Properties of native and oxidized corn starch/polystyrene blends under conditions of reactive extrusion using zinc octanoate as a catalyst

The selective adsorption mechanism of V-type starches for key off-odors of sea cucumber intestinal peptides

The off-odors of sea cucumber intestinal peptide (SCIP) severely limit its application. In this study, the V-type starches were derived from high amylose maize starch to adsorb odors of SCIP and the adsorption mechanism was explored. The inclusion complexes formed by V-type starches and volatile compounds of SCIP were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. The electronic nose results revealed a decreasing trend in response values of SCIP, with significant differences before and after deodorization (p < 0.05). Furthermore, 82 volatiles were identified from SCIP, and six were determined as key volatiles using gas chromatography-mass spectrometry. The V6- and V7-type starches with smaller cavity sizes selectively adsorb butyric acid, isobutyric acid and nonaldehyde, and V8-type starches with a larger cavity size selectively adsorb trimethylamine. This study proved that using V-type starches for deodorization could effectively improve SCIP flavor.

Potentially Health-Promoting Spaghetti-Type Pastas Based on Doubly Modified Corn Starch: Starch Oxidation via Wet Chemistry Followed by Organocatalytic Butyrylation Using Reactive Extrusion

Extruded spaghetti-type pasta systems were obtained separately either from native or oxidized starch prepared via wet chemistry with the aim of evaluating the effect of oxidation modification of starch. In addition to this, the butyrylation reaction (butyrate (Bu) esterification-short-chain fatty acid) using native or oxidized starch was analyzed under reactive extrusion (REx) conditions with and without the addition of a green food-grade organocatalyst (l(+)-tartaric acid) with the purpose of developing potentially health-promoting spaghetti-type pasta systems in terms of increasing its resistant starch (RS) values. These would be due to obtaining organocatalytic butyrylated starch or not, or the manufacture of a doubly modified starch (oxidized-butyrylated-starch oxidation followed by organocatalytic butyrylation) or not. To this end, six pasta systems were developed and characterized by solid-state ¹³C cross-polarization magic angle spinning nuclear magnetic resonance (CP MAS NMR) spectroscopy, degree of substitution (DS), attenuated total reflectance Fourier transform infrared (ATR/FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), pancreatic digestion, free Bu content analysis and in vitro starch digestibility. The results obtained here suggest that starch oxidation hydrolytically degrades starch chains, making them more susceptible to enzymatic degradation by α-amylase. However, the oxidized starch-based pasta systems, once esterified by Bu mainly on the amylose molecules (doubly modified pasta systems) increased their RS values, and this was more pronounced with the addition of the organocatalyst (maximum RS value = ~8%). Interestingly, despite the checked chemical changes that took place on the molecular structure of starch upon butyrylation or oxidation reactions in corn starch-based spaghetti-type pasta systems, and their incidence on starch digestibility, the orthorhombic crystalline structure (A-type starch) of starch remained unchanged.

Bio-nanocomposites films based on unmodified and modified thermoplastic starch reinforced with chemically modified nanoclays

The use of polymers capable of being degraded by the action of microorganisms and/or enzymes without causing harmful effects is a strategy in waste management and environmental care. In this work, bio-nanocomposites based on thermoplastic starch (TPS) were synthesized by reactive extrusion using a twin-screw extruder. Two strategies were evaluated to reduce the disadvantages of TPS for packaging applications. First, starch was chemically modified producing the reaction of native starch with chemical reagents that introduce new functional groups to reduce the water adsorption. And two, nano-fillers were incorporated into TPS in order to enhance the mechanical and barrier properties, driving to materials with improved performance/cost ratio. The synergistic strategies of chemical modification and incorporation of modified nanoclays were also effective to reduce the dependence of properties of TPS with the environment humidity and the evolution thereof over time, which influences the performance during the service life of the product.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10853-023-08354-1.

An Improved Optimization Model to Predict the MOR of Glulam Prepared by UF-Oxidized Starch Adhesive: A Hybrid Artificial Neural Network-Modified Genetic Algorithm Optimization Approach

The purpose of the present article is to study the bending strength of glulam prepared by plane tree (Platanus Orientalis-L) wood layers adhered by UF resin with different formaldehyde to urea molar ratios containing the modified starch adhesive with different NaOCl concentrations. Artificial neural network (ANN) as a modern tool was used to predict this response, too. The multilayer perceptron (MLP) models were used to predict the modulus of rapture (MOR) and the statistics, including the determination coefficient (R²), root mean square error (RMSE), and mean absolute percentage error (MAPE) were used to validate the prediction. Combining the ANN and the genetic algorithm by using the multiple objective and nonlinear constraint functions, the optimum point was determined based on the experimental and estimated data, respectively. The characterization analysis, performed by FTIR and XRD, was used to describe the effect of the inputs on the output. The results indicated that the statistics obtained show excellent MOR predictions by the feed-forward neural network using Levenberg-Marquardt algorithms. The comparison of the optimal output of the actual values obtained by the genetic algorithm resulting from the multi-objective function and the optimal output of the values estimated by the nonlinear constraint function indicates a minimum difference between both functions.

