Effects of tamarind seed polysaccharide on gelatinization, rheological, and structural properties of corn starch with different amylose/amylopectin ratios

Elucidating the influence and mechanism of different phenols on the properties, food quality and function of maize starch

This study discusses interaction differences between three phenols (protocatechuic acid, naringin and tannic acid) and starch helix, investigates influences of phenols at different doses on properties of maize starch, and further determines their effects on quality and function of maize-starchy foods. Simulated results indicate variations of phenolic structure (phenolic hydroxyl group amount, glycoside structure and steric hindrance) and dose induce phenols form different complexes with starch helix. Formation of different starch-phenols complexes alters gelatinization (1.65-5.63 J/g), pasting form, water binding capacity (8.83-12.69 g/g) and particle size distribution of starch. Meanwhile, differences in starch-phenols complexes are reflected in fingerprint area (R1045/1022: 0.920 to 1.047), crystallinity (8.3% to 17.0%), rheology and gel structure of starch. Additionally, phenols change texture and color of cold maize cake, giving them different antioxidant capacity and lower digestibility. Findings are beneficial for understanding interaction between starch and different phenols and their potential application.

Effects of alginate synergized with polyphenol compounds on the retrogradation properties of corn starch

This study aimed to investigate the impact of alginate (AG) on the retrogradation properties of corn starch (CS) in conjunction with three phenolic compounds, including naringin (NA), rutin (RT), and soy isoflavones (SI). The findings indicated that AG, NA, RT, and SI collectively resulted in a significant reduction in the hardness, retrogradation enthalpy, and relaxation time of CS gel. This effect was more pronounced when compared to NA, RT, and SI individually. The findings suggested that the elemental system comprising AG, phenolic compounds, and CS yielded enhanced water retention capacity and thermal stability. Moreover, a noticeable decrease in the short-range ordered structure and crystallinity was observed, indicating that AG and phenolic compounds effectively inhibited the retrogradation of CS; notably, the synergistic interaction between AG and SI resulted in the most favorable outcome. The results of this study provide new ideas for the design, development, and quality improvement of starch-based food.

Binary hydrogels constructed from lotus rhizome starch and different types of carrageenan for dysphagia management: Nonlinear rheological behaviors and structural characteristics

This study focused on binary hydrogels constructed from lotus rhizome starch (LRS) and three types of carrageenan (κ-C, ι-C, and λ-C). The enthalpy of LRS gelatinization was reduced by 32.1%-88.4% with the incorporation of carrageenan. Compared with ι-C and λ-C, the conformations of κ-C more facilitated the development of the binary hydrogel network structure. The ability of the LRS/carrageenan binary hydrogel to immobilize water was mainly related to the effect of different types of carrageenan on starch molecular ordering. LRS-based hydrogels were recognized as level 4 in the International Dysphagia Diet Standardization Initiative (IDDSI) framework. Nevertheless, the incorporation of carrageenan significantly reduced the ability of the LRS hydrogel to resist stress under large deformations, which might be favorable to oral processing and swallowing. This research provides preliminary evidence for relevant industries to use carrageenan to adjust LRS hydrogel properties and improve the quality of starch-based foods for dysphagia management.

Interactions between corn starch and lingonberry polyphenols and their effects on starch digestion and glucose transport

This study investigated the interaction mechanism between corn starch (CS) and lingonberry polyphenols (LBP) during starch gelatinization, focusing on their effects on starch structure and physicochemical properties. Moreover, it explored the effect of this interaction on starch digestion and glucose transport. The results indicated that LBP interacted non-covalently with CS during starch gelatinization, disrupted the short-range ordered structure of starch, decreased gelatinization enthalpy of starch, and formed a dense network structure. Furthermore, the incorporation of LBP remarkably reduced the digestibility of CS. In particular, the addition of 10 % LBP decreased the terminal digestibility (C∞) from 77.87 % to 60.43 % and increased the amount of resistant starch (RS) by 21.63 %. LBP was found to inhibit α-amylase and α-glucosidase in a mixed manner. Additionally, LBP inhibited glucose transport in Caco-2 cells following starch digestion. When 10 % LBP was added, there was a 34.17 % decrease in glucose transport compared with starch digestion without LBP. This study helps establish the foundation for the development of LBP-containing starch or starch-based healthy foods and provides new insights into the mechanism by which LBP lowers blood glucose.

Optimization of ultrasonic conditions for improving the characteristics of corn starch-glycyrrhiza polysaccharide composite to prepare enhanced quality lycopene inclusion complex

In this study, based on response surface optimization of ultrasound pre-treatment conditions for encapsulating lycopene, the corn starch-glycyrrhiza polysaccharide composite (US-CS-GP) was used to prepare a novel lycopene inclusion complex (US-CS-GP-Lyc). Ultrasound treatment (575 W, 25 kHz) at 35 °C for 25 min significantly enhanced the rheological and starch properties of US-CS-GP, facilitating the preparation of US-CS-GP-Lyc with an encapsulation efficiency of 76.12 ± 1.76 %. In addition, the crystalline structure, thermal properties, and microstructure of the obtained lycopene inclusion complex were significantly improved and showed excellent antioxidant activity and storage stability. The US-CS-GP-Lyc exhibited a V-type crystal structure, enhanced lycopene loading capacity, and reduced crystalline regions due to increased amorphous regions, as well as superior thermal properties, including a lower maximum thermal decomposition rate and a higher maximum decomposition temperature. Furthermore, its smooth surface with dense pores provides enhanced space and protection for lycopene loading. Moreover, the US-CS-GP-Lyc displayed the highest DPPH scavenging rate (92.20 %) and enhanced stability under light and prolonged storage. These findings indicate that ultrasonic pretreatment can boost electrostatic forces and hydrogen bonding between corn starch and glycyrrhiza polysaccharide, enhance composite properties, and improve lycopene encapsulation, which may provide a scientific basis for the application of ultrasound technology in the refined processing of starch-polysaccharides composite products.

