Czech Journal of Food Sciences, 2005 (vol. 23), issue 6
Phthalates: toxicology and food safety - a review
Přemysl Mikula, Zdeňka Svobodová, Miriam Smutná
Czech J. Food Sci., 2005, 23(6):217-223 | DOI: 10.17221/3394-CJFS 
Phthalates are organic substances used mainly as plasticisers in the manufacture of plastics. They are ubiquitous in the environment. Although tests in rodents have demonstrated numerous negative effects of phthalates, it is still unclear whether the exposure to phthalates may also damage human health. This paper describes phthalate toxicity and toxicokinetics, explains the mechanisms of phthalate action, and outlines the issues relating to the presence of phthalates in foods.
Enzymatic activity in fermented milk products containing bifidobacteria
Iva Trojanová, Rada Vojtěch
Czech J. Food Sci., 2005, 23(6):224-229 | DOI: 10.17221/3395-CJFS
Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus and Bifidobacterium animalis strains were tested for á-galactosidase, â-galactosidase and á-glucosidase activities. Commercially available yoghurts with bifidobacteria were also tested. While bifidobacteria produced all the enzymes mentioned above, lactobacilli and streptococci exhibited only â-galactosidase activity. In yoghurts, only â-galactosidase was detected, while practically no á-galactosidase, and in one product only little á-glucosidase activities were exhibited. It could be concluded that the consumption of bifidobacteria via yoghurt...
Oxidative changes of vegetable oils during microwave heating
Jana Dostálová, Pavel Hanzlík, Zuzana Réblová, Jan Pokorný
Czech J. Food Sci., 2005, 23(6):230-239 | DOI: 10.17221/3396-CJFS
The oxidative stabilities of pork lard, sunflower, zero-erucic rapeseed, peanut and high-oleic peanut oils were tested under microwave heating conditions. Vegetable oils and lard were heated in a microwave oven for up to 40 min between 25°C and 200°C. The peroxide value, the contents of conjugated dienoic and trienoic acids, and polymers were used as markers of lipid degradation. Sunflower oil was found the least stable oil because of a high polyenoic acid content and a low content of γ-tocopherol. Rapeseed oil was more stable because of a lower polyenoic acid content and a high γ-tocopherol level. Conventional peanut oil was relatively...
Use of video image analysis for the evaluation of beef carcasses
Oldřich Smékal, Petr Pipek, Mitsuyoshi Miyahara, Jarmila Jeleníková
Czech J. Food Sci., 2005, 23(6):240-245 | DOI: 10.17221/3397-CJFS
Video image analysis was used for the objective evaluation of beef carcasses parts as an additional parameter of the carcass classification. The pictures of cross sections of dorsal parts of beef carcasses between 8th and 9th vertebra were taken under industrial conditions and evaluated using LUCIA software. The areas of muscle and adipose tissues were thresholded on several ways (the whole loin area, the areas of individual muscles and those of different loin sections) and the correlations between these areas were searched. The best correlations were found between large areas. Video image analysis proved to be a suitable method...
Changes in selected vitamins, microorganism counts, and sensory quality during storage of pressurised sprouted seed of alfalfa (Medicago sativa L.)
Dana Gabrovská, Ivana Paulíčková, Eva Mašková, Vlasta Fiedlerová, Kateřina Kocurová, Jiřina Průchová, Jan Strohalm, Milan Houška
Czech J. Food Sci., 2005, 23(6):246-250 | DOI: 10.17221/3398-CJFS
The aim of this study was to examine the changes of nutritional and sensory quality of sprouted alfalfa seed treated by high pressure, that take place during storage. Along with this, microbiological safety was also observed. Sprouted alfalfa seed in citric acid pickle, packed in transparent laminated bags PA/PE 80, was treated with 500 MPa high pressure for 10 minutes. The processed seed in bags was stored in a refrigerator for 21 days. The bags were sampled in regular intervals to perform analyses. The changes in the contents of vitamin C, riboflavin, niacin, and pantothenic acid were observed during storage. The same samples were also checked for...
Quantitative analysis of chloramphenicol residues in shrimp muscle tissues by Chemiluminescent enzyme immunoassay
Xu Chuanlai, Peng Cifang, Hao Kai, Jin Zhengyu, Wang Wukang
Czech J. Food Sci., 2005, 23(6):251-256 | DOI: 10.17221/3399-CJFS
A competitive indirect chemiluminescent enzyme immunoassay (ic-CLEIA) has been developed for the determination of chloramphenicol (CAP) residues in shrimp. After the optimisation of four physico-chemical parameters, i.e. incubation time, concentration of Tween-20, concentration of PBS and its pH, the method developed gave a limit of detection of 0.01 ng/ml and a detection range from 0.03 ng/ml to 23.7 ng/ml, with an ED50 of 0.47 ng/ml. The developed method has been validated on spiked shrimp samples in terms of precision (intra- and interassay coefficient variations of less than 10% and 15%, respectively), and of accuracy (mean recovery...