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Summary: Starch‐based films incorporated with cellulose nanofibres (CNFs) were tested as packaging to improve the stability of cashew nut kernels (CNKs). CNKs were conditioned in four packings: commercial polyethylene film (PEF), starch film (CF), nanocomposite CHF (starch + CNFs from chemical hydrolysis) and nanocomposite EHF (starch + CNFs from enzymatic hydrolysis). Effect of the packaging methods on peroxides value (POV), acidity value (AV), weight gain (WG), water activity (Aw), hardness and colour properties of the CNKs was investigated. CNKs packed with CHF and EHF showed lower POV (0.91 and 0.92 meqperoxide/kgsample, respectively) after 21 days of storage than other packed (1.07–1.13 meqperoxide/kgsample) and unpacked samples (1.32 meqperoxide/kgsample). CNKs packaged with nanocomposites presented similar WG to samples packaged with PEF and lower values than unpackaged CNKs. Biodegradable nanocomposites films showed potential to be used as packaging for food product, being an effective material for extending oilseeds shelf life. [ABSTRACT FROM AUTHOR]

Cellulose nanofibers (CNFs) were isolated from banana peel bran via alkaline treatment followed by enzymatic treatment with xylanase. The influence of process conditions such as pH, temperature, and concentrations of the enzyme and substrate on the properties of the CNFs was evaluated with a 2 4−1 fractional factorial design with three central points. Enzyme at 70 U/g of bran, substrate at 15%, pH 6.0, and temperature between 35 and 55 °C favored enzymatic hydrolysis. Transmission electron microscopy (TEM) images confirmed that treatment with xylanase effectively isolated cellulose fibers at the nanometer scale. Fourier transform infrared spectroscopy (FTIR) showed that a fraction of amorphous compounds was removed. X-ray diffraction revealed that the CNFs presented high crystallinity index (66.2%). The CNFs had a diameter of 3.7 nm, their aspect ratio was in the range of long nanofibers, and their suspension was stable (−29.1 mV). These features make the CNFs potentially applicable as reinforcing agents in composites. The results evidenced that enzymatic hydrolysis with xylanase successfully afforded CNFs from banana peel, a residue that constitutes a potential source of biodegradable materials of commercial interest. [ABSTRACT FROM AUTHOR]

The aim of this study was to verify the viability of lignocellulosic substrates to obtain renewable energy source, through characterization of the cellulolytic complex, which was obtained by solid state fermentation using Trichoderma viride. Enzymatic activity of the cellulosic complex was measured during saccharification of substrates filter paper, eucalyptus sawdust, and corncob, and compared with the activity of commercial cellulase. The characterization of the enzymes was performed by a 22 Full Factorial Design, where the pH and temperature were the variables of study. Enzymatic saccharification of different substrates appearedviable until 12 to be viable until 12 h; after this period the activity decreased for both enzymatic forms (cellulolytic complex and commercial cellulase). The enzymatic activity of the commercial cellulase was favored with the use of corncob as substrate, while the cellulolytic complex does not show any difference in its specificity by the substrates studied. The largest activities of both enzymes were obtained in the temperature and pH range between 40°C and 50°C and 4.8 and 5.2, respectively. The cellulolytic complex obtained appeared to be viable for the saccharification of lignocellulosic residues compared with the commercial cellulase. [ABSTRACT FROM AUTHOR]

Cellulose nanofibers were isolated from banana peel bran using chemical treatment (CT—alkaline treatment, bleaching, and acid hydrolysis) and enzymatic treatment (ET—alkaline treatment and hydrolysis with xylanase). Both bran and cellulose nanofibers were characterized by size distribution, X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR); the morphological features of the bran and the nanostructures were studied by scanning (SEM) and transmission electron microscopy (TEM), respectively. TEM analysis evidenced that both treatments effectively isolated banana fibers in the nanometer scale. Nanofibers originating from CT and ET had an average diameter of 10.9 and 7.6 nm and a length of 454.9 and 2889.7 nm, respectively. The aspect ratio of all the samples lay in the range of long fibers. In neutral water, the nanofiber suspensions exhibited high and negative zeta potential, which prevented the nanofibers from aggregating and yielded a more stable colloidal suspension. XRD studies revealed that CT afforded more crystalline cellulose nanofibers (58.6%) as compared with ET (49.2%). FTIR confirmed that the treatments removed most of the hemicelluloses and lignin present in the banana fibers. Nanoparticles isolated from the banana peel by both treatments have potential application as reinforcing elements in composites. [ABSTRACT FROM AUTHOR]

Cellulose nanofibers were isolated from banana peel bran using chemical treatment (CT—alkaline treatment, bleaching, and acid hydrolysis) and enzymatic treatment (ET—alkaline treatment and hydrolysis with xylanase). Both bran and cellulose nanofibers were characterized by size distribution, X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR); the morphological features of the bran and the nanostructures were studied by scanning (SEM) and transmission electron microscopy (TEM), respectively. TEM analysis evidenced that both treatments effectively isolated banana fibers in the nanometer scale. Nanofibers originating from CT and ET had an average diameter of 10.9 and 7.6 nm and a length of 454.9 and 2889.7 nm, respectively. The aspect ratio of all the samples lay in the range of long fibers. In neutral water, the nanofiber suspensions exhibited high and negative zeta potential, which prevented the nanofibers from aggregating and yielded a more stable colloidal suspension. XRD studies revealed that CT afforded more crystalline cellulose nanofibers (58.6%) as compared with ET (49.2%). FTIR confirmed that the treatments removed most of the hemicelluloses and lignin present in the banana fibers. Nanoparticles isolated from the banana peel by both treatments have potential application as reinforcing elements in composites. [ABSTRACT FROM AUTHOR]

• Lipid digestion rate of Pickering emulsions was studied using an in vitro digestibility protocol. • Emulsion properties during in vitro digestion were modulated according to the particle nature. • Tween 80, CCrys and CNFs were able to inhibit lipid digestion. • Chitosan-stabilized Pickering emulsions presented delayed lipid hydrolysis. • Relevant aspects about the interfacial design of food Pickering emulsions were elucidated. An in vitro digestibility protocol was used to elucidate the role of different emulsifying polysaccharides particles on the lipid digestion rate of oil-in-water Pickering emulsions. Emulsions stabilized by cellulose crystals (CCrys), cellulose nanofibers (CNFs), chitosan particles and a conventional emulsifier (Tween 80) were evaluated concerning microstructure, droplet size, zeta potential and free fatty acids released during digestion. After gastric step, the high positive charge of chitosan-stabilized emulsions favored the droplets disaggregation resulting in a mild effect of bridging flocculation by particles sharing and displacement of the size curve distribution toward lower size. After passing through the intestinal condition, these emulsions presented few droplets and chitosan aggregates with a monomodal size distribution and high mean droplet size (D 4,3 = 197 ± 8 μm). On the other hand, Tween 80, CCrys and CNFs were able to inhibit lipid digestion and no changes on mean droplet size were observed following intestinal step. CNFs-stabilized emulsion showed the lowest lipid digestion, whereas the strong adherence of the CCrys particles onto the droplet interface became them resistant to displacement by surface-active components (i.e. bile salts and lipase enzyme). On the other hand, a slow lipid hydrolysis could be observed in chitosan-stabilized emulsions promoted by competition between chitosan aggregates and intestinal fluids by the oil droplet interface. Studying the emulsions stabilized using different polysaccharides particles on gastrointestinal conditions we could elucidate important features for their potential application as control systems of lipid digestion rate, as well as, as delivery systems of lipophilic compounds. [ABSTRACT FROM AUTHOR]