Starch Dispersions Research Articles

Effect of Concentration and Hydrocolloids Formation on Rheological Properties of Gelatinized Cassava Starch and Jackfruit Seeds Starch Dispersions

Effect of Concentration and Hydrocolloids Formation on Rheological Properties of Gelatinized Cassava Starch and Jackfruit Seeds Starch Dispersions

Starch-Based Polysaccharide Systems with Bioactive Substances: Physicochemical and Wettability Characteristics.

Polysaccharide-based systems have very good emulsifying and stabilizing properties, and starch plays a leading role. Their modifications should add new quality features to the product to such an extent that preserves the structure-forming properties of native starch. The aim of this manuscript was to examine the physicochemical characteristics of the combinations of starch with phospholipids or lysozymes and determine the effect of starch modification (surface hydrophobization or biological additives) and preparation temperature (before and after gelatinization). Changes in electrokinetic potential (zeta), effective diameter, and size distribution as a function of time were analyzed using the dynamic light scattering and microelectrophoresis techniques. The wettability of starch-coated glass plates before and after modification was checked by the advancing and receding contact angle measurements, as well as the angle hysteresis, using the settle drop method as a complement to profilometry and FTIR. It can be generalized that starch dispersions are more stable than analogous n-alkane/starch emulsions at room and physiological temperatures. On the other hand, the contact angle hysteresis values usually decrease with temperature increase, pointing to a more homogeneous surface, and the hydrophobization effect decreases vs. the thickness of the substrate. Surface hydrophobization of starch carried out using an n-alkane film does not change its bulk properties and leads to improvement of its mechanical and functional properties. The obtained specific starch-based hybrid systems, characterized in detail by switchable wettability, give the possibility to determine the energetic state of the starch surface and understand the strength and specificity of interactions with substances of different polarities in biological processes and their applicability for multidirectional use.

Formulation and Characterization of Soybean Oil-in-Water Emulsions Stabilized Using Gelatinized Starch Dispersions from Plant Sources.

Consumers are concerned about employing green processing technologies and natural ingredients in different manufacturing sectors to achieve a "clean label" standard for products and minimize the hazardous impact of chemical ingredients on human health and the environment. In this study, we investigated the effects of gelatinized starch dispersions (GSDs) prepared from six plant sources (indica and japonica rice, wheat, corn, potatoes, and sweet potatoes) on the formulation and stability of oil-in-water (O/W) emulsions. The effect of gelatinization temperature and time conditions of 85-90 °C for 20 min on the interfacial tension of the two phases was observed. Emulsification was performed using a primary homogenization condition of 10,000 rpm for 5 min, followed by high-pressure homogenization at 100 MPa for five cycles. The effects of higher oil weight fractions (15-25% w/w) and storage stability at different temperatures for four weeks were also evaluated. The interfacial tension of all starch GSDs with soybean oil decreased compared with the interfacial tension between soybean oil and water as a control. The largest interfacial tension reduction was observed for the GSD from indica rice. Microstructural analysis indicated that the GSDs stabilized the O/W emulsion by coating oil droplets. Emulsions formulated using a GSD from indica rice were stable during four weeks of storage with a volume mean diameter (d4,3) of ~1 µm, minimal viscosity change, and a negative ζ-potential.

Enhanced mechanical and long-lasting antibacterial properties of starch/PBAT blown films via designing of reactive micro-crosslinked starch

A functional starch (TPS-E) was designed and constructed by incorporating epoxy soybean oil (ESO) and an antibacterial agent polyhexamethylene guanidine hydrochloride (PHMG), then the film was prepared by reaction extrusion and blow molding using TPS-E and poly(butylene adipate-co-terephthalate) (PBAT). The micro-crosslinking structure, forming through ring-opening reaction between the epoxy active site of TPS-E and the end group of PBAT, improved the compatibility of starch/PBAT blend and reduce the dispersed starch phase size, leading to significantly increase the tensile strength. Compared to starch/PBAT films, the tensile strength of TPS-E/PBAT in the longitudinal direction increase by 112% with the same starch content of 30%. Furthermore, these TPS-E/PBAT films demonstrated long-lasting antibacterial performance with a 98% inhibition ratio even after 10 cycles, without any observed leaching of the antibacterial agent, highlighting the high coupling efficiency of PHMG. TPS-E with the degradable ESO also promotes the degradation of PBAT. Thus, an important method of synergistic improving the mechanical, degradable and antibacterial properties of blown films through the design of reactive micro-crosslinked starch structures was established.

