Template-Type: ReDIF-Article 1.0 Author-Name: M. Leszczyocha Author-Workplace-Name: Institute of General Food Chemistry, Technical University of Łódź, Łódź, Poland Author-Name: U. Pytasz Author-Workplace-Name: Institute of General Food Chemistry, Technical University of Łódź, Łódź, Poland Title: The histamine content in some samples of food products Abstract: Histamine level determination in some food products was performed by two known methods: spectrofluorimetric method and ELISA method. The immunoenzymic method enables a rapid and precise determination of histamine in many samples. In spite of that, it does not require any complicated apparatus, is very simple and easy to use. Coefficient of correlation as stablished for these methods equals 0.9539. Samples were investigated of different products, such as: kefir, fruit and natural yoghurt, a kind of sour soup, and tinned fish (tuna and herring). No histamine content exceeding the acceptable level was found. Keywords: histamine, spectrofluorimetric methods, ELISA method, food Journal: Czech Journal of Food Sciences Pages: 81-86 Volume: 22 Issue: 3 Year: 2004 DOI: 10.17221/3410-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3410-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200403-0001.txt Handle: RePEc:caa:jnlcjf:v:22:y:2004:i:3:id:3410-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: V. Hábová Author-Workplace-Name: Department of Fermentation Chemistry and Bioengineering, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: K. Melzoch Author-Workplace-Name: Department of Fermentation Chemistry and Bioengineering, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: M. Rychtera Author-Workplace-Name: Department of Fermentation Chemistry and Bioengineering, Institute of Chemical Technology in Prague, Prague, Czech Republic Title: Modern method of lactic acid recovery from fermentation broth Abstract: Electrodialysis was used for lactic acid recovery from fermentation broth. In the first step, lactate was recovered and concentrated by desalting electrodialysis, and the second step was electroconversion of lactate to lactic acid by water-splitting electrodialysis. The final lactic acid concentration of 151 g/l was obtained. Total energy required in both electrodialysis processes was about 1.5 kWh per 1 kg of lactic acid obtained. The fermentation broth had to be pretreated prior to the electrodialysis experiments. The pretreatment consisted of ultrafiltration, decolourisation, and the removal of multivalent metal ions. Keywords: lactic acid recovery, electrodialysis, pretreatment of fermentation broth Journal: Czech Journal of Food Sciences Pages: 87-94 Volume: 22 Issue: 3 Year: 2004 DOI: 10.17221/3411-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3411-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200403-0002.txt Handle: RePEc:caa:jnlcjf:v:22:y:2004:i:3:id:3411-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: M. Halt Author-Workplace-Name: Faculty of Food Technology, University J. J. Strossmayer in Osijek, Osijek, Croatia Author-Name: T. Klapec Author-Workplace-Name: Faculty of Food Technology, University J. J. Strossmayer in Osijek, Osijek, Croatia Author-Name: Šubari Author-Workplace-Name: Faculty of Food Technology, University J. J. Strossmayer in Osijek, Osijek, Croatia Title: Fungal contamination of cookies and the raw materials for their production in croatia Abstract: The study examined fungal loads in different varieties of cookies, as well as in the raw materials used for their production in Croatia. The mean presence of various fungi in the final products and most of the raw materials was within acceptable levels. A higher contribution of major mycotoxigenic molds was detected in flour which makes cookies more susceptible to the accumulation of mycotoxins. Keywords: cookies, molds, mycotoxins Journal: Czech Journal of Food Sciences Pages: 95-98 Volume: 22 Issue: 3 Year: 2004 DOI: 10.17221/3412-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3412-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200403-0003.txt Handle: RePEc:caa:jnlcjf:v:22:y:2004:i:3:id:3412-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: B. E Hutapea Author-Workplace-Name: Department of Food Chemistry and Analysis, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: L. Parkányiová Author-Workplace-Name: Department of Food Chemistry and Analysis, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: J. Parkányiová Author-Workplace-Name: Department of Food Chemistry and Analysis, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: M. Miyahara Author-Workplace-Name: Department of Food Chemistry and Analysis, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: H. Sakurai Author-Workplace-Name: Department of Food Chemistry and Analysis, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: J. Pokorný Author-Workplace-Name: Department of Food Chemistry and Analysis, Institute of Chemical Technology in Prague, Prague, Czech Republic Title: Browning reactions between oxidised vegetable oils and amino acids Abstract: Browning reactions of oxidised lipids with amino acids were studied in mixtures of refined soybean or rapeseed oil with alanine, valine, lysine, serine, cystine, cysteine, methionine, proline, and tryptophan. Oils were deposited in thin layers on cellulose fibres impregnated with the individual amino acids. The reaction proceeded in the dark, in dry air, at 50°C and