The effect of octenyl succinic anhydride-modified chitosan coating on DHA-loaded nanoemulsions: Physichemical stability and in vitro digestibility

Octenyl succinic anhydride-modified chitosan (OSA-CS) was synthesized and applied as a coating material to enhance the stability of docosahexaenoic acid (DHA)-loaded nanoemulsion. Due to the presence of the positively charged OSA-CS coating, the nanoemulsion exhibited a high positive zeta potential and two different layers. Compared with natural CS-coated nanoemulsion, OSA-CS-coated nanoemulsion showed improved storage stability (physical and chemical stability) and stability against environmental stresses (ionic strengths, temperatures and pH). Besides, OSA-CS-coated nanoemulsion protected encapsulated DHA from simulated gastric fluid damage better than that of natural CS-coated nanoemulsion, suggesting that OSA-CS-coated nanoemulsion had the potential to deliver more DHA into the small intestine. In conclusion, based on the comparison of two coating materials, natural chitosan and OSA-CS, it was found that the encapsulated nutrient was better protected by the OSA-CS coating. Such a finding will provide insights to broaden the application of modified chitosan in food delivery systems.

Fabrication and characterization of dual-functional porous starch with both emulsification and antioxidant properties

Starchy materials with good antioxidant, emulsification and adsorption properties have potential applications in industry. To improve these properties, a Dual-functional porous starch was prepared through one-pot synthesis. In this case, octenyl succinic anhydride (OSA) and syringic acid (SA) were selected to modify the porous starch (PS) by esterification, with subsequent signals recorded by 1H NMR at 1.2 ppm and FT-IR at 1743 cm-1, indicating the formation of Dual-functional porous starch grafted by OSA and SA. N2 adsorption analysis further proved that the porous structure (2.9 m2g-1) was still maintained after modification. This was followed by measurements of droplet size distribution (34.18 ± 3.80 μm), zeta potential (-39.62 ± 1.89 mV) and emulsion index (85.10 ± 1.76 %), all of which indicated good emulsifying capacity. Meanwhile, results of radical scavenging assay proved that the Dual-functional porous starch had considerable antioxidant properties due to the introduction of SA groups. Besides, the Dual-functional porous starch also showed good resistance to digestion. These findings not only provide a novel strategy for constructing multi-functionalized starchy materials, but also open up potential applications of starch in the food and pharmaceutical industries.

Preparation, characterization and in vitro digestion of octenyl succinic anhydride-modified porous starch with different degrees of substitution

Octenyl succinic anhydride modified porous starch (OSA-PS) with degrees of substitution (DS) from 0.0123 to 0.0427 were prepared by aqueous phase method. From SEM, PS had a porous structure which showed a rough and corrosive surface after esterification with OSA. FT-IR revealed the characteristic peaks of OSA-PS at 1725 cm-1 and 1570 cm-1. From 1H NMR spectra, OSA-PS displayed extra chemical signal peaks at 0.85 ppm, 1.25 ppm and 1.96 ppm. These results fully demonstrated that OSA groups were successfully grafted onto PS. Furthermore, as DS increased, the specific surface area (5.6464 m2/g), pore volume (0.9959 × 10-2 cm3/g) and methylene blue adsorption capacity (24.3962 mg/g) of OSA-PS reached the maximum, while its relative crystallinity (26.8112 %) and maximum thermal decomposition temperature (291.96 °C) were the minimum. In vitro digestion studies showed that with the increase of DS, OSA-PS' contents of rapidly digestible starch and slowly digestible starch decreased from 9.06 % to 6.27 % and 28.38 % to 14.61 %, respectively. In contrast, its resistant starch had an increase in content from 62.56 % to 79.12%. The results provided an effective method for obtaining a double-modified starch with high specific surface area and anti-digestibility, thus broadening the industrial application of starch.