Effects of particle properties, intermolecular forces, and molecular structure on the shear-thickening behavior of waxy starch dispersions

The shear-thickening phenomenon in waxy starch dispersions has been reported; however, the influence of starch properties on it remains unclear. Herein, the shear-thickening behavior of five waxy starch dispersions at different concentrations is investigated, and two shear-thickening areas are identified for the first time. Waxy potato and cassava starch dispersions present two shear-thickening areas, waxy maize and wheat starch dispersions exhibit one shear-thickening area, and waxy rice starch dispersion exhibits no shear-thickening behavior. Starches with high degree of polymerization (DP > 12 and > 37 chains), short-range order, relative crystallinity, melting enthalpy (ΔH), and low molecular weight easily form large particle fragments and strong intermolecular forces, thereby resulting in double shear-thickening areas. Starches with relatively high DP > 12 chains, short-range order, relative crystallinity, and ΔH form one shear-thickening area. Starches with no shear-thickening area have high molecular weight, degree of branching, and DP < 12 chains, and low short-range order, relative crystallinity, and ΔH. It can be speculated that the first shear-thickening area (2–5 s−1) is due to the presence of large particle fragments, whereas the second (10–15 s−1) is due to the interaction between the side chains of the starch molecule.

Rational design of cationic starch with high purification performance and insight into the working mechanism

The utilization of starch to treat sewage that received widespread attention has become one of the promising ways to purify water due to the advantages of low cost and biodegradability. However, the poor purification capacity for wastewater and difficult liquid phase dispersion of natural starch severely hindered its application in wastewater treatment and limited the development of starch materials. Hence, a series of cationic starches with different particle sizes were fabricated by controlling the acidification time and combining starch with N-2,3-epoxy-propyl trimethyl ammonium chloride to improve the dispersion and purification effect of starch in water. Acid hydrolysis could destroy the spatial structure of starch, which improved the etherification property to enhance the purification property of starch to different pollutants and the dispersed stable state in water. The maximum adsorption capacities of the optimal functional agents were 43.2 mg/g (methyl orange), and 236.8 mg/g (acid black) and the optimal penetration rate of the treated kaolin solution was 94.6%. The working behavior of cationic starch could be composed of rapid, stable, and equilibrium stages, and the working process of HS-g-GTA conformed to the pseudo-second-order dynamic model. This work provides a simple and low-energy pretreatment method for preparing cationic starch, which has important application value in removing anionic substances from wastewater.

Combined effect of heat moisture and ultrasound treatment on the physicochemical, thermal and structural properties of new variety of purple rice starch

The advantages of physically modifying starch are evident: minimal environmental impact, no by-products, and straightforward control. The impact of dual modification on starch properties is contingent upon modification conditions and starch type. Herein, we subjected purple rice starch (PRS) to heat-moisture treatment (HMT, 110 °C, 4 h) with varying moisture content, ultrasound treatment (UT, 50 Hz, 30 min) with different ultrasonic power, and a combination of HMT and UT. Our findings reveal that UT following HMT dispersed starch granules initially aggregated by HMT and resulted in a rougher granule surface. Rheological analysis showcased a synergistic effect of HMT and UT, enhancing the fluidity of PRS and reinforcing its resistance to deformation in paste form. The absorbance ratio R1047/1015 indicates that increased moisture content during HMT and high ultrasound power for UT reduced the short-range order degree (1.69). However, the combined HMT-UT exhibited an increased R1047/1015 (1.38–1.64) compared to HMT alone (1.29–1.45), likely due to short-chain rearrangement. Notably, the A-type structure of PRS remained unaltered, but overall crystallinity significantly decreased (23.01 %–28.56 %), consistent with DSC results. In summary, physical modifications exerted significant effects on PRS, shedding light on the mechanisms governing the transformation of structural properties during HMT-UT.

