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Publisher: Springer-Verlag   (Total: 2209 journals)

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e & i Elektrotechnik und Informationstechnik     Hybrid Journal   (Followers: 8, SJR: 0.146, h-index: 8)
e-Neuroforum     Hybrid Journal  
Early Childhood Education J.     Hybrid Journal   (Followers: 12, SJR: 0.367, h-index: 12)
Earth Science Informatics     Hybrid Journal   (Followers: 3, SJR: 0.245, h-index: 5)
Earth, Moon, and Planets     Hybrid Journal   (Followers: 5, SJR: 0.436, h-index: 28)
Earthquake Engineering and Engineering Vibration     Hybrid Journal   (Followers: 7, SJR: 0.433, h-index: 17)
Earthquake Science     Hybrid Journal   (Followers: 9, SJR: 0.486, h-index: 7)
East Asia     Hybrid Journal   (Followers: 7, SJR: 0.165, h-index: 9)
Eating and Weight Disorders - Studies on Anorexia, Bulimia and Obesity     Hybrid Journal   (Followers: 6, SJR: 0.289, h-index: 23)
EcoHealth     Hybrid Journal   (Followers: 1, SJR: 0.651, h-index: 22)
Ecological Research     Hybrid Journal   (Followers: 7, SJR: 0.698, h-index: 38)
Economic Botany     Hybrid Journal   (Followers: 8, SJR: 0.666, h-index: 40)
Economic Bulletin     Hybrid Journal   (Followers: 4)
Economic Change and Restructuring     Hybrid Journal   (Followers: 1, SJR: 0.263, h-index: 6)
Economic Theory     Hybrid Journal   (Followers: 5, SJR: 1.857, h-index: 31)
Economic Theory Bulletin     Hybrid Journal  
Economics of Governance     Hybrid Journal   (Followers: 2, SJR: 0.367, h-index: 12)
Ecosystems     Hybrid Journal   (Followers: 19, SJR: 1.793, h-index: 83)
Ecotoxicology     Hybrid Journal   (Followers: 10, SJR: 1.041, h-index: 53)
Education and Information Technologies     Hybrid Journal   (Followers: 151, SJR: 0.207, h-index: 15)
Educational Assessment, Evaluation and Accountability     Hybrid Journal   (Followers: 13, SJR: 0.519, h-index: 14)
Educational Psychology Review     Hybrid Journal   (Followers: 14, SJR: 1.781, h-index: 52)
Educational Research for Policy and Practice     Hybrid Journal   (Followers: 6, SJR: 0.211, h-index: 8)
Educational Studies in Mathematics     Hybrid Journal   (Followers: 8, SJR: 0.946, h-index: 27)
Educational Technology Research and Development     Partially Free   (Followers: 163, SJR: 1.124, h-index: 45)
Electrical Engineering     Hybrid Journal   (Followers: 9, SJR: 0.352, h-index: 17)
Electrocatalysis     Hybrid Journal   (SJR: 0.542, h-index: 7)
Electronic Commerce Research     Hybrid Journal   (Followers: 3, SJR: 0.636, h-index: 14)
Electronic Markets     Hybrid Journal   (Followers: 5, SJR: 0.326, h-index: 5)
Electronic Materials Letters     Hybrid Journal   (Followers: 2, SJR: 0.566, h-index: 11)
Elemente der Mathematik     Hybrid Journal  
Emergency Radiology     Hybrid Journal   (Followers: 4, SJR: 0.446, h-index: 22)
Empirica     Hybrid Journal   (Followers: 3, SJR: 0.185, h-index: 12)
Empirical Economics     Hybrid Journal   (Followers: 7, SJR: 0.5, h-index: 29)
Empirical Software Engineering     Hybrid Journal   (Followers: 4, SJR: 2.319, h-index: 33)
Employee Responsibilities and Rights J.     Hybrid Journal   (Followers: 2, SJR: 0.21, h-index: 13)
Endocrine     Hybrid Journal   (Followers: 4, SJR: 0.659, h-index: 55)
Endocrine Pathology     Hybrid Journal   (Followers: 2, SJR: 0.555, h-index: 27)
Energy Efficiency     Hybrid Journal   (Followers: 11, SJR: 1.056, h-index: 10)
Energy Systems     Hybrid Journal   (Followers: 9, SJR: 0.589, h-index: 5)
Engineering With Computers     Hybrid Journal   (Followers: 5, SJR: 0.497, h-index: 26)
Entomological Review     Hybrid Journal   (Followers: 3, SJR: 0.128, h-index: 5)
Environment Systems & Decisions     Hybrid Journal   (Followers: 2)
Environment, Development and Sustainability     Hybrid Journal   (Followers: 28, SJR: 0.319, h-index: 26)
Environmental and Ecological Statistics     Hybrid Journal   (Followers: 5, SJR: 0.389, h-index: 29)
Environmental and Resource Economics     Hybrid Journal   (Followers: 17, SJR: 1.651, h-index: 46)
Environmental Biology of Fishes     Hybrid Journal   (Followers: 3, SJR: 0.486, h-index: 53)
Environmental Chemistry Letters     Hybrid Journal   (Followers: 3, SJR: 0.664, h-index: 22)
Environmental Earth Sciences     Hybrid Journal   (Followers: 10, SJR: 0.601, h-index: 55)