Synthesis, physicochemical and emulsifying properties of OSA-modified tamarind seed polysaccharides with different degrees of substitution

Octenyl succinic anhydride modified tamarind seed polysaccharides (OTSPs) with various degrees of substitution were first synthesized and characterized in this work. The structural, solid-state, solution and emulsifying properties of the OTSPs and the effect of the degree of substitution (DS) were investigated. The structural characterization confirmed the successful grafting of the OSA moiety into TSP and the chain extension of the OTSPs. The hydrophobicity of the modified polysaccharide molecules increased, the absolute value of the zeta potential increased, and the thermal stability decreased, which were positively or negatively correlated with the changes in DS. In contrast, the hydrolysis of polysaccharides in alkaline aqueous solution led to a decrease in molar mass and the rigidity of the molecules, which were not significantly related to DS. Particle size analysis showed that OTSPs tended to aggregate into relatively small agglomerates, which was confirmed by the results of morphological analysis. Most importantly, the instability indices of emulsions stabilized by TSP, arabic gum and OSA-starch were 0.521, 0.715, and 0.804, respectively, while for OTSPs this parameter was between 0.04 and 0.19 under the same conditions, indicating better physical stability of the OTSP-stabilized emulsions, especially for OTSP-30. Overall, OTSP has great potential as an emulsifier for oil-in-water emulsions, especially for emulsification and stabilization in food processing.

Octenyl succinic anhydride-modified amyloid protein fibrils demonstrate enhanced ice recrystallization inhibition activity and dispersibility

Octenyl succinic anhydride (OSA) modification of amyloid proteins fibrils (APFs) was employed to improve dispersibility and ice recrystallization inhibition activity. OSA mainly reacted with the amino groups of APFs without significantly changing morphology. OSA-modified APFs (OAPFs) had lower pI, carried more negative charges, and were more hydrophobic. OSA-modification showed a pH-dependent effect on the dispersibility of fibrils. At pH 7.0, OSA-modification improved dispersibility and inhibited heat-induced gelation of fibrils at weakened electrostatic repulsion. OAPFs were more prone to aggregation with lower dispersity at acidic pH values and demonstrated stronger IRI activity than unmodified fibrils at pH 7.0. Our findings indicate OSA-modification favors the industrial application of APFs as an ice recrystallization inhibitor with enhanced dispersibility.

Synthesis of octenyl succinic anhydride-modified levan and investigation of its microstructural, physicochemical, and emulsifying properties

In this study, levan from Bacillus licheniformis NS032 was modified in an aqueous medium by octenyl succinic anhydride (OSA), and the properties of the obtained derivatives were studied. The maximum efficiency in the synthesis reaction was achieved at 40 °C and a polysaccharide slurry concentration of 30 %. Increasing the reagent concentration (2-10 %) led to an increase in the degree of substitution (0.016-0.048). Structures of derivatives were confirmed by FTIR and NMR. Scanning electronic microscopy, thermogravimetry, and dynamic light scattering analyses showed that the derivatives with degrees of substitution of 0.025 and 0.036 retained levan's porous structure and thermostability and showed better colloidal stability than the native polysaccharide. The intrinsic viscosity of derivatives increased upon modification, while the surface tension of the 1 % solution was lowered to 61 mN/m. Oil-in-water emulsions prepared with sunflower oil (10 % and 20 %) by mechanical homogenization and 2 and 10 % derivatives in the continuous phase showed mean oil droplet sizes of 106-195 μm, while the distribution curves exhibited bimodal character. The studied derivatives have a good capacity to stabilize emulsions, as they have a creaming index ranging from 73 % to 94 %. The OSA-modified levans could have potential applications in new formulations of emulsion-based systems.

Improving the emulsification performance of adlay seed starch by esterification combined with ultrasonication and enzymatic treatment

In this study, superior modified starch was prepared using ultrasonic and enzymatic treatments to confirm the potential of using adlay seed starch (ASS) in Pickering emulsions. Octenyl succinic anhydride (OSA)-modified starches, such as OSA-UASS, OSA-EASS, and OSA-UEASS, were prepared using ultrasonic, enzymatic, and combined ultrasonic and enzymatic treatments, respectively. The effects of these treatments on the structure and properties of ASS were evaluated to elucidate their influence on starch modification. Ultrasonic and enzymatic treatments improved the esterification efficiency of ASS by changing its external and internal morphological characteristics and the crystalline structure to provide more binding sites for esterification. The degree of substitution (DS) of ASS modified by these pretreatments was 22.3-51.1 % higher than that of the OSA-modified starch without pretreatment (OSA-ASS). Fourier transform infrared and X-ray photoelectron spectroscopy results confirmed the esterification. Small particle size and near-neutral wettability indicated that OSA-UEASS was the promising emulsification stabilizer. The emulsion prepared using OSA-UEASS exhibited better emulsifying activity and emulsion stability and long-term stability for up to 30 days. These amphiphilic granules with improved structure and morphology were used to stabilize a Pickering emulsion.

