Acetylated Starch Research Articles

Complexation characteristics between acetylated starch and soy protein isolates and intestinal digestion behavior of the polymers encapsulated active compound

The interaction between acetylated starch (AS) and soy protein isolates (SPI) was investigated under different pH conditions, and their corresponding physicochemical properties of the complexes were investigated. This study found that, at pH9.0, the β-turn structure of the protein in the complexes changed into Random coil with the highest ratio, and the thermal stability of the complexes was found to be reduced, which was contributed to the destruction of the crystalline region to a large extent. Meanwhile, the confocal laser scanning microscopy (CLSM) results showed that the complexes demonstrated a dispersed phase at pH5.0, and the SPI structure unfolded maximum at pH9.0. Following the determination of the changes in the rheological property under the existence of NaCl and urea, it was proposed that electrostatic interaction was the major interaction force for all the three complexes. However, hydrophobic and hydrogen bonding forces also seemed to play a more important role for AS/SPI-pH9 complexes than either AS/SPI-pH2 or AS/SPI-pH5 complexes. Complexation significantly increased encapsulation efficiency and loading capacity of curcumin compared to their corresponding individual polymer, followed by a reduced release kinetics at intestinal fluid but not at simulate gastric fluid stage via an in vitro digestion.

Surface adhesion and physical properties of modified TPS and PBAT multilayer film

Starch-based materials are susceptible to moisture, leading to sticking and instability. Coating with hydrophobic biodegradable materials improves their stability. This research produced multilayer biodegradable packaging based on thermoplastic cassava starch (TPS) blended with poly(butylene adipate-co-terephthalate) (PBAT). TPS/PBAT mixtures were produced via blown film extrusion before coating with PBAT solution. Different TPS content (up to 80 %) and types of modified cassava starch namely native starch (NS), hydroxypropylated starch (HS), acetylated starch (AS), and octenyl-succinated starch (OS) were investigated for micro and chemical structure, delamination, and PBAT coating deposition on TPS/PBAT multilayer film. IR spectra of the peak at 3300 cm−1 (O-H stretching of TPS) was absent after coating, suggesting reduced TPS content on the film surface, while 1717 cm−1 (CO from carbonyl groups of PBAT), became sharper, indicating that PBAT deposition covered the film surface. The X-ray diffractogram showed a 2θ peak located at 24.4° (starch crystallinity) in the coated NS film; however, the peak was absent in coated HS, AS, and OS films because bulky chemical-grafted modified starch prevented molecular arrangement. Hydrophilic NS showed delamination and film substrate swelling after 60 s of direct contact with a sessile drop of water, indicating poor affinity. Hydrophobic-modified AS and OS significantly improved affinity with the PBAT coating layer giving a higher contact angle (105–112°), preventing delamination and substrate swelling and indicating increased water resistance. AS and OS (60 %) had higher shrinkage (23.78 % and 47.33 %) and a thicker coating layer (11.51 and 10.35 µm) due to greater polymer-solvent interaction. Hydrophobic-modified starch successfully improved the interaction between film layers and increased PBAT deposition.

Controlling sodium chloride concentration modulates the supramolecular structure and sol features of wheat starch-acetylated starch binary matrix

The sol performance of wheat starch (WS) matrix incorporating acetylated starch (AS) is crucial for the processing and quality features of wheat products. From a supramolecular structure view, how regulating salt (sodium chloride) concentration modulates the sol features, e.g., pasting, zero-shear viscosity (ZSV) and thixotropy of WS-AS binary matrix was explored. Compared to the salt-free counterpart, the saline matrices exhibited a delayed pasting profile and a decreased viscoelasticity. Thereinto, the sol at 0.02 M NaCl exhibited the smallest ZSV (23,710 Pa·s) and the greatest in-shear recovery ratio (33.7 %). Such variations could be attributed to the weakened coil-helix, nematic-smectic and isotropy-anisotropy transitions from a side-chain liquid-crystalline perspective. Meanwhile, the correlation length (ξ) and radius of gyration (Rg) obtained from small angle X-ray scattering analysis were increased by 5.2 and 9.6 Å respectively, which disclosed a restrained entanglement and an enhanced chain mobility. These results would provide a reference for the design of fluid/semisolid products with optimized qualities.