Chitosan-riboflavin composite film based on photodynamic inactivation technology for antibacterial food packaging

Photodynamic inactivation (PDI) is a novel sterilization technology that has proven effective in medicine. This study focused on applying PDI to food packaging, where chitosan (CS) films containing photosensitizing riboflavin (RB) were prepared via solution casting. The CS-RB composite films exhibited good ultraviolet (UV)-barrier properties, and had a visually appealing highly transparent yellow appearance. Scanning electron microscopy (SEM) confirmed even dispersion of RB throughout the CS film. The addition of RB led to improved film characteristics, including the thickness, mechanical properties, solubility, and water barrier properties. The CS-RB⁵ composite films produced sufficient singlet oxygen under blue LED irradiation for 2 h to inactivate two food-borne pathogens (Listeria monocytogenes and Vibrio parahaemolyticus) and one spoilage bacteria (Shewanella baltica). The CS-RB composite films were assessed as a salmon packaging material, where inhibition of bacterial growth was observed. The film is biodegradable, and has the potential to alleviate the issues associated with the excessive use of petrochemical materials, such as environmental pollution and limited resources. The CS-RB composite films showed potential as a novel environmentally friendly packaging material for shelf-life extension of refrigerated food products.

Reactive extrusion-processed native and phosphated starch-based food packaging films governed by the hierarchical structure

The aim of this research work was to investigate novel tools given by nanotechnology and green chemistry for improving the disadvantages typically associated to the starch-based films: water susceptibility and brittle mechanical behavior. With this in mind, four food packaging film systems were developed from corn starch or corn starch nanocrystals (SNCs), and modified by phosphating under reactive extrusion (REx) conditions using sodium tripolyphosphate (Na₅P₃O₁₀ - TPP) as a crosslinker. The structural, physicochemical, thermal, rheological and mechanical properties, as well as studies associated with the management of carbohydrate polymer-based plastic wastes (biodegradability and compostability) were carried out in this study. The hierarchical structure and the modification of the starch were dependent on the amylose content and degree of substitution (DS), which in turn depended on the hydrogen (H)-bonding interactions. In both cases, a higher molecular ordering of the starch chains in parallel was decisive to obtain the self-assembled thermoplastic starches. Beyond the valuable results obtained and scientifically analyzed, unfortunately none of the manufactured materials achieved to improve their performance compared to the control film (thermoplastic starch - TPS). It was even thought that the phosphated starch-based films could fertilize lettuce (Lactuca sativa) seedlings during their biodegradation, and this was not achieved either. This possibly due to the low content of phosphorus or its poor bioavailability.

A Comprehensive Review on Corn Starch-Based Nanomaterials: Properties, Simulations, and Applications

Corn (Zea mays L.) is one of the major food crops, and it is considered to be a very distinctive plant, since it is able to produce a large amount of the natural polymer of starch through its capacity to utilize large amounts of sunlight. Corn starch is used in a wide range of products and applications. In recent years, the use of nanotechnology for applications in the food industry has become more apparent; it has been used for protecting against biological and chemical deterioration, increasing bioavailability, and enhancing physical properties, among other functions. However, the high cost of nanotechnology can make it difficult for its application on a commercial scale. As a biodegradable natural polymer, corn starch is a great alternative for the production of nanomaterials. Therefore, the search for alternative materials to be used in nanotechnology has been studied. This review has discussed in detail the properties, simulations, and wide range of applications of corn starch-based nanomaterials.

Development and Properties of Fish Gelatin/Oxidized Starch Double Network Film Catalyzed by Thermal Treatment and Schiff' Base Reaction

In order to improve the properties of fish gelatin (FG), oxidized starch (OS) was adopted to form hetero-covalent linkage with it based on thermal treatment and the Schiff’ base reaction. The effects of different ratios of FG/OS (ranging from 10:1 to 2:1) on the properties of films were investigated. OS improved the mechanical and barrier properties of films significantly, while the moisture content decreased as OS concentration increased. The optimum concentration was obtained at the loading amount of 1.5% (w/v) OS. FT-IR spectra revealed the covalent cross-linking between FG and OS induced by Schiff’ base reaction. Moreover, composite films had superior preservation effect on blueberry, according to the results of weight loss, total soluble solids, titratable acidity, and total anthocyanin content. Therefore, this study suggested that FG-OS double network films (FODF) has great potential in the packaging industry.

Bio- and Fossil-Based Polymeric Blends and Nanocomposites for Packaging: Structure⁻Property Relationship

In the present review, the possibilities for blending of commodities and bio-based and/or biodegradable polymers for packaging purposes has been considered, limiting the analysis to this class of materials without considering blends where both components have a bio-based composition or origin. The production of blends with synthetic polymeric materials is among the strategies to modulate the main characteristics of biodegradable polymeric materials, altering disintegrability rates and decreasing the final cost of different products. Special emphasis has been given to blends functional behavior in the frame of packaging application (compostability, gas/water/light barrier properties, migration, antioxidant performance). In addition, to better analyze the presence of nanosized ingredients on the overall behavior of a nanocomposite system composed of synthetic polymers, combined with biodegradable and/or bio-based plastics, the nature and effect of the inclusion of bio-based nanofillers has been investigated.

Structural properties and in vitro digestibility of edible and pH-sensitive films made from guinea arrowroot starch and wastes from wine manufacture

A non-conventional starch obtained from guinea arrowroot tubers (Calathea allouia) grown in the Amazon was used as a polymeric matrix for the development of edible films. The films were manufactured by blending/thermo molding and plasticized with glycerol. Agro-industrial wastes from wine manufacture (grape waste flour and grape waste extract) were used as natural fillers of the thermoplastic starch (TPS) matrices. The results showed that the natural fillers caused cross-linking in the TPS matrix. This led to the production of films with higher resistant starch (RS) content, especially RS type 4 (RS4), although the DSC results showed that the films developed also contained RS type 3 (RS3). As expected, the presence of RS reduced the in vitro digestibility rate. Films made with the natural fillers were also less hydrophilic, had a greater thermal resistance, and tended towards ductile mechanical behavior. Finally, the edible film containing grape waste flour as a natural filler proved to be pH-sensitive, although this material disintegrated under alkaline conditions.