3-D printed meat alternatives based on pea and single cell proteins and hydrocolloids: effect of paste formulation on process-induced fibre alignment and structural and textural properties

Extrusion-based 3D food printing can be used as an alternative structuring technique to traditional extrusion processing for creating meat-like structures. This study focused on 3-D food printing to generate structures analogous to meat by using various combinations of texturized pea protein fibrils, microbial Single Cell Protein (SCP) and hydrocolloids locust bean gum and/or sodium alginate. Simple moulding was utilized as benchmarking to better understand the 3D printing-induced structural effects. To gain understanding of the interactions between proteins of different origin (plant and SCP) and with hydrocolloids, structural, textural and rheological properties were analysed. Oscillatory stress sweeps of all printing pastes revealed elastic-dominant rheological behaviour (G’ 4000-6000 Pa) with a defined yield stress (25-60 Pa) explaining their printability and shape stability. X-ray microtomography of ion-crosslinked analogues showed a printing-induced preferential alignment of fibrils in the direction of nozzle movement, while moulding led to a random orientation. Textural characterization via bi-directional cutting tests demonstrated higher cutting force in transversal (FT) over longitudinal (FL) direction in 3D-printed samples and equal forces in moulded samples. The anisotropy index (AI=FT/FL) of printed samples ranged between 1.4-2.5, indicating anisotropic texture, and 0.8-1 for moulded samples indicating isotropic texture. This study demonstrated the applicability of paste-extrusion in generating anisotropic structures analogous to meat by process-induced fibril alignment. The results support further development of 3D food printing technology in design of sustainable meat alternatives resembling whole-muscle meat

Development and Consumer Perception of a Snack Machine Producing Customized Spoonable and Drinkable Products Enriched in Dietary Fiber and Protein

The aim of the study was to evaluate consumer perceptions toward customized snacks produced with a Healthy Snack Machine (HSM) prototype, at-site of the purchase and consumption. The present study had a multi-disciplinary approach including both snack product and HSM development (hardware and user interface). Snack development included both instrumental (viscosity, colloidal stability) and sensory characterization (by trained sensory (N = 10) and consumer (N = 55) panels) of spoonable and drinkable, oat- and dairy-based snack products, fortified with protein and/or dietary fiber. The protein and fiber addition reduced viscosity in spoonable products but did not affect the consistency of drinkable samples. Oat-based samples differed from dairy-based in multiple attributes in sensory profiling. In consumer sample testing, sample odor and taste were the most and least preferred aspects, respectively. In the snack machine testing, a qualitative consumer study (N = 33) showed that the HSM was easy to use, the user interface was clear, the ordering process was quick, and the participants were interested in using the HSM in the future. The snack choices (spoonable/drinkable and dairy/oat base) made by the consumers were distributed equally, but the berry-flavor was preferred over cocoa and vanilla. The most common HSM usage scenarios were “between work/school and hobbies” and “in transit from one place to another”

An ocean-colour time series for use in climate studies: the experience of the ocean-colour climate change initiate (OC-CCI)

Ocean colour is recognised as an Essential Climate Variable (ECV) by the Global Climate Observing System (GCOS); and spectrally-resolved water-leaving radiances (or remote-sensing reflectances) in the visible domain, and chlorophyll-a concentration are identified as required ECV products. Time series of the products at the global scale and at high spatial resolution, derived from ocean-colour data, are key to studying the dynamics of phytoplankton at seasonal and inter-annual scales; their role in marine biogeochemistry; the global carbon cycle; the modulation of how phytoplankton distribute solar-induced heat in the upper layers of the ocean; and the response of the marine ecosystem to climate variability and change. However, generating a long time series of these products from ocean colour data is not a trivial task: algorithms that are best suited for climate studies have to be selected from a number that are available for atmospheric correction of the satellite signal and for retrieval of chlorophyll-a concentration; since satellites have a finite life span, data from multiple sensors have to be merged to create a single time series, and any uncorrected inter-sensor biases could introduce artefacts in the series, e.g., different sensors monitor radiances at different wavebands such that producing a consistent time series of reflectances is not straightforward. Another requirement is that the products have to be validated against in situ observations. Furthermore, the uncertainties in the products have to be quantified, ideally on a pixel-by-pixel basis, to facilitate applications and interpretations that are consistent with the quality of the data. This paper outlines an approach that was adopted for generating an ocean-colour time series for climate studies, using data from the MERIS (MEdium spectral Resolution Imaging Spectrometer) sensor of the European Space Agency; the SeaWiFS (Sea viewingWide-Field-of-view Sensor) and MODIS-Aqua (Moderate-resolution Imaging Spectroradiometer-Aqua) sensors from the National Aeronautics and Space Administration (USA); and VIIRS (Visible and Infrared Imaging Radiometer Suite) from the National Oceanic and Atmospheric Administration (USA). The time series now covers the period from late 1997 to end of 2018. To ensure that the products meet, as well as possible, the requirements of the user community, marine-ecosystem modellers, and remote-sensing scientists were consulted at the outset on their immediate and longer-term requirements as well as on their expectations of ocean-colour data for use in climate research. Taking the user requirements into account, a series of objective criteria were established, against which available algorithms for processing ocean-colour data were evaluated and ranked. The algorithms that performed best with respect to the climate user requirements were selected to process data from the satellite sensors. Remote-sensing reflectance data from MODIS-Aqua, MERIS, and VIIRS were band-shifted to match the wavebands of SeaWiFS. Overlapping data were used to correct for mean biases between sensors at every pixel. The remote-sensing reflectance data derived from the sensors were merged, and the selected in-water algorithm was applied to the merged data to generate maps of chlorophyll concentration, inherent optical properties at SeaWiFS wavelengths, and the diffuse attenuation coefficient at 490 nm. The merged products were validated against in situ observations. The uncertainties established on the basis of comparisons with in situ data were combined with an optical classification of the remote-sensing reflectance data using a fuzzy-logic approach, and were used to generate uncertainties (root mean square difference and bias) for each product at each pixel

