Czech Journal of Food Sciences, 2004 (vol. 22), issue 3
The histamine content in some samples of food products
M. Leszczyocha, U. Pytasz
Czech J. Food Sci., 2004, 22(3):81-86 | DOI: 10.17221/3410-CJFS 
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.
Modern method of lactic acid recovery from fermentation broth
V. Hábová, K. Melzoch, M. Rychtera
Czech J. Food Sci., 2004, 22(3):87-94 | DOI: 10.17221/3411-CJFS
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.
Fungal contamination of cookies and the raw materials for their production in croatia
M. Halt, T. Klapec, ©ubari
Czech J. Food Sci., 2004, 22(3):95-98 | DOI: 10.17221/3412-CJFS
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.
Browning reactions between oxidised vegetable oils and amino acids
B. E Hutapea, L. Parkányiová, J. Parkányiová, M. Miyahara, H. Sakurai, J. Pokorný
Czech J. Food Sci., 2004, 22(3):99-107 | DOI: 10.17221/3413-CJFS
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...
Effects of oxidised dietary cod liver oil on the reproductive functions of Wistar rat
J. Zídková, J. Sajdok, K. Kontrová, A. Kotrbová-Kozak, T. Hanis, V. Zídek, A. Fuíková
Czech J. Food Sci., 2004, 22(3):108-120 | DOI: 10.17221/3414-CJFS
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...
Capillary zone electrophoresis separation of hydrolysates obtained from food industry by-products
R. Amarowicz, P. Zduńczyk, E. Flaczyk
Czech J. Food Sci., 2004, 22(3):121-124 | DOI: 10.17221/3415-CJFS
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...