Effects of the degree of substitution of octenyl succinic anhydride on the physicochemical characteristics of adlay starch

Impact of octenyl succinic anhydride (OSA) esterification on the structural, thermal, pasting, and emulsifying characteristics of adlay starch was investigated. The degree of substitution (DS) increased significantly from 0.008 to 0.025 with increasing OSA quantity, and the bands intensity at 1724 cm^-1 and 1572 cm^-1 in Fourier transform infrared spectroscopy increased with increasing DS. OSA modified starch showed unaltered orthorhombic diffraction pattern and morphological structure in native adlay starch, but gelatinization temperatures and enthalpy decreased significantly. Higher DS values lowered iodine binding capacity (from 1.37 to 0.77) and a shift in the maximum absorbance wavelength toward the shortwave direction was observed (from 530 nm to 510 nm). Significant increases were observed in peak, through, breakdown and final viscosities upon OSA esterification, while the pasting temperature decreased. Furthermore, contact angles increased significantly from 27.4° to 73.4° with increasing DS, and OSA-starch exhibited superior emulsion stability. Therefore, esterification with OSA effectively modified adlay starch to meet industrial demands and enhance its functional properties.

Pulsed electric field-assisted esterification improves the freeze-thaw stability of corn starch gel by changing its molecular structure

The influence of pulsed electric field (PEF) combined with octenyl succinic anhydride (OSA) on the freeze-thaw stability of corn starch gel was investigated. After five freeze-thaw cycles, the syneresis value of OSA starch treated with PEF-assisted esterification for 15 min was lower by 29.5 %, while that of OSA starch without PEF treatment was lower by 10.17 %, compared to that of native starch. Low-field nuclear magnetic resonance data showed that the introduction of OSA groups greatly increased the water-holding capacity of starch. Results from differential scanning calorimetry (DSC) and X-ray diffraction (XRD) showed that the PEF-assisted esterification markedly hindered the re-formation of the helical structure of starch during freeze-thaw cycles. Moreover, PEF-assisted esterification improved the viscoelastic properties of the starch gel. It is found that the freeze-thaw stability of the PEF-modified starch depends not only on the degree of substitution but also on the starch molecular fine structure. PEF-assisted OSA starch with a high degree of substitution, a low content of amylose, and a high content of short amylopectin chains were found to have high freeze-thaw stability. This study shows that PEF-assisted esterification is a promising technique that should be used for preserving the quality of frozen foods.

Preparation of octenyl succinylated kappa-carrageenan; reaction optimization, characterization, and application in low-fat vegan mayonnaise

Kappa-carrageenan (KC) esterification reaction with octenyl succinic anhydride was optimized using response surface methodology, leading to the production of a food-based emulsifier. Modified kappa-carrageenan (KC-OSA) with different degrees of substitution (DS) (0.023 and 0.045) was produced, and their functional and structural properties were investigated. The results from FTIR and ¹HNMR verified the successful occurrence of modification. The KC-OSA emulsions with both DS values were utterly stable after 30 days of storage, while KC failed to form emulsions. The viscosity, foaming properties, surface net charge, and gel opacity increased after modification and with an increase in its extent, while emulsion particle size and polydispersity index, gel melting temperature, and gel hardness decreased. Afterward, the KC-OSA (DS = 0.023) potential use was investigated as fat and egg yolk substitute in mayonnaise, which resulted in vegan mayonnaise samples with no phase separation after a month of storage at room temperature. Particle size measurements implied that the particle size of the mayonnaise sample was decreased with an increase in KC-OSA concentration. The results from the sensory evaluation showed that KC-OSA could be successfully implemented in low-fat vegan mayonnaise. The results from this study draw a bright horizon for the use of KC-OSA in the food industry.

