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1

Wlasciwosci przeciwbakteryjne heksanowego i wodnego ekstraktu chrzanu w stosunku do paleczek Salmonella

100%
Szczawinska M. E., Czapska A., Szczawinski J., Jackowska-Tracz A.
Acta Scientiarum Polonorum. Medicina Veterinaria
|
2008
|
tom 07
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nr 3
65-73
2

Wplyw wysokiego cisnienia hydrostatycznego na wlasciwosci organoleptyczne ryb wedzonych

100%
Peconek J., Szczawinska M. E., Szczawinski J., Fonberg-Broczek M.
Acta Scientiarum Polonorum. Medicina Veterinaria
|
2008
|
tom 07
|
nr 4
57-61
3

Parameters of growth curves of Salmonella Enteritidis subjected to conventional heat or microwave treatment

100%
Szczawinski J., Klusek A., Szczawinska M. E.
Bulletin of the Veterinary Institute in Puławy
|
2009
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tom 53
|
nr 4
Salmonella Enteritidis culture was subjected to heat or microwave treatment to obtain bacteria reduction by 4, 5, and 6 log units. Control, heated and microwaving micro-organisms were incubated in a nutrient broth at 10°C for 432 h. Growth-curve parameters were calculated using Gompertz and Baranyi equations. It was found that in most cases untreated salmonellae had a shorter generation time, a higher exponential growth rate, and a higher maximum growth rate than heated and microwaving bacteria. Growth of bacteria subjected to microwave treatment was more dynamic than that of bacteria subjected to conventional heating. It was expressed by statistically-significant differences in generation time and exponential growth rate calculated by the Gompertz equation, as well as maximum growth rate calculated by the Baranyi model for both compared groups of salmonellae.
4
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Modeling the effect of temperature on survival rate of Listeria monocytogenes in yogurt

100%
Szczawinski J., Szczawinska M. E., Lobacz A., Jackowska-Tracz A.
Polish Journal of Veterinary Sciences
|
2016
|
tom 19
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nr 2
The aim of the study was to (i) evaluate the behavior of Listeria monocytogenes in a commercially produced yogurt, (ii) determine the survival/inactivation rates of L. monocytogenes during cold storage of yogurt and (iii) to generate primary and secondary mathematical models to predict the behavior of these bacteria during storage at different temperatures. The samples of yogurt were inoculated with the mixture of three L. monocytogenes strains and stored at 3, 6, 9, 12 and 15°C for 16 days. The number of listeriae was determined after 0, 1, 2, 3, 5, 7, 9, 12, 14 and 16 days of storage. From each sample a series of decimal dilutions were prepared and plated onto ALOA agar (agar for Listeria according to Ottaviani and Agosti). It was found that applied temperature and storage time significantly influenced the survival rate of listeriae (p<0.01). The number of L. monocytogenes in all the samples decreased linearly with storage time. The slowest decrease in the number of the bacteria was found in the samples stored at 6°C (D-10 value = 243.9 h), whereas the highest reduction in the number of the bacteria was observed in the samples stored at 15°C (D-10 value = 87.0 h). The number of L. monocytogenes was correlated with the pH value of the samples (p<0.01). The natural logarithm of the mean survival/inactivation rates of L. monocytogenes calculated from the primary model was fitted to two secondary models, namely linear and polynomial. Mathematical equations obtained from both secondary models can be applied as a tool for the prediction of the survival/inactivation rate of L. monocytogenes in yogurt stored under temperature range from 3 to 15°C, however, the polynomial model gave a better fit to the experimental data.
5
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Modeling the effect of temperature on survival rate of Salmonella Enteritidis in yogurt

100%
Szczawinski J., Szczawinska M. E., Lobacz A., Jackowska-Tracz A.
Polish Journal of Veterinary Sciences
|
2014
|
tom 17
|
nr 3
The aim of the study was to determine the inactivation rates of Salmonella Enteritidis in commercially produced yogurt and to generate primary and secondary mathematical models to predict the behaviour of these bacteria during storage at different temperatures. The samples were inoculated with the mixture of three S. Enteritidis strains and stored at 5℃, 10℃, 15℃, 20℃ and 25℃ for 24 h. The number of salmonellae was determined every two hours. It was found that the number of bacteria decreased linearly with storage time in all samples. Storage temperature and pH of yogurt significantly influenced survival rate of S. Enteritidis (p < 0.05). In samples kept at 5℃ the number of salmonellae decreased at the lowest rate, whereas at 25°C the reduction in number of bacteria was the most dynamic. The natural logarithm of mean inactivation rates of Salmonella calculated from primary model was fitted to two secondary models: linear and polynomial. Equations obtained from both secondary models can be applied as a tool for prediction of inactivation rate of Salmonella in yogurt stored under temperature range from 5 to 25°C; however, polynomial model gave the better fit to the experimental data.
6

Effect of UV radiation on survival of Salmonella enteritidis on the surface of ceramic tiles coated with TiO2