Environmental Economics and Policy Studies     Hybrid Journal   (Followers: 6, SJR: 0.35, h-index: 3)
Environmental Evidence     Open Access  
Environmental Fluid Mechanics     Hybrid Journal   (Followers: 2, SJR: 0.732, h-index: 23)
Environmental Geochemistry and Health     Hybrid Journal   (Followers: 2, SJR: 0.909, h-index: 32)
Environmental Geology     Hybrid Journal   (Followers: 11)
Environmental Health and Preventive Medicine     Hybrid Journal   (Followers: 2, SJR: 0.388, h-index: 14)
Environmental Management     Hybrid Journal   (Followers: 31, SJR: 0.773, h-index: 60)
Environmental Modeling & Assessment     Hybrid Journal   (Followers: 11, SJR: 0.413, h-index: 27)
Environmental Monitoring and Assessment     Hybrid Journal   (Followers: 9, SJR: 0.671, h-index: 46)
Environmental Science and Pollution Research     Hybrid Journal   (Followers: 11, SJR: 0.878, h-index: 42)
Epidemiologic Perspectives & Innovations     Open Access   (Followers: 1, SJR: 1.002, h-index: 14)
Epileptic Disorders     Hybrid Journal   (Followers: 1, SJR: 0.669, h-index: 34)
EPJ A - Hadrons and Nuclei     Hybrid Journal   (Followers: 1, SJR: 1.435, h-index: 58)
EPJ B - Condensed Matter and Complex Systems     Hybrid Journal   (Followers: 3, SJR: 0.749, h-index: 85)
EPJ direct     Hybrid Journal  
EPJ E - Soft Matter and Biological Physics     Hybrid Journal   (Followers: 1, SJR: 0.661, h-index: 57)
EPMA J.     Open Access   (SJR: 0.161, h-index: 4)
ERA-Forum     Hybrid Journal   (Followers: 2, SJR: 0.13, h-index: 2)
Erkenntnis     Hybrid Journal   (Followers: 11, SJR: 0.62, h-index: 14)
Erwerbs-Obstbau     Hybrid Journal   (SJR: 0.173, h-index: 8)
Esophagus     Hybrid Journal   (SJR: 0.268, h-index: 9)
Estuaries and Coasts     Hybrid Journal   (Followers: 3, SJR: 1.111, h-index: 61)
Ethical Theory and Moral Practice     Hybrid Journal   (Followers: 7, SJR: 0.278, h-index: 8)
Ethics and Information Technology     Hybrid Journal   (Followers: 164, SJR: 0.363, h-index: 20)
Ethik in der Medizin     Hybrid Journal   (SJR: 0.204, h-index: 6)
Euphytica     Hybrid Journal   (Followers: 7, SJR: 0.709, h-index: 57)
Eurasian Soil Science     Hybrid Journal   (Followers: 2, SJR: 0.271, h-index: 10)
EURO J. of Transportation and Logistics     Hybrid Journal   (Followers: 4)
EURO J. on Computational Optimization     Hybrid Journal  
EURO J. on Decision Processes     Hybrid Journal  
Europaisches J. fur Minderheitenfragen     Hybrid Journal  
European Actuarial J.     Hybrid Journal   (Followers: 3)
European Archives of Oto-Rhino-Laryngology     Hybrid Journal   (Followers: 4, SJR: 0.737, h-index: 37)
European Archives of Paediatric Dentistry     Hybrid Journal   (Followers: 1, SJR: 0.446, h-index: 12)
European Archives of Psychiatry and Clinical Neuroscience     Hybrid Journal   (Followers: 2, SJR: 1.334, h-index: 62)
European Biophysics J.     Hybrid Journal   (Followers: 4, SJR: 0.979, h-index: 53)
European Child & Adolescent Psychiatry     Hybrid Journal   (Followers: 4, SJR: 1.269, h-index: 51)
European Clinics in Obstetrics and Gynaecology     Hybrid Journal   (Followers: 4)
European Food Research and Technology     Hybrid Journal   (Followers: 8, SJR: 0.773, h-index: 49)
European J. for Education Law and Policy     Hybrid Journal   (Followers: 5)
European J. for Philosophy of Science     Partially Free   (Followers: 4, SJR: 0.165, h-index: 2)
European J. of Ageing     Hybrid Journal   (Followers: 8, SJR: 0.49, h-index: 17)
European J. of Applied Physiology     Hybrid Journal   (Followers: 7, SJR: 1.044, h-index: 74)
European J. of Clinical Microbiology & Infectious Diseases     Hybrid Journal   (Followers: 10, SJR: 0.958, h-index: 74)
European J. of Clinical Pharmacology     Hybrid Journal   (Followers: 9, SJR: 0.916, h-index: 69)
European J. of Dermatology     Hybrid Journal   (Followers: 7)
European J. of Drug Metabolism and Pharmacokinetics     Hybrid Journal   (Followers: 6, SJR: 0.24, h-index: 25)
European J. of Epidemiology     Hybrid Journal   (Followers: 17, SJR: 1.946, h-index: 60)
European J. of Forest Research     Hybrid Journal   (Followers: 3, SJR: 0.864, h-index: 25)
European J. of Health Economics     Hybrid Journal   (Followers: 11, SJR: 0.67, h-index: 25)
European J. of Law and Economics     Hybrid Journal   (Followers: 168, SJR: 0.242, h-index: 13)