Supramolecular structure of quinoa starch affected by nonenyl succinic anhydride (NSA) substitution

Quinoa starch granular structure as affected by nonenyl succinic anhydride (NSA) substitution was investigated by multiple approaches, including scattering, spectroscopic, and microscopic techniques. The modification had little impact on the morphology of starch granules. The NSA substitution was found mainly in the amorphous lamellae and amorphous growth rings. The NSA modification increased the thickness of the amorphous lamellae. The homogeneity of the ordered structure in the granules was improved, probably because the NSA modification reduced the amount of defects in the semi-crystalline growth ring. Compared to other chemical modifications such as acylation, succinylation was more effective in modifying the starch lamellar structure. A possible reaction pattern of NSA modification on quinoa starch is proposed, in which the NSA modification may follow the sequence of amorphous growth rings, the amorphous matrices among blocklets, amorphous and crystalline lamellae in semi-crystalline growth rings. This study provides new insights on the structural changes of starch granules induced by succinylation on the supramolecular level.

Study on the structure and physicochemical properties of fenugreek galactomannan modified via octenyl succinic anhydride

To improve the mechanical strength of borax-crosslinked fenugreek galactomannan hydrogels and broaden the application field of galactomannan-based hydrogels, fenugreek galactomannan (FG) was esterified via octenyl succinic anhydride (OSA), and the parameters affecting the esterification reaction were systematically studied. The optimum process for OSA-modified FG (OFG) was as follows: FG concentration 1.5 wt%, n (OSA): n (FG) = 2, n (4-dimethylamino-pyridine, DMAP): n (FG) = 4, and reaction time 12 h. Under this condition, the degree of substitution (DS) was 0.31, and the product yield was 115.05 %. Characterization of FT-IR, H¹ NMR, and HPLC confirmed that the OSA group was successfully introduced into the FG skeleton. The mechanical strength of borax crosslinked OFG hydrogel (OFGH) is 18 times higher than that of FG hydrogel. OFGH shows excellent self-healing, injectable properties and electrical conductivity. This will further expand the application of borax crosslinked galactomannan-based hydrogels in the fields of sensors, drug delivery, and wound dressing.

Revealing substitution priority and pattern of octenylsuccinic groups along the starch chain under a continuous mode

Octenylsuccinic (OS) groups distribution was considered random under traditional batch mode (BM) process due to excessive available octenyl succinic anhydride (OSA) at early stage, making the functionality optimization of OSA starch under restricted substitution degree (DS) difficult. To reveal the priority rule of substituent position at starch molecular level, a continuous mode (CM, dropwise OSA addition) was applied for OSA starch preparation. Initial OSA substitution was predominately at the branching points of amylopectin backbone, then successive at the branching points of shorter and longer chains with increasing DS. As DS increased over 1.49%, substitution started occurring along the chains and moved towards the non-reducing ends until DS reached 6.65%. At similar DS, more branching point substitutions occurred at CM starch, showing superior emulsifying property over BM starch. OSA substitution priority rule does exist under controlled OSA supply, which would facilitate OSA starch design with specific substitution pattern and favored functionality.

Physicochemical, rheological, and emulsification properties of nonenyl succinic anhydride (NSA) modified quinoa starch

Nonenyl succinic anhydride (NSA) modification could be an alternative to octenyl succinic anhydride (OSA) modification of starch to obtain a range of physicochemical and rheological properties and for emulsification applications. A series of NSA-modified quinoa starches in granular form with different degrees of substitution (DS) (0.0080, 0.0175, 0.0359, and 0.0548) were prepared. The NSA modifications reduced the gelatinization temperatures and frequency dependence of storage modulus (G'), while increasing the peak viscosity, gel hardness, and G'. The NSA-modified quinoa starches with medium DS were the most effective in stabilising Pickering emulsions. The droplet size of Pickering emulsions decreased first with increasing DS before increasing at the highest DS. Modified starch with a DS of 0.0359 had the highest emulsifying capacity. Apart from the commonly used octenyl succinic anhydride (OSA) modification, the NSA-modified starches could be potential candidates as efficient Pickering emulsion stabilizers.

