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.

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Micro-alg doet oliepalm na
Jaeger, L. de - \ 2015
Resource: weekblad voor Wageningen UR 10 (2015)5. - ISSN 1874-3625 - p. 9 - 9.
algen - plantaardige oliën - voedselbiotechnologie - genetisch gemanipuleerde organismen - spijsoliën - onderzoek - algae - plant oils - food biotechnology - genetically engineered organisms - edible oils - research
Veel plantaardige olie in ons dieet komt van palmolieplantages uit Zuidoost-Azië waarvoor regenwoud is gekapt. Promovendus Lenny de Jaeger zocht naar een alg die deze olie op duurzame wijze kan maken. Hij ontwikkelde een veelbelovende kandidaat.
Polymer organogelation with chitin and chitin nanocrystals
Nikiforidis, C.V. ; Scholten, E. - \ 2015
RSC Advances : An international journal to further the chemical sciences 5 (2015)47. - ISSN 2046-2069 - p. 37789 - 37799.
mechanical characterization - supramolecular gels - lecithin organogel - molecular-weight - edible oils - chitosan - derivatives - morphology - chemistry - mixtures
In this paper, we show that biodegradable and biocompatible organogels can be formed with chitin as the filler material and triglycerides as the continuous hydrophobic phase. When crude chitin was used, a large degree of aggregation was observed that prevented the formation of stable organogels. Two approaches were used to diminish this degree of aggregation and increase the stability. Either surfactants were used to increase the dispersability of the crude chitin, or the crude chitin was transformed into smaller rod-like nanocrystals by acid hydrolysis. Both approaches led to the formation of stable organogels with storage moduli up to 106 Pa for high chitin concentrations (20 wt%). Three different types of surfactants were used, namely phosphatidylcholine, enzymatically modified phosphatidylcholine and sorbitan monostearate (Span 60). The choice of surfactant has a large influence on the gel strength and the temperature sensitivity of the gels. With chitin nanocrystals, in the presence of surfactants, larger gel strengths were observed for lower concentrations (1-10 wt%), indicating more efficient packing of the particles. Gels were stable even after addition of considerable amounts of water up to 25 wt%. The increase in gel strength in the presence of water (storage modulus) was most likely an effect of the water absorption ability of chitin that increased the effective volume fraction of the fillers.
Business opportunities and food safety of the Myanmar edible oil sector
Wijnands, J.H.M. ; Biersteker, J. ; Hagedoorn, L.F. ; Louisse, J. - \ 2014
Wageningen : LEI Wageningen UR (Report / LEI Wageningen UR 2014-036) - ISBN 9789086157013 - 94
oliezaden - spijsoliën - voedselveiligheid - sesamolie - palmoliën - export - bedrijfseconomie - myanmar - oilseeds - edible oils - food safety - sesame oil - palm oils - exports - business economics
This report analyses the business opportunities of the oilseed and edible oil sector in Myanmar as well as the food safety control system. Myanmar is a significant producer of oilseed specialities. It is world’s largest producer of sesame seeds, ranks on the sixth position for groundnut production and for mustard seeds on the third position. However, the exports are insignificant. The food safety control system of this sector is developed weakly. Myanmar has huge opportunities on the world market: foreign currency earnings are in the magnitude of country’s total trade deficit by exporting sesame oil substituted by importing a same amount of palm oil.
Verification of fresh grass feeding, pasture grazing and organic farming by FTIR spectroscopy analysis of bovine milk
Capuano, E. ; Rademaker, J. ; Bijgaart, H. van den; Ruth, S.M. van - \ 2014
Food Research International 60 (2014). - ISSN 0963-9969 - p. 59 - 65.
