Template-Type: ReDIF-Article 1.0 Author-Name: Jan Velíšek Author-Workplace-Name: Department of Food Chemistry and Analysis, Faculty of Food and Biochemical Technology, Institute of Chemical Technology Prague, Prague, Czech Republic Author-Name: Roman Kubec Author-Workplace-Name: Department of Food Chemistry and Analysis, Faculty of Food and Biochemical Technology, Institute of Chemical Technology Prague, Prague, Czech Republic Author-Name: Karel Cejpek Author-Workplace-Name: Department of Food Chemistry and Analysis, Faculty of Food and Biochemical Technology, Institute of Chemical Technology Prague, Prague, Czech Republic Title: Biosynthesis of food constituents: Peptides - a review Abstract: This review article gives a brief survey of principal pathways that lead to the biosynthesis of most important peptides occurring in foods. Glutathione, selected plant γ-glutamyl peptides, and animal histidine dipeptides are included in this review. Keywords: biosynthesis, glutathione, γ -glutamyl peptides, S-alk(en)ylcysteine sulfoxides, phytochelatins, histidine dipeptides, carnosine, anserine, balenine Journal: Czech Journal of Food Sciences Pages: 149-155 Volume: 24 Issue: 4 Year: 2006 DOI: 10.17221/3311-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3311-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200604-0001.txt Handle: RePEc:caa:jnlcjf:v:24:y:2006:i:4:id:3311-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: Pavlína Navrátilová Author-Workplace-Name: Department of Milk Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Author-Name: Bohumíra Janštová Author-Workplace-Name: Department of Milk Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Author-Name: Petra Glossová Author-Workplace-Name: Department of Milk Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Author-Name: Lenka Vorlová Author-Workplace-Name: Department of Milk Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Title: Freezing point of heat-treated drinking milk in the Czech Republic Abstract: In theCzechRepublic, the freezing point of milk is presently used as a quality indicator of cows' raw milk as well as of heat-treated drinking milk, and its limit value is ≤ -0.520°C. Of the total of 295 drinking milk samples examined over a period of one year, 145 were samples of pasteurised milk and 150 were samples of UHT milk. In compliance with the Czech State Standard57 05 38, the freezing point was determined by a thermistor cryoscope. The measured mean value of the freezing point of the heat-treated drinking milk was -0.515°C ± 0.0078. A total of 207 (70.2%) samples of the heat-treated drinking milk, i.e. 93 (64.1%) samples of pasteurised and 114 (76%) samples of UHT milk, were found above the maximum limit value. The unsatisfactory results of the monitoring of the freezing point of drinking milk emphasise the need for a reassessment of the current system of the milk quality evaluation with respect to this quality index. Keywords: cow milk, pasteurised milk, UHT milk, physicochemical properties, milk duality Journal: Czech Journal of Food Sciences Pages: 156-163 Volume: 24 Issue: 4 Year: 2006 DOI: 10.17221/3313-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3313-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200604-0002.txt Handle: RePEc:caa:jnlcjf:v:24:y:2006:i:4:id:3313-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: Hrvoje Pavlović Author-Workplace-Name: Faculty of Food Technology, Josip Juraj Strossmayer University in Osijek, Osijek, Croatia Author-Name: Jovica Hardi Author-Workplace-Name: Faculty of Food Technology, Josip Juraj Strossmayer University in Osijek, Osijek, Croatia Author-Name: Vedran Slačanac Author-Workplace-Name: Faculty of Food Technology, Josip Juraj Strossmayer University in Osijek, Osijek, Croatia Author-Name: Marija Halt Author-Workplace-Name: Faculty of Food Technology, Josip Juraj Strossmayer University in Osijek, Osijek, Croatia Author-Name: Dragana Kocevski Author-Workplace-Name: Faculty of Food Technology, Josip Juraj Strossmayer University in Osijek, Osijek, Croatia Title: Inhibitory effect of goat and cow milk fermented by Bifidobacterium longum on Serratia marcescens and Campylobacter jejuni Abstract: This study was performed to determine the influence of fermented goat and cow milk produced by the use of Bifidobacterium longum Bb-46 on pathogenic Serratia marcescens and Campylobacter jejuni strains. The correlation between the inhibitory effect and some fermentation parameters (the number of viable probiotic cells and pH of fermented milk) was also determined. Bifidobacterium longum counts and pH values were also measured in milk samples during fermentation. The results showed that the inhibitory effect of Bifidobacterium longum Bb-46 fermented goat milk on Serratia marcescens increased with the fermentation time. The highest inhibitory effect of fermented cow milk occurred in the middle course of fermentation. Statistically significant correlation between the inhibition degree of Serratia marcescens growth and pH values of fermented goat milk was noted as opposed to the correlation between the inhibition degree of Serratia marcescens growth and pH values of fermented cow milk which was not statistically significant. All samples of goat and cow fermented milk exhibited inhibitory effects on the growth of Campylobacter jejuni. Keywords: Bifidobacterium longum, Campylobacter jejuni, fermented goat and cow milk, inhibitory effect, Serratia marcescens Journal: Czech Journal of Food Sciences Pages: 164-171 Volume: 24 Issue: 4 Year: 2006 DOI: 10.17221/3312-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3312-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200604-0003.txt Handle: RePEc:caa:jnlcjf:v:24:y:2006:i:4:id:3312-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: