Template-Type: ReDIF-Article 1.0 Author-Name: A. Mižáková Author-Workplace-Name: Department of Food Hygiene and Technology, University of Veterinary Medicine, Košice, Slovak Republic Author-Name: M. Pipová Author-Workplace-Name: Department of Food Hygiene and Technology, University of Veterinary Medicine, Košice, Slovak Republic Author-Name: P. Turek Author-Workplace-Name: Department of Food Hygiene and Technology, University of Veterinary Medicine, Košice, Slovak Republic Title: The occurrence of moulds in fermented raw meat products Abstract: The consumption of food contaminated with moulds (microscopic filamentous fungi) and their toxic metabolites results in the development of food-borne mycotoxicosis. The spores of moulds are ubiquitously spread in the environment and can be detected everywhere. In this study, the presence of various moulds was determined in pork and beef used as a raw material, in salami emulsions, as well as in five kinds of fermented raw meat products. Penicillium sp., Acremonium sp., Mucor sp., Cladosporium sp., and Aspergillus sp. were the most frequently isolated genera of moulds. Flavourings added to meat during the production of fermented raw meat products were heavily contaminated with moulds. The widest spectrum and the highest counts of microscopic filamentous fungi were observed in the following spices: milled black pepper, nutmeg, garlic powder and crushed caraway. The level of contamination depended upon the season, being higher in the summer months. Keywords: fermented meat products, moulds, microscopic filamentous fungi, mycotoxins, spices Journal: Czech Journal of Food Sciences Pages: 89-94 Volume: 20 Issue: 3 Year: 2002 DOI: 10.17221/3516-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3516-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200203-0001.txt Handle: RePEc:caa:jnlcjf:v:20:y:2002:i:3:id:3516-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: A. Prošková Author-Workplace-Name: Food Research Institute Prague, Prague, Czech Republic Author-Name: J. Kučera Author-Workplace-Name: Food Research Institute Prague, Prague, Czech Republic Title: Immobilized metal ion chromatographic (IMAC) determination of ovomucoid in hen's egg white Abstract: An immobilized metal ion high-performance liquid chromatographic technique was developed for the determination of one of the egg allergens - ovomucoid - in egg white and food products containing egg white. The method was tested using standard samples as well as complete egg white and its reproducibility was determined. The possible application of this method is discussed. The method is based on the HPLC chromatography on the chelating column saturated with copper ions. The sample is applied to the column at pH 7.5 and eluted isocraticaly with a buffer containing 1.75 mM imidazole in the optimum case. Keywords: ovomucoid, determination, HPL.C, egg white, analytical method, IMAC, HPLC Journal: Czech Journal of Food Sciences Pages: 95-97 Volume: 20 Issue: 3 Year: 2002 DOI: 10.17221/3517-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3517-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200203-0002.txt Handle: RePEc:caa:jnlcjf:v:20:y:2002:i:3:id:3517-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: Mohamed Fawzy Ramadan Author-Workplace-Name: Institute of Food Chemistry, Technical University of Berlin, Berlin, Germany Author-Name: Jörg-Thomas Mörsel Author-Workplace-Name: Institute of Food Chemistry, Technical University of Berlin, Berlin, Germany Title: Proximate neutral lipid composition of niger (Guizotia abyssinica Cass.) seed Abstract: Niger (Guizotia abyssinica Cass.) seed was extracted with hexane (H) and chloroform/methanol (CM) (2:1, v/v) to determine the effect of the solvent on the amount and composition of the recovered lipid. The amount of the total lipid (TL) extracted with H was 29.6% of the seed weight, while that extracted with CM was 49.9%. Column and thin-layer chromatographic procedures on Silica Gel were performed to fractionate the main neutral lipid (NL) subclasses. Fatty acid composition of the NL subclasses, triacylglycerol (TAG) molecular species, and sterol (ST) content were estimated. The NL amount was found to be higher (97% of TL) in the H extract than in the CM extract (93% of TL). TAG appeared to be the predominant NL subclass (89.7-91.9% of total NL). Linoleic acid (C18:2n-6) was the main fatty acid followed by oleic acid (C18:1n-9) as the second main unsaturated fatty acid, while palmitic acid (C16:0) was the major saturated fatty acid. With high temperature gas-liquid chromatography using a flame ionization detector (HTGLC/FID) and H2 as the carrier gas, the actual TAG molecular species according to their carbon numbers were separated. TAG of even carbon numbers 16 and 18 were contained in six TAG molecular species. The major peaks occured at C54:6, and C54:3 corresponding to trilinolein and triolein. Furthermore, TAG molecular specie, expected to contain two molecules of linoleic acid (C54:5), was detected in a high level. Phytosterol pattern was determined without derivatization in the unsaponifiable fractions by HTGLC/FID. ST profile was characterized by a high total amount accounting for 4.22 g/kg of total H extract, and 4.00 g/kg of total CM extract. b-Sitosterol (2.035-1.929 g/kg TL) was the main component in both extracts. The major ST found were, in order of decreasing prevalence, b-sitosterol > campesterol > stigmasterol > D5-ave-nasterol > D7-avenasterol > lanosterol. Keywords: Guizotia abyssinica Cass., niger seed, seed oil, neutral lipid subclasses, fatty acids, triacylglycerols, sterols Journal: Czech Journal of Food Sciences Pages: 98-104 Volume: 20 Issue: 3 Year: 2002 DOI: 