near-infrared spectroscopy - fatty-acid-composition - total mixed ration - geographic origin - edible oils - dairy-cows - fluorescence - cheese - food - differentiation
In the present study, a total of 116 tank milk samples were collected from 30 farms located in The Netherlands and analysed by Fourier-transform infrared (FTIR) spectroscopy. Samples were collected in April, May and June 2011 and in February 2012. The samples differed in the time spent by the cows on pasture, presence/absence of fresh grass in the daily ration and the farming system (organic/biodynamic or conventional). Classification models based on partial least square discriminant analysis (PLS-DA) of FTIR spectra were developed for the prediction of fresh grass feeding, pasture grazing and organic farming. The PLS-DA model discriminated between milk from cows that had fresh grass in the daily ration and milk from cows that had not fresh grass with sensitivity and specificity values of 88% and 83% in external validation and all the samples from cows that had no fresh grass collected in spring were correctly classified. The PLS-DA model developed for the authentication of pasture grazing showed comparable accuracy when the whole sample set is considered but was less accurate on the spring samples (75% of samples from cows indoors in spring correctly classified). Discrimination of organic and conventional milk was also accomplished with acceptable accuracy with % correct classification of 80% and 94% respectively in external validation. The results suggest that milk FTIR spectra contain valuable information on cows' diet that can be used for authentication purposes.
Self-assemblies of lecithin and a-tocopherol as gelators of lipid material
Nikiforidis, C.V. ; Scholten, E. - \ 2014
RSC Advances : An international journal to further the chemical sciences 4 (2014)5. - ISSN 2046-2069 - p. 2466 - 2473.
edible oils - rheological properties - reverse micelles - drug-delivery - fatty-acids - organogels - gels - mixtures - agents
Amongst the different mechanisms that have been proposed and used to structure organogels, self-assembly of the gelators into supramolecular structures linked through non-covalent bonds is the most interesting. The gelator activity of LMGOs is often found most effective when micellar or lamellar phases are obtained, which is dependent on the gelator geometry and the specific packing parameter. Gelation can therefore be induced by altering the packing parameter of different gelators, but due to the law restrictions there are only a few edible gelators that can be used to structure edible lipids. Here, we show that a combination of a-tocopherol and phosphatidylcholine (PC) can be used to alter the packing geometry to provide supramolecular structures needed for the organogelation. We have observed that when the gelators were combined at 1:1 ratio in sunflower oil, edible organogels were obtained. The firmness of the solid-like material was enhanced when 1.0 wt% of water was added. The proposed mechanism for this assembly is that most likely cylindrical micellar structures are formed, due to combined assembly of the a-tocopherol and phosphatidylcholine, stabilized through physical interactions. Since these interactions, and the accompanied packing geometry, depends on temperature and application of external stresses, the formation of the organogels showed reversibility when the organogels were subjected to shear or when the temperature was increased to values above 35 oC. Polarized microscopy along with small angle X-ray scattering were used to provide a hypothesis for the mechanism behind the gelation.
The influence of the type of oil phase on the self-assembly process of ¿-oryzanol + ß-sitosterol tubules in organogel systems
Sawalha, H.I.M. ; Margry, G. ; Adel, R. den; Venema, P. ; Bot, A. ; Flöter, E. ; Linden, E. van der - \ 2013
European Journal of Lipid Science and Technology 115 (2013)3. - ISSN 1438-7697 - p. 295 - 300.
edible oils - emulsions - mixtures
Mixtures of ¿-oryzanol and ß-sitosterol were used to structure different oils (decane, limonene, sunflower oil, castor oil and eugenol). The ¿-oryzanol and ß-sitosterol mixtures self-assemble into double-walled hollow tubules (~10 nm in diameter) in the oil phase, which aggregate to form a network resulting in firm organogels. The self-assembly of the sterol molecules into tubules was studied using light scattering and rheology. By using different oils, the influence of the polarity of the oil on the self-assembly was studied. The effects of temperature and structurant concentration on the tubular formation process were determined and the thermodynamic theory of self-assembly was applied to calculate the change in Gibbs free energy ( DG0), enthalpy (DH0) and entropy ( DS0) resulting from the aggregation of the structurants was determined. The self-assembly was found to be enthalpy-driven as characterized by a negative DH0 and DS0. A decreasing polarity of the oil promotes the self-assembly leading to formation of tubules at higher temperatures and lower structurants concentrations.
Refined hazard characterization of 3-MCPD using benchmark dose modeling
Rietjens, I.M.C.M. ; Scholz, G. ; Berg, I. van den; Schilter, B. ; Slob, W. - \ 2012
European Journal of Lipid Science and Technology 114 (2012)10. - ISSN 1438-7697 - p. 1140 - 1147.