Investigation of ultrasound-assisted starch acetylation by single- and dual- frequency ultrasound based on rheology modelling, non-isothermal reaction kinetics, and flow/acoustic simulation

To achieve wheat starch acetylation (AC) with a high degree of substitution (DS), the acetylation process was carried out using various ultrasonication frequencies, including 25 kHz, 40 kHz, and 25 + 40 kHz. In the second step, wheat starch's ultrasound-assisted acetylation (UAA) is simulated using various approaches including the rheology models, non-isothermal reaction kinetics, and flow/acoustic modelling. The computational fluid dynamics (CFD) simulation solves the non-linear acoustic governing equation to determine the flow field and the amount of delivered ultrasound energy. The acetylated starch increased peak and final viscosity, with the highest values observed for the 25 + 40 kHz frequency than other single frequencies (25 kHz and 40 kHz). The viscosity of the starch is specified based on the experimental data using Herschel–Bulkley, power law, and Casson rheology models. According to differential scanning calorimetry (DSC) analysis, the gelatinization parameters and enthalpy of gelatinization (ΔHgel), were found to be lower in acetylated starches at the frequency of 25 + 40 kHz compared to those at frequencies of 25 kHz and 40 kHz, as well as native starches (NS). Moreover, the gelatinization process is examined by implementing the non-isothermal reaction kinetics to obtain the activation energy and reaction order. Based on the results obtained, implementing sonication at 25 kHz reduces the activation energy by 70.3 % compared to native starch. However, the same parameter is obtained to be 69.9 % and 67.1 % for the application of 40 and 25 + 40 kHz transducers, respectively. Additionally, during the sonication treatment, the yield shear stress increases between 24.1 and 31.8 %, based on the applied frequency. Morphology analysis determined by scanning electron microscopy (SEM) revealed that the surfaces and small granules underwent more damage in acetylated starches at frequencies of 25 kHz and 40 kHz. However, in acetylated starches at 25 + 40 kHz, the larger granules were more affected than the smaller ones.

Incorporating acetylated starch regulates the structure and sol-gel performance of wheat starch-based binary system

The sol-gel performance of wheat starch (WS) is of great importance for the processing and quality management of flour-based products. Herein, how acetylated starch (AS) inclusion modulates those properties of wheat starch-based system was understood using different techniques, e.g., rheological analysis and X-ray diffraction (XRD). Compared with WS alone, the resultant WS-AS binary system exhibited lower setback viscosity (corresponding to inhibited starch retrogradation as verified by XRD), zero-shear viscosity, moduli, and gel strength, accompanied by a suppressed sol-gel transition. Also, from thixotropy tests, the binary system with AS (WS-8%AS) presented the weakest thixotropy in hysteresis loop and a greater in-shear recovery property (as indicated by the three interval thixotropy test (3-ITT)), and the systems containing 6%–8% AS were proved to show good sol-gel properties. The property improvement could be related to the inhibited retrogradation, according to correlation analysis. In addition, the gel freeze-thaw stability of WS-AS systems was reduced as compared to WS, probably related to phase separations. The present information would facilitate the design of wheat starch-based matrices with regulated quality attributes.

Method of Starch Acetylation and Use of Acetylated Starch as Polymer in Pharmaceutical Formulations