Purple rice starch in wheat: Effect on retrogradation dependent on addition amount

While individual starch types may not possess the ideal gelatinization and retrogradation properties for specific applications, the amalgamation of multiple starch varieties might bestow desirable physicochemical properties upon resulting starch-based products. This study explored the impact of incorporating purple rice starch (PRS), as a novel starch variant (up to 15 % PRS), on the gelatinization and retrogradation (within 14 days) of regular wheat starch (WS). Rheological and texture assessments demonstrated that the introduction of PRS diminished the viscoelasticity and hardness of fresh WS paste. Additionally, in the case of retrograded WS pastes stored at 4 °C for 1-14 days, the incorporation of 10 % or 15 % PRS effectively retarded the reduction in transparency and significantly reduced hardness, retrogradation degree, the ratio of absorbance at 1047/1017 cm-1, and relative crystallinity. Notably, 10 % PRS results in a more pronounced effect. Conversely, 5 % PRS induced an opposing impact on retrograded WS post-storage. Moreover, scanning electron microscopy revealed that as the proportion of PRS increased, the microstructure of gelatinized WS-PRS closely resembled that of pure PRS. In conclusion, the diverse effects of varying PRS proportions on WS alter the texture and characteristics of starch-based foods, underscoring the potential of starch blending for improved applications.

Characterization and Antioxidant and Antibacterial Activities of Carboxymethylated Tamarind Seed Polysaccharide Composite Films Incorporated with ε-Polylysine and Their Application in Fresh-Cut Green Bell Pepper Preservation

Traditional petroleum-based food-packaging materials have poor permeability, limited active packaging properties, and difficulty in biodegradation, limiting their application. We developed a carboxymethylated tamarind seed polysaccharide composite film incorporated with ε-polylysine (CTPε) for better application in fresh-cut agricultural products. The CTPε films exhibit excellent water vapor barrier properties, but the mechanical properties are slightly reduced. Fourier transform infrared spectroscopy and X-ray diffraction spectra indicate the formation of hydrogen bonds between ε-PL and CTP, leading to their internal reorganization and dense network structure. With the increase of ε-PL concentration, composite films showed notable inhibition of postharvest pathogenic fungi and bacteria, a significant enhancement of 2,2'- azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical-scavenging activity, and gradual improvement of wettability performance. Cytotoxicity experiments confirmed the favorable biocompatibility when ε-PL was added at 0.3% (CTPε2). In fresh-cut bell pepper preservation experiments, the CTPε2 coating effectively delayed weight loss and malondialdehyde increase preserved the hardness, color, and nutrients of fresh-cut peppers and prolonged the shelf life of the fresh-cut peppers, as compared with the control group. Therefore, CTPε composite films are expected to be a valuable packaging material for extending the shelf life of freshly cut agricultural products.

Effect of soybean polysaccharide and soybean oil on gelatinization and retrogradation properties of corn starch

This investigation stems from the wide interest in mitigating starch retrogradation, which profoundly impacts the quality of starch-based food, garnering significant attention in the contemporary food industry. Our study delves into the intricate dynamics of soluble soybean polysaccharide (SSPS) and soybean oil (SO) when added individually or in combination to native corn starch (NCS), offering insights into the gelatinization and retrogradation phenomena. We observed that SSPS (0.5 %, w/w) hindered starch swelling, leading to an elevated gelatinization enthalpy change (∆H) value, while SO (0.5 %, w/w) increased ∆H due to its hydrophobicity. Adding SSPS and/or SO concurrently reduced the viscosity and storage modulus (G') of starch matrix. For the starch gel (8 %, w/v) after refrigeration, SSPS magnified water-holding capacity (WHC) and decreased hardness through hydrogen bonding with starch, while SO increased hardness with limited water retention. Crucially, the combination of SSPS and SO maximized WHC, minimized hardness, and significantly inhibited starch retrogradation. The specific ratio of SSPS to SO was found to significantly influence the starch properties, with a 1:1 ratio resulting in the most desirable quality for application in starch-based foods. This study offers insights for utilizing polysaccharides and lipids in starch-based food products to extend shelf life.