Ultrasound-assisted separation of wheat flour: Enhancing the degree of separation and characterization analysis

A novel ultrasound-assisted separation (UAS) method was proposed to enhance the efficiency of gluten starch and wheat separation. Factor experiments were conducted to optimize UAS conditions. The results showed that the highest yield of gluten and starch was obtained under probe-type ultrasonic power, temperature, and time of 500 W, 35 °C, and 15 min, respectively. Compared to non-ultrasonic separation, dry basis yield and purity of gluten increased by 0.56% and 10.96%, while A-starch yield and purity increased by 21.75% and 5.56%. Additionally, UAS improved the color and the concentration of particle size distribution for gluten and starch. UAS did not affect gluten molecular weight and disrupt starch structure, but resulted in a denser structure of gluten network and caused more starch particles to be exposed. The viscoelasticity of gluten and starch separately increased and reduced with UAS, implying ultrasound aids in the dispersion of both starch and proteins.

Effect of citric acid on the properties of thermoplastic bitter cassava starch plasticized with isosorbide

The rising concern of environmental issues from the non-degradable conventional polymers is triggering the development of sustainable and renewable polymers. Thermoplastic starch (TPS) has been known to have huge potential to substitute conventional synthetic polymers. A thermoplastic starch was prepared using a non-food bitter cassava starch with isosorbide as plasticizer. To improve the dispersion and interfacial affinity of thermoplastic starch and boost the compatibility between starch and isosorbide, citric acid (CA) was used as an additive. The influence of citric acid to the TPS was then investigated. The result shows that citric acid improved tensile strength from 8.68 MPa to 11.98 MPa. The addition of citric acid at a concentration of 1 – 10 wt % can increase glass transition temperature (Tg) from 48.81°C to 63.89°C and storage modulus at 25°C from 1.20 GPa to 3.47 GPa. Two degradation temperatures (Td) were detected which are Td1onset value was decrease from 83.32°C down to 79.78°C while Td2onset value was decrease from 275.29°C down to 247.17°C and Td2max from 311.12°C to 295.06°C.

Effect of ethanol, phytic acid and citric acid treatment on the physicochemical and heavy metal adsorption properties of corn starch

Corn starch dispersions were heated with ethanol (E) and reacted with phytic acid (E-PA), citric acid (E-CA), and a mixture of phytic and citric acid (E-PACA) under dry-heating to prepare heavy metal adsorbents. Microscopy images indicated that ethanol treatment induced the formation of porous structures on the surface; furthermore, treatment with phytic and citric acid induced indentations, pores, and irregular structures in E-PA, E-CA, and E-PACA starches. Phytic and citric acid were retained in the starch molecules through ester bonds with the phosphate and carboxyl groups, respectively. Starch esterification by phytic and citric acid induced a loss of crystallinity, high water absorption capacity, and low solubility. E-PACA starch exhibited more efficient Cu2+ adsorption (38.13 mg/g) than native, E, E-PA, and E-CA starches (0.11, 0.49, 2.05, and 36.23 mg/g, respectively). Thus, modification with ethanol, phytic acid and citric acid can be applied to prepare natural starch-based heavy metal adsorbents.

Freeze-Dried Banana Slices Carrying Probiotic Bacteria.

