Czech Journal of Food Sciences, 2011 (vol. 29), issue 2
Pigments of higher fungi - a review
Jan VELÍŠEK, Karel CEJPEK
Czech J. Food Sci., 2011, 29(2):87-102 | DOI: 10.17221/524/2010-CJFS 
This review surveys the literature dealing with the structure of pigments produced by fungi of the phylum Basidiomycota and also covers their significant colourless precursors that are arranged according to their biochemical origin to the shikimate, polyketide and terpenoid derived compounds. The main groups of pigments and their leucoforms include simple benzoquinones, terphenylquinones, pulvinic acids, and derived products, anthraquinones, terpenoid quinones, benzotropolones, compounds of fatty acid origin and nitrogen-containing pigments (betalains and other alkaloids). Out of three orders proposed, the concern is only focused on the orders Agaricales...
Effect of buckwheat flour on microelements and proteins contents in gluten-free bread
Urszula Krupa-Kozak, Małgorzata Wronkowska, Maria Soral-Śmietana
Czech J. Food Sci., 2011, 29(2):103-108 | DOI: 10.17221/136/2010-CJFS
Coeliac disease is an autoimmune gluten-sensitive entheropathy. The only available treatment for it is the life-long adherence to a gluten-free diet although these products are often poor in proteins, minerals, and vitamins. The current study was designed to investigate the effect of buckwheat flour incorporation to a gluten-free experimental formulation on the size-related parameters, and microelements and proteins contents. Buckwheat flour affected positively the technological quality of bread, like bread specific volume index and loaf size. Increasing concentration of buckwheat flour (10-40%) in bread affected the proportional enrichment in proteins...
The effects of flour and protein preparations from amaranth and quinoa seeds on the rheological properties of wheat-flour dough and bread crumb
Sándor Tömösközi, Lilla Gyenge, Ágnes Pelcéder, Tibor Abonyi, Regine Schönlechner, Radomir Lásztity
Czech J. Food Sci., 2011, 29(2):109-116 | DOI: 10.17221/45/2010-CJFS
The effects of amaranth and quinoa flours and protein isolates prepared from amaranth and quinoa seeds on the rheological properties of wheat flour dough and bread were studied using new recording instruments, the micro Z-arm mixer (for dough) and the SMS-Texture analyser (for bread crumb). The addition of 10% amaranth or quinoa flours did not cause significant changes in rheological properties. However, higher additions (20% and 30%) resulted in significant changes in stability, the degree of softening and elasticity. Substitution of wheat flour by amaranth or quinoa flours resulted in an increase of water absorption capacity. A significant reduction...
Quality of winter wheat in relation to heat and drought shock after anthesis
Krisztina Balla, Mariann Rakszegi, Zhongy Li, Ferenc Békés, Szilvia Bencze, Ottó Veisz
Czech J. Food Sci., 2011, 29(2):117-128 | DOI: 10.17221/227/2010-CJFS
Raw material quality, which is influenced not only by the protein content, insoluble protein polymers, and glutenin-to-gliadin ratio but also by the starch granule size, is very important for the quality of bakery products. This study investigated the effect of high temperature and drought (during grain-filling) on the quality and components yield of five winter wheat varieties. Drought and drought + heat were found to have a much greater influence on the yield and quality than heat stress alone. Averaged over the varieties, the yield losses were 57% after drought, 76% after drought + heat, and only 31% after heat stresses. The reductions in the unextractable...
Physicochemical properties of soy protein isolates-acacia gum conjugates
Lixia Mu, Haifeng Zhao, Mouming Zhao, Chun Cui, Liya Liu
Czech J. Food Sci., 2011, 29(2):129-136 | DOI: 10.17221/339/2009-CJFS
Protein-polysaccharide conjugates were generally prepared by dry-heating. However, it was time-consuming and the sample gained was inhomogeneous. A faster way of preparing protein-polysaccharide conjugates is needed. Accordingly, soy protein isolates (SPI)-Acacia gum (GA) conjugates prepared by the wet-heating method were studied in the present work. Physicochemical properties of SPI-GA conjugates were also determined. The results showed that the wet-heating method could improve the rate of the graft reaction of protein and polysaccharide. The solubility of SPI-GA conjugates was significantly (P < 0.05) higher than that of unreacted SPI-GA...
Effect of storage on texture and microbiological stability of o-w emulsions with inulin
Paweł Glibowski, Monika Kordowska-Wiater, Agnieszka Glibowska
Czech J. Food Sci., 2011, 29(2):137-144 | DOI: 10.17221/213/2009-CJFS
The aim of this study was to characterise the effect of storage at 8°C on the texture and microbiological stability of oil-in-water solid emulsions containing inulin (20% w/w) and rapeseed oil (20% w/w). The samples were analysed within 24 h from the production and after 7, 14, 28, 42, and 56 days of storage. Whey protein isolate (3% w/w) or polyglycerol polyricinoleate (1% w/w) were used as emulsifiers and half of the samples were chemically preserved with potassium sorbate (0.2% w/w). Hardness, adhesiveness, and cohesiveness did not change significantly (p≤ 0.05) during storage. Most of the samples were microbiologically stable. Only...
