Octenylsuccinate starch spherulites as a stabilizer for Pickering emulsions

The Preparation, Properties, and Characterization of Octenyl Succinic Anhydride-Modified Turmeric Starches and Their Emulsification for Pickering Emulsions

Turmeric has extensive applications in various fields, including food and medicine. However, research on turmeric starch remains relatively scarce. There is a significant lack of in-depth studies on its processing properties and starch modification abilities. In this context, octenyl succinic anhydride (OSA)-modified turmeric starches (O-MTSs) were synthesized. Subsequently, a comprehensive investigation was carried out, including property analysis, characterization, and evaluation of the emulsifying capacity. The alterations in solubility, swelling degree, syneresis, and transparency of turmeric starches before and after modification were systematically studied. The characterization of O-MTSs was conducted using a scanning electron microscope (SEM), particle size analysis, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis. The possibility of using O-MTS as an emulsifier to prepare Pickering emulsions was explored. The results show that O-MTS had better solubility, swelling degree, syneresis, and transparency compared to turmeric starches (TSs). The O-MTS retained a relatively intact morphology, but its particle size slightly increased, and the characteristic peak at 995 cm-1 shifted to some extent. The relative crystallinity decreased from 32.59% to 18.39%, and the water-binding capacity of O-MTSs improved accordingly. O-MTSs could better stabilize Pickering emulsions as an emulsifier compared to TSs. With the increase in the degree of substitution (DS) and concentration of the O-MTS, its emulsification index (EI) demonstrated an upward trend.

Formation and crystalline structure of spherulites from pea and high amylose maize starches

Starch spherulite is a unique form of resistant starch characterized by a spherical structure with crystalline lamellae that are radially oriented and may find applications in delivery of nutrients and bioactives to the lower gastrointestinal tract. Formation of starch spherulites generally requires heating to a high temperature followed by quenching and long crystallization time. The objectives of this study were to gain a deeper understanding of the factors influencing spherulite formation from pea starch (PS) and high-amylose maize starch (HAMS) and investigate if spherulites could be formed by a slow cooling rate and determine the crystalline structure and morphology of the spherulites formed. Remarkably, spherulite was observed immediately after PS and HAMS (25 % solids) were heated to 180 °C and cooled to 10 °C at a cooling rate of 10 °C/min in a differential scanning calorimeter (DSC) pan. Increasing heating temperature degraded starches more but improved the morphological quality of spherulites. Spherulite was better formed at 25 % solids content than 40 %. Both PS and HAMS formed spherulites with a predominant B-type crystalline pattern with 13-17 % crystallinity at ca. 10 % moisture content. PS displayed a single exothermic peak on cooling due to spherulite formation (recrystallization), whereas HAMS exhibited an extra peak due to the amylose-lipid complex formation. Spherulite production from HAMS and PS was successfully scaled up using a pressure reactor. This study provides a simplified approach for spherulite production, new potential utilization of PS and HAMS, and valuable insights for optimizing formation of starch spherulites.

The Application and Pharmaceutical Development of Etomidate: Challenges and Strategies

Etomidate is a synthetic imidazole anesthetic that exerts hypnotic effects by potentiating the action of the inhibitory neurotransmitter γ-aminobutyric acid (GABA) or directly activating the anionic GABA (GABAA) receptor. It stands out among many anesthetics because of its multiple advantages, such as good hemodynamic stability and minimal inhibition of spontaneous respiration. However, its low water solubility and side effects, such as adrenal cortex inhibition and myoclonus, have limited the clinical application of this drug. To address these issues, extensive research has been conducted on the drug delivery of etomidate in recent decades, which has led to the emergence of different etomidate preparations. Despite so many etomidate preparations, so far some of the toxic side effects have not yet been effectively addressed. Herein we discuss the pharmaceutical design of etomidate that may resolve the above problem. We also propose targeted strategies for future research on etomidate preparations and discuss the feasibility of different administration routes and dosage forms to expand the application of this drug. Through this review, we hope to draw more attention to the potential of etomidate and its application challenges and provide valuable insights into the development of new etomidate preparations.