3-monochloropropane-1,2-diol 3-mcpd - edible oils - in-vivo - esters - mutagenicity - 3-chloropropane-1,2-diol - exposure - acid - food
3-Monochloropropane-1,2-diol (3-MCPD)-esters represent a newly identified class of food-borne process contaminants of possible health concern. Due to hydrolysis 3-MCPD esters constitute a potentially significant source of free 3-MCPD exposure and their preliminary risk assessment was based on toxicological data on free 3-MCPD. 3-MCPD is a non-genotoxic carcinogen and a (provisional maximum) tolerable daily intake ((PM)TDI) of 2 mu g/kg bodyweight per day was established by the Scientific Committee on Food and the Joint FAO/WHO Expert Committee on Food Additives. Both committees derived the TDI from a lowest observed adverse effect level, not a no observed adverse effect level, for renal tubular hyperplasia, using an uncertainty factor of 500. When using the Benchmark Dose (BMD) approach and a BMDL10 value as point of departure, part of this uncertainty factor of 500 would no longer be needed. The present study presents a BMD analysis of the currently available chronic data on 3-MCPD mediated induction of tubular hyperplasia in rats as the most sensitive endpoint. The results indicate a (model-averaged) BMDL10 value of 0.72 mg/kg bw/day. The TDI that would be derived based on this BMDL10 value will depend on the uncertainty factor chosen. Using the default uncertainty factor of 100 for inter- and intraspecies extrapolation would result in a TDI of 7 mu g/kg bw/day.
Elucidation of density profile of self-assembled sitosterol + oryzanol tubules with small-angle neutron scattering
Bot, A. ; Gilbert, E.P. ; Bouwman, W.G. ; Sawalha, H.I.M. ; Adel, R. den; Garamus, V.M. ; Venema, P. ; Linden, E. van der; Flöter, E. - \ 2012
Faraday Discussions 158 (2012). - ISSN 1359-6640 - p. 223 - 238.
gamma-oryzanol - beta-sitosterol - edible oils - fatty alcohols - mixtures - organogels - emulsions - wax - fa
Small-angle neutron scattering (SANS) experiments have been performed on self-assembled tubules of sitosterol and oryzanol in triglyceride oils to investigate details of their structure. Alternative organic phases (deuterated and non-deuterated decane, limonene, castor oil and eugenol) were used to both vary the contrast with respect to the tubules and investigate the influence of solvent chemistry. The tubules were found to be composed of an inner and an outer shell containing the androsterol group of sitosterol or oryzanol and the ferulic acid moieties in the oryzanol molecule, respectively. While the inner shell has previously been detected in SAXS experiments, the outer shell was not discernible due to similar scattering length density with respect to the surrounding solvent for X-rays. By performing contrast variation SANS experiments, both for the solvent and structurant, a far more detailed description of the self-assembled system is obtainable. A model is introduced to fit the SANS data; we find that the dimensions of the inner shell agree quantitatively with the analysis performed in earlier SAXS data (radius of 39.4 +/- 5.6 A for core and inner shell together, wall thickness of 15.1 +/- 5.5 A). However, the newly revealed outer shell was found to be thinner than the inner shell (wall thickness 8.0 +/- 6.5 A). The changes in the scattering patterns may be explained in terms of the contrast between the structurant and the organic phase and does not require any subtle indirect effects caused by the presence of water, other than water promoting the formation of sitosterol monohydrate in emulsions with aqueous phases with high water activity
Organogel-emulsions with mixtures of ß-sitosterol + [gamma]-oryzanol: Influence of water activity and type of oil phase on gelling capability
Sawalha, H.I.M. ; Adel, R. den; Venema, P. ; Bot, A. ; Flöter, E. ; Linden, E. van der - \ 2012
Journal of Agricultural and Food Chemistry 60 (2012)3. - ISSN 0021-8561 - p. 3462 - 3470.