at free access of oxygen. The browning determined at 430 nm followed a nearly zeroth order reaction without any induction period. The browning was very weak in the absence of amino acids, and all amino acids increased the browning rate, especially cysteine, methionine, and even more proline and tryptophan. The reaction rates were nearly the same in mixtures with rapeseed and soybean oils. Small amounts of hydroperoxides did not appreciably affect the browning rate. In the presence of copper ions, which belong to the most active catalysts of oxidation, the reaction rate was substantially higher. On the contrary, in the presence of antioxidants, the reaction rate was reduced to a marked degree but no induction period was observed. The probable main reaction mechanism was the reaction of lipid hydroperoxides, free radicals produced by their decomposition and/or unsaturated aldehydes under the formation of unsaturated imines which further polymerised into brown macromolecular substances. Keywords: amino acids, autoxidation, browning, nonenzymic, hydroperoxides, imines, rapeseed oil, soybean oil Journal: Czech Journal of Food Sciences Pages: 99-107 Volume: 22 Issue: 3 Year: 2004 DOI: 10.17221/3413-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3413-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200403-0004.txt Handle: RePEc:caa:jnlcjf:v:22:y:2004:i:3:id:3413-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: J. Zídková Author-Workplace-Name: Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: J. Sajdok Author-Workplace-Name: Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: K. Kontrová Author-Workplace-Name: Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: A. Kotrbová-Kozak Author-Workplace-Name: Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: T. Hanis Author-Workplace-Name: Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: V. Zídek Author-Workplace-Name: Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, Institute of Chemical Technology in Prague, Prague, Czech Republic Author-Name: A. Fuíková Author-Workplace-Name: Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, Institute of Chemical Technology in Prague, Prague, Czech Republic Title: Effects of oxidised dietary cod liver oil on the reproductive functions of Wistar rat Abstract: Weanling Wistar rats, males and females, were fed for 185 days with diets containing 15% of dietary fat in the form of a mixture of lard and partially oxidised cod liver oil. The proportion of cod liver oil in the dietary fat ranged from 0 to 100%, and the content of malonaldehyde from 0.3 to 19.6 mg/kg of the fat used. Animals fed with diets containing higher proportions of oxidised cod liver oil had higher concentrations of malonaldehyde in their livers. Serum lipid levels were lower in animals fed with higher proportions of cod liver oil than in animals fed control diets (milk fat or lard). The lowest concentration of serum lipid was found in the rats fed the diet containing half of its fat as fish oil. Increased intakes of cod liver oil resulted in lower body weight gains, weights of livers, kidneys, and weights of the reproductive organs. The relative weights of livers and kidneys/body weight were higher in the groups with higher intakes of cod liver oil. High intakes of cod liver oil led to a drastically impaired fertility of females, a decreased litter size, a higher postnatal mortality, and an increased incidence of morphologically abnormal spermatozoa in males. Keywords: oxidised cod liver oil, rat, fertility, reproduction, organ weights Journal: Czech Journal of Food Sciences Pages: 108-120 Volume: 22 Issue: 3 Year: 2004 DOI: 10.17221/3414-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3414-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200403-0005.txt Handle: RePEc:caa:jnlcjf:v:22:y:2004:i:3:id:3414-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: R. Amarowicz Author-Workplace-Name: Department of Food Science, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland Author-Name: P. Zduńczyk Author-Workplace-Name: Department of Food Science, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland Author-Name: E. Flaczyk Author-Workplace-Name: Department of Food Science, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland Title: Capillary zone electrophoresis separation of hydrolysates obtained from food industry by-products Abstract: Enzymic hydrolysates were obtained from cracklings (CEH and CEH*) using alcalase. Acid hydrolysates were prepared from cracklings (CAH) and chicken feathers (FAH). The degree of hydrolysis (DH) of CEH and CEH* were 14 and 15.1%, respectively. CAH, its Sephadex G-25 fraction (CAH*) and FAH were characterised by DH of 53.8%, 47.8% and 46.2%. The electrophoreograms of enzymic hydrolysates were characterised by one high and sharp peak and several not base line separated peaks. More single and sharp peaks were observed on the electrophoreograms of acid hydrolysates. Migration times of the majority of peptides present in enzymic hydrolysates ranged between 4 and 6 min. Keywords: capillary zone electrophoresis, hydrolysates, cracklings, chicken feathers Journal: Czech Journal of Food Sciences Pages: 121-124 Volume: 22 Issue: 3 Year: 2004 DOI: 10.17221/3415-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3415-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200403-0006.txt Handle: RePEc:caa:jnlcjf:v:22:y:2004:i:3:id:3415-CJFS