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Waxy rice starch (St) was modified by pre-OSA esterification reaction followed by ozone treatment. The molecular structure of this modified product (OSA-OSt) was characterized, and the thermal behaviors and its stabilized Pickering emulsion were evaluated. 1HNMR and XPS results discovered that ozone initially oxidized the hydroxyl groups in the amorphous region of starch (preferentially C2/C3) along with a degree of crosslinking, enhancing the molecular orderliness. This led to an increase in water-holding capability (29.15%) and swelling power (52.8 g/g), and a decrease in solubility (0.35%). TGA, RVA, and DSC indicated that oxidation-induced crosslinking within a brief treatment period enhanced the starch's thermal stability. The structural change enabled the formation of a weak gel structure during the heating process, which displayed high thermal and freeze-thaw stability. The work proves ozone is an effective way of improving the thermal behavior of OSA-starch and its emulsion for subsequent applications in numerous food products.

• Encapsulation rate of curcumin in emulsions decreased with increasing oil fraction. • The highest encapsulation efficiency of curcumin in emulsion gels reached 96.0%. • The highest bioavailability of curcumin in emulsion gels was 67.3%. • Emulsion gels exhibited high protective effect on curcumin against light irradiation. The objective of this study was to enhance the bioavailability and stability of curcumin (Cur) by encapsulating it in corn starch (CS)/octenylsuccinic acid modified (OSA)-starch-whey protein isolate (WPI) emulsion gels (EGs). As the volume fraction of the oil phase increased, the droplet size and ζ- potential of the EGs decreased. The encapsulation efficiency and bioavailability of Cur in CS/OSA-starch-WPI EGs with a 60% oil ratio were 96.0% and 67.3%, respectively. The release rate of free fatty acid and the bioavailability of Cur from the EGs after digestion were significantly higher compared to Cur dissolved in oil. EGs with an oil phase volume fraction of 75% and 80% demonstrated greater protection against light irradiation but were less effective against UV irradiation compared to EGs with a 60% oil phase volume fraction. Encapsulation in EGs proved to be an effective method for enhancing the bioavailability and stability of Cur. [ABSTRACT FROM AUTHOR]

Waxy rice starch (St) was modified by pre-OSA esterification reaction followed by ozone treatment. The molecular structure of this modified product (OSA-OSt) was characterized, and the thermal behaviors and its stabilized Pickering emulsion were evaluated. 1 HNMR and XPS results discovered that ozone initially oxidized the hydroxyl groups in the amorphous region of starch (preferentially C2/C3) along with a degree of crosslinking, enhancing the molecular orderliness. This led to an increase in water-holding capability (29.15%) and swelling power (52.8 g/g), and a decrease in solubility (0.35%). TGA, RVA, and DSC indicated that oxidation-induced crosslinking within a brief treatment period enhanced the starch's thermal stability. The structural change enabled the formation of a weak gel structure during the heating process, which displayed high thermal and freeze-thaw stability. The work proves ozone is an effective way of improving the thermal behavior of OSA-starch and its emulsion for subsequent applications in numerous food products., Competing Interests: We declare that no conflict of interest exists in the submission of this manuscript entitled “Ozone induced structural variation in OSA waxy rice starch: Effects on the thermal behavior of starch and its stabilized Pickering emulsion”, and the manuscript is approved by all authors including Meng Du 1, 2, Lei Chen 1, 2*, Zia-ud Din 3, Xinya Liu 2, Xi Chen 1, 2, Yuehui Wang 1, Kun Zhuang 1, 2, Lijie Zhu 1, 2, Wenping Ding 1, 2⁎. I want to declare on behalf of my co-authors that the work described is original research that has not been published previously and is not under consideration for publication elsewhere, in whole or in part. All the authors listed have approved the manuscript that is enclosed., (© 2024 The Authors. Published by Elsevier Ltd.)