edible oils - phytosterols - wax
In this study, w/o-emulsions were prepared from water containing different salt concentrations dispersed in an oil phase containing mixture of ß-sitosterol and ¿-oryzanol. In pure oil the ß-sitosterol and ¿-oryzanol molecules self-assemble into tubular microstructures to produce a firm organogel. However, in the emulsion the water molecules bind to the ß-sitosterol molecules forming monohydrate crystals, which hinder the formation of the tubules, resulting in a weaker emulsion-gel. Addition of salt to the water phase decreases the water activity, thereby suppressing the formation of sitosterol monohydrate crystals even after prolonged storage times (~ 1 year). The formation of tubular microstructure in the emulsion was further investigated by using several oils with differing polarity. With low polarity oils such as decane and limonene, the formation of hydrated sitosterol crystals was suppressed and the tubular microstructure was promoted which significantly increased the firmness of the emulsion-gel. The main conclusion of this study is that the formation oryzanol and sitosterol tubular microstructure in the emulsion can be promoted by reducing the water activity and/or by using oils with low polarity.
Small-scale edible oil milling operations: Alternative business models for Ethiopia
Sertse, Y. ; Ruijter de Wildt, M.J.M. de; Dijkxhoorn, Y. ; Danse, M.G. - \ 2011
The Hague : LEI, part of Wageningen UR (LEI memorandum : Research area Markets & Chains ) - 50
oliezaden - spijsoliën - maling - zelfvoorziening - ethiopië - overheidsbeleid - economische aspecten - oilseeds - edible oils - milling - self sufficiency - ethiopia - government policy - economic aspects
The Ethiopian government is aiming to achieve self-sufficiency in edible oil by 2015. The aim of this research was to develop sustainable business models for millers, increase their competitiveness, and enhance food safety and security in Ethiopia within the changing policy context.
Voedingsmiddelenanalyses van de Afdeling Humane Voeiding. Deel 14 Vetzuursamenstelling van frituurvetten en bakkerijmargarines in Nederland in 2004
Hulshof, P.J.M. ; Kosmeyer, T. ; Siebelink, E. ; Katan, M.B. - \ 2005
Wageningen : Wageningen Universiteit, Sectie Humane voeding - 18
voedingsmiddelen - chemische samenstelling - vetten - oliën - bakoliën - bakvetten - boter - margarine - voedingswaarde - voedsel - voedselsamenstelling - kwaliteit - eigenschappen - huishoudens - ziekenhuizen - ziekenhuiscatering - verpleeghuizen - dierlijke producten - ingrediënten - Ghana - Filippijnen - spijsoliën - spijsvetten - institutionele huishoudens - foods - chemical composition - fats - oils - cooking oils - cooking fats - butter - nutritive value - food - food composition - quality - properties - households - hospitals - hospital catering - nursing homes - animal products - ingredients - Philippines - edible oils - edible fats - institutional households
Voedingsmiddelenanalyses van de Vakgroep Humane Voeding en Epidemiologie. Deel 12 Retinol en carotenoiden in zuivelproducten
Hulshof, P.J.H. ; Roekel, T. van; Bovenkamp, P. van de; West, C.E. ; Katan, M.B. - \ 2001
Unknown Publisher
voedingsmiddelen - chemische samenstelling - vetten - oliën - bakoliën - bakvetten - boter - margarine - voedingswaarde - voedsel - voedselsamenstelling - kwaliteit - eigenschappen - huishoudens - ziekenhuizen - ziekenhuiscatering - verpleeghuizen - dierlijke producten - ingrediënten - ghana - filippijnen - spijsoliën - spijsvetten - institutionele huishoudens - foods - chemical composition - fats - oils - cooking oils - cooking fats - butter - nutritive value - food - food composition - quality - properties - households - hospitals - hospital catering - nursing homes - animal products - ingredients - philippines - edible oils - edible fats - institutional households
Voedingsmiddelenanalyses van de Vakgroep Humane Voeding. Deel 12 Margarines, spijsvetten, koekjes en snacks-1996
Hulshof, P.J.H. ; Kosmeijer, T. ; Zock, P.L. ; Bovenkamp, P. van de; Katan, M.B. - \ 1998
Unknown Publisher
voedingsmiddelen - voedsel - chemische samenstelling - bakoliën - bakvetten - oliën - boter - margarine - voedingswaarde - voedselsamenstelling - kwaliteit - eigenschappen - huishoudens - ziekenhuizen - vetten - ziekenhuiscatering - verpleeghuizen - ingrediënten - dierlijke producten - ghana - filippijnen - spijsoliën - spijsvetten - institutionele huishoudens - foods - food - chemical composition - cooking oils - cooking fats - oils - butter - nutritive value - food composition - quality - properties - households - hospitals - fats - hospital catering - nursing homes - ingredients - animal products - philippines - edible oils - edible fats - institutional households
Daling transvetzuren, maar niet in alle grootverbruikproducten: vetzuursamenstelling van spijsvetten, koek en snacks.