Impact of ultra-high pressure on the microstructure, emulsification, and physicochemical properties of rice starch

Ultra-high pressure (UHP) treatment is considered a non-thermo physical treatment technology with a "clean label". Starch is an ideal stabilizer for food-grade Pickering emulsions. This study aimed to investigate the effects of ultra-high pressure (UHP) modification of rice starch on its structure, water/oil absorption, and emulsification properties under different pressure treatments (100-500 MPa), the results showed that the morphology of the starch granules and crystalline structure did not change significantly at lower pressures. Conversely, the particle size of starch increased significantly from 4.85 to 110.13 μm, the relative crystallinity (RC) obviously decreased from 18.89 % to 9.18 %, and the starch granules were destroyed and formed more fragments at higher pressure (500 MPa). The results of water/oil absorption indicated that the oil absorption slightly increased under UHP treatment, but water absorption intensively increased under higher pressure (500 MPa). The emulsifying capacity was significantly enhanced at 500 MPa after 8, 16, and 24 min. The UHP treatment induced swelling and disruption of starch granules at higher pressure (500 MPa). The starch fragments and the released starch molecules stabilized the droplets. This study provides a reference for the application of UHP processing in the starchy foods.

Physical properties and in-vitro gastrointestinal digestion of oil-in-water emulsions stabilized by single- and dual-modified cassava starches with cross-linking and octenylsuccinylation

The different modified cassava starches (MCS) obtained by either single or dual modifications with cross-linking (CL) and octenylsuccinylation (OS), including 2%CL, 3%OS, 2%CL-3%OS, and 3%OS-2%CL, were used to stabilize soybean oil-in-water emulsions (oil content 10% (w/w)) at a concentration of 4.5% (w/w) compared to native cassava starch (NCS) and their physical properties and in-vitro gastrointestinal digestion were investigated. The emulsions stabilized with NCS and 2%CL-MCS had larger oil droplet sizes, higher viscosity, and lower negative charge than the emulsions stabilized by single- or dual-MCS with 3%OS. All MCS-stabilized emulsions showed a higher emulsion stability against creaming than the NCS-stabilized emulsion. Under a simulated gastrointestinal tract, all 3%OS-MCS promoted droplet flocculation, while the less ionic NCS and the 2%CL-MCS showed a decrease in droplet size after passing through the mouth and stomach stages. The lipid digestion rate of emulsions stabilized with different MCS and NCS followed the following order: 3%OS >2%CL-3%OS > 3%OS-2%CL > 2%CL > NCS. The NCS- and 2%CL-stabilized emulsions had a lower lipid digestion rate, possibly due to the larger droplet sizes and higher viscosity of the initial emulsions, which delays access of lipase enzymes to lipid droplet surfaces, compared to all 3%OS-MCS-stabilized emulsions.

Developing biopolymer-stabilized emulsions for improved stability and bioaccessibility of lutein

Lutein is essential for infant visual and cognitive development but has low stability and solubility. This study aimed to enhance the stability and bioaccessibility of lutein using oil-in-water emulsions stabilized with biopolymers. Commercially available octenylsuccinylated (OS) starches, including capsule TA® (CTA), HI-CAP®100 (HC), and Purity Gum® 2000 (PG), along with gum Arabic (GA) variants Ticaloid acacia Max® (TAM), TICAmulsion® 3020 (TM), and pre-hydrate gum Arabic (PHGA), were chosen as emulsifiers. By screening the effect of biopolymer concentration and oil volume fraction (Φ), emulsions stabilized with CTA, HC, or TM at 20% and 30% (w/v) concentration and 70% Φ exhibited a gel-like structure and were selected for further assessments. After a week at 25 °C, emulsions stabilized by CTA and HC showed no significant change in droplet size, while TM emulsion exhibited a 1.58-fold increase. At 45 °C, all emulsions exhibited increase in droplet size. Lutein retention is higher in CTA emulsions at both storage temperatures than free lutein. In vitro bioaccessibility of all lutein emulsions was higher than that of free lutein. These findings highlight the superior stability and bioaccessibility of the lutein emulsion stabilized by OS starch, positioning it as a promising carrier to broaden lutein applications in infant foods.

Dry Ball-Milled Quinoa Starch as a Pickering Emulsifier: Preparation, Microstructures, Hydrophobic Properties and Emulsifying Properties