Preparation and characterization of octenyl succinic anhydride modified waxy maize starch hydrolyzate/chitosan complexes with enhanced interfacial properties

The preparation and characterization of colloidal complexes based on octenyl succinic anhydride starch hydrolyzate (OSAS) and chitosan (CS) were conducted. Results showed that OSA-S/CS ratio (r) and pH significantly affected complex turbidities and yields. The highest turbidity and yield were obtained at r = 6:1 when pH was fixed, and at pH 6.5 when r was fixed. All complexes remained liquid-like except that formed at pH 6.5, which exhibited a gel structure due to the strongest complexation. OSA-S/CS complexes had intertwined core-shell microstructure and exhibited electrostatic interactions between COO^- and NH₃⁺ groups of OSA-S and CS, respectively. The complexes prepared at r = 6:1 and pH 6.0 exhibited the most suitable wettability (θ_ow = 91.97°) and interfacial adsorption dynamics. The compact lamellar network and intact cores of these complexes were also shown. This work provides profound and comprehensive information about the formation and physicochemical properties of OSA-S/CS complexes.

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.

Effects of the degree of substitution of OSA on the properties of starch microparticle-stabilized emulsions

An amphiphilic polymer of octenyl succinic anhydride (OSA)-modified starch microparticles (SMPs) was synthesized and used to stabilize emulsions. The effects of the degree of substitution (DS) on the physicochemical properties of OSA-modified SMPs and the stability of OSA-modified SMP-stabilized emulsions during a three-step in vitro digestion model were studied. The results showed that OSA esterification acted on the surface of SMPs and that the hydrophobicity of SMPs improved with increasing DS. In addition, the emulsion stability during storage and the changes in ionic strength were enhanced by increasing DS. Moreover, a higher DS also led to smaller oil droplets and more OSA-modified SMPs retained during intestinal digestion. Most importantly, the encapsulation efficiency and the bioaccessibility of curcumin in the emulsion during intestinal digestion were both enhanced significantly with the increase of DS.

Synthetic mechanism of octenyl succinic anhydride modified corn starch based on shells separation pretreatment

Herein, the synthetic mechanism of octenyl succinic anhydride (OSA) modified corn starch (OSCS) and granule shells (OSC_s) based on shells separation pretreatment (SSP) was investigated. High intensity peaks around 1720 and 1570 cm^-1 were observed for OSC_s in Fourier transform infrared (FTIR) spectra after SSP. OSC_s showed higher degree of substitution (DS) values (ranging from 0.128 to 0.170) than OSCS (0.121) determined by ¹H NMR. The average molecular weight (M_w) of OSA modified CS decreased, due to the introduction of OS groups. X-ray diffraction (XRD) indicated that esterification mainly took place in the amorphous regions of starch granules. X-ray photoelectron spectroscopy (XPS) revealed that a new peak corresponding to 1s orbital electrons of Na was obtained due to the introduction of OSA molecules. Meanwhile, lower surface DS and higher fluorescence intensity were noticed for OSC_s. Conclusively, SSP would significantly increase the reaction efficiency of OSA modification process of CS.

Structure and physicochemical properties of amphiphilic agar modified with octenyl succinic anhydride

A novel amphiphilic agar with high transparency and freeze-thaw stability was prepared using octenyl succinic anhydride (OSA). Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy confirmed that the hydrophobic OS groups were successfully introduced in OSA-modified agar (OSAR) backbone. The OSAR showed higher emulsion stability and oil loading capacity than the native agar (NA). Compared with gel transparency (47.1 %), syneresis (42.1 %) of NA, OSAR exhibited high gel transparency (80 %) and low syneresis (3.3 %) when the degree of substitution (DS) was 0.06 and 0.12, respectively. Meanwhile, the OSAR showed a decreased interface tension and average molecular weight after modification. Thermogravimetric analysis indicated the thermal stability of OSAR was decreased, while texture profile analysis showed the springiness of the OSAR gel was enhanced. Dynamic rheology measurements revealed the OSAR with low gel strength displayed more liquid-like properties. Moreover, the OSAR exhibited lower turbidity and melting temperatures than the NA.