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Journal Cover European Food Research and Technology
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   Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 1438-2377 - ISSN (Online) 1438-2385
     Published by Springer-Verlag Homepage  [2209 journals]   [SJR: 0.773]   [H-I: 49]
  • Relationship between        class="a-plus-plus">N-nitrosodiethylamine
           formation and protein oxidation in pork protein extracts
    • Abstract: Abstract The relationship between protein oxidation and N-nitrosodiethylamine (NDEA) formation was assessed. Packaged fresh minced pork was stored at 2 ± 1 °C for 0, 4, 7, and 10 days. Myofibrillar protein (MP), sarcoplasmic protein (SP), and muscle homogenate were obtained from the stored minced pork and allowed to react with sodium nitrite at 80 °C for 1 h. The relationship between NDEA formation and indexes of protein oxidation was assessed by principal component analysis. The formation of NDEA in meat was correlated with protein and lipid oxidation. Lipid oxidation promoted the formation of NDEA and was positively correlated with protein oxidation. Carbonyl compounds from oxidized MP and free amines from dissociated SP promoted NDEA formation. Therefore, the effect of protein oxidation on NDEA formation depends on the type of protein and its oxidation products.
      PubDate: 2014-10-01
       
  • Reverse osmosis and nanofiltration membranes for the improvement of must
           quality
    • Abstract: Abstract When the vintage is poor, different must concentration techniques are used for overcoming grape compositional deficiency, such as evaporative or freeze concentration, and membrane processes. The membrane filtration works at low temperature, preserving must components from degradation. The aim of the present work was to tailor reverse osmosis and nanofiltration technologies applied to grape juice testing several membranes for different grape varieties from southern Italy. The main oenological parameters, including sugar content, acidity, pH, color and total phenol content, were evaluated in comparison with the addition of rectified concentrated must. Quality characteristics of all musts showed to be improved by means of membrane processes, which could be successfully implemented in the cases of premature harvest carried out for obtaining wines with enhanced acidity.
      PubDate: 2014-10-01
       
  • Analytical characterisation of the seeds of two tomato varieties as a
           basis for recycling of waste materials in the food industry
    • Abstract: Abstract The tomato processing industry generates annually high amounts of waste. In respect of a possible recycling of these materials, the seeds of the two tomato varieties Waltinger and Red Currant were analysed. Contents of carotenoids and vitamin E were determined by HPLC. The antioxidant capacity was analysed by several assays (Folin–Ciocalteu, TEAC, ORAC), whereby hydrophilic and lipophilic compounds were gathered separately. The fatty acid profile was determined by gas chromatography. The seeds contained only little amounts of (all-E)-lutein and (all-E)-zeaxanthin. Vitamin E content of Waltinger seeds was nearly twice as high as that of Red Currant seeds with γ-tocopherol as the main vitamer. Red Currant seeds showed always higher antioxidant capacity. Hydrophilic extracts contributed mainly to the total antioxidant capacity. The oil of the seeds was rich in unsaturated fatty acids, especially in linoleic acid. Finally, the results showed that tomato seeds contain some important substances. So concerning waste management, they can serve as a secondary raw material for new products such as edible oil.
      PubDate: 2014-10-01
       