Novel Functional Bakery Ingredients with Fermentation of Cereal Raw Materials

There is increasing demand for functional ‘clean label’ bakery ingredients for extending shelf life of baked products. The literature review introduces physical (staling) and microbiological spoilage of wheat bread and current methods of their control. In addition, wheat sourdough fermentation with an emphasis on antifungal (AF) and dextran-producing lactic acid bacteria (LAB) starters as a ‘clean label’ alternative to chemical preservatives and hydrocolloid additives is reviewed. The aims of this study were to 1) Isolate and select promising antifungal or dextran-producing LAB strains, 2) Optimise dextran production in a cereal ingredient medium (CIM), produce prototype bakery ingredients under optimised conditions and to study their effects on wheat bread quality, 3) Investigate in vitro AF activity of strains cultivated in a CIM. The effects of fermentation time (16 – 32 h), CIM (8-14% w/v) and sucrose content (4 – 14% w/v) on viscosity and dextran production by the best Weissella strain were modelled using response-surface methodology. Moreover, cell growth, acidification, and oligosaccharide (OS) production during fermentations were determined. Further, the effects of enzyme treatment and longer fermentation time (40 – 72 h) were studied. Crumb firming during storage (0 – 4 days), the specific volume and acidity of wheat bread supplemented with fermented CIMs (5 – 10% flour weight) were measured. The AF activities of Lactobacillus-fermented CIM against a Penicillium spp. indicator mould was measured by agar diffusion assay. Under the optimal conditions (32 h at 25°C; 10% w/v CIM; 14% w/v sucrose) the best Weissella strain increased viscosity of the CIM significantly and produced technologically significant amounts of dextran (3.5% w/v) with simultaneous OS formation. At 5% of flour weight, dextran-enriched CIM increased loaf specific volume by 5% and gave 14% softer bread loaves of mild acidity after 4 days of storage compared to control wheat bread (P < 0.05). At 10% of flour weight, dextran-enriched CIM reduced loaf volume and increased crumb hardness. AF activity by Lactobacillus strains was detected only when cultivated in deMan-Rogosa-Sharpe (MRS) media but not in the CIM. AF activity could be enhanced by supplementing CIM with the MRS media component sodium acetate. Hence, sodium acetate at low pH appeared to be the main contributor to the AF activity of Lactobacillus strains. The dextran-enriched CIM is a promising baking ingredient for increasing the physical shelf life of wheat bread

Role of Mass Transport in Electrochemical CO2 Reduction to Methanol Using Immobilized Cobalt Phthalocyanine.

Electrochemical CO2 reduction (CO2R) using heterogenized molecular catalysts usually yields 2-electron reduction products (CO, formate). Recently, it has been reported that certain preparations of immobilized cobalt phthalocyanine (CoPc) produce methanol (MeOH), a 6-electron reduction product. Here, we demonstrate the significant role of intermediate mass transport in CoPc selectivity to methanol. We first developed a simple, physically mixed, polymer (and polyfluoroalkyl, PFAS)-free preparation of CoPc on multiwalled carbon nanotubes (MWCNTs) which can be integrated onto Au electrodes using a poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) adhesion layer. After optimization of catalyst preparation and loading, methanol Faradaic efficiencies and partial current densities of 36% (±3%) and 3.8 (±0.5) mA cm-2, respectively, are achieved in the CO2-saturated aqueous electrolyte. The electrolyte flow rate has a large effect. A linear flow velocity of 8.5 cm/min produces the highest MeOH selectivity, with higher flow rates increasing CO selectivity and lower flow rates increasing the hydrogen evolution reaction, suggesting that CO is an unbound intermediate. Using a continuum multiphysics model assuming CO is the intermediate, we show qualitative agreement with the optimal inlet flow rate. Polymer binders were not required to achieve a high Faradaic efficiency for methanol using CoPc and MWCNTs. We also investigated the role of formaldehyde as an intermediate and the role of strain, but definitive conclusions could not be established

Approved by: BEHAVIOR ISOLATION IN ENTERPRISE SYSTEMS

To my mother and father who made me what I am today. To my wife who stood by me every step of the way. To everyone who gave me a piece of advice along the way. Without all of you, I would not be here today. iii ACKNOWLEDGEMENTS This work was made possible by support and advice from many other individuals. In this section, I will try to acknowledge every one of them. Please forgive me if I forgot anyone, I am still grateful for your help. My advisor Karsten Schwan gets the lion’s share. With lots of support and advice and plenty of hand holding in the beginning that gradually transitioned to support and guidance as I matured as a researcher. It would be an understatement to say this work would not have been possible without his help and support. I am also grateful to my thesis committee, their valuable feedback on my thesis proposal helped formulate a solid plan of attack to build a strong dissertation and provided a wealth of feedback that was instrumental in the writeu