10⁵ cfu/g, respectively, in the smoked cheeses, and in the amounts of 10-10⁴ and 10³-10⁵ cfu/g, respectively, in the unsmoked cheeses. The presence of coliforms in all the oscypek samples examined indicates deficiencies in production hygiene. This was also confirmed by the considerable percentage of cheese samples contaminated with moulds and yeasts. However, the number of these microorganisms was comparable with their presence in similar cheeses produced industrially from raw sheep milk or pasteurized cow milk. In the case of oscypek cheeses, the process of smoking may lower the TBC and the number of moulds and yeasts by approx. 1 log row compared with unsmoked oscypek cheeses. However, cheese smoking does not reduce the number of coliforms, E. coli and C. perfringens.
Цель работы состояла в сравнении результатов, полученных с применением теста „Lactocult”, с результатами, полученными при помощи микробиологических методов, обязывающих в настоящее время. Исследования провели на 50 пробах молочного сырья, определяя общее число кислородных микроорганизмов, титр и число палочек из группы ободочной кишки, а также число оксидаза-положительных микроорганизмов. Тест „Lactocult”, из-за простоты применения и значительного сокращения времени исследований кажется особенно пригодным в случае микробиологических рутиновых исследований, целью которых было бы обнаружение, не превысило ли число исследуемых бактерий уровня, определенного требованиями. Сравнивая полученные результаты при помощи тесте t-Стъюдента, получили следующие коэффициенты корреляции: для общего числа кислородных микроорганизмов — 0,769, в случае палочек из группы ободочной кишки — 0,822, а также в случае оксидазо-положительных микроорганизмов — 0,574. Полученные результаты статистически существенны.
Przeprowadzono ocenę skuteczności oczyszczania ścieków z zakładu mięsnego na podstawie określania ogólnej liczby drobnoustrojów oraz pałeczek E. coli, Salmonella i paciorkowców grupy D w ścieku surowym i oczyszczonym. Badania wykazały, iż skuteczność oczyszczalni mechaniczno-chemicznej pod względem usuwania zanieczyszczeń mikrobiologicznych jest niewielka. Liczba badanych bakterii tylko nieznacznie obniżała się po oczyszczeniu, bez względu na porę roku. Szczególnie niepokojący był fakt częstego wykrywania w oczyszczonym ścieku pałeczek Salmonella. Przeprowadzone badania wskazują na konieczność poddania ścieków z zakładów mięsnych dalszemu oczyszczaniu metodami biologicznymi.
The influence of low frequency (40 kHz) and medium intensity (2 W·cm⁻²) ultrasound on the total number of bacteria and Salmonella on the skin of chicken broilers before chilling was investigated. Chicken wings were used for the study. The first part of raw wings was used for total number of bacteria investigation. The second part was contaminated with Salmonella. The changes of total number of bacteria (OLD) and number of Salmonella (SALM) after sonication were determined. Ultrasound treatment was conducted in distilled water (AQ) or 1% lactic acid aqueous solution (LA) at 20°C. The sonication time of a sample was 1, 3 or 6 minutes. The sonicated samples were compared with parallel, untreated samples. The obtained results show that OLD on wings’ skin decreased more than 1.8 log after 6 min of sonication in AQ and SALM decreased 3.6 log in LA. The effect was caused by the ultrasonic cavitation and microflows in the ultrasonic field. The phenomena removed the bacteria from the skin and passed it to the solution and become inactivated. It was concluded that the sonication effect was amplified by the LA. It was supposed that LA stimulates sonobiological phenomena in cell membranes and, in effect, decreases its vital functions and causes the death of bacteria. The cleanness of chicken carcass’ (wing) skin was increasing with the longer duration of sonication. But it was supposed at the same time that the temperature of the liquid (AQ, LA) in the ultrasonic field increases directly in proportion to the time of exposure, 4.5°C in 6 min. The low frequency and medium intensity ultrasound decreases the microbial load on carcass skin, especially the Salmonella, while treated in aqueous lactic acid solution. Sonication should be conducted before the chilling of the carcass. The utilization possibility of chicken carcass decontamination ultrasonic method is confirmed.
The present study was undertaken to examine the effects of immunostimulation with isoprinozine (Isoprivet) on the hygienic quality of milk and the health status of mammary glands. Eight HF cows with mastitis whose milk did not meet the extra- class requirements were involved. The following examinations were performed: clinical examination of the udder, macroscopic assessment of milk secretions, FCR, milk cultures, quantitative determination of microorganisms and somatic cell count. No other preparations were used during the experiment. The preliminary results show that isoprinozine has beneficial therapeutic and prophylactic effects on dairy cows already affected or at risk of mastitis. Moreover, it markedly improves the parameters of hygienic assess- ment of raw milk whose quality is maintained within acceptable standards. The findings suggest that isoprinozine may be used as a stimulator of non-specific mechanisms of immune response during lactation in cows.
The purpose of the study was to determine the effects of the interaction between methods of udder and teat cleaning before milking, the sequence of fore-stripping relative to udder and teat cleaning, and post-milking teat disinfection on somatic cell count and total microorganism count in bulk tank milk. The study was carried out in 2004 on 160 dairy farms (average 19.4 cows per herd), located in neighboring parts of the Mazowsze and Warmia and Mazury regions. It was found that the optimal combination of pre- and post-milking procedures is: fore-stripping, then pre-milking udder and teat wiping with a towel soaked with a disinfectant, and post-milking teat disinfection. However, in very dirty cows the most favorable combination is washing with water containing a disinfectant, followed by fore-stripping. In this case post-milking teat disinfection should not be employed, for the joint effect of this procedure and the specified method of pre-milking udder cleansing is negative in cold months (January-March and September-December), with no effect in other months.
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