Incorporation of Lepidium perfoliatum seed gum into wheat starch affects its physicochemical, viscoelastic, pasting and freeze-thaw syneresis properties

This study aimed to investigate the influence of incorporating Lepidium perfoliatum seed gum (LPSG) into wheat starch (WS) at various mixing ratios on its FTIR, DSC, steady and dynamic rheological properties, pasting attributes, syneresis, and particle size distributions characteristics. The interaction between WS and LPSG was purely based on hydrogen-bonding. It was found that the onset (To) and peak (Tp) temperatures of the LPSG-rich mixtures increased by 10 % and 8 %, respectively, while the enthalpy (ΔH) decreased by 70 % compared to WS. A higher LPSG ratio led to a decrease in the frequency dependence of storage modulus (G'), as well as an increase in the pseudoplasticity of the mixtures. The in-shear structural recovery test showed that the rate of recovery (R, %) increased with an increasing LPSG ratio. The pasting results demonstrated that the 9/1 ratio had the highest final viscosity and the lowest relative breakdown. Applying 1 to 5 freeze-thaw cycles resulted in a 50 % to 70 % decrease in syneresis for the 9/1 mixing ratio in comparison to WS, respectively. The incorporation of LPSG into WS resulted in higher static and dynamic magnitudes of yield stress, as well as an increase in particle size when compared to WS.

Fabrication of multi-functional biodegradable liquid mulch utilizing xyloglucan derived from tamarind waste for agricultural application

Biodegradable liquid mulch is considered a promising alternative to plastic mulch for sustainable agriculture. This work proposed a xyloglucan-based liquid mulch with multi-function using a combination of chemical modification and blending methods. The esterification product of tamarind xyloglucan (TXG) from forestry wastes was synthesized with benzoic anhydride (BA). The effect of esterification modification was investigated, and BA-TXG was utilized as a film-forming and sand-fixation agent. The rheological properties, thermal stability, and hydrophobicity were improved following esterification. Additionally, waterborne polyurethane and urea were incorporated into the mulch to enhance its mechanical strength (23.28 MPa, 80.71 %), and homogeneity, as well as improve its nutritive properties. The xyloglucan-based liquid mulch has excellent UV protection, a high haze value (approximately 90 %), and retains water at a rate of 80.45 %. SEM and immersion experiment showed the effect of xyloglucan-based liquid mulch on sustainable sand-fixation. Moreover, the liquid mulch treatment demonstrated an impressive germination rate of 83.8 % and degradation rate of 51.59 % (60 days). The modified polysaccharide film increases stability and slows down the degradation rate. Tamarind xyloglucan-based liquid mulch exhibits powerful and diverse optical properties as well as sand fixation functions, indicating their great potential in sustainable agriculture as an alternative to plastic mulch.

Effects of zucchini polysaccharide on pasting, rheology, structural properties and in vitro digestibility of potato starch

Zucchini polysaccharide (ZP) has a unique molecular structure and a variety of biological activities. This study aimed to evaluate the effects of ZP (1, 2, 3, 4 and 5 %, w/w) on the properties of potato starch (PS), including pasting, rheological, thermodynamic, freeze-thaw stability, micro-structure, and in vitro digestibility of the ZP-PS binary system. The results showed that the appearance of ZP significantly reduced the peak, breakdown, final and setback viscosity and prolonged the pasting temperature of PS, whereas increased the trough viscosity. The tests of rheological showed that ZP had a damaging effect on PS gels. Meanwhile, the results of thermodynamic and Fourier transform infrared exhibited that the presence of ZP significantly retarded the retrogradation of PS, especially at a higher levels. The observation of the microstructure exhibited that ZP significantly altered the microscopic network structure of the PS gels, and ZP reduced the formation of the gel structure. Besides, ZP postponed the retrogradation process of PS gels. Moreover, ZP weakened the freeze-thaw stability of the PS gel. Furthermore, ZP also can decrease the digestibility and estimated glycemic index (eGI) value of PS from 86.04 % and 70.89 to 77.67 % and 65.22, respectively. Simultaneously, the addition of ZP reduced the rapidly digestible starch content (from 25.09 % to 16.59 %) and increased the slowly digestible starch (from 24.99 % to 26.77 %) and resistant starch content (from 49.92 % to 56.64 %). These results have certain guiding significance for the application of ZP in starch functional food.

Bulk industrial production of sustainable cellulosic printing fabric using agricultural waste to reduce the impact of climate change

In this research paper, a novel process was developed for reactive printing of cotton fabric, with the objective of producing a high-quality printed fabric that is sustainable, eco-friendly, and low-cost which will ultimately reduce the impact of climate change. The study incorporated substituted tamarind polysaccharide (STP) obtained from agricultural waste, trichloro-ethanoic acid (TCEA), and polyethylene glycol (PEG-400) in the reactive printing paste. Tamarind starch was extracted from the seeds having 72 % yield, and substitution was performed to use it as a thickener in the printing paste. The conventional printing system was formulated with sodium alginate, urea, and sodium bicarbonate at dose levels of 2 %, 15 %, and 2.5 %, respectively, while the modified recipe was formulated with STP and TCEA at 5 % and 3 % dose levels, respectively along with varying doses of PEG-400 (0 %, 1 %, and 2 %) in novel prints. Various factors such as shade comparison, penetration, staining on the white ground, washing, rubbing, light and perspiration fastness, sharpness of edges, and fabric hardness were evaluated for all the recipes. The study demonstrated that the optimal outcomes were obtained with a 2 % PEG-400 dose level. This study represents a significant contribution to sustainable textile production, as tamarind agriculture waste was used as a raw material, which is an environmentally friendly alternative of sodium alginate that reduces the wastewater load. Additionally, PEG-400 was utilized as a nitrogen-free solubilizing moisture management substitution of urea for printing, while TCEA dissociated at high temperature to make alkaline pH during curing of the printed fabric to replace sodium bicarbonate. This research is a novel contribution to the printing industry, as these three constituents have not been previously used together other than this research group, in the history of reactive printing.