10.17221/3518-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3518-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200203-0003.txt Handle: RePEc:caa:jnlcjf:v:20:y:2002:i:3:id:3518-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: B. Hozová Author-Workplace-Name: Faculty of Chemical and Food Technology, Slovak Technical University in Bratislava, Slovak Republic Author-Name: I. Kukurová Author-Workplace-Name: Faculty of Chemical and Food Technology, Slovak Technical University in Bratislava, Slovak Republic Author-Name: R. Turicová Author-Workplace-Name: Faculty of Chemical and Food Technology, Slovak Technical University in Bratislava, Slovak Republic Author-Name: L. Dodok Author-Workplace-Name: Faculty of Chemical and Food Technology, Slovak Technical University in Bratislava, Slovak Republic Title: Sensory quality of stored croissant-type bakery products. Abstract: The results are presented of the estimation of sensory quality (shape, odour, colour, taste, consistency, crust, crumb etc.), mould and yeast counts, aw value, and pH in 8 bakery croissant-type products with nougat cream filling during storage under laboratory conditions (20 ± 2°C) for the periods of up to 90 days (0; 30; 45; 60; 75 and 90 days). The products differed in the type of dough (brioche, croissant), the aw value of the cream, and in the presence or absence of sorbic acid in the spirit spray applied onto the surface of the products under investigation. The above-indicated parameters were examined also in the nougat cream samples on day 0 and 90 of the storage. The selected quality parameters permitted to estimate the shelf life of the products in the dependence on various technological conditions (sorbic acid, recipe, aw value). Keywords: croissants, sensory evaluation, moulds and yeasts, aw, pH, sorbic acid Journal: Czech Journal of Food Sciences Pages: 105-112 Volume: 20 Issue: 3 Year: 2002 DOI: 10.17221/3519-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3519-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200203-0004.txt Handle: RePEc:caa:jnlcjf:v:20:y:2002:i:3:id:3519-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: Ľ. Polívka Author-Workplace-Name: Department of Environmental and Safety Engineering, Faculty of Material Technology, Slovak Technical University, Trnava, Slovak Republic Author-Name: E. Fendrich Author-Workplace-Name: Department of Environmental and Safety Engineering, Faculty of Material Technology, Slovak Technical University, Trnava, Slovak Republic Author-Name: B. Škárka Author-Workplace-Name: Department of Environmental and Safety Engineering, Faculty of Material Technology, Slovak Technical University, Trnava, Slovak Republic Title: Influence of ozone on properties of jams Abstract: The influence of ozone on some properties of fruit jams was studied. Ozone did not influence the pH value, the contents of reducing sugars and organic acids, or the sensoric properties of the fruit jams tested. It may be used as a source of sterile air over the jam surfaces in yoghurt production. Keywords: ozone, fruit jams, sensoric properties, yoghurt Journal: Czech Journal of Food Sciences Pages: 113-115 Volume: 20 Issue: 3 Year: 2002 DOI: 10.17221/3520-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3520-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200203-0005.txt Handle: RePEc:caa:jnlcjf:v:20:y:2002:i:3:id:3520-CJFS Template-Type: ReDIF-Article 1.0 Author-Name: J. Houšová Author-Workplace-Name: Food Research Institute Prague, Prague, Czech Republic Author-Name: K. Hoke Author-Workplace-Name: Food Research Institute Prague, Prague, Czech Republic Title: Microwave heating - the influence of oven and load parameters on the power absorbed in the heated load Abstract: The microwave power is a parameter greatly influencing the rate of heating. Several authors reported on certain differences between the rated power output as a parameter used by oven manufacturers in the labelling of ovens, and the power actually delivered to the heated product. A review of the respective information is given in this article together with the results of own experiments following the influence of the oven type and the heated substance parameters on the power actually absorbed in the substance volume during its heating. As the heated substance, water and solutions of NaCl and sucrose of different concentrations were used. For the heating, four types of domestic microwave ovens and glass and plastic containers, were used. The decreasing of the efficiency of heating with the decreasing volume of the heated substance and a certain relation between the rate of this decrease and the types of oven and of substance was estimated. With the small cavity ovens, a lower rate of the decrease of the absorbed microwave power with the decreasing volume of the substance was found as compared to the large cavity oven. A certain influence of other technical oven parameters is shown in the comparison of the tests results with the ovens of the same rated power and the cavity volume. In addition to the substance volume, also its dielectric properties probably influence the microwave power absorbed in small samples during the heating. No simple dependence can be seen on the basis of the tests results between the type of container used in the tests and the power absorbed in the heated substance. Keywords: microwave heating, microwave power, power absorption Journal: Czech Journal of Food Sciences Pages: 117-124 Volume: 20 Issue: 3 Year: 2002 DOI: 10.17221/3521-CJFS File-URL: http://cjfs.agriculturejournals.cz/doi/10.17221/3521-CJFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjf-200203-0006.txt Handle: RePEc:caa:jnlcjf:v:20:y:2002:i:3:id:3521-CJFS