Hulshof, P.J.M. ; Zock, P.L. ; Kosmeijer-Schuil, J.G. ; Bovenkamp, P. van de; Katan, M.B. - \ 1998
Voeding 59 (1998)5. - ISSN 0042-7926 - p. 24 - 27.
vetzuren - carbonzuren - vetten - oliën - bakoliën - bakvetten - zoetwaren - biscuits - fabricage - cakes - snacks - maaltijden - voedingsmiddelen - chemische samenstelling - voeding - oleïnezuur - onverzadigde vetzuren - acrylzuur - volksgezondheid - gezondheidszorg - spijsoliën - spijsvetten - fatty acids - carboxylic acids - fats - oils - cooking oils - cooking fats - confectionery - manufacture - meals - foods - chemical composition - nutrition - oleic acid - unsaturated fatty acids - acrylic acid - public health - health care - edible oils - edible fats
Deze vetzuren hebben een ongunstige invloed op het lipoproteineprofiel in het bloed. In een tabel is de vetzuursamenstelling van geselecteerde koek en snacks weergegeven. Tegenwoordig bevatten de margarines, bak- en braadvetten aanzienlijk minder verzadigd vet
Voedingsgewoonten van overvloed en onbehagen.
Hartog, A.P. den - \ 1996
Voeding 57 (1996)11. - ISSN 0042-7926 - p. 6 - 9.
consumentengedrag - consumptiepatronen - bakvetten - bakoliën - vetten - voedsel - voedselhygiëne - voedselinkoop - voedingsmiddelen - geschiedenis - voedingstoestand - oliën - prijzen - inkopen - sociale klassen - zoetstoffen - spijsvetten - spijsoliën - consumer behaviour - consumption patterns - cooking fats - cooking oils - fats - food - food hygiene - food purchasing - foods - history - nutritional state - oils - prices - purchasing - social classes - sweeteners - edible fats - edible oils
Vijf artikelen waarin de volgende aspecten zijn belicht: -) vijftig jaar eten in Nederland; -) sociale klasseverschillen in (op)voeding; -) voedingsaankopen in het gezin; -) invloed sociale omgeving; -) effectiviteit van vet- en suikervervangers
Voedingsmiddelenanalyses van de Vakgroep Humane Voeding. Deel 11 Spijsvetten en oliën
Hulshof, P.J.M. ; Bovenkamp, P. van de; Boogerd, L. ; Bos, J. ; Germing-Nouwen, C. ; Kosmeijer-Schuil, T. ; Hollman, P.C.H. ; Katan, M.B. - \ 1991
Unknown Publisher
voedingsmiddelen - chemische samenstelling - vetten - oliën - bakoliën - bakvetten - boter - margarine - voedingswaarde - voedsel - voedselsamenstelling - kwaliteit - eigenschappen - huishoudens - ziekenhuizen - ziekenhuiscatering - verpleeghuizen - ingrediënten - dierlijke producten - ghana - filippijnen - spijsoliën - spijsvetten - institutionele huishoudens - foods - chemical composition - fats - oils - cooking oils - cooking fats - butter - nutritive value - food - food composition - quality - properties - households - hospitals - hospital catering - nursing homes - ingredients - animal products - philippines - edible oils - edible fats - institutional households
Voedingsmiddelenanalyses van de Vakgroep Humane Voeding. Deel 11A Spijsvetten en oliën : achtergrondcijfers
Hulshof, P.J.M. ; Bovenkamp, P. van de; Boogerd, L. ; Bos, J. ; Germing-Nouwen, C. ; Kosmeijer-Schuil, T. ; Katan, M.B. - \ 1990
Unknown Publisher
voedingsmiddelen - chemische samenstelling - vetten - oliën - bakoliën - bakvetten - boter - margarine - voedingswaarde - voedsel - voedselsamenstelling - kwaliteit - eigenschappen - huishoudens - ziekenhuizen - ziekenhuiscatering - verpleeghuizen - ingrediënten - dierlijke producten - ghana - filippijnen - spijsoliën - spijsvetten - institutionele huishoudens - foods - chemical composition - fats - oils - cooking oils - cooking fats - butter - nutritive value - food - food composition - quality - properties - households - hospitals - hospital catering - nursing homes - ingredients - animal products - philippines - edible oils - edible fats - institutional households
Voedingsmiddelenanalyses van de Vakgroep Humane Voeding. Deel 10 Vis, schaal- en schelpdieren.