The interaction and physicochemical properties of the starch-polyphenol complex: Polymeric proanthocyanidins and maize starch with different amylose/amylopectin ratios

This study investigated the impact of polymeric proanthocyanidins (PPC) on the physicochemical characteristics of maize starch with varying amylose content, and their potential interaction mechanism. PPC with a lower content (1 %) reduced the viscoelasticity of the high amylose maize starch (HAM) system, inhibited amylose rearrangement, and enhanced its fluidity. However, excessive PPC restrained the interaction between PPC and amylose. In contrast to HAM, PPC improved the gelation ability of waxy maize starch (WAM) as PPC concentration was raised. PPC suppressed the recrystallization of starch during storage, and PPC had a superior inhibition influence on the retrogradation of WAM in comparison to HAM. This indicated that amylopectin was more likely to interact with PPC than amylose. Hydrogen bonds were the main driving force between PPC and starch chains, which was clarified by Fourier transform-infrared, nuclear magnetic resonance, X-ray diffraction, iodine bonding reaction, and dynamic light scattering data. Additionally, the mechanism of interaction between PPC and the two starch components may be similar, and variance in physicochemical attributes can be primarily credited to the percentage of amylose to amylopectin in starch.

Antitumor Activity of Carboxymethyl Pachymaran with Different Molecular Weights Based on Immunomodulatory and Gut Microbiota

Carboxymethyl pachymaran (CMP) was treated via high-temperature and cellulase hydrolysis to obtain HTCMP, HTEC-24, and HTEC-48. The chemical structure and in vivo antitumor activities of the four types of CMPs were investigated. Compared with CMP (787.9 kDa), the molecular weights of HTCMP, HTEC-24, and HTEC-48 were decreased to 429.8, 129.9, and 68.6 kDa, respectively. The viscosities and particle sizes of the CMPs could also decrease with the decline in the molecular weights. All the CMPs showed antitumor abilities, but HTEC-24 exhibited the best activity. In the animal study, when curing the spleen and thymus, CMPs displayed immunomodulatory effects by increasing the secretion of IFN-γ and IL2 in mice. The CMPs also exerted an antitumor ability by regulating the gut microbiota in tumor-bearing mice. Our results established a foundation to develop an antitumor drug with CMP.

Insights into the modification of physicochemical properties and digestibility of pea starch gels with barley β-glucan

The influences of barley β-glucan (BBG) on the physicochemical properties and in vitro digestibility of pea starch were investigated. BBG was found to decrease pasting viscosity in a concentration dependent manner and inhibited the aggregation of pea starch. After the presence of BBG, the gelatinization enthalpy of pea starch was decreased (from 7.83 ± 0.03 to 5.55 ± 0.22 J/g), whereas the gelatinization temperature was enhanced (from 62.64 ± 0.01 to 64.52 ± 0.14°C) according to the differential scanning calorimeter results. In addition, BBG inhibited the swelling of pea starch and amylose leaching. When amylose leached out from pea starch to form a BBG-amylose barrier, starch gelatinization was inhibited. The starch gels exhibited weak gels and shear thinning behaviors by rheological tests results. The interaction between BBG and amylose led to lower viscoelasticity and texture parameters in pea starch gels. The structure analysis results unveiled that the force between BBG and amylose was mainly hydrogen bonds. Pea starch hydrolysis was inhibited when BBG was present in the system, which was connected with the restricted starch gelatinization. These results obtained in the study would supply insights into incorporating BBG into various food systems.

Effects of Porphyra haitanensis polysaccharides on gelatinization and gelatinization kinetics of starches with different crystal types

The effects of Porphyra haitanensis polysaccharide (PHP) on the gelatinization and gelatinization kinetics of corn starch (CS), potato starch (PS) and lotus seed starch (LS) were studied. The gelatinization, rheological and thermal enthalpy properties of the samples were measured by a rapid viscosity analyzer (RVA), a rheometer, and a differential scanning calorimeter (DSC), respectively. And the kinetic equations were further established. RVA confirmed that the addition of 0.4 %, 0.8 % and 1.2 % PHP elevated the gelatinization viscosity of CS and LS but decreased that of the PS, and also elevated the thermal balance of CS, PS, and LS, especially PS (The breakdown viscosity was decreased to 363.00 ± 6.08, 370.00 ± 1.15, and 362.00 ± 0.58, respectively). And the rheometer indicated that the addition of 0.4 %, 0.8 % and 1.2 % PHP improved the apparent viscosity of CS, PS and LS, especially PS (The consistency coefficient was increased to 18.26 ± 0.02, 21.71 ± 0.04, and 23.26 ± 0.01, respectively). Eventually, DSC displayed that the addition of 0.4 %, 0.8 % and 1.2 % PHP extended the gelatinization temperature and enthalpy of CS, PS, and LS, especially PS. Among them, the gelatinization temperature (63.40 ± 0.03, 70.26 ± 0.02 and 74.61 ± 0.01, respectively) and the gelatinization enthalpy (1.55 ± 0.01) of PS increased the most with 1.2 % PHP. Moreover, gelatinization kinetics displayed that the addition of 0.4 %, 0.8 % and 1.2 % PHP decreased the rate constants of CS, PS, and LS and accelerated the activation energies of CS (666.37 ± 4.23, 623.89 ± 4.21 and 558.39 ± 2.35, respectively) and PS (752.53 ± 4.13, 699.61 ± 3.78 and 662.15 ± 4.52, respectively) while reducing that of the LS (938.87 ± 3.38, 669.98 ± 4.61 and 491.48 ± 4.29, respectively). Therefore, the addition of PHP at all concentrations inhibited the gelatinization procedure of CS and PS but promoted that of the LS. This study provided a theoretical basis for the creation of new products based on PHP and starch.

