Suchergebnisse

The antibiotics residual presence in honey is a current problem with negative implications, mainly commercial since according to European legislation antibiotic occurrence in honey samples is forbidden.

Honey is a natural sweet substance produced by Apis mellifera, which has great potential to serve as a natural food antioxidant. The physicochemical quality criteria of honey are well specified by the European Legislation (EC Directive 2001/110). The quality properties of honey can be diminished by the influence of heating. As an alternative to the conventional thermal pasteurization, nonthermal high pressure processing (HPP) has potential to produce safe food with similar characteristics to the raw unprocessed foods. The aim of this study was to investigate the effect of HPP (725 MPa for 10 minutes) and HPP with temperature (725 MPa for 10 minutes at 50 °C) on physicochemical properties (moisture, pH, electrical conductivity, free acidity, diastase activity and hydroxymethylfurfural content) of a heather honey in comparison with thermal treatment (75 °C for 5 minutes) and unprocessed honey. The effect of storage (6 months) in processed and unprocessed samples was also investigated. The results showed significant differences in some physicochemical parameters, for instance, the hydroxymethylfurfural content, an indicator of honeys' freshness that depends on several factors, such as temperature, time of heating and storage conditions. An electronic tongue (ET) with lipidic membranes was used to evaluate the differences between all honey groups. A linear discriminant analysis to the ET results showed that the processed and unprocessed honey samples at day 0 (when treatments were applied) and after the storage have matrix differences that allows a complete separation of groups. The correlation between physicochemical and electronic tongue data showed the advantages of this data fusion. ; info:eu-repo/semantics/publishedVersion

The present study aimed to characterize five commercial honeys available in the Portuguese market in respect to their floral origins, physicochemical parameters and microbial safety and commercial quality assessment. Pollen profile, colour, moisture content, ash, acidity, electrical conductivity, pH, reducing sugars, apparent sucrose and HMF were the parameters analysed in each honey sample. Aerobic mesophiles, moulds and yeasts, fecal coliforms and sulphite-reducing clostridia were the microbial contaminants of interest studied. The antimicrobial effect against four fermentative yeasts was determined. Concerning the physicochemical parameters, all honey samples were found to meet European Legislation (EC Directive 2001/110) for all parameters, except for HMF and apparent sucrose. Microbiologically, the commercial quality was considered good and all samples showed to be negative in respect to safety parameters. We also verified that the presence of honey differentially affected the growth of fermentative yeasts under study, depending on the type of yeast, but this growth was not significantly influenced by the type of honey used.

Olive oils may be commercially classified, in a decrease order of quality and economic value, as extra-virgin (EVOO), virgin (VOO) or lampante (LOO) olive oils, being quite prone to frauds. Thus legal protection regulations have been approved by the European Union Commission [1,2], being required the fulfilment of several physicochemical and sensory thresholds [3,4]. Unfortunately, the mixture of expensive olive oils with low quality oils aiming fraudulent economic revenue is still a common practice difficult to detect. In this work, a potentiometric electronic tongue (E-tongue) was used to detect adulteration of an EVOO with different added levels (2.5%, 5%, 10%, 20% and 40%; v/v) of an LOO with an intense sensory defect (rancid or wineyvinegary). Previously, similar electrochemical devices, also comprising lipid polymeric sensor membranes, showed to be able to give qualitative and/or quantitative responses towards basic taste sensations (acid, bitter, salty, sweet, and umami), positive sensory attributes (bitter, fruity, green and pungency) or defects (e.g., butyric, musty, putrid, winey-vinegary and zapateria) [5-8]. The E-tongue coupled with linear discriminant technique (based on the signal profiles of 19 or 20 E-tongue sensors, chosen using a simulated annealing meta-heuristic variable selection algorithm, for rancid and wineyvinegary adulterations, respectively) allowed to semi-quantitatively distinguish olive oils with different adulteration levels (repeated K-fold crossvalidation predictive correct classifications of 84±10% and 94±8% for rancid and winey-vinegary adulterations, respectively). The preliminary results showed the practical potential of the E-tongue as a taste device for the successful detection of EVOOs adulterated with LOO containing organoleptic defects. ; This work was financially supported by POCI- 01–0145-FEDER-006984–Associate Laboratory LSRE-LCM, Project UID/QUI/00616/2013 –CQVR, Project UID/BIO/04469/2013 – CEB and Project UID/AGR/00690/2013–CIMO all funded by FEDER, through COMPETE2020, and by national funds through. Nuno Rodrigues thanks FCT, POPH-QREN and FSE for the Ph.D. Grant SFRH/BD/104038/2014. ; info:eu-repo/semantics/publishedVersion