Biodegradable sandwich-architectured films derived from pea starch and polylactic acid with enhanced shelf-life for fruit preservation

The development of biopolymer films is crucial for the replacement of conventional plastics. Tremendous effort is made to improve their performances by introducing biopolymers through the film manufacturing process. Herein, a sandwich-architectured film was proposed to efficiently improve the adhesion between the PS and PLA layers by using octenyl succinic anhydride-modified pea starch (OMPS) layer as the interlayer, leading to a highly mechanically enhanced interpenetrating network. Accordingly, the properties of the films were enhanced due to the synergism effect of sandwich architecture. In particular, the WVP value of the sandwich-architectured films (0.25 ∼ 0.89×10-10g·m-1·s-1·Pa-1) decreased more than 7-fold compared with the OMPS20 film, and the OP value of the sandwich-architectured films (0.256 ∼ 1.229×10-12cm3·m·m-2·s-1·Pa-1) decreased more than 10-fold in comparison to the PLA film. Benefitting from the characteristics investigated above, the films exhibited a favorable effect on strawberry storage. Overall, the fabricated eco-friendly sandwich-architectured films have shown great potential for biodegradable packaging applications.

Octenyl succinylation of kefiran: Preparation, characterization and functional properties

In this study, kefiran was esterified with octenyl succinic anhydride (OSA). The esterification reaction variables including pH (8.5), kefiran concentration (5% (w/w)), OSA concentration (12% (w/w)), temperature (~38 °C) and reaction time (~80 min) were found as optimum points to achieve the maximum degree of substitution (DS) (0.041 ± 0.002). Kefiran-OSA samples with DS of 0.021 (FDA suggested DS) and 0.041 (maximum DS) were prepared and compared with unmodified kefiran in all experiments. FTIR and ¹H NMR spectroscopies proved the grafting of OSA on kefiran structure. XRD analysis revealed that with increase in DS, the physical state of kefiran to be more amorphous. In addition, the esterification modification led to a decrease in the degradation temperature and an increase in the apparent viscosity based on the obtained data from thermal analysis and viscosity measurement. The results of the foaming and emulsifying properties confirmed the improvement in surface properties of the modified kefiran. The frequency sweep test illustrated that with an increase in DS, the viscoelastic behavior of the kefiran cryogels to be more viscous. It can finally be stated that the modification with OSA was a high potential strategy to extend the industrial applications of the kefiran.

Modulating the aggregation of myofibrillar protein to alleviate the textural deterioration of protein gels at high temperature: The effect of hydrophobic interactions

In this study, the strategy of utilizing a model hydrophobic molecule, octenyl succinic anhydride (OSA), to inhibit over-aggregation of MP during heating, aiming to alleviate high temperature-induced textural deterioration of MP gels, was proposed, and a series of experiments were conducted to verify the effectiveness. The results showed that the effect was positively dependent on the concentrations of OSA. The addition of OSA at a concentration of 4 g/kg to 24 g/kg delayed the gelation temperature of MP, as confirmed by the DSC results, and inhibited the aggregation of MP through hydrophobic interactions between OSA and MP, as revealed by fluorescence and FTIR spectroscopy. Furthermore, when the concentration of OSA increased from 4 g/kg to 12 g/kg, the controlled aggregation of MP improved the gel properties of MP formed at high temperature, but when the concentration reached 24 g/kg, the protein aggregation was too inhibited to form developed gel networks.

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.

Physicochemical properties of dodecenyl succinic anhydride (DDSA) modified quinoa starch

Quinoa starch granules were esterified with dodecenyl succinic anhydride (DDSA) to various degrees of substitution (DS) (0.0023-0.0095). Physicochemical properties and emulsification capacity of the modified starch were studied. Increasing DS increased the particle size, water solubility, and swelling power, while decreasing the gelatinization enthalpy change and relative crystallinity of the starch. The DDSA groups were suggested to be mostly located in the amorphous region of starch granules. With increasing DS, the viscosity and storage modulus (G') obtained from rheological analysis increased first and then decreased. The DDSA modified quinoa starch efficiently stabilized O/W Pickering emulsions and has some technical advantages compared to octenyl succinic anhydride (OSA)-modified quinoa starch. Increasing DS led to decreased droplet size of the emulsions and a higher capacity in stabilizing emulsions during storage for a period of 10 days. This study suggested the potential application of DDSA modified quinoa starch as an emulsifier in stabilizing Pickering emulsions.