Impact of tamarind seed gum on the viscosity behavior, thermal properties, and extrusion characteristics of native corn starch

Tamarind seed gum (TSG) is a cold-swelling hydrocolloid with remarkable processing stability and starch synergy. Its use in direct expanded extruded foods has not been documented. The thermal and pasting viscosity properties of six TSG (0%, 0.5%, 1.0%, 2.5%, 5.0%, and 7.5% TSG) and native corn starch blends were characterized by differential scanning calorimetry and ViscoQuick, respectively. These same blends were extruded using a corotating twin-screw extruder at four screw speeds (SSs) (150, 300, 450, and 600 rpm). System back pressure, motor torque, and specific mechanical energy (SME) were measured. Extrudate quality metrics, such as expansion ratio (ER), water absorption index (WAI), and water solubility index (WSI), were also measured. The pasting viscosities indicated that TSG inclusion increases viscosity but also makes the starch-gum paste more susceptible to permanent shear degradation. The thermal analysis indicated that TSG inclusion narrowed the melting endotherms and lowered the energy required for melting (p < 0.05) at higher inclusion levels. Extruder back pressure, motor torque, and SME decreased with increasing TSG levels (p < 0.05) as the TSG effectively lowered the melt viscosity at high usage rates. The ER reached a maximum of 3.73 with a 2.5% TSG level extruded at 150 rpm (p < 0.05). The WAI of extrudates increased with TSG inclusion rate at equivalent SSs, whereas WSI behaved oppositely (p < 0.05). Small inclusions of TSG can improve the expansion properties of starch, whereas larger inclusions result in a lubrication effect that mitigates the shear-induced depolymerization of starch. PRACTICAL APPLICATION: The impact of cold-water soluble hydrocolloids, including tamarind seed gum, on the extrusion process, is poorly understood. From this work, tamarind seed gum effectively modifies the viscoelastic and thermal characteristics of corn starch in a way that enhances the direct expansion characteristics of the starch during extrusion processing. The effect is more beneficial at lower gum inclusion levels as higher levels result in reduced capabilities to translate shear from the extruder into useful transformations of the starch polymers during processing. Small amounts of tamarind seed gum could be used to improve the quality of extruded starch puff snacks.

High-amylose maize starch: Structure, properties, modifications and industrial applications

High-amylose maize refers to a special type of maize cultivar with a 50 %-90 % amylose content of the total starch. High-amylose maize starch (HAMS) is of interest because it possesses unique functionalities and provides many health benefits for humans. Therefore, many high-amylose maize varieties have been developed via mutation or transgenic breeding approaches. From the literature reviewed, the fine structure of HAMS is different from the waxy and normal corn starches, influencing its gelatinization, retrogradation, solubility, swelling power, freeze-thaw stability, transparency, pasting and rheological properties, and even in vitro digestion. HAMS has undergone physical, chemical, and enzymatical modifications to enhance its characteristics and thereby broaden its possible uses. HAMS has also been used for the benefit of increasing resistant starch levels in food products. This review summarizes the recent developments in our understanding of the extraction and chemical composition, structure, physicochemical properties, digestibility, modifications, and industrial applications of HAMS.

Insights on Some Polysaccharide Gel Type Materials and Their Structural Peculiarities

Global resources have to be used in responsible ways to ensure the world's future need for advanced materials. Ecologically friendly functional materials based on biopolymers can be successfully obtained from renewable resources, and the most prominent example is cellulose, the well-known most abundant polysaccharide which is usually isolated from highly available biomass (wood and wooden waste, annual plants, cotton, etc.). Many other polysaccharides originating from various natural resources (plants, insects, algae, bacteria) proved to be valuable and versatile starting biopolymers for a wide array of materials with tunable properties, able to respond to different societal demands. Polysaccharides properties vary depending on various factors (origin, harvesting, storage and transportation, strategy of further modification), but they can be processed into materials with high added value, as in the case of gels. Modern approaches have been employed to prepare (e.g., the use of ionic liquids as "green solvents") and characterize (NMR and FTIR spectroscopy, X ray diffraction spectrometry, DSC, electronic and atomic force microscopy, optical rotation, circular dichroism, rheological investigations, computer modelling and optimization) polysaccharide gels. In the present paper, some of the most widely used polysaccharide gels will be briefly reviewed with emphasis on their structural peculiarities under various conditions.