Findings on diet-health relationships have induced many people to adopt healthier diets, including the substitution of energy-dense snacks with healthier items, e.g., those containing probiotic microorganisms. The aim of this research was to compare two methods to produce probiotic freeze-dried banana slices-one of them consisting of impregnating slices with a suspension of probiotic Bacillus coagulans, the other based on coating the slices with a starch dispersion containing the bacteria. Both processes resulted in viable cell counts above 7 log ufc.g-1, although the presence of the starch coating prevented a significant loss in viability during freeze-drying. The coated slices were less crispy than the impregnated ones, according to the shear force test results. However, the sensory panel (with more than 100 panelists) did not perceive significant texture differences. Both methods presented good results in terms of probiotic cell viability and sensory acceptability (the coated slices being significantly more accepted than the non-probiotic control slices).

Influence of the surface/volume ratio on the rheological properties of starch dispersions

This study aims to evaluate the influence of the surface/volume granule ratio of amaranth, corn, and potato starches on the rheological properties of pastes and gels obtained at 5 and 10% solids concentration through granulometry, scanning electron microscopy, rotational, and dynamic rheological measurements. The granule size distribution and the surface/volume ratio drove the rheological behaviour as a function of temperature and concentration. At a concentration of 10%, the consistency index of corn starch (CS) paste was 147.25 Pa·sn (n – flow behavior index), a higher value compared to pastes from potato starch (PS), 86.54 Pa·sn, and amaranth starch (AS), 44.48 Pa·sn. The lowest values of the loss angle tangent (Tan δ) in CS (0.052 and 0.035) at both solids concentrations suggested a better gel conformation. Noticeable changes in consistency index and storage modulus were observed in CS. A theoretical analysis of the surface/volume ratio change showed that CS reached a 2.2 value, much lower than the 4.5 and 5.8 values for PS and AS, respectively. These findings provide additional criteria for the food industry when choosing starches with suitable rheological behaviour as a function of surface/volume granule ratio and solids concentration.

Starch oxidation and study of changing its properties for use as an adhesive component for the production of corrugated cardboard

It is known that for sizing papers and cardboards, starch is required, which has a lower viscosity compared to natural, increased stability and increased binding capacity. This is necessary so that the starch dispersions in the size press have a sufficiently high concentration, are process able and remain stable. The choice of an oxidizing agent and the conditions for the method of oxidizing corn starch are theoretically substantiated. The mechanism and regularities of the process of starch oxidation have been studied. Changes in the gel-forming and sorption properties of starch during its oxidation were revealed. The intervals of quantitative parameters of the components for the modification process are determined. The dependence of the surface tension of starch pastes on its concentration in solution has been obtained.

APPLICATION OF FIBROUS MATERIALS WITH SORPTION PROPERTIES IN WATER PURIFICATION TECHNOLOGIES

The algorithm for the technological process of obtaining a chemisorption composite material based on waste chemical fibers filled with clay powders for the purification of wastewater from heavy metal ions has been developed. Non-woven mate-rials obtained from polyurethane-polyamide chemical fiber waste were used as a basis in the work. To increase the mechanical strength, they were fastenedby the needle punching method with a knitted fabric with a surface density of 240g/m2, which was made by plaited weaving using cotton yarn with a linear density of 25 texand polyethylene complex threads with a linear density of 16.5 tex on a single-font circular knitting machine of the MS type. To strengthen the sorption capacity, clay powders of the montmorillonite type were introduced into the fibrous base in the form of filled dispersions of starch (2-3%) or polyvinyl alcohol (3%) in the amount of 5 to 10% of the mass of the dispersion.Sorption-filtering fibrous material filled with clay minerals can be used for wastewater treatment of light and chemical industry enterprises. The use of clay minerals through their introduction into the fibrous base will reduce the hydraulic re-sistance of the sorbent layer, without using a sorbent of coarse fractions, which will preserve the area of the active absorbing surface. Wastewater treatment can be carried out by passing water through a sorption-filtering element. Cleaning installations can accommodate several sorption-filtering elements at the same time, which increases the efficiency of water purification. It is possible to usechemisorption composite material for cleaning silted drains without the threat of adsorbent clogging, and in return water supply systems, which will reduce the risk of depositing mineral salts on the walls of water purification equipment and ensure high-quality operation of treatment facilities.