This research supplied a "cleaner-production" way to produce "clean-label" quinoa starch-based Pickering emulsifier with excellent emulsifying properties. The effects of dry ball-milling time and speed on the multi-scale structures and emulsifying properties of quinoa starch were studied. With increasing ball-milling time and speed, particle size first decreased and then increased, the crystallinity, lamellar structure and short-range ordered structure gradually decreased, and contact angle gradually increased. The increased contact angle might be related to the increased oil absorption properties and the decreased water content. The emulsification properties of ball-milled quinoa starch (BMQS)-based Pickering emulsions increased with the increase in ball-milling time and speed, and the emulsions of BMQS-4 h, 6 h, 8 h, and 600 r reached the full emulsification state. After 120 days' storage, the oil droplets of BMQS-2 h (BMQS-400 r) deformed, the oil droplets increased, and the emulsification index decreased. The emulsification index and the oil droplets of BMQS-4 h, 6 h, 8 h and 600 r-based emulsions did not show obvious changes after storage, indicating the good emulsifying stability of these BMQS-based emulsions, which might be because that the relatively larger amount of starch particles that dispersed in the voids among the oil droplets could act as stronger network skeletons for the emulsion gel. This Pickering emulsifier was easily and highly efficiently produced and low-cost, having great potential to be used in the food, cosmetic and pharmaceutical industries.

Mechanisms of lipid oxidation in water-in-oil emulsions and oxidomics-guided discovery of targeted protective approaches

Lipid oxidation is an inevitable event during the processing, storage, and even consumption of lipid-containing food, which may cause adverse effects on both food quality and human health. Water-in-oil (W/O) food emulsions contain a high content of lipids and small water droplets, which renders them vulnerable to lipid oxidation. The present review provides comprehensive insights into the lipid oxidation of W/O food emulsions. The key influential factors of lipid oxidation in W/O food emulsions are presented systematically. To better interpret the specific mechanisms of lipid oxidation in W/O food emulsions, a comprehensive detection method, oxidative lipidomics (oxidomics), is proposed to identify novel markers, which not only tracks the chemical molecules but also considers the changes in supramolecular properties, sensory properties, and nutritional value. The microstructure of emulsions, components from both phases, emulsifiers, pH, temperature, and light should be taken into account to identify specific oxidation markers. A correlation of these novel oxidation markers with the shelf life, the organoleptic properties, and the nutritional value of W/O food emulsions should be applied to develop targeted protective approaches for limiting lipid oxidation. Accordingly, the processing parameters, the application of antioxidants and emulsifiers, as well as packing and storage conditions can be optimized to develop W/O emulsions with improved oxidative stability. This review may help in emphasizing the future research priorities of investigating the mechanisms of lipid oxidation in W/O emulsion by oxidomics, leading to practical solutions for the food industry to prevent oxidative rancidity in W/O food emulsions.

Pickering emulsion: A multi-scale stabilization mechanism based on modified lotus root starch/xanthan gum nanoparticles

New Pickering emulsion stabilizer LS/XG-NPs (Lotus root starch/xanthan gum nanoparticles) was prepared via autoclaving-cooling method followed by combination with XG. The LS/XG-NPs showed uniform and stable particles with particle size <500 nm, PDI <30, and zeta potential 30-40. The autoclaving-cooling treatment completely changed the crystalline form (from A-type to B-type) and structure of starch; hydrogen bonding and electrostatic interactions were proved to be existed between starch and XG in LS/XG-NPs. The addition of XG increased the contact angle of LS/XG-NPs from 58.79° to 85.42°. In the prepared Pickering emulsion, the LS/XG-NPs adsorbed well on the oil droplets surface, forming a three-dimensional gel network with evenly distributed oil droplets. The Pickering emulsion prepared with LS/XG-NPs showed excellent storage stability and auto-oxidation resistance; the EPA + DHA content in the emulsion remained at 92.46 % after 5 d of storage. The results of this study suggest that LS/XG-NPs have the potential to be food-grade Pickering emulsifiers that not only stabilize emulsions but also prevent emulsion oils from oxidizing.

An "intelligent -responsive" bactericidal system based on OSA-starch Pickering emulsion

Pickering emulsion based on OSA-starch was developed in this study as an intelligent delivery system for the application of thymol against foodborne pathogens. Morphology and microstructure characterization showed that the Pickering emulsion was an O/W type emulsion and stayed stable at starch concentration of 200 mg/mL and oil fraction at 30 % with particle size of 10 μm and absolute Zeta potential of -12.5 mV. Low field nuclear magnetic resonance and rheology experiments indicated that a denser network structure was formed in this stable Pickering emulsion. Besides, the Pickering emulsion could endure long-time storage, low pH (3,5) and additional NaCl (50, 100, 200, 400 mM) and it showed enhanced bactericidal effects against Escherichia coli, Staphylococcus aureus (thymol =1.48 μmol/L) and Aspergillus flavus (thymol = 0.624 μmol/L) by inducing ROS eruption, membrane lipid peroxidation and cell shrink. Moreover, the bactericidal assay demonstrated that thymol could be intelligently released and a considerable 75 % timely bactericidal effect was detected after 9 days' intermittently exposing to E. coli, S. aureus and A. flavus in vitro, by comparison thymol alone showed only 20 % bactericidal effect due to its volatility. The results are of great importance to offer an intelligent delivery system of bio-actives defending foodborne pathogens.

