Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Handheld Near-Infrared Spectroscopy for Distinction of Extra Virgin Olive Oil from Other Olive Oil Grades Substantiated by Compositional Data
    Yan, Jing ; Stuijvenberg, Louka van; Ruth, Saskia M. van - \ 2019
    European Journal of Lipid Science and Technology 121 (2019)12. - ISSN 1438-7697
    food fraud - in-situ - one-class classification - pigments - portable

    Miniaturization of analytical technology has paved the way for in-situ screening of foods. In the current study, the spectral features of olive oils are examined by handheld near-infrared spectroscopy to explore the technology's capabilities to distinguish extra virgin olive oil (EVOO) from lower grade oils. Eighty EVOO, forty refined olive oil (ROO), and ten pomace olive oil (POO) samples are analysed for their spectral and compositional features. The latter included analysis of the fatty acids (FAs), the chlorophylls and carotenoids, chromatic coordinates and moisture contents. The 1350–1570 nm wavelength range appeared most suitable for distinction of the oils. One-class classification models with three different classifiers are subsequently estimated using this range, and their quantitative performance is assessed from probabilistic data. Soft independent modeling of class analogies models appears to predict the identity of the oils with a high success rate. Compared to the other oils, POO comprises a significantly higher and lower proportion of polyunsaturated and monounsaturated FAs, respectively. Higher contents of chlorophylls, carotenoids, and moisture are noted for EVOO. The relevant spectral information for distinction of the oils correlates strongly with the degree of unsaturation of the oils as well as their levels of chlorophylls, carotenoids, and moisture. Practical Applications: The findings of this study demonstrate that the handheld NIRS technique is promising for future rapid screening of olive oil grades. The statistical methods used and the robust validation procedure will help potential users to select the optimal strategy for multivariate data analysis. In addition, the exploration of correlations with compositional characteristics provides insight into the handheld NIRS working mechanism in regard to EVOO authentication.

    Stof tot nadenken: vier manieren om de mode-industrie duurzamer te maken
    Louwerens, Tessa ; Poldner, Kim ; Fischer, A.R.H. ; Broek, L.A.M. van den; Dam, J.E.G. van; Houthoff, Iris - \ 2018
    biobased materials - clothing - fibres - algae - biomass - hemp - dyes - pigments - bioplastics - biopolymers - ink - natural products
    Selective and mild fractionation of microalgal proteins and pigments using aqueous two-phase systems
    Suarez Ruiz, Catalina A. ; Emmery, Daniel P. ; Wijffels, Rene H. ; Eppink, Michel H.M. ; Berg, Corjan van den - \ 2018
    Journal of Chemical Technology and Biotechnology 93 (2018)9. - ISSN 0268-2575 - p. 2774 - 2783.
    aqueous two-phase systems - cholinium-based ionic liquids - microalgae biorefinery - pigments - proteins

    BACKGROUND: Microalgal biomass is generally used to produce a single product instead of valorizing all of the cellular components. The biomass production and downstream processes are too expensive if only one product is valorized. A new approach was proposed for the simultaneous and selective partitioning of pigments and proteins from disrupted Neochloris oleoabundans cultivated under saline and freshwater conditions. RESULTS: An aqueous two-phase system composed of polyethylene glycol and cholinium dihydrogen phosphate selectively separated microalgal pigments from microalgal proteins. 97.3 ± 1.0% of lutein and 51.6 ± 2.3% of chlorophyll were recovered in the polymer-rich phase. Simultaneously, up to 92.2 ± 2.0% of proteins were recovered in a third phase (interface) in between the aqueous phases (interface). The recovered proteins, including Rubisco with a molecular weight of ∼560 kDa, seem to be intact and pigments did not suffer degradation, demonstrating the mildness of this system for fractionating microalgal biomolecules. CONCLUSION: The ability of aqueous two-phase systems (ATPSs) to simultaneously and efficiently fractionate different biomolecules in a mild manner from disrupted microalgae is demonstrated. This is an important step towards the development of a multiproduct microalgae biorefinery.