Applications for vanilla essential oil extracted from vanilla pods have been limited since the effective components of vanilla could be easily influenced by environmental factors, such as temperature, light, and oxygen, which hinder their effectiveness. In this study, vanilla essential oil was encapsulated in a Pickering emulsion with octenyl succinic acid starch (OSA—starch). The optimal process conditions for emulsion preparation were determined as 5% vanilla essential oil phase with 2.5% OSA—starch when they were ultrusonicated for 3 min at 470 W. Under these conditions, the minimum particle size was 0.456 μm, the oil droplets were completely encased by starch, and no new chemical bonds were formed. The smallest particle size was produced at a pH of 4 and 500 mM ion concentration. The antioxidant activity of the emulsion was greater than that of the pure vanilla oil at the same oil content. After 24 h storage, the antioxidant activity of the emulsion was enhanced, and the vanilla essential oil was slowly released in the emulsion. These results indicated that the vanilla essential oil encapsulated in a Pickering emulsion with octenyl succinic acid starch showed its tremendous potential for use in the food industry. [ABSTRACT FROM AUTHOR]

Applications for vanilla essential oil extracted from vanilla pods have been limited since the effective components of vanilla could be easily influenced by environmental factors, such as temperature, light, and oxygen, which hinder their effectiveness. In this study, vanilla essential oil was encapsulated in a Pickering emulsion with octenyl succinic acid starch (OSA—starch). The optimal process conditions for emulsion preparation were determined as 5% vanilla essential oil phase with 2.5% OSA—starch when they were ultrusonicated for 3 min at 470 W. Under these conditions, the minimum particle size was 0.456 μm, the oil droplets were completely encased by starch, and no new chemical bonds were formed. The smallest particle size was produced at a pH of 4 and 500 mM ion concentration. The antioxidant activity of the emulsion was greater than that of the pure vanilla oil at the same oil content. After 24 h storage, the antioxidant activity of the emulsion was enhanced, and the vanilla essential oil was slowly released in the emulsion. These results indicated that the vanilla essential oil encapsulated in a Pickering emulsion with octenyl succinic acid starch showed its tremendous potential for use in the food industry.

In the present work, a dual-modified waxy rice starch (OOWRS) fabricated with OSA and ozone was successfully used to stabilize the O/W Pickering emulsion. The molecular structure, surface properties, and underlying stabilizing mechanism were systematically investigated. The results showed that oxidation occurring on the surface of OSA-modified waxy rice starch (OSAWRS) resulted in the presence of indentations and cracks. The relative crystallinity of starch was generally decreased with increasing degree of oxidation. Due to the introduction of carbonyl and the variation in surface structure, the hydrophobicity and acidity of OSAWRS were significantly enhanced after the ozone treatment. Remarkably, OOWRS stabilized Pickering emulsion exhibited a feature of typical O/W emulsion, and the 0.5 h and 1 h OOWRS emulsion exhibited a more uniform droplet size as well as a higher surface potential. We also noted that a weak-gel network was formed within the OOWRS emulsion system as the hydrophilic starch chains played a bridging role. Two reasons for the improved stability of the emulsion were the special gel structure and the enhanced electrical repulsion among the droplets. This research provides that ozone-conjugated OSA modification is a promising strategy for improving the emulsion ability of starch-based Pickering emulsions. [Display omitted] [ABSTRACT FROM AUTHOR]

Cereals are subject to contamination by pathogenic fungi, which damage grains and threaten public health with their mycotoxins. Fusarium graminearum and its mycotoxins, trichothecenes B (TCTBs), are especially targeted in this study. Recently, the increased public and political awareness concerning environmental issues tends to limit the use of traditional fungicides against these pathogens in favor of eco-friendlier alternatives. This study focuses on the development of biofungicides based on the encapsulation of a curcumin derivative, tetrahydrocurcumin (THC), in polysaccharide matrices. Starch octenylsuccinate (OSA-starch) and chitosan have been chosen since they are generally recognized as safe. THC has been successfully trapped into particles obtained through a spray-drying or freeze-drying processes. The particles present different properties, as revealed by visual observations and scanning electron microscopy. They are also different in terms of the amount and the release of encapsulated THC. Although freeze-dried OSA-starch has better trapped THC, it seems less able to protect the phenolic compound than spray-dried particles. Chitosan particles, both spray-dried and lyophilized, have shown promising antifungal properties. The IC50 of THC-loaded spray-dried chitosan particles is as low as 0.6 ± 0.3 g/L. These particles have also significantly decreased the accumulation of TCTBs by 39%.