Comparison of properties and application of starch nanoparticles optimized prepared from different crystalline starches

Starch nanoparticles (SNPs) were produced by nanoprecipitation combined with ultrasonication with the use of different starches (corn, potato and sago starch) and used to stabilize Pickering emulsions. The orthogonal experiment was used to optimize preparation conditions of gelatinization pretreatment duration of 30 min, ultrasonic power of 600 W, and ultrasonic time of 40 min. Compared with native starch, the SNPs were spherical in shape and displayed a V-type crystalline structure with low relative crystallinity and higher degree of double-helix. Compared with native starch-Pickering emulsion, the SNP-Pickering emulsion had a smaller droplet size, more uniform distribution, clearer oil/water interface, and higher static stability of droplets. The sago SNP-Pickering emulsion had the great gelatinous structure and emulsion stability. In addition, the SNP-Pickering emulsion had the better loading efficiency and controlled release performance of curcumin. Meanwhile, the bioavailability of curcumin in sago SNP-Pickering emulsion was highest.

Effect of shell separation pretreatment on the physicochemical properties of octenyl succinic anhydride-modified starch

The effects of shell separation pretreatment (SSP) on the physicochemical properties of octenyl succinic anhydride (OSA)-modified starch were investigated in this study. SSP at different temperatures promoted esterification between starch molecules and OSA and thereby achieved a higher degree of substitution (DS). OSA-modified granule shells (OSC_s) exhibited a rough surface and irregular shape, which were attributed to swelling caused by SSP during modification processes. The paste viscosity and viscoelastic properties of OSC_s were enhanced after SSP. Both the swelling power and transparency of OSA esterified starch increased with DS values after SSP. The content of resistant starch (RS) among OSA esterified starch increased from 33.18 % to 45.33 %, which mainly occurred when SSP was introduced into the OS starch synthesis process. In summary, SSP at different temperatures promoted the unique physicochemical properties of OSC_s specimens by increasing their DS values.

Mesona chinensis polysaccharide accelerates the short-term retrogradation of debranched waxy corn starch

The effect of non-starch polysaccharides on the structural and functional properties of native starch have been extensively studied. However, the effect of non-starch polysaccharides on the structural characteristics of debranched starch, a kind of enzymatic modified starch, remains unclear. The aim of this study is to investigate the effects of Mesona chinensis polysaccharide (MP) on starch retrogradation and structural properties of debranched waxy corn starch (DWS). The results showed that only appropriate addition of MP (0.5 or 1%) can effectively promote the short-term retrogradation of DWS, while excessive MP (3 or 5%) had a negative effect. Gel hardness results revealed that the short-term retrogradation (24 h) of DWS could be divided into two phases. The retrogradation of DWS-MP gels mainly occurred at first stage (0–4 h), which was demonstrated by the rapid increase of gel hardness and relative crystallinity in this stage. In the second stage (4–24 h), DWS-MP gels were more likely to undergo the aggregation of starch granules as proved by SEM and particle size results. The degree of short-range ordered decreased during the total retrogradation stage. Overall, this work aims to provide an insight into the effect of non-starch polysaccharides on the short-term retrogradation of DWS.

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Only the appropriate addition of MP could accelerate the retrogradation of DWS.

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The short-term retrogradation of DWS could be divided into two stages.

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Gel hardness and relative crystallinity increased significantly in the first stage.

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The degree of short-range ordered reduced monotonically with retrogradation time.

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Starch particles mainly underwent aggregation in the second stage.

Recent progress in Pickering emulsions stabilised by bioderived particles

In recent years, the demand for non-surfactant based Pickering emulsions in many industrial applications has grown significantly because of the option to select biodegradable and sustainable materials with low toxicity as emulsion stabilisers. Usually, emulsions are a dispersion system, where synthetic surfactants or macromolecules stabilise two immiscible phases (typically water and oil phases) to prevent coalescence. However, synthetic surfactants are not always a suitable choice in some applications, especially in pharmaceuticals, food and cosmetics, due to toxicity and lack of compatibility and biodegradability. Therefore, this review reports recent literature (2018-2021) on the use of comparatively safer biodegradable polysaccharide particles, proteins, lipids and combinations of these species in various Pickering emulsion formulations. Also, an overview of the various tuneable factors associated with the functionalisation or surface modification of these solid particles, that govern the stability of the Pickering emulsions is provided.