    Christiaan Bolck (Biobased Performance Materials): ‘We doen onderzoek dat impact heeft’
    Bolck, C.H. - \ 2018
    biobased economy - biobased materials - biomass - polymers - bioplastics - dyes - pigments - paints - plant extracts
    Optimale assimilatie eerste vereiste voor goede bloemkleuren : kleur afhankelijk van pigmenten en celstructuur
    Heuvelink, E. ; Kierkels, T. - \ 2016
    Onder Glas 13 (2016)11. - p. 14 - 15.
    bloemen - bloementeelt - glastuinbouw - plantkunde - kleur - pigmenten - flowers - floriculture - greenhouse horticulture - botany - colour - pigments
    Oorspronkelijk zijn bloemkleuren vooral van belang om bestuivers te lokken, maar in de bloemisterij is dat juist niet gewenst. Daar staat de aantrekkelijkheid voor de koper voorop. Er is voortdurend behoefte aan nieuwe spannende kleuren. Bloemkleur is daarmee een economische factor van belang. Veredelaar maar ook teler kunnen het verschil maken.
    Plants4Cosmetics : perspectives for plant ingredients in cosmetics
    Boeriu, C.G. - \ 2015
    Wageningen : Wageningen UR - Food & Biobased Research (Report / Wageningen UR Food & Biobased Research 1603) - 38
    cosmetics - plants - flavonoids - phenols - pigments - plant pigments - polysaccharides - geranium - hyacinthus - chrysanthemum - orchidaceae - skin - hair - oil plants - medicinal plants - natural products - biobased chemicals - biobased economy - cosmetica - planten - flavonoïden - fenolen - pigmenten - plantenpigmenten - polysacchariden - geranium - hyacinthus - chrysanthemum - orchidaceae - huid - haar - olieleverende planten - medicinale planten - natuurlijke producten - chemicaliën uit biologische grondstoffen - biobased economy
    In opdracht van Bio Base Westland en de TKI Tuinbouw Koepel PPS Plantenstoffen, heeft Wageningen UR – Food & Biobased Research een exploratieve desktop studie uitgevoerd gericht op de identificatie van veelbelovende routes voor de valorisatie van plantinhoudstoffen - waaronder ook reststromen uit de tuinbouw - voor de cosmetische industrie. Een uitgebreide analyse van de beschikbare informatie werd uitgevoerd om de mogelijkheden voor de Nederlandse tuinbouwsector te bepalen. Er is gekeken naar marktkansen in de cosmetische industrie met inbegrip van natuurlijke en biologische ingrediënten.
    Preliminary UHPLC–PDA–ESI-MS screening of light-accelerated autoxidation products of the tetrapyrrole biliverdin
    Weesepoel, Y.J.A. ; Gruppen, H. ; Vincken, J.P. - \ 2015
    Food Chemistry 173 (2015). - ISSN 0308-8146 - p. 624 - 628.
    spirulina-platensis - mass-spectrometry - c-phycocyanin - stability - preservatives - antioxidants - pigments
    The application of phycobiliproteins, e.g. blue C-phycocyanin, as natural water-soluble food colourants is emerging. The chromophore of these proteins comprises a number of tetrapyrroles (or phycocyanobilins), which have an extensive conjugated system, vulnerable to autoxidation. To assess the autoxidation products, a simplified model system was used in which the free tetrapyrrole biliverdin, instead of phycobiliprotein, was subjected to light-accelerated autoxidation. Degradation products of biliverdin were subsequently annotated by reversed-phase ultra-high performance liquid chromatography with a photo diode array and positive mode in-line electrospray ionization mass spectrometry. To facilitate the analysis of degradation products, autoxidation of the three methine bridges in biliverdin was mimicked in silico. It was found that both the peripheral and central methine bridges of biliverdin were susceptible to light-accelerated autoxidation. Scission products tentatively annotated with MS2 and MS3 were propionic acid-containing pyrroles. From this, it can be speculated that tetrapyrroles attached to phycobiliproteins are susceptible to autoxidative degradation.
    Phototrophic pigment production with microalgae
    Mulders, K.J.M. - \ 2014
    Wageningen University. Promotor(en): Rene Wijffels, co-promotor(en): Dirk Martens; Packo Lamers. - Wageningen : Wageningen University - ISBN 9789462571457 - 179
    algen - fototropie - pigmenten - natuurlijke producten - metabolisme - carotenoïden - licht - gerichte mutagenese - algae - phototropism - pigments - natural products - metabolism - carotenoids - light - targeted mutagenesis

    Microalgal pigments are regarded as natural alternatives for food colorants. To facilitate optimization of microalgae-based pigment production, this thesis aimed to obtain key insights in the pigment metabolism of phototrophic microalgae, with the main focus on secondary carotenoids.

    Different microalgal groups each possess their own set of primary pigments. Besides, a selected group of green algae (Chlorophytes) accumulate secondary pigments (secondary carotenoids) when exposed to oversaturating light conditions.

