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关键词： 3D food printing   Spirulina   Chlorella   Printability   Cereal-based snack  

摘要： Microalgal biomass is a promising functional ingredient for innovative food products due to its potential health benefits given by its composition (protein, minerals, vitamins, pigments, fatty acids, sterol and antioxidants). However, in practice, the level of incorporation of microalgae in many products is limited due to among others the strong green colour. In this study, we investigated the potential of 3D food printing to incorporate microalgae in cereal *** vulgarisandArthrospira platensiswere the microalgae evaluated. First, the effect of microalgae fortification on both the rheological properties and printability of batters and on the properties of snacks (i.e. shape, texture and colour) was studied. Microalgae fortification improved the printability of batters using extrusion-based 3D printing, which was concluded from the increased extrusion force and shear modulus in comparison to those for the batter without microalgae. Subsequently, snacks enriched with 3% and 4%Chlorellaprovided most accurate printed structures. However, snacks with the latter levels of microalgae addition are probably not well accepted by consumers due to the strong green and dark colour of the cereal snacks after baking. The next logical step could be to use coaxial food printing to hide the microalgae inside the snack. First coaxial printing experiments showed that this could be a feasible approach.

关键词： amylopectin   amylose   cellulose   chitosan   sustainable  

摘要： Interest in starch-based films has increased precipitously in response to a growing demand for more sustainable and environmentally sourced food packaging materials. Starch is an optimal candidate for these applications given its ability to form thermoplastic materials and films with affordable and often sustainably sourced plasticizers like those produced as waste byproducts by biodiesel and agricultural industries. Starch is also globally ubiquitous, affordable, and environmentally benign. Although the process of producing starch films is relatively straightforward, numerous factors, including starch source, extraction method, film formulation, processing methods, and curing procedures, drastically impact the ultimate material properties. The significant strides made from 2015 to early 2020 toward elucidating how these variables can be leveraged to improve mechanical and barrier properties as well as the implementation of various additives or procedural modifications are cataloged in this review. Advances toward the development of functional films containing antioxidant, antibacterial, or spoilage indicating components to prevent or signal the degradation of food products are also discussed.

关键词： lanthanides   alkoxybenzoic acids   1   10-phenanthroline   complexes   luminescence  

摘要： New coordination compounds of terbium(III) and gadolinium(III) with alkoxybenzoic acids and 1,10-phenanthroline were prepared by the electrochemical synthesis method. The structure and some properties of the compounds synthesized were studied by IR spectroscopy and luminescence spectroscopy, as well as by thermogravimetry. Mixed-ligand complexes of terbium(III) were found to be thermally stable up to 250-300 degrees C, which enables their deposition by thermal vacuum evaporation in the production of electroluminescent devices. The triplet energy levels of the ligands were determined, and the influence of the neutral ligand on the luminescent properties of the terbium(III) coordination compounds was evaluated.

关键词： Brazilian fruits   Antioxidant capacity   Food analysis   Dietary fiber   Malic acid   Vitamin C  

摘要： Pouteria glomerata is a native species from the Brazilian Pantanal, whose fruit is edible and still underexploited. The objective of this study was to carried out the chemical, nutritional and antioxidant properties of this tropical fruit, as well as to isolate e characterize the chemical strucutre of their dietary fibers. DPPH and ORAC methods were used to determine the antioxidant capacity. Minerals were quantified using inductively coupled plasma optical emission spectrometry. Soluble and insoluble dietary fiber fractions were obtained by the standard enzymatic-gravimetric method and chemically characterized by monosaccharide composition, gel permeation and NMR spectroscopy. Results showed that P. glomerata fruits presented high antioxidant capacity and high levels of vitamin C, minerals, insoluble dietary fiber, and malic acid. The soluble dietary fiber was mainly composed of uronic acids, arabinose, and galactose, and NMR analysis indicated the presence of highly methylesterified homogalacturonan, arabinan and/or arabinogalactan as pectic polysaccharides. Hemicelluloses present in insoluble dietary fiber fraction were solubilized by alkaline treatment, and characterized as (1 -> 4)-beta-D-xylan. The results brings new chemical information about this native fruit and may open new opportunities for using it as a potential ingredient for health improvement by human comsumption.

