Czech Journal of Food Sciences, 2012 (vol. 30), issue 6
Index of volume 30 (2012), Author index, Author Institutions index, Subject indexIndex
editors
Czech J. Food Sci., 2012, 30(6):I-XV | DOI: 10.17221/6461-CJFS 
Physical methods of resveratrol induction in grapes and grape products - a review
Jan TŘÍSKA, Milan HOUŠKA
Czech J. Food Sci., 2012, 30(6):489-502 | DOI: 10.17221/115/2012-CJFS
Trans-resveratrol ((E)-3,4',5-trihydroxystilbene) is a substance that is produced by a large number of plants as a phytoalexin and has a wide range of beneficial biological properties. Resveratrol has been credited as being potentially responsible for the "French paradox" - the observation that the French have a relatively low incidence of coronary heart disease, even though their diet is high in saturated fats. This review deals with the methods serving for the increase of the resveratrol content in wine products - wine and grape juices. The methods reviewed are UV irradiation of grapes and ozonisation of grapes. The discussed methods...
Comparison of farmed and wild common carp (Cyprinus carpio): Seasonal variations in chemical composition and fatty acid profile
Sakineh Yeganeh, Bahareh Shabanpour, Hedayat Hosseini, Mohammad Reza Imanpour, Ali Shabani
Czech J. Food Sci., 2012, 30(6):503-511 | DOI: 10.17221/455/2011-CJFS
Chemical composition and fatty acid profile of fillets from farmed and wild common carp were assessed in the course of four seasons. Ten wild and ten0 farmed fish were collected in the middle month of each season (except summer due to unavailability of wild fish) during the year. Lipid and protein contents of the samples decreased from summer to spring (protein: 17.6 ± 0.3-15.9 ± 1.6; 18.2 ± 0.1-17.9 ± 1.4%, in the farmed and wild carp samples, lipid (5.1 ± 0.2-1.5 ± 0.5; 3.8 ± 0.6-2.8 ± 0.9%, respectively; P > 0.05), moisture content of both samples increased in this period (76.7 ± 1.4-81.4...
Estimation of the shelf-life of halloumi cheese using survival analysis
Rabih KAMLEH, Imad TOUFEILI, Rola AJIB, Bilal KANSO, John HADDAD
Czech J. Food Sci., 2012, 30(6):512-519 | DOI: 10.17221/233/2011-CJFS
Halloumi cheese blocks, packaged in vacuum polyamide/polyethylene laminate bags, were stored at 5, 15, and 25°C. The changes in total bacterial count, lactic acid bacteria, total anaerobic bacteria, yeasts and molds, pH, and titratable acidity were monitored during the storage. The appearance of the packaged Halloumi cheese exhibited significant correlations with the counts of the different microbial populations inhabiting the cheese. The shelf-life of the stored Halloumi cheese was determined using survival analysis and considering consumer rejection as a failure index. The nominal shelf-lives of Halloumi cheese were 79.6, 37.8, and 2.6 days when...
Pollen and inorganic characteristics of Bulgarian unifloral honeys
Juliana ATANASSOVA, Lilyana YURUKOVA, Maria LAZAROVA
Czech J. Food Sci., 2012, 30(6):520-526 | DOI: 10.17221/44/2012-CJFS
The melissopalynological characteristics, three main physicochemical parameters (water content, pH, and electrical conductivity), and 19 macro- and microelements contents of 15 honey types from throughout Bulgariathat were collected from 2006 to 2009 were evaluated. The main honeys studied came from Robinia pseudoacacia L., Helianthus annuus L., Brassica spp., Tilia spp., and Vicia spp. The botanical origins of unifloral honey samples were identified as Lotus spp., Coriandrum sativum L., Daucus-type, Stachys-type, Salix spp., Prunus...
Lipid oxidation of fat blends modified by monoacylglycerol
Veronika Spěváčková, Iveta Hrádková, Jan Šmidrkal, Vladimir Filip
Czech J. Food Sci., 2012, 30(6):527-533 | DOI: 10.17221/459/2011-CJFS
Model dispersions of fat blends (FBs) with monoacylglycerols (MAG) of saturated fatty acids with different lengths of the acyl chain (MAG10-MAG18) and 1-octadecenoylglycerol and without MAG (as blank) were prepared. We find out the influence of the addition of monoacylglycerol on oxidation of the fat dispersion. Trihexadecanoylglycerol (tripalmitoylglycerol - TAG48) was used as the dispersive phase and soybean oil was used as the dispersive medium. Primary (conjugated diens) and volatile secondary (by SPME in connection with GC-MS) lipid oxidation products and oil stability index (OSI) were measured during autoxidation of the fat blends in storage...