Preparation and characterization of emulsion stabilized by octenyl succinic anhydride-modified dextrin for improving storage stability and curcumin encapsulation

In our study, octenyl succinic anhydride (OSA)-modified dextrin was prepared and characterized as a novel emulsifier to improve the stability of emulsion and curcumin encapsulation. Fourier-transform infrared spectroscopy demonstrated the occurrence of esterification between OSA and dextrin (M_w = 1.041 × 10⁴ g/mol). The absolute value of ζ-potential of OSA-dextrin increased (from 25.37 mV to 34.57 mV) with increasing OSA addition (from 0% to 8%), and then kept constant. Confocal laser scanning microscope results showed that the debranching and esterification of starch improved the oil droplets distribution and reduced the droplet size of emulsions. The emulsifying stability of emulsions coated by dextrin was greatly improved with OSA modification. The particle size of emulsion decreased significantly when the addition of OSA increased during storage. OSA-modified dextrin was in a position to increase encapsulation efficiency of curcumin. This research may increase the utilization of emulsions stabilized by OSA dextrin in food industry.

Dynamic high-pressure microfluidization assisting octenyl succinic anhydride modification of rice starch

Octenyl succinic anhydride (OSA) modified starch is widely used in food industries. In this study, rice starch (RS) was pretreated by dynamic high-pressure microfluidization (DHPM) and subsequently modified by OSA. The influence of DHPM on OSA modification of rice starch was investigated. Results showed that DHPM pretreatment enhanced the degree of substitution by changing the morphology and crystallinity of rice starch. Compared with the rice starch modified by OSA without DHPM pretreatment (OSA-RS), the DHPM-pretreated OSA starch (DHPM-OSA-RS) presented higher peak viscosity and lower pasting temperature. DHPM-OSA-RS also exhibited better emulsifying activity and emulsion stability. This study suggested that DHPM will provide an opportunity to change the physicochemical properties of starch, with the resulting starch being more suitable for chemical modification.

Evaluation studies on the combined effect of hydrothermal treatment and octenyl succinylation on the physic-chemical, structural and digestibility characteristics of sweet potato starch

In order to increase the degree of substitution (DS), a combination of heat-moisture treatment (HMT) and octenyl succinylation (OSA) was used to modify sweet potato starch (SPS). The content of OSA had significant influence on the DS of starch, and DS of HMT OSA-modified SPS (HOSA-SPS) was higher than that of OSA-modified SPS (OSA-SPS), indicating that prior HMT could enhance the reaction. HOSA-SPS showed higher contents of SDS and RS in comparison with OSA-SPS as OSA concentration was beyond 6%. HMT decreased swelling power of starch while OSA modification had a contrary role (p < 0.05). Scanning electron microscopy (SEM) showed starch was destroyed by OSA modification while HMT had slight effect on the structure. X-ray diffraction (XRD) indicated that crystal type of starch was transformed from C- to A-type resulted from HMT, and remained unchanged by OSA modification. The onset, peak, and conclusion gelatinization temperatures of starch increased by HMT and decreased by OSA modification (p < 0.05).

Rheological properties of reduced fat ice cream mix containing octenyl succinylated pearl millet starch

The octenyl succinyl anhydride (OSA) esterified pearl millet (Pennisetum typhoides) starch was evaluated as fat replacer in soft serve ice cream in comparison to other fat replacers viz. inulin, whey protein concentrate-70 and commercial starch. During temperature sweep test, the yield stress and flow behaviour index of un-pasteurized ice cream mixes increased as the temperature increased from 40 to 80 °C, while the consistency index decreased. Consistency index of aged ice cream mixes containing 2% fat replacer was higher as compared to mixes with 1% level. The aged ice cream mixes exhibited non-Newtonian behaviour as flow behaviour index values were less than one. Apparent viscosity (at 50 s^-1 shear rate) of control as well as ice cream mix containing 1% OSA-esterified pearl millet starch samples was 417 and 415 mPas, respectively and did not differ significantly. The overrun of the ice cream (with 5 and 7.5% fat) containing 1 and 2% of above fat replacers ranged between 29.7 and 34.3% and was significantly lower than control (40.3%). The percent melted ice cream was also low for the ice creams containing 2% of above fat replacers at 5% fat content as compared to control. However, sensory acceptability and rheological characteristics of reduced fat ice creams containing 1.0 and 2.0% OSA-esterified pearl millet starch were at par with other fat replacers under the study. Thus, OSA-esterified pearl millet starch has potential to be used as fat replacer in reduced fat ice cream.