Recent Developments in the Formulation and Use of Polymers and Particles of Plant-based Origin for Emulsion Stabilizations

The main scope of this Review was the recent progress in the use of plant-based polymers and particles for the stabilization of Pickering and non-Pickering emulsion systems. Due to their availability and promising performance, it was discussed how the source, modification, and formulation of cellulose, starch, protein, and lignin-based polymers and particles would impact their emulsion stabilization. Special attention was given toward the material synthesis in two forms of polymeric surfactants and particles and the corresponding formulated emulsions. Also, the effects of particle size, degree of aggregation, wettability, degree of substitution, and electrical charge in stabilizing oil/water systems and micro- and macro-structures of oil droplets were discussed. The wide range of applications using such plant-based stabilizers in different technologies as well as their challenge and future perspectives were described.

Pickering emulsifiers based on enzymatically modified quinoa starches: Preparation, microstructures, hydrophilic property and emulsifying property

Quinoa starch was developed as a new kind of Pickering emulsifier by enzymatic modification. The morphological structure, crystalline structure, lamellar structure, fractal structure, particle size distribution, contact angle, emulsion index (EI), and emulsion micromorphology were studied to explore the relationship between structure characteristics, hydrophilic property, and emulsifying properties of enzymatically modified (EM) quinoa starches. With the increasing enzymatic hydrolysis time in the test range of 0-9 h, particle size of EM quinoa starch decreased, and the broken starch and contact angle of EM quinoa starch increased; the EI value of emulsions with EM quinoa starch increased, and the oil droplet size of emulsions with EM quinoa starch decreased. It suggested that both the smallest particle size and the closest extent of the contact angle to 90° derived the best emulsifying property of EM-9. The EM quinoa starch had higher emulsifying capacity at higher oil volume fraction (Φ) (50%) than at lower Φ (20%), proving that the EM starch has potential to be used as Pickering emulsifiers in higher oil products, such as salad dressing.

Atmospheric pressure plasma jet pretreatment to facilitate cassava starch modification with octenyl succinic anhydride

Cassava starch (CS) was pretreated with atmospheric pressure plasma jet (APPJ), followed by esterification with octenyl succinic anhydride (OSA). This study was the first report investigating the effect of APPJ on CS modification with OSA. Results showed that APPJ pretreatment could change the morphological characteristics and crystallinity of CS. Consequently, the degree of substitution and reaction efficiency significantly improved compared with the unpretreated CS (P < 0.05). In Confocal laser scanning microscopy, the fluorescence intensity of OSA-modified CS pretreated with APPJ for 10 min and 15 min was higher than those pretreated with APPJ for 1, 3, and 5 min. The onset temperature and enthalpy (ΔH) of native starch decreased after APPJ pretreatment and further decreased by OSA modification. APPJ-OSA-CS also showed better emulsion stability and emulsion activity. This study demonstrated that APPJ could be used as a novel approach to facilitate starch modification with OSA.

Pickering emulsions stabilized by some inorganic materials

The paper presents studies of various solid stabilizers of emulsions based on inorganic materials. Inorganic colloidal particles have an advantage for obtaining of stable emulsions due to their safety for use in food, cosmetics, pharmaceutical industry and medicine. Pickering emulsions have a higher biodegradability compared to classical emulsions stabilized with surfactants. An overview of inorganic substances such as silicon dioxide, clay materials, metal and metal oxide nanoparticles, calcium compounds and carbon particles used for stabilizing of Pickering emulsions is considered. A variety of solid inorganic particles as well as modification of their surfaces by surfactants allows to obtain the stable Pickering emulsions of different types for a wide range of applications. It should be noted that despite a large number of studies, this class of disperse systems is still not studied fully; various methods of their preparation and influence of solid particle size on stability and size of emulsions droplets are shown.