The Synthesis, Characterization, and Protein-Release Properties of Hydrogels Composed of Chitosan-Zingiber offcinale Polysaccharide

Most proteins given orally have low bioavailability and are easily eliminated by rapid metabolism in vivo. In order to immobilize the drug at the site of administration and delay its release, a natural, gentle release system was designed. In this study, a heteropolysaccharide (ZOP) was isolated from Zingiber officinale using an ultrasonic assisted extraction method. ZOP Ara = 1.97: 1.15: 94.33: 1.48: 1.07. The ZOP/Chitosan (CS) composite hydrogel was synthesized using epichlorohydrin (ECH) as a cross-linking agent. The structure, morphology, and water-holding capacity of the composite hydrogel were characterized. The data showed that the addition of ZOP improved the hardness and water-holding capacity of the material. A swelling ratio test showed that the prepared hydrogel was sensitive to pH and ionic strength. In addition, the degradation rate of the hydrogel in a phosphate-buffered saline (PBS) solution with a pH value of 1.2 was higher than that in PBS with pH value of 7.4. Similarly, the release kinetics of Bovine serum albumin (BSA) showed higher release in an acidic system by the hydrogel composed of ZOP/CS. The hydrogel prepared by this study provided a good microenvironment for protein delivery. In summary, this composite polysaccharide hydrogel is a promising protein-drug-delivery material.

Interaction between Gelatin and Mulberry Leaf Polysaccharides in Miscible System: Physicochemical Characteristics and Rheological Behavior

In this study, the miscible system was formed by mixing gelatin (G) with mulberry leaf polysaccharides (MLPs) continuously extracted with a hot buffer (HBSS), a chelating agent (CHSS), a dilute alkali (DASS), and a concentrated alkali (CASS), and the zeta potential, turbidity, particle size, distribution, and rheological properties of the miscible systems were evaluated. Under acidic conditions, the miscible systems of four polysaccharides and gelatin were in a clear state; under alkaline conditions, G-HBSS and G-CHSS were clarified, and G-DASS and G-CASS changed from clarification to turbidity. The zeta potential changed from positive to negative with the increase in pH. When the pH was at 7, it increased with the increase in polysaccharide concentration but was still negative. The four miscible systems all showed polydispersity. The particle sizes of G-HBSS and G-CHSS decreased with the increase in pH, while the particle sizes of G-DASS and G-CASS were increased. The four miscible systems showed “shear thinning” behavior, and the addition of gelatin reduced the apparent viscosity of the four polysaccharide solutions. G-CHSS was highly stable, and G-CASS was more suitable as a stabilizer in the freezing process.

Modification of starch by polysaccharides in pasting, rheology, texture and in vitro digestion: A review

Starch is a copolymer with unique physicochemical characteristics, is known for its low cost, easy degradability, renewable and easy availability. However, natural starches have some undesirable properties such as poor solubility, poor functional properties, lower resistant starch content with reduced retrogradation, and poor stability under various temperatures, pH, which limit their application in food. Different modification methods are used to improve its performance and expand its application. Numerous studies have been conducted to investigate why the addition of small amounts of polysaccharides affects the properties of starch pastes and gels. The application of polysaccharide-modified starch can be seen in the pasting, rheology, texture and in vitro digestive properties of starch gels. The main influencing factors include different starches, different specific polysaccharides, and different methods of preparation of composite pastes and gels. This paper reviews the changes in the properties of starch in terms of pasting, rheology, texture and in vitro digestion after modification with polysaccharides and the mechanism of polysaccharide action on starch.

Separation of principal component dihydromyricetin from Ampelopsis grossedentata by high-speed counter-current chromatography and its interaction with corn starch

Ampelopsis grossedentata (AG) is an industrial crop in the grape family, which has been used as a dual-purpose plant for medicine and tea with high medicinal values. However, little is reported on the separation technology of active components from AG and processing technology of AG products. High-speed counter-current chromatography (HSCCC) was applied to separate the principal component dihydromyricetin (DMY) from AG. DMY is added to starch-based products to improve food quality. The interaction between corn starch (CS) and DMY was investigated to predict and control the structure and function of starch-based foods. Results show that DMY with 97.13% purity was successfully obtained by HSCCC using a solvent system composed of light petroleum-ethyl acetate-methanol-water-trichloroacetic acid (1:3:1:3:0.01, v/v/v/v/v). Fourier-transform infrared spectroscopy (FT-IR) exhibits that the interactions between CS and DMY included hydrogen bond and noncovalent bond. X-ray diffraction (XRD) shows that DMY could increase the relative crystallinity of CS. Low-field nuclear magnetic resonance results (LF-NMR) imply that DMY decreased the spin relaxation time (T₂ ) and inhibited the mobility of free water. Atomic force microscopy (AFM) results suggest that DMY changed the surface morphology of CS through hydrogen bond interaction. Moreover, the results of confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) indicate that DMY could enlarge the pores and change the microstructure of CS-DMY complexes. The findings promote the development of industrial CS-based products and utilization of corn crop.

Separation of gallic acid from Cornus officinalis and its interactions with corn starch

D101 macroporous resin combined with high speed counter-current chromatography (D101 MR-HSCCC) was used to separate gallic acid (GA) from Cornus officinalis, and GA was added to starch-based products to improve food quality. The interaction and action mechanism of corn starch (CS) with GA were investigated for prediction and thereby controlling the structure and functions of starch-based foods. Results show that GA with 98.72% purity was successfully obtained using the D101 MR-HSCCC technique. HSCCC solvent system was composed of n-hexane-ethyl acetate-methanol-water (1:5:1:5, v/v/v/v). GA inhibited CS dissolution and improved CS swelling. Based on the particle size distribution, GA could enlarge the size of CS-GA complexes. FT-IR spectra exhibit that the interactions between CS and GA may comprise the intermolecular hydrogen bond and non-covalent bond. The results of XRD, LF-NMR and AFM show that the presence of GA could increase the relative crystallinity of CS, decrease the spin relaxation time (T₂)_, and change the surface morphology of CS via the modification of hydrogen bonds distribution. Finally, SEM analysis indicates that GA could change the microstructure of CS-GA complexes. These findings facilitate the development of CS-based products and utilization of CS.

