Pasting, rheological properties and gelatinization kinetics of tapioca starch with sucrose or glucose

Rheological and tribological properties of native potato starch agglomerated by fluidized bed granulator

We explored the rheological and tribological properties of potato starch agglomerated with a sugar binder (maltodextrin or lactose) at various concentrations by using a fluidized bed granulator. The magnitudes of consistency index and apparent viscosity of agglomerated potato starch (APS) decreased as the binder concentration was increased. Moreover, APS with a sugar binder showed lower viscoelastic moduli and higher tan δ values compared to APS with water as the binder (the control). The gel strength of all agglomerates decreased as the sugar concentration was increased. All samples showed anti-thixotropic behavior, and especially, APS with 20 % lactose showed a small anti-thixotropic area. Utilizing the Arrhenius equation clearly elucidated the effect of temperature on the apparent viscosity of all the samples. Although the maltodextrin concentration had little influence on the activation energy of APS, it increased as the lactose concentration was increased. APS samples with a sugar binder showed greater friction coefficient values compared to the control, with maltodextrin having a significant impact. The findings indicate that the rheological and tribological properties of APS rely on the type and concentration of sugar binder.

Effect of different sweeteners on the thermal, rheological, and water mobility properties of soft wheat flour and their application to cookies as an alternative to sugar

The effects of different sweeteners on the physicochemical properties of soft wheat flour were investigated mainly in terms of thermal, rheological, and water mobility features, and their feasibilities as an alternative to sugar were evaluated in the cookie system. Kestose significantly reduced the solvent retention capacity of wheat flour, followed by sucrose, fructose, and allulose. Thermal analysis showed that the sucrose and kestose distinctly led to an increase in the gelatinization temperature of wheat flour, which was explained by lower T2 relaxation times. In addition, the pasting viscosities and thermo-mechanical properties of wheat flour containing kestose became lower compared to allulose, and these differences were morphologically confirmed by the real-time microscopic measurements during heating. Furthermore, when the sweeteners were incorporated into the cookie formulations, kestose played a positive role as a sugar replacer in the cookie system by presenting a comparable spread factor, texture, and color to cookies with sucrose.

Tremella Polysaccharide Has Potential to Retard Wheat Starch Gel System Retrogradation and Mechanism Research

This study investigated the effects of adding different concentrations of TP (tremella polysaccharide) on the water distribution, rheological, thermal, microstructure, and retrogradation properties of WS (wheat starch) gels. The results showed that the starch aging increased during storage, and the addition of TP reduced the rate of change of the elastic modulus of the starch gel and delayed the short-term aging of WS. In the same storage period, the hardness value of the gel decreased and the texture became softer with the increase in the mass fraction of TP. TP increased the T0 (starting temperature) of the system and decreased the enthalpy of retrogradation (ΔHr). No new groups were formed after the retrogradation of the compound system, the hydrogen bonding force increased with the increase in polysaccharide, and the relative crystallinity and the degree of ordering of the system decreased. The addition of TP increased the content of bound water and immobile water, decreased the content of free water, and increased the gel water-holding capacity, indicating that it could effectively inhibit the long-term retrogradation of WS. The findings provide new theoretical insights for the production of starch-based foods.

Effects of Sucrose Replacement by Polyols on the Dough-Biscuit Transition: Understanding by Model Systems

This study investigated the impacts of the complete substitution of sucrose by maltitol and/or sorbitol on the dough-crumb transition in biscuits. To this end, the phenomena of starch gelatinization/melting were studied at different moisture contents, both in the biscuit dough and model systems, by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and by environmental scanning electron microscopy (ESEM). Observation of doughs in ESEM revealed sorbitol had a structure very different from sucrose and maltitol crystals. After forming the dough pieces, it could be seen that at least some sugar and maltitol crystals were still present while sorbitol flakes were solubilized. At a limiting real water content (~20% dry basis), adding sweeteners to the mixture increased the gelatinization temperature, more markedly for sucrose and maltitol, as well as increasing the enthalpy. These results were confirmed by the model systems analyses. The calorimetric study with mixing batch cells revealed that sorbitol dissolved completely while maltitol and sucrose competed with the flour constituents to capture water. The proportion of water available for the sorption of the starch grain and its gelatinization was therefore different according to the affinity of the sweetener for water, and might influence the degree and temperature of starch gelatinization/melting.

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 Citrus Peel Hydrolysates on Retrogradation of Wheat Starch

Retrogradation is the principal cause for bread staling and, therefore, it has attracted a lot of interest from the food industry. In this study, the inhibitory effect of citrus peel hydrolysates (CPH) on retrogradation of wheat starch (WS) in the presence of sucrose was investigated. The pasting properties showed that further addition of CPH caused a lower setback value than the addition of sucrose alone. Hardness of the gel, retrograded at 4 °C for five days, showed a similar tendency, which was reduced more in CPH addition than WS itself or sucrose addition alone. The low retrogradation enthalpy of the CPH including starch gel also indicated the positive effect of CPH on retarding retrogradation. These results suggested that incorporation of CPH in starch-based foods would be effective for inhibiting retrogradation, preventing the deterioration of the quality of food products.