Hulshof, P.J.M. ; Bovenkamp, P. van de; Boogerd, L. ; Bos, J. ; Germing-Nouwen, C. ; Kosmeyer-Schuil, T. ; Berg, H. van den; Hollman, P.C.H. ; Vaessen, H.A.M.G. ; Katan, M.B. - \ 1990
Wageningen : Vakgroep Humane Voeding, Landbouwuniversiteit - ISBN 9789072407122 - 37
voedingsmiddelen - chemische samenstelling - vetten - oliën - bakoliën - bakvetten - boter - margarine - voedingswaarde - voedsel - voedselsamenstelling - kwaliteit - eigenschappen - huishoudens - ziekenhuizen - ziekenhuiscatering - verpleeghuizen - ingrediënten - dierlijke producten - ghana - filippijnen - spijsoliën - spijsvetten - institutionele huishoudens - foods - chemical composition - fats - oils - cooking oils - cooking fats - butter - nutritive value - food - food composition - quality - properties - households - hospitals - hospital catering - nursing homes - ingredients - animal products - philippines - edible oils - edible fats - institutional households
Voedingsmiddelenanalyses van de Vakgroep Humane Voeding. Deel IX Alfabetisch register voor de delen I-VIII.
Scholte, B.A. ; Willems, M.A. ; Katan, M.B. - \ 1987
Wageningen : Vakgroep Humane Voeding, Landbouwuniversiteit - ISBN 9789072407085 - 42
voedingsmiddelen - chemische samenstelling - vetten - oliën - bakoliën - bakvetten - boter - margarine - voedingswaarde - voedsel - voedselsamenstelling - kwaliteit - eigenschappen - huishoudens - ziekenhuizen - ziekenhuiscatering - verpleeghuizen - dierlijke producten - ingrediënten - ghana - filippijnen - spijsoliën - spijsvetten - institutionele huishoudens - foods - chemical composition - fats - oils - cooking oils - cooking fats - butter - nutritive value - food - food composition - quality - properties - households - hospitals - hospital catering - nursing homes - animal products - ingredients - philippines - edible oils - edible fats - institutional households
Voedingsmiddelenanalyses van de Vakgroep Humane Voeding en het Rijks-Kwaliteitsinstituut voor Land- en Tuinbouwproducten. Deel 8 Alternatieve voedingsmiddelen.
Willems, M.A.W. ; Graaf, T.W. de; Katan, M.B. ; Hollman, P.C.H. ; Staveren, W.A. van; Bovenkamp, P. van de - \ 1987
Wageningen : Vakgroep Humane Voeding, Landbouwuniversiteit - ISBN 9789072407078 - 66
voedingsmiddelen - chemische samenstelling - vetten - oliën - bakoliën - bakvetten - boter - margarine - voedingswaarde - voedsel - voedselsamenstelling - kwaliteit - eigenschappen - huishoudens - ziekenhuizen - ziekenhuiscatering - verpleeghuizen - dierlijke producten - ingrediënten - ghana - filippijnen - spijsoliën - spijsvetten - institutionele huishoudens - foods - chemical composition - fats - oils - cooking oils - cooking fats - butter - nutritive value - food - food composition - quality - properties - households - hospitals - hospital catering - nursing homes - animal products - ingredients - philippines - edible oils - edible fats - institutional households
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