关键词： electron beam irradiation   physicochemical properties   quinoa   starch  

摘要： Quinoa (Chenopodium quinoaWilld.) is treated with electron beam irradiation (EBI) at doses of 0, 1, 2, 4, and 8 kGy. The effects of EBI on physicochemical and structural properties are investigated. The mean size of quinoa granules and starch and the amylose content of quinoa increase as the irradiation dose increases. The storage and loss moduli of quinoa flour decline after irradiation. The swelling ability of quinoa flour does not significantly change within the irradiation dose between 0 and 4 kGy. The solubility of quinoa flour increases significantly when quinoa is irradiated at an irradiation dose of >4 kGy. Differential scanning calorimetry (DSC) results indicate that the changes in enthalpy significantly decrease after irradiation, whereas EBI does not significantly change other DSC parameters. All the viscosity parameters of quinoa flour in a Rapid Visco Analyzer significantly decline after EBI. X-ray diffraction reveals that the relative crystallinity of starch decreases after irradiation. Scanning electron microscopy shows that irradiation does not damage the microstructure of quinoa starch. The contents of slowly digestible and resistant starches of quinoa starch increase as the irradiation dose increases. Fourier transform infrared spectroscopy indicates that no new chemical groups in starch are formed.

关键词： Ethanol  

摘要： This work aims at investigating effect of different pretreatments and varied temperature on the drying kinetics, bioactive compounds, antioxidant activity, microstructure and functional group of apple slices using pulsed vacuum dryer. Pretreated apple slices (Ethanol, US + W, and US + E) dried at varied temperature (60, 70, and 80 degrees C) were analyzed to determine total phenolic content (TPC), total flavonoid content (TFC), 1,1-diphenyl-2-picrylhydrazyl (DPPH+), 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS(+)), color, microstructure and FT-IR spectroscopy. The findings revealed that US + E pretreatment significantly (p < .05) decreased drying time (20-33.33%). Activation energy and moisture effective diffusivity were 17.60-29.86 kJ/mol and 1.52-3.60 x 10(-8)m(2)/s, respectively. Microstructure evaluation showed disruption of cells structure and microchannels formation but was more prominent in US + E pretreatment with noticeable larger pores and several microchannels. US + E pretreatment retained TPC (64.89-75.75 mg/100 g GAE dw), TFC (45.96-56.25 mg/100 g ER dw), DPPH+(66.85-73.34%) and ABTS(+)(62.58-71.17%) than Ethanol, US + W, and control and was further corroborated by the observed peaks as revealed by the FT-IR spectroscopy. Color (L*,a*,b*, whiteness) was better retained by Ethanol and US + E pretreatments. US + E pretreatment decreased drying time and also preserved bioactive compounds, antioxidant activity and color of apple slices. Practical application Apples are popularly consumed fruits and confer various nutritional and health benefits to humans. Drying is the most common approach for apple processing and shelf life extension. However, drying often leads to a reduction in quality parameters as well as degradation of nutritional components of the apple. Novel pretreatment techniques like ultrasonic aided ethanolic pretreatment preceding to apple drying provides an added advantage over conventional drying methods in that it reduces deh

关键词： Dietary fiber   Nannochloropsis oceanica   Ultrasonic-assisted alkaline extraction   Physicochemical properties   Adsorption properties  

摘要： In this study, the process parameters were optimized for extracting soluble dietary fiber (U-SDF) from the residue of Nannochloropsis oceanica (NR) by ultrasonic-assisted alkaline extraction (UAE). The structure, physicochemical and functional properties of U-SDF, insoluble dietary fiber (U-IDF) extracted by UAE, and soluble dietary fiber (A-SDF) extracted by alkaline extraction were investigated. The results showed that the U-SDF yield (17.50 +/- 0.26%) under optimal conditions increased by 150.72% compared with A-SDF. U-SDF exposed more hydrophilic groups (such as -OH) and more loose structure in comparison with A-SDF and U-IDF. In addition, U-SDF had higher solubility, adsorption capacity of cholesterol, sodium cholate, ammonium nitrite and glucose, and digestive enzyme (a-amylase and pancreatic lipase) inhibition ability in vitro than A-SDF and U-IDF. However, U-SDF had lower water holding capacity, water swelling capacity, and oil holding capacity than U-IDF. Thus it was indicated that DF from NR was a potentially available functional food ingredient, which will increase the added value of N. oceanica.