    In this thesis it was found for the first time that nutrient-depleted Isochrysis. aff. galbana T-ISO (Haptophytes) accumulates 3-hydroxyechinenone, a precursor of astaxanthin. Besides, it was found that nitrogen-depleted Chromochloris (Chlorella) zofingiensis (Chlorophyes) accumulates astaxanthin, presumably synthesised via echinenone, and ketolutein.

    Inhibition of production of β-carotene derivatives (e.g. echinenone and astaxanthin) did not lead to increased production of primary carotenoids (e.g. lutein) or ketolutein in this species, suggesting that the regulatory mechanisms controlling the flux towards ketolutein and primary carotenoids are not affected by the decreased levels of β-carotene derivatives.

    Besides, optimal yields of secondary carotenoids and triacylglycerol (TAG) on light were reached with C. zofingiensis for a range of biomass concentrations at the moment of nitrogen depletion.

    This indicated that the biomass-specific photon absorption rate did not affect the amounts of energy used for secondary carotenoid and TAG production, for the range of biomass concentrations tested.

    It was also found that nitrogen-depleted C. zofingiensis resupplied with nitrogen hardly degraded astaxanthin, whereas the other major secondary metabolites were degraded rapidly.

    This indicated that the overall carotenoid yield on light as well as its content may possibly be improved by applying a repeated batch instead of a series of single batch cultivations, which are traditionally applied.

    Finally, it was discussed that the highest increases in carotenoid yield on light can be reached by optimizing strain performance (using targeted genetic engineering and/or random mutagenesis), rather than by optimizing the cultivation conditions/operation mode or reactor design.