  • Physicochemical characterization of Pommeau de Normandie: establishing a
           relationship between metal contents and turbidity of the Pommeau samples
    • Abstract: Abstract Pommeau is a traditional beverage of France which is elaborated by mixing Calvados and clarified apple must. In this study, this beverage was physicochemically characterized for the first time by different analytical methods. Pommeau contains a mean content of ethanol around 16.3 % (v/v) while pH values are observed between 3.9 and 4.3. Total and volatile acidities are rather low if they are compared to other beverages, and this is correlated with relatively low quantities of malic acid (around 1.5 g/L) and high concentrations of reducing sugars (79–109 g/L). Alkali and alkaline earth metals (K, Na, Ca and Mg) are dominant in concentration as compared to the other metals. Pommeau is a sweet beverage which reflects that producers are selecting higher proportions of sweet apples and lower proportions of acidic apples. The concentration of metals may be correlated to the turbidities of Pommeau samples up to some extent. The statistical analyses have shown the association of metals with more turbid sample.
      PubDate: 2014-10-01
       
  • Production and optimization of monacolin K by citrinin-free        class="a-plus-plus">Monascus pilosus MS-1 in
           solid-state fermentation using non-glutinous rice and soybean flours as
           substrate
    • Abstract: Abstract Monacolin K (MK) acts as a natural inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase. Red fermented rice by Monascus spp. which is rich in MK can be used as dietary supplement to reduce the serum triglyceride and total cholesterol. A Monascus pilosus MS-1 with high-producing MK but free of citrinin had been screened in our previous investigation. Here, its solid-state fermentation parameters were optimized using statistical methods to maximize MK yield when non-glutinous rice and soybean flours were used as substrate. Maximum MK yield (17.662 mg/g) was predicted when 55 g dry substrate (20 sieve mesh), including 60 % non-glutinous rice flour and 40 % soybean flour, was put into a 250-mL conical flask, and the contents of water, acetic acid and MgSO4·7H2O were adjusted to 35 %, 0.6 % (v/w) and 0.004 mol/kg, respectively. Then, the substrate was mixed and sterilized, and scattered before cooling. Later, 13 % (v/w) inoculum pre-cultured for 36 h at 30 °C was used, then incubated at 30 °C for 60 h and followed by a further incubation at 24 °C up to 14 days. The verified MK yield was 18.733 mg/g, which was 106.06 % to the predicted MK yield. The MK yield was enhanced to 33 times after optimization. No citrinin was detected in Monascus pilosus MS-1 fermented products. These results indicate that citrinin-free MK can be produced under the optimized conditions.
      PubDate: 2014-10-01
       
  • Two quantitative multiplex real-time PCR systems for the efficient GMO
           screening of food products
    • Abstract: Abstract According to the EU and Swiss food legislation, only deregulated traits of transgenic plants are allowed to be imported and sold to the consumer. In order to control imports of soya and maize products from retailers, efficient and reliable methods for the detection and quantification are a prerequisite. The screening for specific DNA elements characteristic of transgenic plants is crucial for further analysis and has a major impact on the efficiency of the whole analysis workflow. To allow laboratories to efficiently and reliably screen food products for transgenic plant products, two novel multiplex real-time polymerase chain reaction (PCR) systems were developed and validated. One system determines DNA contents from maize, soya, cauliflower mosaic virus (CaMV) 35S promoter (P35S), NOS terminator from Agrobacterium tumefaciens and CaMV, and the second PCR system simultaneously detects DNA sequences from figwort mosaic virus promoter (PFMV), from bar gene of Streptomyces hygroscopicus, from gene coding for phosphinothricin acetyltransferase (PAT) and from a DNA construct of enolpyruvyl shikimate phosphate synthase gene (CP4-EPSPS) and Arabidopsis thaliana (CPT2). The tests exhibit good specificity and a limit of detection of at least 0.1 % for all analytes.
      PubDate: 2014-10-01
       
  • Liquid food pasteurization by pulsed electric fields: dimensionless
           analysis via Sherwood number for a comprehensive understanding
    • Abstract: Abstract Pasteurization of liquid foods by pulsed electric fields has been a subject of research for many years. The biological membranes are damaged by the process of electroporation, allowing leakage of internal compounds and possibly leading to subsequent cell lysis. This work is a continuation and extension of a former study that correlated biological inactivation with a modified Sherwood number. The Sherwood number is normally used to describe mass transfer under an electromotive force. In the present work, the Sherwood model was modified; the electric field intensity E was replaced by the specific energy W specif a more general parameter, particularly when the chamber design results in a non-constant electric field. To deal with particular parameters, the length of the treatment chamber was also introduced. Experimental results were compared with the results obtained via the new model we propose. In addition, the model was able to satisfactorily describe results previously published in the literature. The model proposed is thus suitable for describing microbial inactivation in various systems, according to the chamber geometry, hydraulic regimes, electric signal shapes and durations, and the types of microorganisms (yeast and rod bacteria).
      PubDate: 2014-10-01
       