Highlights • The idea of chemical surface gelatinization was applied in starch succinylation. • Pre-treatment with 1.0 M CaCl 2 increased reaction efficiency of succinylation. • OSA-1.0 M-starch showed improved functional properties over OSA-starch. Abstract Potato starch was pre-treated with CaCl 2 solutions prior to modification with octenyl succinic anhydride (OSA). Starch pre-treated with 1.0 M CaCl 2 showed higher degree of substitution (DS) and reaction efficiency (RE) on OSA modification, whereas pre-treatment with CaCl 2 solutions at 0.05 M, 0.1 M and 0.5 M had no effect on DS and RE. CaCl 2 pre-treatment decreased the swelling power, paste clarity, peak viscosity (PV), breakdown (BD) and some textural parameters of potato starch, with the effects being greater at higher concentrations of CaCl 2. Pre-treatment with 1.0 M CaCl 2 caused a small disruption to starch crystallinity and granule morphology. OSA modification significantly decreased the textural parameters, PV, BD, relative crystallinity, swelling power, gelatinization temperatures and enthalpy of potato starch, but it increased the paste clarity and emulsifying activity. OSA-1.0 M-starch showed improved functional properties over OSA-starch, indicating that CaCl 2 pre-treatment provides advantages for improving the functional characters of succinylated starch. [ABSTRACT FROM AUTHOR]

Octenyl succinic anhydride starch (OSA-starch) is often used as an emulsifier to protect bioactive compounds such as essential oils. In this study, rosemary essential oil was encapsulated in OSA-starch capsules via electrospraying an emulsion. Creaming was observed in the emulsions with 40% ethanol (v/v) 2 h after preparation, and phase separation occurred after 4 days. The emulsion with 20% ethanol revealed smaller droplets and lower zeta potential, and remained stable for 7 days. The morphology, loading capacity (LC), and encapsulation efficiency (EE) of the capsules, electrosprayed from the emulsions, were evaluated. The capsules from 20 and 30% aqueous ethanol (v/v) were smooth and spherical in shape with few dimpled. EE values were higher in the emulsions with 20% ethanol (82%–98%) when compared to those with 30% ethanol (89%–96%), except when 30% oil content was used. Fourier-transform infrared spectrometry suggested interaction of essential oil with the wall material. In summary, OSA-starch produced a stable emulsion that was suitable for electrospraying into capsules. [ABSTRACT FROM AUTHOR]

Octenyl succinic anhydride (OSA)-modified waxy starches are used widely as emulsifiers and stabilizers in the food and beverage industry. Selection of appropriate OSA-starch and oil phase is important to ensure that emulsion-based products exhibit desired properties and are stable. Here, we studied the structural characterization, and interfacial properties of three OSA-starches with different multi-scale molecular structures (OSA-W1, OSA-W2, and OSA-W3) and their emulsifying stabilities when combined with various different food-grade oil phases (medium-chain triglyceride (MCT), corn oil, and palm oil). Interfacial tension decreased as the degree of substitution ( DS ) of OSA-starches increased. Compared with OSA-W1, OSA-W2 exhibited a greater hydrodynamic radius ( R h ). The OSA-W2 based emulsion, possessing the largest droplets, was sensitive to droplet size increase (from 255 to 299 nm) due to crosslink between droplets, but stable to gravity separation (ΔT, the difference in transmission between the bottom and middle layers, was only 0.2% after 30 days). OSA-W3, with the highest DS (3.83%) and smallest R h , formed fine stable emulsion droplets that did not increase substantially in diameter during storage (180 nm initially, 190 nm after 30 days), but exhibited poor gravitational stability (ΔT = 26.2% after 30 days). Of the three oils tested, the MCT oil-in-water emulsion had the greatest stability and maximum oil loading; appropriate absorbance of starch on the surface created a strong interface. Thus, we provide valuable information guiding the selection of appropriate OSA-starch and oil phase for use in the food and beverage industry. [ABSTRACT FROM AUTHOR]