Blanka Svejkovská Author-Workplace-Name: Department of Food Chemistry and Analysis, Faculty of Food and Biochemical Technology, Institute of Chemical Technology Prague, Prague, Czech Republic Author-Name: Marek Doležal Author-Workplace-Name: Department of Food Chemistry and Analysis, Faculty of Food and Biochemical Technology, Institute of Chemical Technology Prague, Prague, Czech Republic Author-Name: Jan Velíšek Author-Workplace-Name: Department of Food Chemistry and Analysis, Faculty of Food and Biochemical Technology, Institute of Chemical Technology Prague, Prague, Czech Republic Title: Formation and decomposition of 3-chloropropane-1,2-diol esters in models simulating processed foods Abstract: The formation of 3-chloropropane-1,2-diol (3-MCPD) released from its esters with higher fatty acids was studied using the recognised precursors of 3-MCPD (tripalmitin, 1,3-dipalmitin, 1-monopalmitin and soybean oil) in the presence of sodium chloride. The precursors were reacted with sodium chloride in an emulsion stabilised with an emulsifier under conditions which modelled the thermal treatment of foods during processing. The highest amount of bound 3-MCPD (released from its esters) was formed from 1-monopalmitin followed by 1,3-dipalmitin, whereas tripalmitin and soybean oil yielded the lowest levels of bound 3-MCPD. Four sets of experiments were then carried out aimed at monitoring the influence of various factors (soybean oil amount, NaCl content, water content, and temperature) on the yield of bound 3-MCPD. The formation of bound 3-MCPD was directly proportional to the concentration of either oil or NaCl. The highest amount of bound 3-MCPD was formed in media containing approximately 20% water. The amount of bound 3-MCPD decreased with increasing temperature over the range 100-230°C and reached its highest value at 100°C. Models with 1,2-dipalmitoyl-3-chloropropane-1,2-diol showed that the decomposition rate of this ester rapidly increased with increasing temperature over the range 100-230°C being the lowest at 100°C and the highest at 230°C. Keywords: chloropropanols, 3-chloropropane-1, 2-diol, 3-MCPD, bound 3-MCPD, 3-MCPD esters, lipids, contaminants Journal: Czech Journal of Food Sciences Pages: 172-179 Volume: 24 Issue: 4 Year: 2006 DOI: 10.17221/3314-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3314-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200604-0004.txt Handle: RePEc:caa:jnlcjf:v:24:y:2006:i:4:id:3314-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: Petr Šmerák Author-Workplace-Name: Department of General Biology and Genetics, Center of Biomedical Sciences, 3 rd Faculty of Medicine, Charles University, Prague, Czech Republic Author-Name: Helena Šestáková Author-Workplace-Name: National Institute of Public Health, Prague, Czech Republic Author-Name: Zdeňka Polívková Author-Workplace-Name: Department of General Biology and Genetics, Center of Biomedical Sciences, 3 rd Faculty of Medicine, Charles University, Prague, Czech Republic Author-Name: Rudolf Štětina Author-Workplace-Name: Faculty of Military Health Sciences, Department of Toxicology, Hradec Kralové, Czech Republic$2 Author-Name: Martina Langová Author-Workplace-Name: Department of General Biology and Genetics, Center of Biomedical Sciences, 3 rd Faculty of Medicine, Charles University, Prague, Czech Republic Author-Name: Ivo Bárta Author-Workplace-Name: Department of General Biology and Genetics, Center of Biomedical Sciences, 3 rd Faculty of Medicine, Charles University, Prague, Czech Republic Author-Name: Bohumil Turek Author-Workplace-Name: National Institute of Public Health, Prague, Czech Republic Author-Name: Jiřina Bártová Author-Workplace-Name: Department of General Hygiene, Center of Preventive Medicine, rd 3 Faculty of Medicine, Charles University, Prague, Czech Republic Title: Antimutagenic effect of epigallocatechin gallate and its effect on the immune response in mice Abstract: Green tea is the second-most consumed beverage in the world (water is the first one) and has been used medicinally for centuries in Indiaand China. The active substances in the green tea are polyphenols (catechins) and flavonols which possess a potent antioxidant activity. Epigallocatechin gallate (EGCG) is one of the four major green tea catechins. Using the Ames test, micronucleus test, comet assay, chemiluminescence test, and blastic transformation test, we examined the antimutagenic effects of chemoprotective substance epigallocatechin gallate (EGCG) in the pure form on the mutagenicity induced by three reference mutagens: aflatoxin B1 (AFB1), 2-amino-3-methylimidazo [4,5-f] qui-noline (IQ), and N-nitroso-N-methylurea (MNU), and the effect of EGCG on the immunosuppression caused by these mutagens. Using the Ames test the dose dependent antimutagenic activity of EGCG was proved against indirect mutagens AFB1 and IQ, but not against the direct mutagen MNU. In the micronucleus test, EGCG had antimutagenic effect upon all three mutagens. EGCG decreased the level of DNA breaks induced by AFB1 in bone marrow cells and colon epithelium, and the level of DNA breaks induced by MNU in colon cells to the level found in control. The reparatory effect of EGCG on immunosupression induced by all three carcinogenic compounds was proved using chemiluminescence and blastic trasformation tests. Keywords: epigallocatechin gallate, antimutagenic effects, effect on the immune response, Ames test, micronucleus test, comet assay, chemiluminescence and blastic transformation tests Journal: Czech Journal of Food Sciences Pages: 180-192 Volume: 24 Issue: 4 Year: 2006 DOI: 10.17221/3315-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3315-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200604-0005.txt Handle: RePEc:caa:jnlcjf:v:24:y:2006:i:4:id:3315-CJFS