  • Antibacterial/antifungal activity and synergistic interactions between
           C70–C       class="a-plus-plus">120 polyprenol homologs from
           Ginkgo Biloba L. leaves
           and the corresponding synthetic derivatives
    • Abstract: Abstract Polyprenol (GBP) separated from Ginkgo biloba L. leaves (GBL) is an important lipid component having many bioactive effects. The five GBP derivatives, polyprenyl acetate, n-amyl polypentylene, polyprenyl-3-isoamyl benzyl ether, polyprenyl dichlorophosphite (GPD) and polyprenyl phosphate disodium salt (GPP), were synthetized from GBP homologs (C70–C120), isolated and purified from GBL. This study provides the new evidence of the antibacterial/antifungal activities and synergistic effect on GBP with the five GBP derivatives against five pathogenic strains (Salmonella enterica, Staphylocococus aureus, Aspergillus niger, Escherichia coli and Bacillus subtilis). As a result, GPD showed the highest activity among all the tested samples and inhibited the growth of all the strains. And the GPP and GBP mixture group had the strongest synergistic effect against S. enterica among all mixture groups against the five tested strains, and the fractional inhibitory concentration index was 0.37. The proportion of GPP and GBP was 37.41:62.59 % (wt/wt) that was determined as the optimal proportion of synergistic effect on GPP with GBP against S. enterica. It infers that the antibacterial/antifungal activities and synergistic effect on alkyl-substituted GBP derivative with GBP are decreased, while the effect of phosphate-substituted GBP derivative with GBP is increased. The author assumes that antibacterial/antifungal activity of polyprenols and their derivatives is maybe a connection between increased membrane destabilization and increased polyprenol length, and polyprenols compared with their derivatives have different arrangement to the membrane surface of microorganisms. This study provides a new scientific basis for the ethnomedical use of GBP and GBP derivatives against bacterial and fungal diseases of animals and plants.
      PubDate: 2014-10-01
       
  • 1-Methylcyclopropene postharvest treatment and their effect on apple
           quality during long-term storage time
    • Abstract: Abstract The aim of this study was to evaluate the effect of the postharvest treatment by 1-methylcyclopropene (1-MCP) and storage time on the apple physicochemically quality. The effects of apple storage during 6 months on basic parameters such as dry weight, total soluble solids and titratable acidity, composition of phenolics, antioxidant activity and sensory evaluation were studied to evaluate the potential applicability of long-time stored apples for consumption and processing. Long-time storage of apples resulted in a higher dry matter but decreases total soluble solids and titratable acidity in all examined cultivars (cv.) of apples. The total phenolics determined by HPLC in fresh apples ranged from 1,243 mg in ‘Idared’ cv. to 1,435 mg/kg in ‘Shampion’ cv. During storage, the decrease of polyphenolic content has been observed, in ‘Shampion’ cv., it was higher than in ‘Idared’ cv. Similar effects were observed for antioxidant activity. Comparing quality of fruits just after harvest, it was found that cultivar affects most of the investigated sensory attributes with the exception of ripe apple smell, crispness, crunchiness and the overall texture score. In general, ‘Shampion’ cv. apples got higher ranks for sweetness, taste and the overall quality, whereas ‘Idared’ cv. were perceived as sourer, which is in arrangement with instrumental measurements. The results of presented study demonstrate that apples after storage, especially ‘Shampion’ cv., can be a valuable sensory attributes for food product and consumption. This study indicates that the use of 1-MCP treatment in long-term storage of apples is promising for maintaining the eating quality of fruits, however, in some extent may affect their antioxidant compounds content.
      PubDate: 2014-10-01
       
  • Simultaneous detection of allergenic fish, cephalopods and shellfish in
           food by multiplex ligation-dependent probe amplification
    • Abstract: Abstract People suffering from food allergy rely on correct food labelling as the ingestion of minimal amounts of the respective allergen can trigger severe allergenic reactions. Probes for the detection of DNA from allergenic fish, shellfish and cephalopod species in food using multiplex ligation-dependent probe amplification were developed. The specificity and the sensitivity of the detection system were investigated. The limit of detection was 20 mg kg−1 for scallop, fish and bivalve species and 100 mg kg−1 for cephalopod, gastropod and crustacean species using self-prepared sushi spiked with the analytes in different concentration levels. The analysis of 10 commercial food samples demonstrates the applicability of the developed method and its suitability for food quality control. Therefore, the method can be used to monitor the compliance with labelling rules regarding food allergens.
      PubDate: 2014-10-01
       