Octenyl succinic anhydride modified starches (OSA-starches) are widely used as emulsifiers and stabilizers in the food industry. Selection of optimal OSA-starches for a given application would be facilitated with better understanding of the relations between performance and molecular structure, and the mechanistic reasons for observed correlations. Structural parameters, including molecular size distribution, chain-length distribution, degree of branching, degree of substitution (DS) and amount of small molecules such as maltose, were characterized using size-exclusion chromatography (SEC, also termed GPC) and 1 H nuclear magnetic resonance (NMR), and were correlated with the functional properties of viscosity, emulsion droplet size and emulsion stability. The observed correlations varied with the methods used to make the OSA-starch, which affects gross structural features. The viscosity of OSA-starch solutions was related to starch molecular size and the relative amounts of small molecules; the DS showed positive correlation with viscosity. Emulsion droplet size is mainly determined by the whole molecular size of the OSA-starch. Emulsion stabilization efficacy is mainly affected by the average chain length. These correlations can be rationalized by basic precepts of the behaviour of polymer chains in solution and the fundamentals of electrosteric stabilization. [ABSTRACT FROM AUTHOR]

Pre-treatments by freezing/thawing (F/T) and hydrothermal-alkali (HA) were used in the modification of starch with octenyl succinic anhydride (OSA). In comparison with OSA-modified starch prepared without pre-treatment (degree of substitution, DS = 0.0172; reaction efficiency, RE = 73.9%), HA pre-treatment increased the DS of OSA-starch and RE of subsequent OSA modification (0.0185 and 79.7%, respectively). In contrast, F/T pre-treatment gave the opposite results (0.0152 and 65.5%, respectively). OSA modification markedly increased the viscosities but decreased the gelatinization parameters of native starch. Esterification of starch by OSA was confirmed with Fourier transform infrared and Raman spectroscopy, which indicated markedly decreased short-range molecular orders of native starch. The present study showed that HA pre-treatment before OSA modification is an efficient way to improve the reaction efficiency of OSA with starch and thereby to modify the pasting properties of starch. F/T pre-treatment did not increase the reaction efficiency of starch with OSA. [ABSTRACT FROM AUTHOR]

The objectives of this study were to examine the influence interfacial composition on environmental stresses stability of oil in water emulsions. An electrostatic layer-by-layer deposition method was used to create the multilayered interfacial membranes with different compositions: (i) primary emulsion (Soy protein Isolate); (ii) secondary emulsion (Soy protein Isolate – OSA-starch); (iii) tertiary emulsion (Soy protein isolate – OSA-starch – chitosan). Fourier transform-infrared (FTIR) and scanning electron microscopy (SEM) results confirmed the adsorption of charged polyelectrolyte onto oppositely charge polyelectrolyte-coated oil droplets. The stability of primary, secondary, and tertiary emulsions to thermal treatment (30 min at 30–90°C), pH (3–7) and NaCl (0–500 mM) were determined using ζ-potential, particle diameter, and microstructure analysis. Primary emulsions were unstable at pH 4–7, salt concentrations, and thermal treatments. Secondary emulsions were stable to creaming and droplet aggregation at pH 3–5, at ≤50 mM NaCl, and unstable at thermal treatments, whereas tertiary emulsions were stable at all salt concentrations, thermal treatments, and at pH 3–6. These results demonstrate that these polymers can be used to engineer oil in water emulsion systems and improve the emulsion stability to environmental stresses. [ABSTRACT FROM PUBLISHER]

The objective of this work was to microencapsulate vanillin by multilayer emulsion followed by spray drying, aiming to protect it and control its release. An electrostatic layer-by-layer deposition method was used to create the multilayered interfacial membranes around microcapsules with different compositions: (i) one-layer (soy protein isolate); (ii) two-layer (soy protein isolate – OSA starch); (iii) three-layer (soy protein isolate – OSA starch – Chitosan). The morphology of the microcapsules was analyzed by scanning electronic microscopy. The hygroscopicity, solubility, particle size, encapsulation efficiency, Fourier transform infrared spectroscopy and release into water (37 °C and 80 °C) were also examined. FTIR confirmed the interaction between the wall materials. All microcapsules were not very water-soluble or hygroscopic while three-layer microcapsules compared to one and two layer microcapsules have lower moisture content and predominantly shriveled surfaces. The results indicated it was possible to encapsulate vanillin with the techniques employed and that these protected the vanillin even at 80 °C. The reduced solubility and low release rates indicated the enormous potential of the vehicle developed in controlling the release of the vanillin into the food and pharmaceuticals. [ABSTRACT FROM AUTHOR]