Fatty acids, tocopherol, and sterol contents of some Nigella species seed oil
Bertrand Matthaus, Mehmet Musa Özcan
Czech J. Food Sci., 2011, 29(2):145-150 | DOI: 10.17221/206/2008-CJFS
The lipid compositions of the seed oils of some Nigella species were investigated. The total oil content of the seeds ranged from 28.0 to 36.4%. GC-MS fatty acid compositional analysis of the Nigella seed oils revealed the content of linoleic acid to be the highest (40.3-58.9%). Other prominent fatty acids were as follows: oleic (18.7-28.1%), palmitic (10.1-12.5%), 22:1 D11 (3.2-3.8%) and stearic (2.6-3.1%) acids. All the Nigella seed oils analysed exhibited differences in their tocopherol contents and the differences were estimated. The oils extracted from the seeds contained between 1.70-4.12 mg/100 g α-T, 0.97-4.51 mg/100...
HS-SPME/GC/MS profiles of convectively and microwave roasted Ivory Coast Robusta coffee brews
Grażyna Budryn, Ewa Nebesny, Józef Kula, Teresa Majda, Wiesława Krysiak
Czech J. Food Sci., 2011, 29(2):151-160 | DOI: 10.17221/69/2009-CJFS
Robusta coffee beans were convectively, microwave, and convectively-microwave heated at 230°C, 700 W, and 230°C/700 W (coupled heating), respectively, over periods of time ensuring the optimum sensory properties of the brews. HS-SPME/GC/MS analysis of the emissions from brews of the roasted coffee beans revealed 119 compounds. The highest total content of volatile substances was found in the brews prepared from convectively-microwave roasted coffee beans but the microwave roasting resulted in the most acceptable sensory properties of the brew aroma, presumably because of the lowest concentrations of the burnt note imparting compounds.
Evaluation of apricot fruit quality and correlations between physical and chemical attributes
Evica Mratinić, Bojan Popovski, Tomo Milošević, Melpomena Popovska
Czech J. Food Sci., 2011, 29(2):161-170 | DOI: 10.17221/203/2010-CJFS
The fruit of apricot (Prunus armeniaca L., Rosaceae) has been used as food in FYR Macedonia since a long time ago. The chemical organic matters from the fruit is a kind material for food processing and has potential nutritional, medical and commercial values. The results based on fruit physical and chemical analyses clearly showed that different apricot genotypes have very important contents of soluble solids, individual sugars, and titratable acidity in limited soil and climatic conditions. In addition, the contents of these chemical compounds in some genotypes were higher than those in the control cultivar Hungarian Best. Using the PC analysis...
Composition analysis and structural identification of anthocyanins in fruit of waxberry
Chuan-guang Qin, Yang Li, Weining Niu, Yan Ding, Xiaoya Shang, Chunlan Xu
Czech J. Food Sci., 2011, 29(2):171-180 | DOI: 10.17221/177/2010-CJFS
Anthocyanin pigments in the fruit of waxberry (Myrica rubra Sieb. et Zucc.), were extracted with 0.1% HCl in ethanol, and the crude anthocyanin extract was purified by C18 Sep-Pak cartridge open-column chromatography. High-performance liquid chromatography (HPLC) with photodiode array detection (PAD) and matrix-assisted laser desorption/ionisation-time of flight-mass spectrometry (MALDI-TOF-MS) was applied for the separation and identification of anthocyanins in the fruit of waxberry and their aglycones resulting from acid hydrolysis. Three anthocyanins were found in the fruit of waxberry and identified as Cyanidin 3-O-β-galacopyranoside...
Antioxidant capacity and antioxidants of strawberry, blackberry, and raspberry leaves
Lucie Buřičová, Mirjana Andjelkovic, Anna Čermáková, Zuzana Réblová, Ondřej Jurček, Erkki Kolehmainen, Roland Verhé, František Kvasnička6
Czech J. Food Sci., 2011, 29(2):181-189 | DOI: 10.17221/300/2010-CJFS
The total phenolic content (Folin-Ciocalteu method), free radical scavenging ability expressed as DPPH value, ferric reducing antioxidant capacity (FRAP), and oxygen radical absorbance capacity (ORAC) were determined in water extracts of leaves from Rosaceae family plants (Fragaria vesca L., Rubus fructicosus L., and Rubus idaeus L.). The antioxidant capacities of the extracts (in the order of the above mentioned methods) were 73.6-88.9%, 60.1-71.4%, 49.7-78.0% respectively, and 45.3-66.5% of that of green tea water extract. Further, the presence of 15 compounds (gallic acid, rutin, ellagic acid, caffeic acid, p-coumaric...
Deallergisation trials of pure celery juice and apple-celery juice mixture by oxidation
Pavla Novotná, Ivana Šetinová, Martina Heroldová, Milena Kmínková, Jiřina Průchová, Jan Strohalm, Vlasta Fiedlerová, Renata Winterová, Petr Kučera, Milan Houška
Czech J. Food Sci., 2011, 29(2):190-200 | DOI: 10.17221/273/2010-CJFS
This work aimed to determine if it was possible to eliminate or reduce the content of the Api g1 allergen in celery juice by oxidation, utilising its natural polyphenol oxidase (PPO) content. We attempted to determine a possible relationship between the enzymatic browning of celery juice and the reactivity of the Api g1 allergen. Pressed celery juice was stirred, and samples for the colour measurement and allergenicity, determined using the Western Blot (WB) method, were collected at pre-defined times. Oxidation failed to eliminate the allergenicity of pure celery juice. Further trials were focused on celery allergen elimination in apple-celery juices...
Prof. Ing. Jan Velíšek, DrSc., Chairman of our Journal celebrates his 65th birthday anniversary
J. Davídek
Czech J. Food Sci., 2011, 29(2):201-202 | DOI: 10.17221/116/2011-CJFS