Effects and mechanism of sucrose on retrogradation, freeze-thaw stability, and texture of corn starch-tamarind seed polysaccharide complexes

In this work, we investigated the effects of sucrose (0%-30%, w/w) on the pasting properties, retrogradation, freeze-thaw stability, texture, and the possible interaction with corn starch-tamarind seed polysaccharide (CS-TSP) mixtures. Sucrose increased the gelatinization temperature (from 76.4 ± 0.1 to 87.6 ± 0.0°C), peak viscosity (from 3358.0 ± 1.4 to 7732.5 ± 44.5 cP), and final viscosity (from 3514.0 ± 31.1 to 7724.5 ± 142.1 cP) of CS-TSP mixtures. Further, sucrose limited the increase in the storage modulus of the mixture pastes, transfer of bound water to free water, and water syneresis during the freeze-thaw process. Additionally, sucrose resulted in a more complete gel structure with stronger resistance. Scanning electron microscope and fluorescence labeling analysis showed that the presence of sucrose helped in tight entanglement or cross-link between amylose or between amylose and TSP. Thus, these results in this study could help to improve physicochemical properties of starch-based products, such as glue pudding and other starch desserts.

Effects of Inca peanut seed albumin fraction on rheological, thermal and microstructural properties of native corn starch

In this work, the effect of Inca peanut seed albumin fraction (IPA) on the rheological, thermal and microstructural properties of native corn starch (NCS) was firstly studied. Compared to the NCS, IPA addition could obviously decrease the transparency of NCS, and the transparency of NCS and NCS-IPA suspensions decreased during the storage time. The textural paraments of NCS pastes with or without IPA reached to the maximum at a concentration of 5%. Steady shear rheological tests showed that all systems were non-Newtonian fluid, and the consistency coefficient (K) values reached to the maximum at 5% IPA concentration. The storage and loss modulus values of NCS-IPA pastes were higher than those of NCS pastes, and curves of loss angle (tan δ) indicated that all pastes were typical weak gel. With the increasing addition of IPA, DSC analysis showed that the thermal properties (To, Tp and Tc) of NCS were significantly changed, whereas, there was no distinct difference in the enthalpy. Microscopy illustrated that there were some wrinkle shrinkage and severe folds on the NCS-IPA granules. Fourier-transform infrared (FT-IR) spectroscopy showed that the hydrogen bonding was primarily interaction forces between IPA and NCS molecules.

Effect of inulin on pasting, thermal, rheological properties and in vitro digestibility of pea starch gel

The influence of inulin (IN) on pasting, thermal, rheological properties, and in vitro digestibility of pea starch gel was investigated. Results showed that as the concentration of IN in PS increased, the pasting temperature of PS gradually increased, while the value of peak viscosity, breakdown, and setback decreased. Rheological test suggested that all PS-IN gels were typical non-Newtonian fluids and exhibited a solid-like behavior. With the increased concentration of IN, hardness, chewiness, and gumminess of PS-IN gels significantly declined, in which the minimum value was at addition level of 20%. The presence of IN increased the gelatinization temperatures of PS-IN gels, while decreased the gelatinization enthalpy. Fourier-transform infrared spectroscopy (FT-IR) results indicated that no covalent bonding but intermolecular hydrogen bonding occurred between PS and IN. No influence of IN on the diffraction peak of PS after pasting was confirmed by X-ray diffraction analysis. In addition, IN decreased the content of rapidly and slowly digestible starch of PS, while increasing the content of resistant starch. These results will expand the application range of PS, and also provide a theoretical basis for the development of inulin-starch based products.

Gelatinization, Retrogradation and Gel Properties of Wheat Starch-Wheat Bran Arabinoxylan Complexes

Gelatinization, retrogradation and gel properties of wheat starch–wheat bran arabinoxylan (WS–WBAX) complexes have been evaluated. The results of rapid viscosity analyzer (RVA), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) confirmed that WBAX samples with larger Mw and branching degree (HWBAX) significantly impeded gelatinization process of starch by effectively reducing the amount of water available for starch gelatinization. DSC analysis showed that both molecular characteristics and additive amount of WBAX samples have an effect on the long-term retrogradation behavior of starch. For the rheological studies of WS–WBAX mixed gels, the elastic moduli (G’) and shear viscosity of WS–WBAX mixed gels increased with the increase in additive amount of WBAX. WS–HWBAX mixed gels exhibited the lower G’ compared with starch gels containing WBAX with lower Mw and branching degree (LWBAX) at the same amount. The scanning electron micrographs (SEM) revealed that the microstructures of WS–WBAX mixed gels were mainly affected by the amount of WBAX, but hardly by the molecular characteristics of WBAX. Texture profile analysis (TPA) showed that the cohesiveness of fresh WS–WBAX mixed gels became larger with an increase in the WBAX addition amount. The hardness of WS–WBAX mixed gels tended to increase over the 14-day storage.