Quercetin is a strong antioxidant flavonoid with several bioactive properties such as anti-inflammatory and anticarcinogenic activities, becoming an interesting compound to be incorporated into pharmaceutical, cosmetic or food products. However, these applications are limited by the low bioavailability of this flavonoid. Quercetin is poorly soluble in aqueous media, such as gastrointestinal fluids, being also degraded by gut flora. Thus, it is necessary the development of quercetin's formulations capable of improving its water solubility resulting in increased bioavailability and thus higher biological activity of this compound. The aim of the present work was the formulation of quercetin using three distinct natural origin surfactants, namely OSA-starch, Lecithin and β-glucan, by precipitation from a pressurized ethyl acetate-in-water emulsion. Formulations of quercetin with encapsulation efficiencies up to near 76% and a micellar particle size in the range of nanometers were obtained using lecithin. An improved antioxidant activity (3-fold higher per unit mass of quercetin) was also observed in these formulations, demonstrating that lecithin is a good emulsifier for the encapsulation of quercetin. Furthermore, the addition of glycerol as co-solvent increased the colloidal stability of the suspension and the encapsulation efficiency of the flavonoid. [ABSTRACT FROM AUTHOR]

Starch nanospheres smaller than 200 nm were produced from hydrophobically modified starch by using initial water dialysis method. The hydrophobic modification of starch was performed by using octenyl succinic anhydride (OSA). The resultant starch nanospheres were characterized by using Fourier transformation infrared (FTIR) spectroscopy, 1 H nuclear magnetic resonance ( 1 H NMR) spectroscopy and fluorescence spectroscopy, scanning electron microscopy (SEM) and dynamic light scattering (DLS). Effects of degree of substitution (DS) in OSA-starch, initial water content and OSA-starch concentration on morphology and particle size of starch nanospheres were evaluated. The SEM micrographs showed that starch nanospheres with spherical shape and sharp edge can be produced at DS values ≧0.67. The particle size of starch nanospheres decreased significantly ( P < 0.05) with increase in DS of OSA-starch and increase in the initial water content, whereas the particle size increased significantly ( P < 0.05) with the increase in the concentration of OSA-starch. These OSA-starch nanospheres can be preferentially used to microencapsulate hydrophobic drugs. [ABSTRACT FROM AUTHOR]

Octenyl-succinic anhydride (OSA)-modified starch was used as an emulsifier in oil-in-water emulsions. Multiple analytical techniques, including size-exclusion chromatography (SEC), confocal laser scanning microscopy (CLSM), and laser diffraction particle size analysis were used to determine the structure and emulsification properties of OSA-starch. The results indicated that OSA-starch with a smaller molar mass exhibited improved emulsification properties than its larger counterparts. Furthermore, samples pretreated by enzymatic modification for 25 min showed the best droplet size distribution, improved emulsion stability, and minimum aggregation. It was also determined that stable emulsions were not formed when the average molar mass of OSA-starch was too small. The emulsion ability of OSA-starch enzymatically modified for 35 min was found to be a little inferior than that of OSA-starch upon enzyme treatment for 25 min. [ABSTRACT FROM AUTHOR]

Abstract: β-carotene is one of the most common pigments in nature. The application of β-carotene as natural colorant in food and nutraceutical products requires an appropriate formulation in order to protect the active compound from degradation and overcome the low bioavailability due to a low solubility in aqueous media. This work presents a study of the formulation of β-carotene using four different modified n-octenyl succinate (OSA) starches as carrier materials by precipitation from a pressurized ethyl acetate-in-water emulsion. The best results, with encapsulation efficiencies of 70–80% and particle sizes in the sub-micrometer range, were achieved using a OSA-starch refined from waxy maize at concentrations of at least 100 g L−1. Moreover, experiments using ethanol instead of ethyl acetate as organic solvent have been carried out in order to assess the influence of the emulsification, solvent displacement and antisolvent precipitation processes on product characteristics. Equivalent particle sizes were obtained in experiments with ethanol, but with encapsulation efficiencies below 40%, indicating that the formation of an emulsion template is essential in order to achieve a high encapsulation efficiency, while particle sizes are determined by antisolvent precipitation processes. [Copyright &y& Elsevier]

Highlights: [•] The production of water-soluble β-carotene formulations was studied. [•] Three techniques were compared: high shear, ultrasound and pressurized emulsion. [•] High shear and ultrasound emulsification yielded similar particle sizes near 200nm. [•] Encapsulation efficiency by high shear was lower than by ultrasound emulsification. [•] Pressurized emulsions yielded higher efficiencies but also higher particle sizes. [ABSTRACT FROM AUTHOR]