  • Investigation of antibrowning activity of pine needle (       class="a-plus-plus">Cedrus deodara) extract with
           fresh-cut apple slice model and identification of the primary active
           components
    • Abstract: Abstract Cedrus deodara is a large evergreen tree of the family Pinaceae and widely distributed to the west of Himalayas. Its pine needles are consumed as a traditional food and perceived as a valuable source for bioactive compounds. A recent study has demonstrated Cedrus deodara pine needle extract (CDE) can inactivate tyrosinase. However, possible action mechanism and application of the extract have not been elucidated. In the present study, the application of CDE in food industry was explored using a fresh-cut apple slice model. Through evaluating the variation in a*, b* and L* values, the browning extent of apple slices was found to be inhibited by CDE. Moreover, in order to explore the antibrowning mechanism, we investigated the antioxidant and antibrowning capacities, total phenolic and flavonoid contents and the major bioactive constituents of the extract. It was found CDE showed strong antioxidant activity to scavenge ABTS (SC50, 24.33 μg/mL) and DPPH (SC50, 35.94 μg/mL) radicals, inhibited monophenolase (IC50, 0.76 ± 0.08 mg/mL) and diphenolase (IC50, 1.01 ± 0.09 mg/mL) activities and contained high content of phenolics (76.39 ± 2.27 mg gallic acid equivalent/g extract) and flavonoids (33.23 ± 3.25 mg rutin equivalent/g extract). Furthermore, according to the bioassay-guided isolation and the analysis of high-performance liquid chromatography–mass spectrometry and nuclear magnetic resonance, methylconiferin and ferulic acid-β-d-glucoside were determined to be the main active compounds. The current results provided the possible antibrowning mechanism of CDE and confirmed C. deodara pine needles might be a natural resource for preparing antibrowning agents of vegetables and fruits in food industry.
      PubDate: 2014-10-01
       
  • Use of highly variable gene (yycH) as DNA marker to resolve interspecific
           relationships within the        class="a-plus-plus">Lactobacillus casei group and
           a target for developing novel species-specific PCR primers
    • Abstract: Abstract Identifying Lactobacillus species group using only phenotypic and genotypic (16S rDNA sequence homology analysis) techniques yields inaccurate results. In this study, the partial yycH gene sequence was used for species discrimination by direct DNA sequencing and as target in a species-specific PCR assay. All examined Lactobacillus strains were clearly distinguished from the closely related species by comparative sequence analysis of the yycH gene. The average sequence similarity for the yycH gene (78.5 %) among type strains was significantly lower than that of the 16S rRNA sequence (99.0 %). Therefore, the yycH gene can be proposed as an additional molecular marker for Lactobacillus casei group that provides higher resolution than 16S rRNA. In addition, the species-specific primers were also developed based on the yycH gene sequences, which were then employed for PCR using the template DNA of Lactobacter strains. The PCR primer pairs were shown to be specific for Lactobacillus paracasei and Lactobacillus rhamnosus. Our data indicate that the phylogenetic relationships in the L. casei group are easily resolved by direct sequencing of the yycH gene and combined with species-specific PCR assays.
      PubDate: 2014-10-01
       
  • In vitro activity of the Brazil nut (       class="a-plus-plus">Bertholletia excelsa H.B.K.)
           oil in aflatoxigenic strains of        class="a-plus-plus">Aspergillus parasiticus
    • Abstract: Abstract The growing demand for safe foods without preservatives has fostered research to investigate the effects of natural compounds on microorganisms. Accordingly, an in vitro study was carried out to determine physico-chemical characterization and investigate the antimicrobial effects of Brazil nut oil on toxigenic strains of Aspergillus. The antifungal activity testing was carried out isolating A. parasiticus by transferring the strains to the center of the plates containing treatments with different concentrations of Brazil nut oil. The plates were incubated for 8 days at 28 °C with subsequent extraction of toxins. The aflatoxins AFB1 AFB2, AFG1, and AFG2 were determined by thin-layer chromatography. The values found for acidity, refractive index, and density ranged from 0.3512 to 0.7092, 1.4670 to 1.470, and 9.2 × 102 to 16.7 × 102, respectively. The results obtained showed that the effect of Brazil nut oil on the growth diameter of the fungal colony was time and concentration dependent. After 8 days of incubation, all treatments showed better fungal growth inhibition compared with that of the control. Total inhibition of aflatoxin production by the strain (LOQ of the method: 2 g/kg) was also observed in the medium containing the oil, while in the control treatment, AFB1, AFB2, and AFG1 were produced by the inoculated strain A. parasiticus.
      PubDate: 2014-10-01
       