Starch is used as a key polymer in pharmaceutical industries since long back for various purposes such as binder, disintegrating agent, bulking agent, film former and many more. But as per the purpose of dosage forms it’s used get changed. Currently scientists are more focused on controlled and sustained release dosage forms. Since, native starch does not meet up the demand of controlled or sustained release, so there is need of modifying the polymer as per dosage form requirement. Modification of starch can be done by physical, chemical, enzymatic, and genetic method. Among all, the current article is focusing on chemical modification of starch, especially the acetylation. Acetylation of starch can be done using different acetylating agent such as acetic anhydride (AA), and glacial acetic acid etc. and sodium hydroxide (NaOH), pyridine and sulphuric acid etc as a catalyst. The native structure of starch can be less efficient, since its functional properties are less stable to process condition such as high temperature, shear stress and exposure to acidic media, which decreases its use in industrial application. Acetylated starches facilitate higher stability and resistance to retrogradation or crystallization, enhanced granular size, swelling power, and water absorption capacity, which provides good flow and compression properties. It reduces the pasting temperature and solubility. It makes the acetylated starch as a good candidate for customizing the overall performance of native starch, which may be used as the controlled release or sustained release polymer in pharmaceutical dosage form.

Effect of Interphase Properties on Isothermal and Non-isothermal Crystallization Behavior of Poly(lactic acid)/Acetylated Starch Blends.

The effect of interphase properties on the crystallization behavior of blends of poly(lactic acid) (PLA)/acetylated starch (AS) with different degrees of substitution (DSs) was investigated. Under isothermal crystallization conditions, the rate of crystallization was higher for PLA/DS0.5 and lower for PLA/DS1.5 and PLA/DS2.5 when compared to PLA. In contrast, non-isothermal crystallization behavior indicated a slower rate of crystallization of PLA/DS0.5 and a faster rate of crystallization of PLA/DS1.5 and PLA/DS2.5 compared to PLA at the highest cooling rate (5 °C/min). The potential relationship between crystallization behavior and interphase properties and interphase thickness and formation of rigid amorphous fraction in the interphase, was investigated. The formation of a rigid amorphous fraction in PLA/DS1.5 and a thick interphase in PLA/DS2.5 prevented the formation of crystals on the dispersed phase and interrupted the crystallization under isothermal conditions. Hydrogen bonding in the PLA/DS1.5 blend and hydrophobic interactions in the PLA/DS2.5 blend may facilitate the crystallization at high cooling rates under non-isothermal conditions. Small-angle X-ray scattering analysis revealed the presence of a smaller lamellar structure in PLA/AS blends. The largest amorphous phase among blends was observed for the PLA/DS1.5 blend, which can be attributed to the hydrogen bonding in the interphase region of this blend.

Organocatalytic acetylation of pea starch: Effect of alkanoyl and tartaryl groups on starch acetate performance

Organocatalytic acetylation of pea starch was systematically optimized using tartaric acid as catalyst. The effect of the degree of substitution with alkanoyl (DSacyl) and tartaryl groups (DStar) on thermal and moisture resistivity, and film-forming properties was investigated. Pea starch with DSacyl from 0.03 to 2.8 was successfully developed at more efficient reaction rates than acetylated maize starch. Nevertheless, longer reaction time resulted in granule surface roughness, loss of birefringence, hydrolytic degradation, and a DStar up to 0.5. Solid-state 13C NMR and SEC-MALS-RI suggested that tartaryl groups formed crosslinked di-starch tartrate. Acetylation increased the hydrophobicity, degradation temperature (by ~17 %), and glass transition temperature (by up to ~38 %) of pea starch. The use of organocatalytically-acetylated pea starch with DSacyl ≤ 0.39 generated starch-based biofilms with higher tensile and water barrier properties. Nevertheless, at higher DS, the incompatibility between highly acetylated and native pea starches resulted in a heterogenous/microporous structure that worsened film properties.

Hydroxypropylation and acetylation of rice starch: effects of starch protein content.

The online version contains supplementary material available at 10.1007/s10068-022-01106-y.

