Mealworm Products with Custom-made Texture

Due to the environmental impact of animal meat such as beef, pork and poultry, a need for alternative protein sources and meat substitutes is growing. Insects seem to provide the optimal alternative

Hoe krijg je een vezelachtige structuur? : Technologie bij het maken van eiwitrijke producten

Voor producenten is het een uitdaging om voedingsmiddelen met een hoog eiwitgehalte, zoals vegetarische producten, een vezelachtige structuur te geven. De gebruikte technologie heeft (naast de gebruikte eiwitten en andere ingrediënten) een bepalende invloed op de textuur van het halffabricaat of eindproduct

Succesfactoren kleinschalige bioraffinage : tussentijdse rapportage 2014

Economies of scale zijn een belangrijke belemmering voor de implementatie van kleinschalige processen. Dit wordt bijvoorbeeld geïllustreerd met schaalfactoren voor apparatuur en menskracht. Als er echter naar hele ketens wordt gekeken, zijn er wel duidelijke situaties waarin kleinschaligheid voordelen biedt. Dit wordt in dit rapport geïllustreerd aan de hand van voorbeeldcases, zowel uit de literatuur of aan de hand van informatie binnen de “PPS Kleinschalige Bioraffinage”

Succesfactoren kleinschalige bioraffinage : Tussentijdse rapportage 2015

Economies of scale zijn een belangrijke belemmering voor de implementatie van kleinschalige processen. Dit wordt bijvoorbeeld geïllustreerd met schaalfactoren voor apparatuur en menskracht. Als er naar hele ketens wordt gekeken, zijn er duidelijke situaties waarin kleinschaligheid voordelen biedt. Dit wordt in dit rapport geïllustreerd aan de hand van voorbeeldcases, zowel uit de literatuur of aan de hand van informatie binnen de “PPS Kleinschalige Bioraffinage” (voor meer informatie over de PPS zie: http://www.kleinschaligebioraffinage.nl/nl/kbr.htm). De PPS Kleinschalige Bioraffinage heeft in 2013 en 2014 een studie gedaan naar de succesfactoren van kleinschalige bioraffinage. Deze meer theoretische kennis is dit afgelopen jaar in de praktijk getoetst en toegepast. In samenspraak met de PPS deelnemers en de betrokken onderzoekers, zijn drie onderwerpen benoemd voor verdere studie: business cases, ontwateren en ketenanalyse. Daarmee is begin 2015 gestart. De businesscase van biet naar suiker is een uitgewerkt voorbeeld waar dankzij de kleinschaligheid energievoordelen te behalen zijn. Het ontwateren is besproken met slib als grondstof, aan de hand van een waterzuiverings-voorbeeld. Tenslotte is er een begin gemaakt met een ketenanalyse, waarbij kleinschalige bioraffinage is geïntegreerd in een agrarisch systeem

Succesfactoren kleine schaal

Onze maatschappij ondergaat momenteel de transitie van een op aardolie gebaseerde economie naar een biobased economy. Hiervoor worden vele nieuwe bioraffinage processen ontwikkeld. Kleine schaal bioraffinage kan voordelen hebben, niet alleen vanuit een sociaal een duurzaam oogpunt, maar ook puur economisch. Succesvolle voorbeelden zijn in dit rapport geanalyseerd en de drijfveren voor kleinschalige bioraffinage zijn verder uitgewerkt. Daarnaast is er gezocht naar een eenduidige definitie voor kleinschalige bioraffinage. Hier zijn specifieke getallen uitgekomen, maar nog geen generieke beschrijving

Biobased economy: de potentie van eiwitten voor technische toepassingen

Eiwitten zijn, behalve essentiële bouwstoffen voor mens en dier, tevens bruikbaar voor toepassingen in bijvoorbeeld shampoos, bioplastics, coatings of lijmen. In deze studie is een inventarisatie gemaakt van zowel de huidige beschikbare eiwitbronnen als de bronnen waar in de toekomst veel van verwacht wordt. Mits er voldoende efficiënt met grondstoffen wordt omgesprongen, kunnen voor zowel food als non-food toepassingen wereldwijd voldoende eiwitten worden geproduceerd. Het is wel belangrijk dat de eiwitten die door bioraffinage uit grondstoffen worden gehaald, hun unieke eigenschappen behouden

Hadron Polarizabilities and Form Factors

This is the summary of the working group on Hadron Polarizabilities and Form Factors of the Chiral Dynamics Workshop in Mainz, September 1-5, 1997.Comment: 21 pages LaTeX2e, uses epsf, 9 fig

Molecular characteristics of carbapenemase-producing Enterobacterales in the Netherlands; results of the 2014–2018 national laboratory surveillance

Objectives: Carbapenem resistance mediated by mobile genetic elements has emerged worldwide and has become a major public health threat. To gain insight into the molecular epidemiology of carbapenem resistance in The Netherlands, Dutch medical microbiology laboratories are requested to submit suspected carbapenemase-producing Enterobacterales (CPE) to the National Institute for Public Health and the Environment as part of a national surveillance system. Methods: Meropenem MICs and species identification were confirmed by E-test and MALDI-TOF and carbapenemase production was assessed by the Carbapenem Inactivation Method. Of all submitted CPE, one species/carbapenemase gene combination per person per year was subjected to next-generation sequencing (NGS). Results: In total, 1838 unique isolates were received between 2014 and 2018, of which 892 were unique CPE isolates with NGS data available. The predominant CPE species were Klebsiella pneumoniae (n = 388, 43%), Escherichia coli (n = 264, 30%) and Enterobacter cloacae complex (n = 116, 13%). Various carbapenemase alleles of the same carbapenemase gene resulted in different susceptibilities to meropenem and this effect varied between species. Analyses of NGS data showed variation of prevalence of carbapenemase alleles over time with blaOXA-48 being predominant (38%, 336/892), followed by blaNDM-1 (16%, 145/892). For the first time in the Netherlands, blaOXA-181, blaOXA-232 and blaVIM-4 were detected. The genetic background of K. pneumoniae and E. coli isolates was highly diverse. Conclusions: The CPE population in the Netherlands is diverse, suggesting multiple introductions. The predominant carbapenemase alleles are blaOXA-48 and blaNDM-1. There was a clear association between species, carbapenemase allele and susceptibility to meropenem