• Stable W/O HIPEs were prepared firstly by polysaccharide mixtures and PGPR. • The novel W/O HIPEs showed a satisfactory pH, ionic strength, and heating stability. • Polysaccharide mixtures could reduce the oil–water interface tension of HIPEs. • The EGCG storage stability and bioaccessibility were improved by HIPEs encapsulation. Water-in-oil (W/O) high internal phase emulsions (HIPEs) were prepared using polyglycerol polyricinoleate (PGPR) and polysaccharide blends consisting of konjac glucomannan (KGM) and octenyl succinic anhydride starch (OSA-starch). The formation, stability, and functionality of these emulsions were varied by adjusting the ratio of KGM and OSA-starch. Interfacial tension measurements indicated that the OSA-starch co-adsorbed to the water–oil interface with PGPR, which would have led to the formation of a polysaccharide-layer that helped prevent separation of the HIPEs. The centrifugal stability, rheological and microstructural results indicated that the W/O HIPEs exhibited well pH, ionic and thermal stability. The encapsulation efficiency, stability, and bioaccessibility of the EGCG in the W/O HIPEs were evaluated by using EGCG as a model hydrophilic nutraceutical. This study provides useful insights into the utilization of emulsion technology to reduce the fat content and improve the nutritional profile of foods with oily continuous phases, such as spreads. [ABSTRACT FROM AUTHOR]

Abstract: The micelle nano-structures of octenyl succinic anhydride (OSA-starch) modified starches with different M w (weight average molecular mass) in aqueous solution were studied. The micelle aggregates observation, maximum dimension (r max) calculated from Pair Distance Distribution Function p(r) using General Indirect Fourier Transformation (GIFT) and radius of gyration (R g) obtained from Guinier fitting of the small angle X-ray scattering data indicated the obvious geometric disparity of micelles originated from different OSA-starches. The micelle presented increased monodispersity in more concentrated aqueous solution. The OSA-starch molecules with the highest M w formed the largest micelle. Hydrodynamic radius (R h) via dynamic light scattering of the micelle with the highest M w decreased in larger extent (from 80 nm to 46 nm), as well as more distinct change of R g/R h with increasing concentration, from which it could be deduced that the micelle conformation with higher M w was more flexible and more sensitive to the interparticle electrostatic repulsion. Moreover, the most compact interior structure formed within the micelle with the highest M w. The p(r) plots show typical profiles yielded from some oblate ellipsoid with a small subunit, long rod with a limited cross-section dimension and flattened prolate ellipsoid. It is anticipated that these nano-structures differences could be close related to stability and other properties of OSA-starch applied in oil-in-water system. [Copyright &y& Elsevier]

Abstract: β-Carotene formulations are very attractive as natural colorants as they provide additional value to the product due to their antioxidant and pro-vitamin activities. Application of β-carotene as colorants in beverages requires an appropriate formulation in order to stabilize the particles of β-carotene in suspension and provide the desired colour. This work presents a study of the formulation of β-carotene by precipitation from a pressurized ethyl acetate-in-water emulsion using modified OSA-starch refined from waxy maize as carrier material. Formulations of β-carotene with a high encapsulation efficiency of β-carotene (over 65% in most cases and as high as 90% with specific conditions), high antioxidant activity and a micellar particle size in the range of 300–600nm were obtained. The concentration of modified starch and the organic solvent/water flow ratio were the process parameters with most influence on product properties. [Copyright &y& Elsevier]

Cereals are subject to contamination by pathogenic fungi, which damage grains and threaten public health with their mycotoxins. Fusarium graminearum and its mycotoxins, trichothecenes B (TCTBs), are especially targeted in this study. Recently, the increased public and political awareness concerning environmental issues tends to limit the use of traditional fungicides against these pathogens in favor of eco-friendlier alternatives. This study focuses on the development of biofungicides based on the encapsulation of a curcumin derivative, tetrahydrocurcumin (THC), in polysaccharide matrices. Starch octenylsuccinate (OSA-starch) and chitosan have been chosen since they are generally recognized as safe. THC has been successfully trapped into particles obtained through a spray-drying or freeze-drying processes. The particles present different properties, as revealed by visual observations and scanning electron microscopy. They are also different in terms of the amount and the release of encapsulated THC. Although freeze-dried OSA-starch has better trapped THC, it seems less able to protect the phenolic compound than spray-dried particles. Chitosan particles, both spray-dried and lyophilized, have shown promising antifungal properties. The IC50 of THC-loaded spray-dried chitosan particles is as low as 0.6 ± 0.3 g/L. These particles have also significantly decreased the accumulation of TCTBs by 39%. [ABSTRACT FROM AUTHOR]