Olive oils may be commercially classified, in a decrease order of quality and economic value, as extra-virgin (EVOO), virgin (VOO) or lampante (LOO) olive oils, being quite prone to frauds. Thus legal protection regulations have been approved by the European Union Commission [1,2], being required the fulfilment of several physicochemical and sensory thresholds [3,4]. Unfortunately, the mixture of expensive olive oils with low quality oils aiming fraudulent economic revenue is still a common practice difficult to detect. In this work, a potentiometric electronic tongue (E-tongue) was used to detect adulteration of an EVOO with different added levels (2.5%, 5%, 10%, 20% and 40%; v/v) of an LOO with an intense sensory defect (rancid or wineyvinegary). Previously, similar electrochemical devices, also comprising lipid polymeric sensor membranes, showed to be able to give qualitative and/or quantitative responses towards basic taste sensations (acid, bitter, salty, sweet, and umami), positive sensory attributes (bitter, fruity, green and pungency) or defects (e.g., butyric, musty, putrid, winey-vinegary and zapateria) [5-8]. The E-tongue coupled with linear discriminant technique (based on the signal profiles of 19 or 20 E-tongue sensors, chosen using a simulated annealing meta-heuristic variable selection algorithm, for rancid and wineyvinegary adulterations, respectively) allowed to semi-quantitatively distinguish olive oils with different adulteration levels (repeated K-fold crossvalidation predictive correct classifications of 84±10% and 94±8% for rancid and winey-vinegary adulterations, respectively). The preliminary results showed the practical potential of the E-tongue as a taste device for the successful detection of EVOOs adulterated with LOO containing organoleptic defects. ; This work was financially supported by POCI- 01–0145-FEDER-006984–Associate Laboratory LSRE-LCM, Project UID/QUI/00616/2013 –CQVR, Project UID/BIO/04469/2013 – CEB and Project UID/AGR/00690/2013 –CIMO all funded by FEDER, through COMPETE2020, and by national funds through. Nuno Rodrigues thanks FCT, POPH-QREN and FSE for the Ph.D. Grant SFRH/BD/104038/2014. ; info:eu-repo/semantics/publishedVersion

