Recent Developments and Formulations for Hydrophobic Modification of Carrageenan Bionanocomposites

Versatility of the anionic algal polysaccharide carrageenan has long been discussed and explored, especially for their affinity towards water molecules. While this feature is advantageous in certain applications such as water remediation, wound healing, etc., the usefulness of this biopolymer is extremely limited when it comes to applications such as food packaging. Scientists around the globe are carrying out research works on venturing diverse methods to integrate hydrophobic nature into these polysaccharides without compromising their other functionalities. Considering these foregoing studies, this review is designed to have an in-depth understanding of diverse methods and techniques adopted for tuning the hydrophobic nature of carrageenan-based bionanocomposites, both via surface alterations or by changes made to their chemical structure and attached functional groups. This review article mainly focuses on how the hydrophobicity of carrageenan bionanocomposites varies as a function of the type and refinement of carrageenan, and with the incorporation of additives including plasticisers, nanofillers, bioactive agents, etc. Incorporation of nanofillers such as polysaccharide-based nanoparticles, nanoclays, bioceramic and mineral based nanoparticles, carbon dots and nanotubes, metal oxide nanoparticles, etc., along with their synergistic effects in hybrid bionanocomposites are also dealt with in this comprehensive review article

Thermo-mechanical processing of sugar beet pulp. II. Thermal and rheological properties of thermoplastic SBP

Thermoplastic properties of extruded sugar beet pulp (SBP) are closely linked to water–polymer relationships. DSC analyses of water evaporation, water fusion and biopolymer relaxation according to SBP moisture content gave a more accurate estimation of SBP hydration steps than classical water adsorption isotherm. Three moisture contents (8%, 26%, 41% db) were then defined as limits of the different hydration behaviours. Melt viscosity measurements of SBP showed its shear thinning behaviour and the measured apparent viscosity is in the same range as thermoplastic starch viscosity. Using only water as plasticizer, to one temperature corresponded one moisture content to reach the optimal flowing properties: 110°C/35%, 120°C/25% and 130°C/20%. This "plasticization" temperature has been estimated through DSC measurements of large amounts of moistened SBP in pressure-resistant pans. This new kind of DSC measurement revealed a new sample mass dependent second order transition between 140 and 180°C, which temperature is linearly linked to the sample mass

A review of current and future food applications of natural hydrocolloids

The main aim of this review paper was to focus on current and potential future sources and food applications of natural hydrocolloids in the food industry. The emerging research trends, problems, new methods and alternative approaches in production, environmental concerns, market trends and newly discovered health benefits have been discussed for natural hydrocolloids of commercial relevance. The rheological and surface active properties, interactions, functional properties, films and coatings, encapsulation applications and nanotechnology uses of natural hydrocolloids have been discussed in the light of recent developments. This review also reflected the most up-to-date concepts of applying natural hydrocolloids to meet consumer's and food sector's sophisticated demands related to food products

Detailed analysis of the composition of selected plastic packaging waste products and its implications for mechanical and thermochemical recycling

Plastic packaging typically consists of a mixture of polymers and contains a whole range of components, such as paper, organic residue, halogens, and metals, which pose problems during recycling. Nevertheless, until today, limited detailed data are available on the full polymer composition of plastic packaging waste taking into account the separable packaging parts present in a certain waste stream, nor on their quantitative levels of (elemental) impurities. This paper therefore presents an unprecedented indepth analysis of the polymer and elemental composition, including C, H, N, S, O, metals, and halogens, of commonly generated plastic packaging waste streams in European sorting facilities. Various analytical techniques are applied, including Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), polarized optical microscopy, ion chromatography, and inductively coupled plasma optical emission spectrometry (ICP-OES), on more than 100 different plastic packaging products, which are all separated into their different packaging subcomponents (e.g., a bottle into the bottle itself, the cap, and the label). Our results show that certain waste streams consist of mixtures of up to nine different polymers and contain various elements of the periodic table, in particular metals such as Ca, Al, Na, Zn, and Fe and halogens like CI and F, occurring in concentrations between 1 and 3000 ppm. As discussed in the paper, both polymer and elemental impurities impede in many cases closed-loop recycling and require advanced pretreatment steps, increasing the overall recycling cost