    Red Light Represses the Photophysiology of the Scleractinian Coral Stylophora pistillata
    Wijgerde, T.H.M. ; Melis, A.A.M. ; Ferreira Da Silva, C.I. ; Leal, M.C. ; Vogels, L. ; Mutter, C. ; Osinga, R. - \ 2014
    PLoS ONE 9 (2014)3. - ISSN 1932-6203
    green fluorescent protein - reef-building corals - chlorophyll biosynthesis - zinc toxicity - cell-cycle - zooxanthellae - photosynthesis - aquaculture - performance - pigments
    Light spectrum plays a key role in the biology of symbiotic corals, with blue light resulting in higher coral growth, zooxanthellae density, chlorophyll a content and photosynthesis rates as compared to red light. However, it is still unclear whether these physiological processes are blue-enhanced or red-repressed. This study investigated the individual and combined effects of blue and red light on the health, zooxanthellae density, photophysiology and colouration of the scleractinian coral Stylophora pistillata over 6 weeks. Coral fragments were exposed to blue, red, and combined 50/50% blue red light, at two irradiance levels (128 and 256 µmol m-2 s-1). Light spectrum affected the health/survival, zooxanthellae density, and NDVI (a proxy for chlorophyll a content) of S. pistillata. Blue light resulted in highest survival rates, whereas red light resulted in low survival at 256 µmol m-2 s-1. Blue light also resulted in higher zooxanthellae densities compared to red light at 256 µmol m-2 s-1, and a higher NDVI compared to red and combined blue red light. Overall, our results suggest that red light negatively affects the health, survival, symbiont density and NDVI of S. pistillata, with a dominance of red over blue light for NDVI.
    Stability of fatty acids during wilting of perennial ryegrass (Lolium perenne L.): effect of bruising and environmental conditions
    Khan, N.A. ; Cone, J.W. ; Fievez, V. ; Hendriks, W.H. - \ 2011
    Journal of the Science of Food and Agriculture 91 (2011)9. - ISSN 0022-5142 - p. 1659 - 1665.
    light-dependent degradation - cutting date - lipid-metabolism - senescence - cultivar - forages - silage - additives - pigments - interval
    BACKGROUND: Oxidation of fatty acids (FA) during field wilting of herbage could cause extensive losses of polyunsaturated FA. Recent studies showed a variable effect of wilting on the losses of FA. This suggests that environment and management conditions influence the loss of FA during wilting. The present study investigated the stability of FA in untreated and mechanically bruised perennial ryegrass, wilted under field conditions for 0, 12, 24, 36 and 48 h, or wilted under controlled climate conditions at three temperatures (15, 25 or 35 °C) and two light (dark or light) regimes to dry matter (DM) contents of 425, 525 or 625 g kg-1. RESULTS: During 48 h of field wilting, the total FA content declined (15.2 to 11.9 g kg-1 DM) consistently, despite an increase in herbage DM content (197 to 676 g kg-1). Under controlled climate conditions, the herbage total FA content declined (15.1 to 11.7 g kg-1 DM) mainly during the prolonged (56 to 62 h) initial drying to a DM content of 425 g kg-1 and did not decline with further drying to DM contents of 525 and 625 g kg-1. The decline in total FA was associated with a parallel decline in C18:3 content under field (9.15 to 6.36 g kg-1 DM) and controlled (9.12 to 6.15 g kg-1 DM) conditions. Concomitantly, the proportion of C18:3 in total FA decreased, whilst the proportion of C16:0 and C18:0 increased. Lower losses of FA (P <0.05) were observed at 15 °C compared to 25 and 35 °C. Light did not affect the losses of FA during wilting. CONCLUSIONS: The duration of the wilting period mainly affected the changes in FA content and composition. Stability of FA in herbage could be increased by minimising the duration of wilting.
    Carotenoid fluorescence in Dunaliella salina
    Kleinegris, D.M.M. ; Es, M.A. van; Janssen, M.G.J. ; Brandenburg, W.A. ; Wijffels, R.H. - \ 2010
    Journal of Applied Phycology 22 (2010)5. - ISSN 0921-8971 - p. 645 - 649.
    beta-carotene - spectroscopy - pigments
    Dunaliella salina is a halotolerant green alga that is well known for its carotenoid producing capacity. The produced carotenoids are mainly stored in lipid globules. For various research purposes, such as production and extraction kinetics, we would like to determine and/or localise the carotenoid globules in vivo. In this study, we show that the carotenoid-rich globules emit clear green fluorescence, which can be used in, for example, fluorescence microscopy (e.g. CLSM) to obtain pictures of the cells and their carotenoid content.
    Antioxidants, phenolic compounds, and nutritional quality of different strawberry genotypes
    Tulipani, S. ; Mezzetti, B. ; Capocasa, F. ; Bompadre, S. ; Beekwilder, M.J. ; Vos, C.H. de; Capanoglu, E. ; Bovy, A.G. ; Battino, M. - \ 2008
    Journal of Agricultural and Food Chemistry 56 (2008)3. - ISSN 0021-8561 - p. 696 - 704.
    fragaria x ananassa - vitamin-c - berry phenolics - capacity - fruit - vegetables - identification - pigments - assay - anthocyanins
    Strawberry contains high levels of micronutrients and phytochemical compounds. These exhibit functional roles in plant growth and metabolism and are also essential for the nutritional and organoleptic qualities of the fruit. The aim of the present work was to better characterize the phytochemical and antioxidant profiles of the fruit of nine different genotypes of strawberry, by measuring the total flavonoid, anthocyanin, vitamin C, and folate contents. Cultivar effects on the total antioxidant capacities of strawberries were also tested. In addition, the individual contribution of the main antioxidant compounds was assessed by HPLC separation coupled to an online postcolumn antioxidant detection system. This study showed the important role played by the genetic background on the chemical and antioxidant profiles of strawberry fruits. Significant differences were found between genotypes for the total antioxidant capacity and for all tested classes of compounds. The HPLC analyses confirmed qualitative and quantitative variability in the antioxidant profiles. These studies show that differences exist among cultivars, applicable in dietary studies in human subjects.
    Maillard-reactie door model beheersbaar
    Roost, M. van - \ 2006
    Elsevier Voedingsmiddelen Industrie 2006 (2006)1. - ISSN 1570-6907 - p. 22 - 23.
    voedselchemie - voedseltechnologie - maillard-reactie - bruinkleuring - simulatiemodellen - pigmenten - ph - zuurgraad - suikers - eiwitten - kwaliteit - smaak - productieprocessen - food chemistry - food technology - maillard reaction - browning - simulation models - pigments - ph - acidity - sugars - proteins - quality - taste - production processes
    Gewenste en ongewenste bruinkleuring van levensmiddelen door een Maillard-reactie is vaak lastig te beheersen. Wageningse onderzoekers ontwikkelden een simulatiemodel, waarmee producentenmeer inzicht krijgen in de Maillard-reactie, en zo ook de kleur van het eindproduct beter kunnen beheersen tijdens het productieproces en de opslag. Met schematische weergave van de Maillard-reactie
    Cactus pear and cochineal in Cochabamba: the development of a cross-epistemological management toolkit for interactive design of farm innovation
    Tekelenburg, A. - \ 2002
    Wageningen University. Promotor(en): N.G. Röling; E.A. Goewie. - S.l. : S.n. - ISBN 9789058084798 - 191
    bedrijfssystemen - innovaties - ontwerp - leren - interacties - cactaceae - opuntia ficus-indica - kleur - kleurstoffen (dyes) - verfsoorten - pigmenten - bolivia - coccidae - insecten - plantenplagen - voorlichting - participatie - boeren - integratie - plattelandsontwikkeling - bedrijfsvoering - landbouw - natuurlijke hulpbronnen - nuttig gebruik - bodemdegradatie - wetenschap - farming systems - innovations - design - learning - rural development - management - extension - participation - farmers - agriculture - natural resources - utilization - soil degradation - interactions - integration - cactaceae - opuntia ficus-indica - coccidae - insects - plant pests - colour - dyes - paints - pigments - bolivia - science