Preparation and characterization of acetylated starch mediated silver nanoparticles: The effect of solution ratio and time-varying exposure

Abstract Plastic packaging is widely used in food industry to protect and maintain food freshness. However, plastic packaging also contributes to solid waste problem and can become the contamination area of microbial activities which in turn affecting the shelf-life of the food product and may causing food-borne illness towards consumer. Thus, the demands on biodegradable polymer as plastic packaging has grown widely especially among the food industry. The employment of silver nanoparticles (AgNPs) can improve physical properties of biopolymer as well as promoting antimicrobial properties on the plastic packaging. The aim of this study is to synthesize of AgNPs by utilising acetylated starch (AS) as reducing agent with different parameters via microwave irradiation method. The effect of different ratio of acetylated starch and microwave time-varying exposure is evaluated. The synthesized silver nanoparticles were characterized via UV-VIS spectroscopy (UV-VIS), X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) analysis. The absorbance peak emerges at 420nm on UV-VIS shows that silver nanoparticles is successfully produced. 15 minutes microwave time exposure and 1:1 ratio is identified as the optimum condition to produce silver nanoparticles. The peak emerges on FTIR spectra shows the involvement of starch in reduction process in synthesizing AgNPs. The XRD results shows the amorphous structure of starch and crystalline peak of silver appear in 2Θ regions 37.4°, 43.4°, 63.1° and 75.7°. In conclusion, the significant outcome from the study is the AgNPs were successfully synthesized via microwave irradiation method and be a function of time varying exposure and acetylated starch ratio.

Green synthesis of acetylated maize starch in different imidazolium carboxylate and choline carboxylate ionic liquids

This work demonstrates that acetylated maize starches (AMS) with varied degree of substitution (DS, 0.26–2.63) was synthesized in ionic liquids (ILs) (imidazolium chloride, imidazolium carboxylate and choline carboxylate) at 85 °C without catalyst. The DS of AMS and reaction efficiency increased with decreasing alkyl chain length of cations or anions, while decreased as the choline cation replaced the imidazolium cation and the chloride anion replaced the acetate anion. The AMS synthesized in imidazolium-based ILs exhibited much higher hydrophobicity and thermal stability than the native starch. Rheological properties of ILs and ATR-FTIR analysis of acetic anhydride/ILs mixtures indicated that a shorter alkyl side chain or the combination of an imidazolium cation and an acetate anion gave ILs lower viscosities and weaker interactions between acetic anhydride molecules, which favored the acetylation of starch. These findings provide insights into the design of green processes to modify starch and the application of acetylated starch.

Karakteristik Pati Talas Banten yang Dimodifikasi Menggunakan Asetat Anhidrida

Taro beneng (Xanthosoma undipes k.koch) is a tuber plant originating from Pandeglang. Taro tubers have a high starch content so they are the potential to be used in various industrial applications such as in the fields of food, textiles, paper, and others. In general, the use of natural starch for the industry has disadvantages related to its Physico-chemical characteristics. For a wider application, starch needs to be modified in order to have certain characteristics that are suitable for a certain application. In this study, a starch modification was carried out by the acetylation method using acetic anhydride. The independent variables used in this study were the ratio of acetic anhydride/dry starch (g/g): 0, 5, 10, 20%, while the dependent variables were % acetyl, degree of acetylation, swelling power, and solubility. The acetylation reaction was carried out at 35°C for 30 minutes. The results showed that starch acetylation using an acetic anhydride/starch ratio of 10 g/50 g resulted in percent acetylation (% acetyl) and degree of substitution (DS) were 4.3% and 0.16%, respectively. The highest swelling power value was 5.2 g/g, while the highest acetyl starch solubility was 1.6% which was obtained on acetylation using an acetic anhydride/starch ratio of 5/50 g/g.

Study of the Performance of Particles Based on Modified Starches Containing Potassium Sorbate and Incorporated into Biodegradable Films: Physicochemical Characterization and Antimicrobial Action