Effect of SBA-15-CEO on properties of potato starch film modified by low-temperature plasma

In order to improve the properties of potato starch film, cinnamon essential oil (CEO) encapsulated with mesoporous nano-silica (SBA-15) was added to the film and the potato starch dispersion was modified by low-temperature plasma (LTP). The effects of SBA-15-CEO on the physical, mechanical, antioxidant and antifungal properties of the film were investigated. Results revealed that the addition of SBA-15-CEO significantly improved the film properties. The water vapor transmission rate (WVTR) decreased from 14.01g/(m2⋅h) to 12.75g/(m2⋅h) with increasing concentrations of SBA-15-CEO. When 0.4 g/100 mL SBA-15-CEO was added, the oxygen transmittance rate (OTR) decreased from 8.113 × 10−15cm2s−1Pa−1 to 3.017 × 10−15cm2s−1Pa−1. The tensile strength (TS) and elongation at break (EB) reached maximum values when the dosage of SBA-15-CEO was 0.4 g/100 mL. The zeta potential (ZP) of the colloid solutions initially decreased and subsequently increased, corresponding to a minimum colloid solution ZP (0.947 mV) at 0.4 g/100 mL SBA-15-CEO, and a maximum (2.55 mV) at 0.8 g/100 mL SBA-15-CEO. Furthermore, the films with SBA-15-CEO exhibited antifungal and antioxidant activity. Moreover, the aggregation of SBA-15-CEO decreased with the addition of 0.4 g/100 mL, and the appearance of irregular and rough fractured surfaces were also alleviated. Fourier transform infrared (FTIR) spectroscopy revealed SBA-15-CEO to increase the hydrogen bonding of the film. This work proved the potential of LTP-PS/SBA-15-CEO (i.e., potato starch/SBA-15-CEO film modified by LTP) as an antioxidant and antifungal packaging material.

Development and properties of active films based on potato starch modified by low-temperature plasma and enriched with cinnamon essential oil coated with nanoparticles

Potato starch dispersion was modified with low-temperature plasma (LTP) and cinnamon essential oil (CEO) was successfully loaded into mesoporous nano-silica particles (SBA-15). The SBA-15-CEO/LTP-potato starch film was prepared to explore the effects of LTP and SBA-15-CEO on the thermal stability, mechanical and physical properties of the starch-based film. The results showed that the plasma modification and SBA-15-CEO improved the thermal stability and mechanical and physical properties, as well as reduced the gas permeability of the film. Significantly, the crystal structure of the LTP- potato starch film changed after adding SBA-15-CEO. The optimized SBA-15-CEO/LTP-potato starch film (1.5 g glycerin; 0.5 g SBA-15-CEO) had the best mechanical properties and thermal stability and the lowest air permeability and hydrophilicity. Moreover, the aggregation of SBA-15-CEO decreased after LTP treatment, and the appearance of irregular and rough fractured surfaces was also alleviated. After LTP modification, the agglomeration of SBA-15-CEO in the film was solved to some extent. The addition of SBA-15-CEO alleviated the problem of starch dehydration and film cracking caused by LTP modification. Therefore, LTP is a simple and environmentally friendly method to improve the properties of potato starch film.

Synthesis and characterization of biocomposites based polypropylene/thermoplastic starch- reinforced with natural STIPA TENACISSIMA fibers and PP-g-MA

The current work aims to develop environmentally friendly plastic materials by preparing a composite polypropylene/thermoplastic starch (PP/TPS) using a melt-compounding process. In order to improve the compatibility of the two naturally incompatible polymers, natural Stipa tenacissima fibers treated on their surfaces and polypropylene (PP) pellets grafted with Maleic Anhydride (MA) were added to the mixture (PP and TPS). The mixture was then prepared using the melt-mixing method in various concentrations. X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA)/Differential thermal analysis (DTA), and mechanical tensile tests were then used to characterize the various formulations. SEM images revealed that the addition of (PP-g-MA) and natural fibers resulted in good starch plasticization and higher thermoplastic starch dispersion in the polypropylene matrix. It was also discovered that increasing the TPS concentration over the PP concentration tends to reduce the mechanical tensile properties. However, the composite with 15% TPS had the best mechanical properties. The thermogravimetric analysis (TGA) results revealed that the organic filler used acted as a reinforcing agent, increasing the thermal stability of the polypropylene/thermoplastic starch (PP/TPS) compound.