Anti-solvent crystallization for local sugar production : Demonstration plant bij YPSS Engineering at the Wageningen University Campus

At the beginning of the twentieth century there were more than 30 Sugar factories. Now there remain only two, one in Groningen (Hoogkerk) and the other in Noord-Brabant (Dinteloord). This means that beets must be transported over long distances. Transport costs make up about 50% of the total expenses of the beet refining process, even though transport has been optimized extensively. With the expected rise of energy prices, centralized processing will become significantly more expensive

Oligosaccharide production with thermophilic enzymes

The goal of the research reported in this thesis was to develop a process concept for the tailor made production of oligosaccharides. These specific non-digestible oligosaccharides can be used as prebiotics. They promote the growth of beneficial bacteria in the gastrointestinal (GI) tract. Commercial prebiotic oligosaccharides are often not pure oligosaccharides, but mixtures. In this thesis focus is on the production of oligosaccharides of higher purity.Our main interest was in a production process at elevated temperatures. This can have many advantages, amongst which is the possibility to increase the substrate concentration. We used a thermophilicβ-glycosidase from Pyrococcus furiosus . Enzymes from thermophilic microorganisms have unique characteristics such as high temperature-, chemical- and pH stability. Applications with thermophilic enzymes are summarised in chapter 2. The main advantages of performing processes at higher temperatures are the reduced risk of microbial contamination, lower viscosity, improved transfer rates and improved solubility of substrates. However, co-factors, substrates or products might be unstable or other side reactions may occur.One route of oligosaccharide production is the synthesis from monosaccharides or disaccharides, using glycosidases as a catalyst. Monosaccharides can be condensated to disaccharides and disaccharides can be transglycosylated to trisaccharides. To investigate the potential of this synthesis withβ-glycosidase fromPyrococcus furiosus we determined kinetic parameters for substrate conversion and product formation from cellobiose, lactose, glucose and galactose. The obtained parameters for initial rate measurements of disaccharide conversion were also used for the interpretation of experiments in time. The model for cellobiose gave a good description of the experiments. The enzyme was found to be uncompetitively inhibited by cellobiose and competitively inhibited by glucose. Lactose conversion however, could not be modelled satisfactorily; apparently additional reactions take place. Monosaccharide condensation also yielded oligosaccharides, but much slower. The use of a hyperthermostable enzyme was found to be positive. More substrate could be dissolved at higher temperatures, which benefited all reactions. This research is described in chapter 3.Besides the advantage of higher substrate solubility, temperature also influences enzyme kinetics. In chapter 4, the thermostable Pyrococcus furiosus-glycosidase was applied for oligosaccharide production from lactosein a kinetically controlled reaction. The experiments showed that higher temperatures are beneficial for the absolute as well as relative oligosaccharide yield.However, at reaction temperatures of 80°C and higher, the inactivation rate of the enzyme in the presence of sugars was increased by a factor 2, compared to the inactivation rate in the absence of sugars. This increased enzyme inactivation was caused by the occurrence of Maillard reactions between the sugar and the enzyme. The browning of our reaction mixture due to Maillard reactions was modelled by a cascade of a 0 thand 1 storder reaction and related to enzyme inactivation. From these results we conclude that modification of only a small number of amino-groups already gives complete inactivation of the enzyme.Reduction of Maillard reactions can be done by altering process conditions or through modification of the enzyme, either chemically or by altering the enzyme structure through genetic modifications. Chemical modification of the enzyme was studied. The enzyme was covalently immobilised on Eupergit. Unfortunately, the immobilisation did not reduce Maillard reactivity.Further reaction optimisation required a down-stream processing method for oligosaccharide separation. This was also essential for the production of a pure oligosaccharide product. Two methods for oligosaccharide purification are described in chapter 5.Oligosaccharides were produced in a condensation reaction using the -glycosidase from Pyrococcus furiosus. With a 60% (w/w) galactose solution as the substrate and oligosaccharide yield of 18% (w/w) was obtained. The feasibility of a Simulated Moving Bed (SMB) for downstream separation was investigated by modelling. The required parameters were determined experimentally with column experiments. The components could be separated with an SMB into a 91% pure product stream and a 99% pure galactose stream. This galactose stream can be recycled to the enzyme reactor. Also nanofiltration can be used for oligosaccharide purification. This system was also modelled and the results were compared to those that can be achieved with SMB.It is also possible to produce transgalacto-oligosaccharides in a more conventional way, with lactose as a substrate. Production is much cheaper when compared to a galactose-based process. Separation of oligosaccharides from this reaction via SMB was also studied.The size of all separation units is still considerably large and further optimisation is necessary to make a process for the production of specific high purity galacto-oligosaccharides cost-effective.Various aspects of the process are discussed further in chapter 6. Emphasis is on the specific influence of temperature on the process and on further optimisation of the downstream processing of oligosaccharides.</p