Rheological properties of reduced fat ice cream mix containing octenyl succinylated pearl millet starch

The octenyl succinyl anhydride (OSA) esterified pearl millet (Pennisetum typhoides) starch was evaluated as fat replacer in soft serve ice cream in comparison to other fat replacers viz. inulin, whey protein concentrate-70 and commercial starch. During temperature sweep test, the yield stress and flow behaviour index of un-pasteurized ice cream mixes increased as the temperature increased from 40 to 80 °C, while the consistency index decreased. Consistency index of aged ice cream mixes containing 2% fat replacer was higher as compared to mixes with 1% level. The aged ice cream mixes exhibited non-Newtonian behaviour as flow behaviour index values were less than one. Apparent viscosity (at 50 s^-1 shear rate) of control as well as ice cream mix containing 1% OSA-esterified pearl millet starch samples was 417 and 415 mPas, respectively and did not differ significantly. The overrun of the ice cream (with 5 and 7.5% fat) containing 1 and 2% of above fat replacers ranged between 29.7 and 34.3% and was significantly lower than control (40.3%). The percent melted ice cream was also low for the ice creams containing 2% of above fat replacers at 5% fat content as compared to control. However, sensory acceptability and rheological characteristics of reduced fat ice creams containing 1.0 and 2.0% OSA-esterified pearl millet starch were at par with other fat replacers under the study. Thus, OSA-esterified pearl millet starch has potential to be used as fat replacer in reduced fat ice cream.

Preparation, characterization and antibacterial activity of octenyl succinic anhydride modified inulin

Octenyl succinic anhydride modified inulin (In-OSA) was synthesized via chemical modification of inulin with octenyl succinic anhydride (OSA). The esterification of inulin with OSA was confirmed by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and degree of substitution (DS) calculation. Antibacterial activity of In-OSA against Staphylococcus aureus and Escherichia coli was investigated by minimum inhibitory concentration (MIC) and inhibition rate determination. The results showed that inhibition rates against both E.coli and S. aureus increased with the increase of the In-OSA concentration. And the MICs against E. coli and S. aureus were 1% and 0.5% (w/v), respectively. The antibacterial mechanism was analyzed with the results of the proteins and nucleic acids leakage, SEM and negative staining transmission electron microscopy (TEM). Both the leakages of proteins and nucleic acids increased with the increase of the In-OSA concentration. The leakage occurred mainly in the early stage which indicated that cell membrane and wall were destroyed by In-OSA quickly. The images of SEM and negative staining TEM suggested that the cell membranes and cell walls of S. aureus were damaged more severely and even destroyed completely; but only pores appeared on the surface of E. coli.

A 3-week dietary safety study of octenyl succinic anhydride (OSA)-modified starch in neonatal farm piglets

Octenyl succinic anhydride (OSA)-modified starch functions as both an emulsifier and emulsion stabilizer in foods, and is intended for use in infant formula, follow-on formula, and formulae for special medical purposes. These formulae predominantly include extensively hydrolyzed protein or free amino acids, rather than intact protein, which otherwise would provide emulsifying functionality. The study objectives were to evaluate (1) the safety of OSA-modified starch after three weeks of administration to neonatal farm piglets, beginning 2 days after birth and (2) the impact of OSA-modified starch on piglet growth. OSA-modified starch was added to formula at concentrations of 2, 4, and 20 g/L. The vehicle control, low-dose, and mid-dose diets were supplemented with Amioca™ Powder to balance the nutritional profiles of all formulations. There were no test article-related effects of any diet containing OSA-modified starch on piglet growth and development (clinical observations, body weight, feed consumption), or clinical pathology parameters (hematology, clinical chemistry, coagulation, urinalysis). In addition, there were no adverse effects at terminal necropsy (macro- and microscopic pathology evaluations). Therefore, dietary exposure to OSA-modified starch at concentrations up to 20 g/L was well tolerated by neonatal farm piglets and did not result in adverse health effects or impact piglet growth.