Solid-state modification of tapioca starch using atmospheric nonthermal dielectric barrier discharge argon and helium plasma

Starch modification utilizes a substantial amount of water. This research aimed to investigate the effect of nonthermal dielectric barrier discharge (DBD) argon and helium plasma on tapioca starch's physicochemical properties and techno-functionality. Dry starch samples were treated with plasma generated from argon and helium gases at different voltage levels (10 and 15 kV) for 5, 10, and 15 min. The treatment did not destroy the starch’s crystalline structure, as evidenced by the birefringence under polarized light. Scanning electron micrographs showed dented starch granules. A marginal decrease in pH value of all treated samples was noted. A reduction in amylose and amylopectin molecular weight and increased reducing sugars were observed in the treated samples. Fourier transform infrared spectroscopy analysis showed a slight change in the 1047/1022 cm−1 absorbance ratio, indicating a change in short-range ordered degree of starch, while X-ray diffractometry showed a decrease in crystallinity. A significant reduction in peak viscosity, breakdown, and setback was observed. The gelatinized plasma-treated starch dispersion showed less shear-thinning and less thixotropic with increasing voltage and treatment times. This research proved that modification of starch in the solid-state using nonthermal plasma is feasible.

Effect of dual modification with citric acid combined with ultrasonication on hydrolysis kinetics, morphology and structure of corn starch dispersions

Corn starch dispersions (CSD) were hydrolyzed with citric acid and compared with CSD co-treated with citric acid combined with ultrasonication for 1 to 18 days, which are designated as single modification (CSD-SM) and dual modification (CSD-DM), respectively. The logistic functions monitor the dynamics of the hydrolysis advance (%) of the CSD-SM and CSD-DM as a function of time, where the zones most vulnerable to the single-treatment and/or co-treatment of the corn starch granules (CSG) are the amorphous or disordered regions. The characterization results of CSD-DM suggest that the structural changes caused by dual modification affected the morphology, sequence, and microstructure of the CSG. The heterogeneous changes caused by the dual modification changed the configuration of the CSG, generating a kind of destemming of the amorphous lamellae (depolymerization), an increase in the percentage of relative crystallinity of the CSD-DM and an active rearrangement of the intralamellar chains that promoted the relative amount of double helix for 18 days of double modification. The synergistic effect of the dual modification for CSD by the sequential combination of a chemical treatment followed by a physical one improved the hydrolyzed advance by 12 %, the relative crystallinity by 10 %, and the promotion of double helices by 25 % during 18 days of co-treatment.

Improvement in Thermal Stability of Flexible Poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) Bioplastic by Blending with Native Cassava Starch

High-molecular-weight poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) triblock copolymer (PLLA-PEG-PLLA) is a promising candidate for use as a biodegradable bioplastic because of its high flexibility. However, the applications of PLLA-PEG-PLLA have been limited due to its high cost and poor thermal stability compared to PLLA. In this work, native cassava starch was blended to reduce the production cost and to improve the thermal stability of PLLA-PEG-PLLA. The starch interacted with PEG middle blocks to increase the thermal stability of the PLLA-PEG-PLLA matrix and to enhance phase adhesion between the PLLA-PEG-PLLA matrix and dispersed starch particles. Tensile stress and strain at break of PLLA-PEG-PLLA films decreased and the hydrophilicity increased as the starch content increased. However, all the PLLA-PEG-PLLA/starch films remained more flexible than the pure PLLA film, representing a promising candidate in biomedical, packaging and agricultural applications.