Beta-carotene (BC) microcapsules based on OSA-starch emulsions with different amount of sucrose were prepared to investigate the effects of sucrose on the physicochemical stability of BC microcapsules. BC loading amount, storage retention and particle size of water reconstituted microcapsules and emulsion before spray drying were studied. With the sucrose ratio increased in the wall material, the storage retention of the microcapsules powder and reconstituted powders increased as well. The free volume of the wall material decreased with increased sucrose ratio according to the SEM. Glass transition temperatures of the wall materials, the relative distribution of OSA-group in the powder determined by confocal Raman spectra microscope and the storage retention of BC of the water reconstituted microcapsules were also determined to interpret the mechanism of sucrose acting on the oxygen barrier effects of the wall materials. Phase separation was occurred in the high sucrose ratio group which probably the reason that the chemical stability of was increased. We also found that high ratio of sucrose can help to increase both physical and chemical stability of the water reconstituted microcapsules. When the wall material was composed by OSA-starch only, the carbonyl group distributed almost equally in the powder, which showed a porous matrix. After small amount of sucrose addition into the formula, the sucrose was stack in the free volume of the wall material matrix, which may not change the carbonyl group in the powder. With the sucrose ratio continually increased, there were phase separation occurred that the sucrose phase showed at the outer part of the powder, inducing significant changing of carbonyl group distribution. Image 103 • Chemically stable beta-carotene loaded microcapsules were prepared. The storage retention was more than 99% after 4 weeks under 60 °C oven. • Physically stable beta-carotene emulsion before spray drying and water reconstituted microcapsules were formed. • Phase separation was occurred in high sucrose ratio group. • Oxygen diffusion was limited both in powder and liquid state because of high sucrose ratio. • An oxygen barrier model and its mechanism were introduced. [ABSTRACT FROM AUTHOR]

• Structure & dynamics of phase-separated modified starch-sucrose blends are explored. • 13C NQS NMR allows to quantify the distribution of sucrose over the phases. • Positron lifetime and solid-state NMR confirm antiplasticization of starch by sucrose. • Spin diffusion NMR indicates that starch domains are very small (～ 5 nm). • Observed antiplasticization and phase separation impact physical stability. Interactions, organization and dynamics within phase-separated ternary blends of hydrophobically modified starch (HMS), sucrose and water are investigated using solid-state NMR and positron annihilation lifetime spectroscopy (PALS). Antiplasticization of HMS by sucrose is demonstrated by PALS and 1H NMR T 1 measurements. Selective solid-state 13C NMR experiments show that a large fraction of sucrose is in molecular contact with HMS even at high sucrose contents, indicating that the HMS-sucrose phase separation is only partial. Sucrose is observed to migrate away from the HMS-rich domains at temperatures that are above the lower T g , but still below the upper T g. 1H spin diffusion experiments indicate that phase separation occurs on a nanometric scale, in line with recent theory (Van der Sman, Food Hydrocolloids 87 , 360–370 (2019)). We infer that the nanoscale structure of the HMS-rich phase allows for intimate molecular contact between the HMS-rich and the sucrose-rich phases and explains the unusual dynamic behavior. [ABSTRACT FROM AUTHOR]

A new approach of fabricating temperature-responsive high internal phase emulsions (HIPEs) was established, based on controlling the hydrogen bonding in the system. These hydrogen bonds form between octenyl succinic anhydride modified starch (OSA-starch) and tannic acid (TA), as well as between the complexes of the two. The influence of system composition, pH, ionic strength, and temperature on the electrical, microstructural, and rheological properties of the HIPEs was determined. The HIPEs formed relatively firm gels at ambient temperature, but became considerably softer when heated above about 50 °C, which was attributed to weakening of the hydrogen bonds between the OSA-starch/TA complexes. The gels became firm again when cooled, which showed that they exhibited thermo-reversible rheological behavior. Encapsulation of β-carotene in HIPEs improved its chemical stability under UV-light exposure under all pH conditions. The edible HIPEs created in this study may therefore be useful where thermo-responsive gel-like systems are required. Image 1 • OSA-starch/Tannic acid complexes was used to stabilize the HIPEs. • Tannic acid increased the viscosity and shear modulus of the HIPEs. • HIPEs had temperature-responsive properties basing on hydrogen bonding interaction. • HIPEs was able to protect β-carotene from photodegradation. [ABSTRACT FROM AUTHOR]