"Bee pollen" is pollen collected from flowers by honey bees. It is used by the bees to nourish themselves, mainly by providing royal jelly and brood food, but it is also used for human nutrition. For the latter purpose, it is collected at the hive entrance as pellets that the bees bring to the hive. Bee pollen has diverse bioactivities, and thus has been used as a health food, and even as medication in some countries. In this paper, we provide standard methods for carrying out research on bee pollen. First, we introduce a method for the production and storage of bee pollen which assures quality of the product. Routine methods are then provided for the identification of the pollen's floral sources, and determination of the more important quality criteria such as water content and content of proteins, carbohydrates, fatty acids, vitamins, alkaloids, phenolic and polyphenolic compounds. Finally, methods are described for the determination of some important bioactivities of bee pollen such as its antioxidant, anti-inflammatory, antimicrobial and antimutagenic properties. Métodos estándar Para la investigación del polen El "polen de abeja" es el polen recogido de las flores por las abejas melíferas. El polen de abeja es utilizado para nutrir a las propias abejas, principalmente para proporcionar jalea real y alimento para las crías, pero también se utiliza para la nutrición humana. Para este último fin, se recoge en la entrada de la colmena en forma de gránulos que las abejas llevan a la colmena. El polen de abeja tiene diversas bioactividades, por lo que se hautilizado como alimento para la salud, e incluso como medicamento en algunos países. En este artículo, proporcionamos métodos estándar para llevar a cabo investigaciones sobre el polen de abeja. En primer lugar, presentamos un método de producción y almacenamiento de polen de abeja que garantiza la calidad del producto. A continuación, se ofrecen métodos de rutina para la identificación de las fuentes florales del polen y la determinación de los criterios de calidad más importantes, como el contenido de agua y de proteínas, carbohidratos, ácidos grasos, vitaminas, alcaloides y compuestos fenólicos y polifenólicos. Por último, se describen métodos para la determinación de algunas bioactividades importantes del polen de abeja, como sus propiedades antioxidantes, antiinflamatorias, antimicrobianas y antimutagénicas. ; The COLOSS (Prevention of honey bee COlony LOSSes) Association aims to explain and prevent massive honey bee colony losses. It was funded through the COST Action FA0803. COST (European Cooperation in Science and Technology) is a unique means for European researchers to jointly develop their own ideas and new initiatives across all scientific disciplines through trans-European networking of nationally funded research activities. Based on a pan-European intergovernmental framework for cooperation in science and technology, COST has contributed since its creation more than 40 years ago to closing the gap between science, policy makers and society throughout Europe and beyond. COST is supported by the EU Seventh Framework Program for research, technological development and demonstration activities (Official Journal L 412, 30 December 2006). The European Science Foundation as implementing agent of COST provides the COST Office through an EC Grant Agreement. The Council of the European Union provides the COST Secretariat. The COLOSS network is now supported by the Ricola Foundation – Nature & Culture. Figures 26–28 are reproduced from Sawyer (1981) with the permission of the publishers University College Cardiff Press and Northern Bee Books. Lidia Barreto and J Nordi wish to thank the Apiculture Research Center of Taubate University (UNITAU-SP/Brazil) and Agriculture Secretary of Bahia State (SEAGRI-BA/ BRAZIL). Maria Campos wishes to thank (UI0204): UIDB/ 00313/2020, Center of Chemistry from Faculty of Sciences and Technology of University of Coimbra, Portugal. Of elia Anjos wishes to thank to Forest Research Centre, a research unit funded by Fundac¸~ao para a Ci^encia e a Tecnologia I.P. (FCT), Portugal (UIDB/00239/2020), and to Centro de Biotecnologia de Plantas da Beira Interior for the OPUS software availability. Norma Almaraz Abarca thanks to the Instituto Politecnico Nacional for financial and logistic support. Manuel Chica and Pascual Campoy wish to thank the APIFRESH project. APIFRESH has been co-funded by the European Commission under the R4SMEs 7th Framework Program. Olena Lokutova thanks the Austrian Institute of beekeeping, Dr H Pehhacker and the same members of the Institute H Hagel and E H€uttinger for conducting photomicroscopic studies and pollen analysis Ukrainian samples of pollen loads, which were the basis of the atlas of pollen "honey plants" of Ukraine. Olena is grateful also to Polish colleagues Z Warakomska (Department of Botany University of Lublin) and D Teper (Polish Institute of beekeeping) for their professionalism and consultations to determine the botanical origin of some Ukrainian honey. Also thanks to their scientific advisers' academician G Bogdanov (National Academy of Agrarian Sciences of Ukraine), Prof. V Polishuk (Department of beekeeping National University of Life and Environmental Sciences of Ukraine) and O Martynyuk (M.G. Kholodny Institute of Botany, Kiev, Ukraine) for his helpful co-operation in the field of beekeeping and palinology. Janka Nozkova wishes to thank the Operational Program Research and Development of the European Regional Development Fund in the frame of the project "Support of technologies innovation for special bio-food products for human healthy nutrition" (ITMS 26220220115) and also by the Excellence Center for Agrobiodiversity Conservation and Benefit – project implemented under the Operational Program Research and Development financed by European Fund for Regional Development ITMS 26220120015 (Slovak Republic) and all colleagues from Institute of Biodiversity and Biosafety, Slovak University of Agriculture in Nitra for their help with image analysis. Ananias Pascoal, Georgina Tolentino and Let ıcia Estevinho would like to thank Fundac¸~ao para a Ci^encia e Tecnologia (FCT), Programa Operacional Pontencial Humano (POPH) and European Union (EU) for his Postdoctoral grant SFRH/BPD/91380/2012. Wiebke Sickel, Markus Ankenbrand, Gudrun Grimmer, Frank F€orster, Ingolf Steffan-Dewenter and Alexander Keller thank the financial support by the DFG Collaborative Research Center 1047, Insect Timing. MJA was further supported by a grant of the German Excellence Initiative to the Graduate School of Life Sciences of the University of W€urzburg. They are grateful to the members of the Departments of Animal Ecology and Tropical Biology; Bioinformatics; and Human Genetics, University of W€urzburg, for constructive input on the design of the workflow. Additionally thank to the Department of Human Genetics, especially S. Rost, for granting access to the Illumina MiSeq device. Zivoslav Te si c, Mirjana Mosi c, Aleksandar Kosti c, Mirjana Pe si c, Du sanka Milojkovi c-Opsenica thank the Ministry of Education, Science and Technological Development of Serbia, Grants 172017 and TR 31069. Gina Tolentino would like to thank the Mountain Research Center (CIMO), Agricultural College of Bragança, Polytechnic Institute of Braganc¸a for his research grant in the project titled " Development of new bee products in biological production way." ; info:eu-repo/semantics/publishedVersion