Functional Properties of Pork Liver Protein Fractions

The functional (emulsifying, gelling and foaming) properties of liver protein fractions as well as their molecular weight distribution and surface hydrophobicity were investigated and compared to commercial proteins. Two protein fractions were characterized: water soluble (WSLP) and WSLP combined with salt soluble liver proteins (W?+?SSLP). The effect of salt concentrations was also investigated (0, 1.8 and 3.4 % NaCl). Both WSLP and W?+?SSLP displayed good emulsifying properties and foam stability. However, their gelling properties were rather poor. An increase in salt concentration decreased the emulsifying properties of WSLP while the effect on W?+?SSLP was less pronounced. Addition of 1.8 % NaCl increased foaming ability of WSLP and W?+?SSLP while foam stability was not affected. Further increase of NaCl (3.4 %) decreased both foaming ability and foam stability and is probably attributed to refolding of the protein molecules because of the higher level of hydrophobic groups with 3.4 % NaCl. Gel forming ability of WSLP and W?+?SSLP containing 0 % was higher compared to high salt concentrations. However, higher salt concentrations shifted onset gelation temperature of WSLP and W?+?SSLP to lower temperatures probably due to partial unfolding of the proteins as indicated by an increase of the surface hydrophobicity.     

Effect of stabiliser classes (animal proteins,vegetable proteins,starches, hydrocolloids and dietary fibre) on the physicochemical properties of a model lean meat product

The effects of eleven ingredients (originating from various ingredient classes: animal proteins, plant proteins, starches, hydrocolloids and fibres) applied in two different concentrations on drip loss, rheological characteristics and hardness were evaluated in a lean meat model system. The high concentration of potato starch, insoluble citrus fibre, rice starch or pea protein significantly (P < 0.05) reduced drip losses (6.92%, 17.87%, 15.70%, 17.60%, respectively) compared to control (30.80%), while rheological measures and hardness remained unchanged (P > 0.05). Moreover, the addition of low concentrations of soluble citrus fibre did not significantly affect hardness (4.11 N), whereas its inclusion at high concentrations had a significant effect on the final hardness (7.17 N). Among all the tested ingredients, xanthan presented the lowest drip loss value (0.12% and 0.40% for high and low concentration, respectively). Finally, gelatine did not show any differences in water holding capacity, storage modulus nor hardness compared with the control group.     

Characterisation and optimisation of individual wastewater treatment systems

Onsite individual wastewater treatment systems can provide a financially attractive alternative to a sewer connection in locations far from the existing sewer network. These systems are, however, relatively new, and practical experiences, especially long-term field studies, are lacking. Therefore, a thorough study of two compact biofilm-based, aerobic onsite systems, both of five population equivalents, was started in 2001. The assessment of the treatment performance of these systems, as well as the maintenance requirements and the characterisation of the feed are of great importance for the better understanding of the systems in order to optimise their design and performance. This paper presents an evaluation and discussion of the start-up and a starvation period of the two studied systems, followed by a characterisation of the incoming wastewater using activated sludge respirometry experiments in the context of the assessment and improvement of the denitrification process. Individual wastewater treatment systems are characterised by a rather long start-up period of 70-120 days. An important characteristic during the start-up is the nitrite peak, which indicates the initiation of the nitrification process. The respirometric experiments reveal that the failing denitrification is probably caused by an insufficient amount of readily biodegradable COD in the influent.     

Water‐based polyurethane dispersions

A general overview is presented of the most relevant and commercially available aqueous polyurethane dispersions (PUDs) and their typical properties. This paper starts with the chemistry and the general composition of standard PUDs and subsequently urethane–acrylic hybrid dispersions are presented with special emphasis on the relation between the obtained morphology and the final material properties. In a section regarding crosslinkable PUDs, the two most frequently applied curing mechanisms are mentioned: firstly the introduction of carbonyl groups into PUDs which can be used for curing at room temperature with amino functional compounds by formation of azomethine moieties, and secondly the introduction of unsaturated fatty acid moieties into PUDs, which enable oxidative curing at ambient conditions. The paper then continues with a section on UV‐curable, acryloyl‐functional PUDs, followed by a section on an interesting new development, namely water‐based polyurethanes with special optic and haptic properties. The paper ends with a section on recently reported modifications of PUDs, including carbon nanotube‐ and graphene‐modified PUDs, PUDs modified with silane coupling agents and PUDs modified with biodegradable moieties. © 2018 Society of Chemical Industry     

Toward geometrical design improvement of membraneless fuel cells: Numerical study

In this paper, the geometry and operation of membraneless laminar flow-based fuel-cells (LFFC) is analyzed. Three different fuel cell geometries are studied, these are: the conventional rectangular cell, a cylindrical cell and a star shaped cell. The geometries are derived from the principle of design of increasing the effective area of cathode while conserving the same volume-to-length ratio. Since the mixing and depletion widths are major factors that determine the cell performance, maximum Reynolds and Péclet numbers as well as fuel utilization are considered as variables of comparison. Furthermore, electrical characteristics as current density and total extracted current have been considered as well. Using finite element simulations, it is shown that for a HCOOH−O₂ cell, improved fuel utilization of 89% and 68.2% can be obtained with star and cylindrical geometries respectively, in comparison to conventional rectangular geometry (42.4%). Moreover, the total extracted current is also improved, reaching percentages greater than 1200% and 400% for the star and cylindrical designs respectively. It is shown that moving liquid–liquid interface, it is possible to further increase the current density of the designs and therefore the total extracted current.     

Effect of Fermentation and Drying on Procyanidins, Antiradical Activity and Reducing Properties of Cocoa Beans

This work was aimed to determine the effect of fermentation and drying on the content and profile of procyanidins (from monomers P1 to polymers P10) as well as on the antiradical and scavenging properties of cocoa beans. To this purpose, three experiments were carried out: a traditional fermentation process followed by air drying and two pilot-scale fermentation processes by either natural microbiota or starter followed by sun drying. Procyanidins were evaluated by HPLC analysis, while the total polyphenol index (TPI), the antiradical activity as well as the reducing power were determined by means of the reaction with the Folin–Ciocalteu reagent, the decolorization assays of the ABTS radical (TEAC) and the Ferric Reducing Antioxidant Power (FRAP) methods, respectively. Both the traditional and pilot-scale processes resulted to affect the profile and content of the procyanidins fractions as well as the antiradical and reducing power functionality. Drying caused a severe reduction of compounds and thus resulted to be the critical step for the loss of procyanidins and monomers in particular. The indices of functionality generally showed a decreasing trend as a consequence of processing, and their evolution was similar to that observed in procyanidins content. To study the relationship between the individual procyanidins and the antioxidant activity expressed as TEAC, FRAP and TPI, the data set were processed by modified partial least squares regression. The obtained models presented a good predictive ability. Normalised regression coefficients showed that the relative contribution of each single class of compounds to total antioxidant activity resulted as follows: P1?>?P2?>?P3?>?P4?>?P6?>?P8?>?P5?>?P7?>?P9?>>?P10.