In the search for oils of commercial interest that serve as new sources for the generation of cosmetic, pharmaceutical, or nutraceutical products, the green coffee beans oil (Coffea arabica L.) was studied. This research aimed to evaluate the oxidative stability of microencapsulated green coffee oil (Coffea arabica) by spray drying. The green coffee oil emulsions were produced by microfluidization using mesquite gum and octenyl succinic anhydride modified starches (OSA-starch) as wall-material. The particle size, polydispersity, and zeta potential on the microfluidized emulsions were optimized. The results showed that microfluidization had positive effects on the reduction of the emulsion droplets and the zeta potential, developing stable emulsions for both polymers. Then, the optimal microfluidization conditions were used to evaluate the impact of the spray drying conditions on the microencapsulation efficiency, morphology, and oxidation stability of the green coffee oil microcapsules under accelerated storage conditions (32% relative humidity (RH) at 25 °C). The microencapsulation efficiency was approximately 98% for both wall-materials. The morphology of the microcapsules showed spherical shapes and polydisperse sizes, a typical characteristic of spray-dried powders. The oxidative stability of the microcapsules was lower than the bulk green coffee oil (87.39 meq of O2/kg of oil), reaching values of 60.83 meq of O2/kg of oil for mesquite gum and 70.67 meq of O2/kg of oil for OSA-starch. The microcapsules produced have good potential for the development of nutraceutical foods or cosmetic formulations with adequate stability. [ABSTRACT FROM AUTHOR]

The response surface methodology, with a rotatable central composite design, is used in this study for optimizing spray drying process conditions to obtain a fine modified starch powder from "Dominico Hartón" plantains, which are chemically modified with 2‐octenyl‐succinic anhydride. A pilot‐scale spray dryer is used, and the following process factors are evaluated: (A) air inlet temperature (136–154 °C), (B) air outlet temperature (69–81 °C), and (C) rotational atomizer speed (17666–34333 rpm). The response variables are yield, moisture content, and functional properties such as water absorption index (WAI); water solubility index (WSI), swelling power (SP) and degree of substitution (DS). The factors B and C significantly influence the functional properties. The following are the optimal conditions from the process: factor (A), 150 °C; factor (B), 80 °C; and factor (C), 34 858 rpm, with the desirability of 56.7%. Under these optimal conditions, chemically modified plantain starch with desirable quality properties of low moisture content, water activity, and solubility index and high process yield, water absorption index, swelling power, and degree of substitution could be produced. [ABSTRACT FROM AUTHOR]

The in vivo slow digestion property of octenyl succinic anhydride modified waxy corn starch (OSA-starch) in the presence of tea polyphenols (TPLs) was studied. Using a mouse model, the experimental results showed an extended and moderate postprandial glycemic response with a delayed and significantly decreased blood glucose peak of OSA-starch after cocooking with TPLs (5% starch weight base). Further studies revealed an increased hydrodynamic radius of OSA-starch molecules indicating an interaction between OSA-starch and TPLs. Additionally, decreased gelatinization temperature and enthalpy and reduced viscosity and emulsifiability of OSA-starch support their possible complexation to form a spherical OSA-starch-TPLs (OSAT) complex. The moderate and extended postprandial glycemic response is likely caused by decreased activity of mucosal α-glucosidase, which is noncompetitively inhibited by tea catechins released from the complex during digestion. Meanwhile, a significant decrease of malondialdehyde (MDA) and increased DPPH free radical scavenging activity in small intestine tissue demonstrated the antioxidative functional property of the OSAT complex. Thus, the complex of OSAT, acting as a functional carbohydrate material, not only leads to a flattened and prolonged glycemic response but also reduces the oxidative stress, which might be beneficial to health.