  • Amylolytic activities and starch reserve mobilization during the
           germination of quinoa
    • Abstract: Abstract Quinoa (Chenopodium quinoa) is a dicotyledonous plant producing perispermic seeds that is increasingly popular in the Western world due to its nutritional value. Germination can be used in food processing to alter the sensory, nutritional and functional properties of grains, and the increased enzyme activities may have beneficial influences in food applications. Knowledge about the germination of perispermic seeds is scarce. In this study, the development of amylolytic activities and subsequent changes in sugar profiles and starch content were followed in quinoa over a period of 72 h. The seeds germinated rapidly with radicle protrusion occurring 8 h after imbibition, when the seeds had reached a moisture content of 44 %. A low level of α-amylase activity (determined at pH 5.2 using blocked ρ-nitrophenyl-maltoheptaoside as substrate) was present in the embryo of non-germinating seeds, but emerged in the perisperm only after 24 h, followed by a sharp increase in activity in both tissues. The accumulation of glucose and fructose (determined with high pressure liquid chromatography) and the decrease in starch content (determined with an enzymatic assay) were observed after 24 and 36 h, respectively, indicating the onset of starch reserve mobilization. Overall, the levels of amylolytic activities remained very low compared with traditional malting cereals, suggesting the unsuitability of quinoa as a source of amylases in food applications. Scanning electron microscopy, used to visualize changes in starch granule morphology, showed mainly exocorrosion, suggesting a homogenous structure of the outer layers of quinoa starch.
      PubDate: 2014-10-01
       
  • Enzymatic acylation of isoorientin isolated from antioxidant of bamboo
           leaves with palmitic acid and antiradical activity of the acylated
           derivatives
    • Abstract: Abstract The utilization of bamboo-leaf extracts is limited by their weak solubility in lipidic media. As such, this study established an effective and relatively cheap method for preparation of ester of isoorientin isolated from bamboo-leaf extracts. Acylation of isoorientin with palmitic acid was efficient in a system containing dried tert-amyl alcohol and molecular sieves, yielding from 22 to 90 % bioconversion with different conditions; in detail, several factors (the origin and the amount of the lipase, temperature and water content of the system) were investigated in depth with the effect on the performance of the acylation reaction in this paper. Thereafter high purity ester (95 %) was obtained following a two-step solvent purification procedure and a chromatographic separation. With 1H and 13C nuclear magnetic resonance spectroscopy analysis, single product was detected to be 6″-O-palmitate isoorientin ester. Introducing an acyl group into isoorientin significantly improved its lipophilicity yet slightly reduced their antioxidant activity.
      PubDate: 2014-10-01
       
  • Stability of casein antioxidant peptide fractions during in vitro
           digestion/Caco-2 cell model: characteristics of the resistant peptides
    • Abstract: Abstract Peptides with in vitro antioxidant activity have no direct reaction on in vivo organisms, because of gastrointestinal (GI) barriers in human tract. In this study, low-molecular-weight peptides of casein were acquired by hydrolysis with alcalase and isolation with Sephadex G-25 gel filtration. Each peptide fraction was performed on simulated GI digestion (stage I) and Caco-2 cell absorption (stage II) for evaluating GI stability, with molecular weight distribution, peptide nitrogen, trolox equivalent antioxidant capacity, and oxygen radical antioxidant capacity. The peptide fraction below 1,000 Da (F3) had shown weaker structural stability during stage I digestion, while it exerted excellent antioxidative stability in whole stages and finally produced the highest content of GI resistant peptides. Three resistant peptides, Ile-Glu, Ser-Asp-Lys, and Ala-Tyr-Pro-Ser, were characterized, and Ala-Tyr-Pro-Ser might strongly contribute to in vivo antioxidant activities. It is suggested that alcalase may promote the production of GI resistant peptides.
      PubDate: 2014-10-01
       
  • Changes of heat-treated soymilks in bioactive compounds and their
           antioxidant activities under in vitro gastrointestinal digestion
    • Abstract: Abstract To investigate the influence of in vitro gastrointestinal digestion on contents of bioactive compounds and antioxidant activities of heat-treated soymilks, changes of total phenolics content (TPC), total flavonoids content (TFC), content and profile of isoflavones, oxygen radical absorbance capacity (ORAC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric-reducing antioxidant power (FRAP) were assayed after different heat treatments (at 95 °C for 20, 40, 60 min; 121 °C for 3, 6, 9 min and 143 °C for 20, 40, 60 s respectively) and gastrointestinal digestion. Results showed that digestion significantly influenced the contents of bioactive compounds and antioxidant activities of soymilks. Increases of DPPH radical scavenging activity, FRAP and ORAC of the heat-treated soymilks after gastric digestion were consistent with the increases of TPC (110.68–152.60 %) and TFC (4.48–31.10 %). In the dialysate fractions as the absorbable and utilized part, it was found that TPC, TFC, isoflavones and antioxidant activities (DPPH radical scavenging activity, FRAP and ORAC) were significantly decreased as compared with the gastric digestion fractions and duodenal fractions. Analysis showed that the bioaccessibility of TPC reached 107.17–125.14 %, TFC reached 34.63–67.19 % and total isoflavones reached 34.40–41.22 %, respectively, indicating the rich bioaccessible compounds in soymilk. Daidzein and its derivates were proven as the most bioaccessible isoflavones (about 36.99–44.14 %). Glucoside isoflavones showed the highest bioaccessibilities followed by malonylglucosides, acetylglucosides and aglycones. Overall, the soymilks treated at 95 °C and 60 min and 121 °C and 9 min had higher bioactive compounds contents, antioxidant activities and bioaccessibilities in the dialysate fractions.
      PubDate: 2014-10-01
       