Fully Integrated Biochip Platforms for Advanced Healthcare

Recent advances in microelectronics and biosensors are enabling developments of innovative biochips for advanced healthcare by providing fully integrated platforms for continuous monitoring of a large set of human disease biomarkers. Continuous monitoring of several human metabolites can be addressed by using fully integrated and minimally invasive devices located in the sub-cutis, typically in the peritoneal region. This extends the techniques of continuous monitoring of glucose currently being pursued with diabetic patients. However, several issues have to be considered in order to succeed in developing fully integrated and minimally invasive implantable devices. These innovative devices require a high-degree of integration, minimal invasive surgery, long-term biocompatibility, security and privacy in data transmission, high reliability, high reproducibility, high specificity, low detection limit and high sensitivity. Recent advances in the field have already proposed possible solutions for several of these issues. The aim of the present paper is to present a broad spectrum of recent results and to propose future directions of development in order to obtain fully implantable systems for the continuous monitoring of the human metabolism in advanced healthcare applications

Bioactive Gelatin-based Date By-Product for Packaging Applications: Physico-Chemical and Biological Characterization

 Biodegradable films from gelatin (Gn) with various date by-product (DBP) concentrations (1, 2, 3 and 4 wt %) were prepared. Elaborated films were examined in terms of physical properties (thickness, density, water solubility, water content, degree of swelling, color), and antimicrobial properties (Escherichia coli and Staphylcoccus aureus). Adding the highest concentration of DBP (4%), resulted an increase in the WHC of film as compared with control film. Moreover, the incorporation of 1% DBP reduced the moisture level of Gn based composite films as compared with the control film. Furthermore, Film with 4% of DBP had the lowest solubility which reached 39.39%. Incorporation of DBP from 1 to 4% showed decrease of L- and a-values. The active Gn-DBP 1% showed less lightness as compared to Gn-DBP 3%. The incorporation of DBP into film-forming solutions led to increased opaqueness for all gelatin-based composite films. The calculated opacity value was inversely proportional to transparency. Moreover, the Active Gn-DBP 1% and 2% film presented effective antibacterial activity against bacteria such as Staphylococcus aureus and Escherichia coli. The results showed an enhancement in the biodegradability of Gn-DBP films in moist soil. The results reveal the benefits of date by-products incorporated into gelatin based films as a potential material for active food packaging.&nbsp

Value chains as a linking-pin framework for exploring governance and innovation in nano-involved sectors: illustrated for nanotechnologies and the food packaging sector

Consultable sur Internet : http://ejlt.org//article/view/104/180International audienceNanotechnology is often referred to as an entity in itself, a promising technoscience that may enable a vast array of products that will affect and change society. Looking beneath the umbrella-term of "nanotechnology" what is actually occurring with regards to the emergence of product/applications? And what does this mean for governance of emerging nano-involved product development and societal uptake?. The article argues that one must move beyond the broad umbrella term of nanotechnology to explore governance challenges. It posits that for exploring governance of nano-applications, a much ignored level of analysis - the industrial value chain - is a promising level of analysis in both identifying the current activities and potential impacts of nanotechnology and the modes of governance that are in play, how they evolve and how they could be shaped. Focusing on value chains is important for the near and mid-term in order to evaluate and characterise the smorgasbord of techno-scientific promises stemming from nanotechnology and the effects of broader sectoral changes on potential nano-enabled products that may reach citizen-consumers. As nanotechnology enters various parts of the agrifood sector, the emerging governance arrangements of nanotechnology meet incumbent (and still developing) governance regimes, consumer positions and actor arrangements. The paper further articulates this claim, closing with an outlook on what sort of approaches could be used for foresighting potential developments in nanotechnology, their impacts and potential frameworks for exploring and modulating nanotechnology governance

Biocomposites based on poly(butylene succinate) and curaua: Mechanical and morphological properties

Abstract Biocomposites based on poly(butylene succinate) (PBS) and curaua fibers have been produced by compression molding, and investigated as a function of fiber length and amount. Mechanical tests, water uptake and morphology studies were carried out in order to assess the composite features according to the characteristics of the reinforcing agents. It turns out that the impact and flexural strengths increase with fiber content. Moreover, the fiber length, varying from 1 to 4 cm for the composite reinforced with 20 wt% of fiber, influences impact strength, which is higher for shorter than for longer fibers. However, flexural strength is not greatly influenced by the length of the fibers. Water uptake studies reveal a higher sensitivity of the material to fiber content rather than fiber size. Biocomposites, which are characterized by enhanced mechanical properties as compared to PBS, can have different applications, for example in rigid packaging or interior car parts