Effects of whole buckwheat flour on physical, chemical, and sensory properties of flat bread, Lavaş
Gökçen YILDIZ, Nermin BILGIÇLI
Czech J. Food Sci., 2012, 30(6):534-540 | DOI: 10.17221/10/2012-CJFS
The whole buckwheat flour (WBF) was used in Turkish flat bread, lavaş, up to 30% level without gluten, and up to 40% level with gluten and sodium stearoyl-2-lactylate (SSL) additions. Some physical, chemical, and sensory properties of lavaş bread samples were determined. While ash, crude fiber, phytic acid (PA), Fe, K, Mg, and P contents of lavaş breads increased with WBF addition, gluten supplementation caused an increase especially in protein and Ca contents. Leavening process decreased PA contents in the breads compared to raw material, but WBF substitution increased PA contents up to 729 mg/100 g. As a result, the utilisation of WBF in lavaş bread...
Influence of growing area, plant age, and virus infection on the contents of hop secondary metabolites
Lukáš JELÍNEK, Monika DOLEČKOVÁ, Marcel KARABÍN, Tereza HUDCOVÁ, Blanka KOTLÍKOVÁ, Pavel DOSTÁLEK
Czech J. Food Sci., 2012, 30(6):541-547 | DOI: 10.17221/50/2012-CJFS
Hops and hop products (pellets and extracts) belong to the major raw materials employed in brewing industry. Many effects such as the growing area, hop plant age, and virus infection influence the contents of the brewing-important hop secondary metabolites (α- and β-bitter acids, essential oils, and polyphenols). The clones of the Czech cultivars Saaz and German cv. Taurus were used in this work and compared with the aim to investigate the influence of the effects mentioned on the contents of hop secondary metabolites.
Effect of Maillard reaction on reducing power of malts and beers
Lucie Čechovská, Michael Konečný, Jan VELÍŠEK, Karel CEJPEK
Czech J. Food Sci., 2012, 30(6):548-556 | DOI: 10.17221/288/2012-CJFS
HPLC with amperometric detection was used to evaluate the reducing power of 23 beers and aqueous extracts of 17 barley malts. While brew pale malts were only slightly higher in electrochemical reducing capacity than natural barleys (about 1.3 g BHAE/kg), caramel malts with the colour of 60-450°EBC showed 7.5-17.2 g BHAE/kg. The superior reducing power of the darker caramel malts was partly due to the presence of a Maillard-derived 2,3-dihydro-3,5-dihydroxy-6-methyl-(4H)-pyran-4-one (DDMP), which was responsible for 21-55% of their electrochemical capacity. Among common brew malts, only the Munich type showed a significantly increased electrochemical...
Preparation of mango (Mangifera indica L.) wine using a new yeast-mango-peel immobilised biocatalyst system
Sadineni Varakumar, Kondapalli Naresh, Obulam Vijaya Sarathi Reddy
Czech J. Food Sci., 2012, 30(6):557-566 | DOI: 10.17221/478/2011-CJFS
The preparation of mango wine by yeast-mango peel immobilised biocatalyst system by repeated batch fermentation was conducted and compared to free cells fermentation at 15, 20, 25, and 30°C. The operational stability of the biocatalyst was good as the ethanol concentrations (76.0-96.0 g/l) and productivities (1.53-3.29 g/l/h) were high, showing the suitability of the biocatalyst for even low temperature winemaking. The concentration of ethyl acetate was not above 40 mg/l in all cases, and higher alcohols were low (< 330 mg/l) in wine with immobilised cells indicating an improvement in the product compared to free cells fermentation. Amyl alcohols...
Monoacylglycerols as fruit juices preservatives
Iva DOLEŽÁLKOVÁ, Zdeněk MÁČALÍK, Adéla BUTKOVIČOVÁ, Rahula JANIŠ, Leona BUŇKOVÁ
Czech J. Food Sci., 2012, 30(6):567-572 | DOI: 10.17221/485/2011-CJFS
Limiting or preventing the growth of undesirable microbial flora in food products is one of the main goals of food microbiology. A number of preservation methods have been designed to extend the shelf-life of the food products by reducing the microbial growth while new antimicrobials are still examined. Monoglycerides are naturally occurring compounds with inhibitory activity against various microorganisms. We evaluate the antimicrobial effects of 8 monoglycerides in vitro and in fresh unpasteurised apple juice. Out of all monoglycerides tested, monocaprin (MAG C10:0) and monolaurin (MAG C12:0) showed the best ability to supress or prevent...
Antimicrobial activities of medium-chain fatty acids and monoacylglycerols on Cronobacter sakazakii DBM 3157T and Cronobacter malonaticus DBM
Milan Marounek, Vannaphone Putthana, Oldřich Benada, Daniela Lukešová
Czech J. Food Sci., 2012, 30(6):573-580 | DOI: 10.17221/433/2011-CJFS
Cronobacter sakazakii and Cronobacter malonaticus are pathogens causing infections in children that are primarily linked to the consumption of contaminated infant milk formula and food. Both Cronobacter strains examined were susceptible to caprylic acid, monocaprylin and, to a lesser extent, sorbic acid. Capric acid, lauric acid, monosorbin, monocaprin, monolaurin, and sucrose caprate exhibited no inhibitory activity. Caprylic acid and monocaprylin treatment (2 mg/ml) of C. sakazakii DBM 3157T reduced the number of viable cells by five orders of magnitude. In the case of C. malonaticus DBM 3148,...