Effect of drying treatment on the structural characterizations and physicochemical properties of starch from canistel (Lucuma nervosa A.DC)

This work investigated the effects of hot air drying pretreatment (HAD), freeze drying pretreatment (FD) and vacuum drying pretreatment (VD) on the physicochemical properties and structural characterizations of starch isolated from canistels. X-ray diffraction displayed that the starches separated from canistel by different drying pretreatments showed a typical A-type crystal structure. The SEM image showed that cracks and debris appeared on the surface of HVD and VD particles. The molecular structure of starches obtained by different drying pretreatments was studied using Fourier infrared and solid state ¹³C CP/MAS NMR analysis. The results indicated that vacuum drying pretreatment could promote the formation of the double helix of starch granules, and hot air drying and freeze drying destroyed the ordered structure of starch granules. These structural changed to affect the physicochemical properties of starch granules. The study of different drying pretreatments to separate starches provided practical value for drying pretreatments. Furthermore, the current study affords information for canistel starches cultivated in China that would be convenient for commercial applications.

Novel gel-like Pickering emulsions stabilized solely by hydrophobic starch nanocrystals

The development of gel-like Pickering emulsions stabilized by edible particles has attracted significant interest in the food colloid field. This work reported that starch nanocrystals (SNCs), modified by octenyl succinic anhydride (OSA), could introduced as a natural stabilizer for gel-like Pickering emulsions. The formation, microstructure and stability of Pickering emulsions were characterized by visual observations and optical microscopy. The results indicated that surface modification improved the hydrophobicity and aqueous re-dispersibility of SNCs, as well as the emulsification performance of them. The stable gel-like Pickering emulsions were formed at different oil volume fractions (range from 40% to 74%), increasing the degree of substitution (DS: from 0.010 to 0.018) led to gel-like emulsion stronger stiffness. These findings offer a promising opportunity to develop a kind of novel edible gel-like Pickering emulsions stabilized by OS-SNCs for the food and pharmaceutical industries.

Starch granule stabilized Pickering emulsions: an 8-year stability study

BACKGROUND

Pickering emulsions are known to have advantages over conventional emulsions, in particular, improved and long-term stability against coalescence. This research is an eight-year stability investigation of oil-in-water Pickering emulsions stabilized by quinoa starch granules modified by octenyl succinic anhydride (OSA). Two different concentrations of starch (i.e. 200 and 600 mg mL^-1 based on oil) were used at oil fraction (ϕ) of 0.1. The emulsions were prepared using a high-pressure homogenizer. The emulsions were stored in a refrigerator (at 6 °C) and evaluated using particle size analyzer over the storage period and light microscopy at the end of the storage period.

RESULTS

Starch granule stabilized Pickering emulsions produced by a high-pressure homogenizer displayed remarkable storage stability over the eight years with no indication of coalescence. In addition, the results showed that increasing the concentration of starch granules resulted in a decrease in droplet sizes. The sizes measured by the particle size analyzer showed a decline over the storage period which was due to dissociation of some networks of aggregated droplets that, in addition to representing smaller droplet sizes, resulted in the release of free and unbound starch entrapped in these networks.

CONCLUSIONS

This study showed that Pickering emulsions produced by OSA modified starch granules from quinoa can be used in practical applications for the development of highly stable formulations when prolonged storage is required. © 2020 Society of Chemical Industry.

Joint Effects of Granule Size and Degree of Substitution on Octenylsuccinated Sweet Potato Starch Granules As Pickering Emulsion Stabilizers

The granules of sweet potato starch were size fractionated into three portions with significantly different median diameters ( D₅₀) of 6.67 (small-sized), 11.54 (medium-sized), and 16.96 μm (large-sized), respectively. Each portion was hydrophobized at the mass-based degrees of substitution (DS_m) of approximately 0.0095 (low), 0.0160 (medium), and 0.0230 (high). The Pickering emulsion-stabilizing capacities of modified granules were tested, and the resultant emulsions were characterized. The joint effects of granule size and DS_m on emulsifying capacity (EC) were investigated by response surface methodology. For small-, medium-, and large-sized fractions, their highest emulsifying capacities are comparable but, respectively, encountered at high (0.0225), medium (0.0158), and low (0.0095) DS_m levels. The emulsion droplet size increased with granule size, and the number of freely scattered granules in emulsions decreased with DS_m. In addition, the term of surface density of the octenyl succinic group (SD_-OSG) was first proposed for modified starch granules, and it was proved better than DS_m in interpreting the emulsifying capacities of starch granules with varying sizes. The present results implied that, as the particulate stabilizers, the optimal DS_m of modified starch granules is size specific.

Fabrication of mesoporous POMs/SiO2nanofibers through electrospinning for oxidative conversion of biomass by H2O2and oxygen

The oxidation process for mesoporous H₅PMo₁₀V₂O₄₀/SiO₂nanofiber catalyst.