关键词： Lignocellulosic material   Antioxidant   Bio-based   Films   Functional   Composite  

摘要： Organosolv lignin was incorporated in carboxymethyl cellulose (CMC)-based films as a reinforcing and bioactive agent. Films were produced by the casting method using compatible and environmentally friendly solvents. The incorporation of lignin in CMC-based films was evaluated in term of morphology, physicochemical, barrier, mechanical and antioxidant properties. Solubility tests showed that lignin improved the water resistance of the films for approx. 60%. This behavior was also observed for the water vapor permeability, achieving a 20% reduction. Morphological characteristics suggested low compatibility between organosolv lignin and CMC matrix, revealed by the small aggregates homogeneously distributed in the film, through scanning electron microscopy, related to the self-assembly behavior of lignin. CMC/lignin-based films also presented higher thermal stability. Fourier transform infrared spectroscopy showed that incorporation of lignin led to small changes in the film's structure. Finally, organosolv lignin proved to be a promising material for the development of active CMC-based films due to its demonstrated antioxidant activity that can be useful to pack food products that suffer from undesirable oxidation reactions.

关键词： Three-phase nanocomposites   EP   PU   ZnMn2O4 nanocomposites   RSM   CCD methods   mechanical properties   antibacterial properties  

摘要： Polymeric mixing and ultrasonic dispersion method as a green, fast, effective, and inexpensive technique was utilized to prepare epoxy/polyurethane/zinc manganite nanoparticles (EP/PU/ZnMn2O4 NPs) nanocomposites. The ZnMn2O4 NPs and PU were used for the optimization of mechanical properties of EP resin. Response surface methodology (RSM) coupled with central composite design (CCD) was employed to obtain suitable mathematical models as function of physico- and thermomechanical factors. The weight fractions of PU and ZnMn2O4 NPs were chosen as the independent variables, and the effect of these variables on the mechanical properties of the EP resin was investigated. The tensile test showed that the addition of the PU and ZnMn2O4 NPs in the polymer matrix improved the mechanical properties. The dynamic mechanical analysis results showed that the storage modulus and the glass transition temperatures of the nanocomposites increased and decreased, respectively. The optimum values of PU and ZnMn2O4 NPs contents for good mechanical properties were determined as 0.73 weight percentage (wt%) and 0.15 wt% ratio to EP resin, respectively. The antibacterial properties of the optimum sample were also investigated, and the results showed that, with the addition of the NPs, the antibacterial performance of EP/PU increased. The X-ray diffraction, Fourier-transform infrared, scanning electron microscopy/energy-dispersive X-ray analysis, diffuse reflectance spectroscopy (DRS), and vibrating sampler magnetmeter analyses were also applied to study the chemical and magnetic properties of the optimized nanocomposite samples.

关键词： Plastic pollution   Microplastics   Biodegradable plastic   Soil quality   Agricultural soil  

摘要： The plastic mulch films used in agriculture are considered to be a major source of the plastic residues found in soil. Mulching with low-density polyethylene (LDPE) is widely practiced and the resulting macro- and microscopic plastic residues in agricultural soil have aroused concerns for years. Over the past decades, a variety of biodegradable (Bio) plastics have been developed in the hope of reducing plastic contamination of the terrestrial ecosystem. However, the impact of these Bio plastics in agro-ecosystems have not been sufficiently studied. Therefore, we investigated the impact of macro (around 5 mm) and micro (<1 mm) sized plastic debris from LDPE and one type of starch-based Bio mulch film on soil physicochemical and hydrological properties. We used environmentally relevant concentrations of plastics, ranging from 0 to 2% (w/w), identified by field studies and literature review. We studied the effects of the plastic residue on a sandy soil for one month in a laboratory experiment. The bulk density, porosity, saturated hydraulic conductivity, field capacity and soil water repellency were altered significantly in the presence of the four kinds of plastic debris, while pH, electrical conductivity and aggregate stability were not substantially affected. Overall, our research provides clear experimental evidence that microplastics affect soil properties. The type, size and content of plastic debris as well as the interactions between these three factors played complex roles in the variations of the measured soil parameters. Living in a plastic era, it is crucial to conduct further interdisciplinary studies in order to have a comprehensive understanding of plastic debris in soil and agroecosystems. (c) 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/