100%
Szczawinski J., Tomaszewski H., Jackowska-Tracz A., Szczawinska M. E.
Bulletin of the Veterinary Institute in Puławy
|
2010
|
tom 54
|
nr 4
The aim of this study was to determine and compare the antimicrobial activity of UV radiation of wavelength 253.7 nm (used in typical germicidal lamps) against Salmonella Enteritidis on the surfaces of conventionally produced white ceramic wall tiles (matt and shiny) and the same tiles coated with TiO₂, using three different methods: rf diode sputtering, atmospheric pressure chemical vapour deposition (APCVD), and spray pyrolysis deposition (SPD). Results clearly indicate that the bactericidal action of UV radiation is much stronger on the surfaces of tiles coated with TiO₂ than on the tiles uncovered. The strongest bactericidal effects of UV radiation was found for film prepared by APCVD, weaker for sputtering, and the weakest for SPD. Results of experiments for shiny and matt tiles did not differ statistically.
7

Effect of temperature on the growth kinetics of Salmonella Enteritidis in cooked ham

100%
Szczawinska M. E., Szczawinski J., Lobacz A.
Bulletin of the Veterinary Institute in Puławy
|
2014
|
tom 58
|
nr 1
The aim of the study was to determine a growth rate of Salmonella Enteritidis in cooked ham stored under different temperatures and to compare usefulness of the mathematical models for describing the microbiological data. The samples of cooked pork ham were inoculated with the mixture of three Salmonella Enteritidis strains and stored at 5°C, 10°C, 15°C for 21 d, and at 20°C and 25°C for 5 d. The number of salmonellae was determined at 10 periods of storage at each temperature. From each sample a series of decimal dilutions were prepared and plated onto Brilliant Green Agar. The plates were incubated at 37°C for 24-48 h under aerobic conditions. The colonies grown on culture media were counted, bacterial counts were multiplied by the appropriate dilutions, and number of bacteria (colony-forming units) was calculated. The bacterial counts were transformed into logarithms and analysed using IBM SPSS Statistics 20. The experiment was performed in five replicates. The obtained growth curves of bacteria were fitted to primary growth models, namely Gompertz, logistic, and Baranyi models. The goodness-of-fit test was evaluated by calculating mean square error and Akaike's criterion. Growth kinetics values from the modified Gompertz and logistic equations were calculated. It was found that in samples of ham stored at 5°C and 10°C for 21 d, the number of bacteria remained almost at the same level during storage. In samples stored at 15°C, 20°C, and 25°C growth of salmonellae was observed. It was found that logistic model gave in most cases the best fit to obtained microbiological data describing the behaviour of S. Enteritidis in cooked ham. The growth kinetics values calculated in this study from logistic equations can be used to predict potential S. Enteritidis growth in cooked ham stored at 15°C, 20°C, and 25°C.
8

Possibility of inactivation of Yersinia enterocolitica in vacuum-packed cheeses by ionizing radiation

88%
Szczawinski J., Stanczak B., Peconek J., Szczawinska M. E., Wisniewski J.
Polish Journal of Veterinary Sciences
|
2001
|
tom 04
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nr 4
9

Modelling the growth rate of Listeria monocytogenes in cooked ham stored at different temperatures

88%
Szczawinski J., Szczawinska M. E., Lobacz A., Tracz M., Jackowska-Tracz A.
Journal of Veterinary Research
|
2017
|
tom 61
|
nr 1
10

Evaluation of sensory acuity of students of the Faculty of Veterinary Medicine of Warsaw University of Life Sciences - SGGW in the years 1975-2015

76%
Szczawinski J., Plawinska-Czarnak J., Bogdan J., Szczawinska M. E., Zarzynska J., Jackowska-Tracz A.
Medycyna Weterynaryjna
|
2017
|
tom 73
|
nr 01
Veterinary students taking part in practical classes on “Hygiene of food of animal origin” course were tested on taste and odor identification as well as color differentiation. The results were subjected to statistical analysis to: (a) evaluate the influence of sex, smoking, time of day and status of health declared by the students on the results of tests; (b) determine the number of individuals who may fail the tests on taste and odor identification as well as color differentiation; (c) evaluate whether the sensory acuity of veterinary students changed in the 40 years of observation. The study involved 3310 students. A test for taste and odor identification was performed according to Polish Standard (PN-65/A-04021). The test for color differentiation was carried out using Rabkin color plates. The results of the study were elaborated using IBM SPSS Statistics 23. The chi-square test was used to determine whether there are significant differences between numbers of individuals assessed positively in particular experimental groups. The significance of the effect of experimental factors on the number of correctly identified samples was determined using analysis of variance. It was found that sex and smoking exerted a statistically significant effect (p < 0.01) on the number of subjects assessed positively and the number of correctly identified samples in three conducted tests. Female students more often than male students were assessed positively and correctly identified larger number of samples in all conducted tests. Nonsmokers obtained better results than smokers in all performed comparisons (significant difference at p < 0.01). It is worth noting that only 65.9% of students passed all three tests, and 1.3% of them did not pass any. In this last group were only men. The analysis of variance indicated that as time passed (since 1975 to 2015) sensory acuity of veterinary medicine students has increased.
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