    In this book, the local research and development process of the small-farmers (campesino) union of Huancarani (Cochabamba region in Bolivia) is discussed. Research activities were carried out by farmers themselves as well as by facilitators and scientists, but the farmers union kept control on planning, evaluation, decision-making and action. The book refers on the one hand to a technical issue; the development of cactus pear (Opuntia ficus-indica M.) and cochineal (Dactylopius coccus C.) production. The main question became why the experience was so successful. On the other hand it refers to a social issue (when the relation between farmers and scientists is addressed and applied methodology is analysed). The intellectual challenge for me was to show to a large and diversified public that, from a particular project, lessons can be drawn to improve interactive learning for farm innovation. This challenge has everything to do with the cooperation and communication issue between farmers and scientists. The exercise covers a reconstructed logic of applied research, design and development methodology and is therefore abstract. The final result of this exercise was the production of the management toolkit for the design of interactive learning processes. This toolkit became a practical instrument for managing and facilitating farm innovation processes in other contexts. It is the development of this toolkit, the learning process, based on the mantra learning in practice - learning from practice - learning for practice, that I want to share with other scientists and development workers.

    Dubbele emulsies controleren afgifte of scheiding voedingscomponenten
    Horst, B.M. van der; Langelaan, H.C. - \ 1999
    Voedingsmiddelentechnologie 32 (1999)24. - ISSN 0042-7934 - p. 10 - 16.
    ingrediënten - voedselindustrie - voedseltechnologie - emulsies - dispersie - emulgeermiddelen - scheiding - segregatie - zuiveren - filtratie - technologie - verwerking - vloeistoffen (liquids) - pigmenten - modellen - ingredients - food industry - food technology - emulsions - dispersion - emulsifiers - separation - segregation - purification - filtration - technology - processing - liquids - pigments - models
    Een nieuw concept voor het scheiden van voedingscomponenten, alsmede voor toepassing in de cosmetische en farmaceutische industrie. Het onderzoek op dit gebied door ATO-DLO is gericht op het encapsuleren van (vluchtige) componenten, nieuwe emulgeringsmethoden, bereidingsaspecten, lange termijnstabiliteit, reologische eigenschappen, typen emulgatoren en gecontroleerde afgifte. Tevens werd een modelsysteem ontwikkeld voor het verwijderen van ongewenste componenten uit voedingsmiddelen
    Traceren van boter d.m.v. het toevoegen van kleur- en/of smaakstoffen
    Labrijn, J.F. ; Schouten, J.C. ; Veen, N.G. van der; Sledsens, A.M.J. - \ 1985
    Wageningen : RIKILT (Rapport / RIKILT 85.109) - 3
    boter - toevoegingen - pigmenten - kleurstoffen (dyes) - butter - additives - pigments - dyes
    Verschillende kleur- en aromastoffen zoals indigotine, chlorofyl , enocyanine, bietenrood, vanille en een lakton zijn in verschillende hoeveelheden aan boter toegevoegd. De verdeling van de kleur- en aromastoffen was in de meeste gevallen homogeen. De kleuring was bij verschillende concentraties voldoende om als tracer te gebruiken. Een vereiste was echter dat de kleur grotendeels afgebroken werd bij verhitten. Dit was bij een aantal kleurstoffen het geval.
    Afwerking van vloeren en wanden in stallen met epoxy
    Hangelbroek, P.B. - \ 1972
    Wageningen : [s.n.] (Mededeling / Instituut voor landbouwbedrijfsgebouwen no. 53) - 3
    huisvesting, dieren - verfsoorten - afdeklagen - vernissen - afwerkmiddelen - dierenwelzijn - kleur - industrie - pigmenten - fabricage - kleurstoffen (dyes) - animal housing - paints - coatings - varnishes - finishes - animal welfare - colour - industry - pigments - manufacture - dyes
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