Ultrasound technique was used to produce native and acetylated cassava starch particles containing potassium sorbate (KS). In order to obtain an active packaging, films with addition of native starch particles containing KS (NKSPF) or added with acetylated starch particles containing KS (AKSPF) were formulated. As control systems, films without KS (CF) or added with KS that was not retained in particles (KSF), were produced. The NKSPF and AKSPF microstructure was consistent with composite materials. Tensile test revealed that CF and KSF were ductile and extensible (stress at break (σb) 2.8–2.5 MPa and strain at break (εb) 284–206%), while NKSPF and AKSPF were more resistant films with higher Young’s Modulus (148–477 MPa) and σb (3.6–17 MPa) but lower εb (40–11%). Moreover, NKSPF and AKSPF developed lower Yellowness Index (6.6–6.5) but higher opacity (19–23%) and solubility in water (31–35%) than KSF (9, 10.8% and 9%, respectively). It was observed that KSF and NKSPF moderately reduced the Zygosaccharomyces bailii growth while AKSPF showed the highest yeast inhibition, three Log-cycles, compared to CF. Additionally, FTIR spectroscopy revealed intensified interactions between KS and modified starch. It was concluded that starch sonication and acetylation were useful modifications to produce particles carrier of KS that improved the physical and antimicrobial performance of active films.

Preparation and characterization of chemically modified high amylose maize starch-ascorbyl palmitate inclusion complexes in mild reaction condition

Acetylation (0.48, 1.03, and 2.06%) and oxidation (0.48, 0.97, and 1.91%) of high amylose maize starch (HS) were used to encapsulate ascorbyl palmitate (AP). The V-amylose inclusion complexes could be prepared without pre-autoclaving HS. AP could be effectively encapsulated into modified HS (3.43–6.86%), and the modified complexes exhibited increased solubility and stability in an aqueous environment than the unmodified complex. AP in modified complexes exhibited similar stability against light and oxidation with the unmodified complex. Both modifications decreased the crystalline area, peak melting temperature, and enthalpy. Accordingly, the stability of AP in modified complexes against heat treatment was reduced. This study could expand the useable range of high amylose starch inclusion complex with AP and other ligands, especially in an aqueous environment.

Structural dependence of the molecular mobility in acetylated starch

In this study, the molecular mobility of acetylated starch (AS) with degree of substitution (DS) 1.5 and 3, representing partial and complete substitution of hydroxyl groups with acetyl groups, was investigated. The glass transition region and the onset of long-range cooperative molecular motions were examined using temperature-modulated-DSC (TMDSC). A potential analogy between the relaxation time of hole formation and the α-relaxation time was observed. The deviation in the temperature dependence of the α-relaxation time from the Arrhenius relationship, obtained with the fragility index, revealed differences according to DS. The cooperative rearranging region (CRR) characteristics differed according to DS and estimation method. Smaller size of the CRR for AS with DS 3 compared to AS with DS 1.5 suggest disruption of hydrogen bonds at high acetylation level. TMDSC experimental data at moderate temperature and predictions and SS-NMR results at ambient temperature, indicate different mobility of AS according to DS and temperature conditions.

Antioxidant and antibacterial activities of cassava starch and whey protein blend films containing rambutan peel extract and cinnamon oil for active packaging

Blending of cassava starch and whey protein isolate (WPI) films containing plant extracts showed modified properties and release behaviors. Effects of native starch (NS) and acetylated starch (AS) on film properties, antioxidant and antibacterial activities were investigated. WPI and WPI-starch films contained ethanolic fractions of rambutan peel extract (RPE) and cinnamon oil (CO). Mechanical, physical and water barrier properties of blend films depended on starch type and contents. Corilagin and (E)-cinnamaldehyde were the highest active components in RPE and CO, respectively. FTIR revealed hydrophobic interaction and hydrogen bonding between starch-protein-polyphenols. Protein conformation was altered giving modified amide I and amide II bands. Active compounds reduced water vapor permeability depending on starch types that governed CO dispersion. Starch, particularly AS, enhanced release of polyphenols and DPPH· scavenging activity in water and 50% ethanol. Antibacterial activity of the blend films differed between in vitro (disc diffusion method) and real food (salami) and was governed by the phenolic release and food components, respectively. WPI films showed the lowest in vitro antibacterial activity but the highest efficacy to delay microbial growth in salami. Release mechanism controlled the antioxidant capacity of active protein-starch films, whereas antibacterial capacity in foods strongly depended on food matrix components.