  • Quantitative analysis of 3-alkyl-2-methoxypyrazines in German Sauvignon
           blanc wines by MDGC–MS or MDGC–MS/MS for viticultural and
           enological studies
    • Abstract: Abstract A method for trace-level analysis of 3-alkyl-2-methoxypyrazines (MPs) based on mixed-bed cation-exchange solid phase extraction followed by heart-cut multidimensional gas chromatographic analysis was applied in a trial on viticultural and enological treatments of Sauvignon blanc wines produced in Germany. The quantification was based on a stable isotope dilution assay using deuterated MPs. For method comparison, detection was either with selected ion monitoring with a quadrupole mass spectrometer (MS) or after selected reaction monitoring using a triple quadrupole MS. Comparable performance for MP detection in the lower ng L−1 concentration range was found for both detection methods; however, in some cases, matrix problems could only be solved with MS/MS detection. It could be shown that MP levels varied considerably between the investigated vintages, with concentrations often well below 10 ng L−1. Leaf removal as a viticultural trial was a measure to decrease MP concentrations; however, the effects observed were low in the vintages studied here. Cold maceration and stem addition to the must were found as valuable enological means for increasing the MP concentration and improving the green sensory notes typical for cold climate Sauvignon blanc wines.
      PubDate: 2014-10-01
       
  • Authentication of raw and processed tuna from Indonesian markets using DNA
           barcoding, nuclear gene and character-based approach
    • Abstract: Abstract Establishing seafood authentication methods is an important task for fisheries research laboratories and food control authorities. Nowadays, the extent of fish species substitution is suspected being greater than ever before in commercial markets. In order to provide reliable polymerase chain reaction (PCR)-based authentication systems for tunas, we collected and analyzed authentic tuna reference samples and tuna-food products from Indonesian markets. Our analytical methods mainly relied on identification using the mitochondrial cytochrome c oxidase subunit I (COI) gene, as a genetic marker for “DNA barcoding,” as well as the rhodopsin (RH1) gene as a nuclear marker. Additionally, we identified species-specific nucleotide diagnostic positions (characters) to complete the results obtained basic local alignment search (BLAST) and phylogenetic analysis. Authentication results of tuna-food products showed relatively successful amplification for the COI gene; RH1 acted as an alternative solution for some of the samples, which had failed to react in COI-PCR. Species of the genus Thunnus could not be unambiguously differentiated by BLAST and phylogenetic analysis (neighbor-joining tree) in all cases due to the high similarity of the COI sequences. However, the character-based identification method was found to be helpful for species assignment in case of tuna-food products. Therefore, our findings demonstrated that the COI gene could be more reliable used as a tool for Indonesian commercial tuna products authentication, if the sequencing results were combined with the character-based identification using differences at certain nucleotide positions.
      PubDate: 2014-10-01
       
  • Biotechnological activities from yeasts isolated from olive oil mills
    • Abstract: Abstract The yeast biota associated to three eastern Spain oil mills has been evaluated. Each environment has associated a characteristic number and variability of yeasts. The D1/D2 rDNA sequencing protocol has been proved to be a useful method to identify 216 yeasts from oleic environments, showing us Candida (several species), Saccharomyces paradoxus, Citeromyces matritensis and Cryptococcus sp. as the most representative genera. Moreover, a further screening of biochemical activities has provided us with a collection of isolates able to metabolize different substrates. In particular, protease, β-glucosidase, pectinase, polygalacturonase, xylanase, lipase, esterase and catalase activities were investigated. The majority of the strains showed moderate or high β-glucosidase, lipase and pectinase activities, while protease and polygalacturonase activities are less frequent. In a second step, nutritional competition assays were carried out to investigate the antagonic effect of yeasts associated to olive oil mills with Aspergillus fungi. Yeasts can be an effective biocontrol tool as they can colonize olives and compete for space and nutrients with pathogenic fungi, avoiding the use of chemical fungicides.
      PubDate: 2014-09-26
       
 
 
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