Effects of Pectin on the Physicochemical Properties and Freeze-Thaw Stability of Waxy Rice Starch

In this study, the effects of the addition of pectin (PEC) on the physicochemical properties and freeze-thaw stability of waxy rice starch (WRS) were investigated. As PEC content increased, the pasting viscosity and pasting temperature of WRS significantly increased (p < 0.05), whereas its breakdown value and setback value decreased. Differential scanning calorimetry showed that the addition of PEC increased the gelatinization temperature of WRS, but decreased its gelatinization enthalpy. Rheological measurements indicated that the addition of PEC did not change the shear-thinning behavior of WRS-PEC blends, and the storage modulus and loss modulus were positively correlated with PEC content. Moreover, the textural parameter of WRS decreased with the increase in PEC content. Furthermore, the addition of PEC decreased the transmittance of starch paste, but enhanced the freeze-thaw stability of WRS to some extent. These results may contribute to the development of WRS-based food products.

Effect of dandelion root polysaccharide on the pasting, gelatinization, rheology, structural properties and in vitro digestibility of corn starch

The influence of dandelion root polysaccharide (DRP) on the gelatinization properties and in vitro digestibility of corn starch was investigated. Pasting behaviors indicated that the addition of DRP led to an increase of the pasting temperature and a decrease of viscosity. Compared to native corn starch, the swelling power, solubility and content of amylose leaching were reduced as the DRP addition increased. Scanning electron microscopy (SEM) analysis showed that DRP was easily dispersed in the starchy matrix, and a more uniform structure was observed in corn starch/DRP pastes. Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) analyses confirmed that the crystal shape of the corn starch gels was not changed and no new groups were produced with increasing DRP concentration. Moreover, DRP could improve the fluidity of the gelatinized corn starch and reduce its digestibility. These findings provided fundamental information about DRP's application in the whole processing of corn starch.

Structural characteristics of tamarind seed polysaccharides treated by high-pressure homogenization and their effects on physicochemical properties of corn starch

In this work, structural characteristics of TSPs treated by high-pressure homogenization (HPH) and their effects on physicochemical properties of corn starch were analyzed. HPH induced monosaccharides change, Gal/Glc ratio decrease from 0.32 to 0.25, and molecular weight (M_w) decrease from 10.55 to 4.47 × 10⁵ Da through damaging glycosidic linkages in the backbone and side-chain of TSPs. Furthermore, 90 MPa homogenized TSP (higher Gal removal) showed inhibitory effects on starch paste retrogradation, and TSPs with a lower M_w (homogenized at 60 and 90 MPa) could limit water precipitation during the long-term storage. Moreover, M_w and Gal/Glc ratio were the major factors for the determined effects of TSPs on physicochemical properties of corn starch. The results could provide new insights into the relationship between TSP structure and their effects on the physicochemical properties of starch.

Optimization, characterization and evaluation of papaya polysaccharide-corn starch film for fresh cut apples

In this study, we prepared corn starch (CS) and papaya polysaccharide (PPs) films using the solution casting technique. A Box-Behnken experimental design was used to determine the effect of ethanol concentration, extraction duration, and material concentration during PPs extraction. The resulting films were characterized in terms of structural changes, physical, optical, mechanical, Fourier-transform infrared (FTIR) spectroscopy, and thermal properties. The results show that PPs-CS composite films have good antioxidant and moisturizing properties and general antibacterial performance. These results revealed that after adding PPs, the films exhibited a significant increase in swelling and tensile strength, while depicted a reduction in thickness, transparency, and solubility. SEM images revealed that PPs and CS are highly compatible; moreover, FTIR spectroscopy showed that intermolecular hydrogen bonding existed between CS and PPs, forming a compact film structure. Finally, the incorporation of PPs and CS influenced the shelf-life of fresh cut apples, with the edible film incorporated with PPs positively improving sensory acceptance of combined materials.

An ultrasonic-extracted arabinoglucan from Tamarindus indica L. pulp: A study on molecular and structural characterizations

In this study, an ultrasonic-extracted polysaccharide (nCPTP-55) was obtained with the highest yield (61.08%, w/w) from tamarind pulp, which consisted chiefly of total sugar (85.98%, w/w) with few protein (2.10%, w/w). Monosaccharide analysis showed nCPTP-55 was mainly composed of arabinose (39.19 mol%) and glucose (50.48 mol%) with negligible GlcA (2.05 mol%), indicating the neutral nature of nCPTP-55, which was further elucidated structurally via GC-MS and NMR, i.e., an arabinoglucan composed of →3)-β-D-Glcp-(1→ backbone with only T-α-L-Araf-(1→ branched at O-4 (27.82%) and O-6 (39.99%), resulting in relatively high A/G ratio (0.68-0.70). Based on MM2 minimized energy, the 3D schematic structures of nCPTP-55 could be considered as structural basis for its conformational behavior, which was preliminarily estimated via HPSEC-MALLS as between compact sphere and loosely hyper-branched chain (ρ = 0.84). Therefore, the relationship between molecular structure and conformational behavior was basically established for nCPTP-55, which was in a bid to have a better knowledge of its structure-property and structure-bioactivity relationships potentially required for more applications in food, cosmetic and pharmaceutical fields.