Effect of Sustainable Chemical Modifications on Pasting and Gel Properties of Sorghum and Cassava Starch

Starch isolated from two different sorghum hybrids and a commercial cassava starch were modified in order to assess the improvement in rheological and thermal properties that could be produced by sustainable methods. Modifications were acetylation with acetic anhydride, hydrolysis with acetic acid, and esterification with octanoyl chloride. All sorghum starch paste exhibited higher syneresis than cassava ones and acetylation slightly improved water retention. In general, pasting profiles were significantly altered throughout modifications and the paste textural properties and rheological results suggested a physical gel behavior. Cassava and white sorghum unmodified gels showed higher values of textural parameters than those of brown sorghum. The flow data were adequately fitted by the power-law model (R2 > 0.96) with flow behavior index < 1. The acetylation, acid treatment, and octanoyl esterification of cassava and sorghum starch resulted in significant changes in water interaction, indicating a wider range of properties.

Biofilm Based on Modified Sago Starch: Preparation and Characterization

Biofilms made from modified sago starch to improve the mechanical and physical properties have been studied. This study aimed to prepare and characterize biofilms from sago starch and modified sago (acetylation, oxidation, cross-link and precipitation). Modified of sago starch was prepared by some methods: precipitation using ethanol as solvent, acetylation modified of sago starch using acetic anhydride, oxidation modification using hydrogen peroxide and cross-link modification using sodium acetate. Biofilms were made from modified sago using glycerol with a concentration of 1.0% weight, where glycerol acts as a plasticizer to impart the thermoplasticity of the starch film. Biofilm made from native sago was then compared to biofilm from modified sago starch. The effects of modified sago starch to the biofilm were measured on its moisture contents, contact angle value, mechanical properties such as elongation and tensile strength. The chemical structures were evaluated by Fourier-transform infrared spectroscopy (FTIR) and morphology of biofilm were measured by Scanning Electron Microscope (SEM). The optimum condition of modified sago starch used in biofilm in this study is by acetylation. The result show that modified acetylation of sago starch can improve the properties of biofilm Keywords: biofilms, sago, acetylation, oxidation, cross link, SEM, FTIR

Poly(lactic acid)/acetylated starch blends: Effect of starch acetylation on the material properties

This study investigated the acetylation of starch to improve its processability and compatibility with poly(lactic acid). The temperature at the maximum rate of degradation increased by 3.2% for poly(lactic acid) blends containing acetylated starch degree of substitution 2.5 compared to the blend containing neat starch. A biphasic morphology with distinct dispersed phase was predicted and observed experimentally for all blends except the blend containing acetylated starch degree of substitution 3. Acetylated starch induced plasticization and nucleation for all degree of substitution. The blend containing acetylated starch degree of substitution 2.5 had higher tensile strength (26%), and toughness (29%) compared to the blend containing neat starch. The superior mechanical properties of the blend containing acetylated starch degree of substitution 2.5 are attractive for medical implant applications. The continuous microstructure and transparency characteristics of the blend containing acetylated starch degree of substitution 3 are attractive for packaging applications.

Controlled biodegradability of functionalized thermoplastic starch based materials

The present work focuses on the preparation and characterization of biodegradable materials based on plasticized and chemically modified starch. During the experiments, the morphology, properties and biodegradability of the starch materials were influenced by the functionalization (acetylation, propionation) of the starch, different processing procedures and the use of plasticizers. The starch materials were prepared by either solution casting or melt mixing or by the combination of the two procedures, which strongly affected the degree of the material plasticization, its homogeneity, and the final morphology. FTIR spectroscopy qualitatively proved the esterification of starch by the intensity of signals associated with esters groups. The thermogravimetric analysis confirmed a gradual reduction in the water content proportional to the acetylation of starches, as well as noticeable changes in their thermal properties at the higher degree of substitution (DS). Signal intensities and weight losses derived from FTIR and TGA, respectively, were well correlated with DS. The morphological changes of the polysaccharide materials were visualized by microscopy techniques. The biodegradation rate of prepared materials was expressed as the percentage of carbon mineralization and was significantly retarded as a function of the starch acetylation. A remarkable effect of the material processing, the presence of plasticizers, and the propionation of the starch on biodegradation has been found.