Physicochemical and Structural Characterization of Potato Starch with Different Degrees of Gelatinization

Starch gelatinization has been widely studied previously, but there is still a lack of systematical research on the relationship between the degree of starch gelatinization (DSG) and its physicochemical and structural properties. In this study, potato starch samples with DSG ranging from 39.41% to 90.56% were obtained by hydrothermal treatment. The thermal, rheological, and structural properties, as well as the water-binding capacity of samples were investigated. A starch solution with a DSG of 39.41% was partially sedimented at room temperature, while starch with a DSG of 56.11% can form a stable paste with a fine shear-thinning property, as well as samples with a DSG larger than 56.11%. The endothermic enthalpy, gelatinization range, and short-range ordered structure of starch were negatively correlated with DSG, whereas onset gelatinization temperature, apparent viscosity, and water-binding capacity were positively correlated. The viscoelasticity of starch gels was negatively correlated with the DSG after full gelatinization (DSG > 39.41%). Starch granules gradually lose their typical shape and less birefringence can be observed with increasing DSG. Hydrothermal treatment has a more significant effect on the amount of exposed hydroxyl groups than the ordered and amorphous structures of partially gelatinized starch. This study built linear correlations between starch physicochemical properties and the DSG and provided comprehensive insight into the characteristics of partially gelatinized potato starch.

A kinetics-based decomposition approach to reveal the nature of starch asymmetric gelatinization thermograms at non-isothermal conditions

Starch gelatinization under non-isothermal conditions with limited moisture content is a common industrial process involved in the processing of many starchy foods, while the nature of its asymmetric differential scanning calorimetry thermograms is still undefinable. This study for the first time developed a kinetics-based mathematical model, which could yield a parameterization of gelatinization thermograms that are essentially the same as experimental ones. Even more, the model is capable of decomposing gelatinization thermograms into kinetics-based sub-patterns, and revealing hidden features. By applying this newly developed methodology to nine starches with different plant origins and correlated with their lamellar structures, the results indicated that distinctly arranged groups (sub-components) of semi-crystalline lamellae with different thermal stabilities are existed in the native starch granules. This gives ways to better understand starch structure-property relations, and suggests useful directions for food manufactures to produce functional foods by understanding and differentially controlling the starch gelatinization sub-components.

The effect of pre and post-ultrasonication on the aggregation structure and physicochemical characteristics of tapioca starch containing sucrose, isomalt and maltodextrin

The present research investigated the aggregation behaviors of different levels (4, 8 and 12%) of incorporation of sucrose, isomalt and maltodextrin to pre or post- ultrasonication (400 W, 10 min at 60 °C) by fourier transform infrared spectroscopy (FTIR), microstructure by scanning electron microscopy (SEM), water absorption, pasting by rapid visco analysis (RVA), and thermal by differential scanning calorimetry (DSC). FTIR results showed that the aggregation process between polyol and starch after ultrasonication is more effective than before ultrasonication owning to more hydroxyl groups of polyols are engaged with the hydrogen bonds of starch which is more pronounced peaks at 1500-1750 cm^-1, 1700-2700 cm^-1 and 3000-3700 cm^-1. These findings are in line with the results from SEM analysis. The spots, deformations and cross-linking created by the polyols were more significant after ultrasound assisted pregelatinizion. Impact intensity of polyol on starch granule was reduced in the following order: isomalt > sucrose > maltodextrin. RVA profiles showed that through the incorporation of polyols after sonication, were higher in samples pregelatinized in comparison with those before sonication.

Physicochemical properties and structure of modified potato starch granules and their complex with tea polyphenols

The physicochemical, rheological properties and structure of potato starch and starch-tea polyphenols (TPs) complex modified by enzyme and alcohol was investigated in this study. Cavities on the modified starch granules and morphology change could be investigated by SEM, while significant birefringence observed in complete granules by polarizing light microscope, but disappeared in crashed starch. TPs inhibited the aggregation of amylose and retrogradation of starch-TPs complex, resulting in the decrease of gel strength, and the increase of viscosity and gelatinization stability of starch granules. Fourier transform infrared (FT-IR) spectra showed that intramolecular hydrogen bond could be formed between TPs with modified starch, and the hydrogen bond force formed by starch and TPs was stronger than that between starch molecules. X-ray diffraction (XRD) analysis revealed that three modification methods did not change the crystalline structure of starch, but new diffraction peaks appeared in the four starch-TPs complex, suggesting that the hydrogen bond was incurred by interaction between TPs and amylose to form V-type crystalline. These results demonstrated that the complex formed by TPs and native/modified potato starch could be used in food industrial applications due to the inhibition of starch retrogradation.

Effects of sucrose on pasting, thermal, rheological and textural properties of native and alcohol-alkali-treated waxy rice starch

In this work, the physicochemical properties of native waxy rice starch (WRS) and alcohol-alkali-treated waxy rice starch (AAT-WRS) were studied in the presence of sucrose. The results indicated that the addition of sucrose improved the transparency and freeze-thaw stability of WRS pastes and AAT-WRS pastes. Differential scanning calorimetry showed that the gelatinization temperatures of WRS increased with increased sucrose concentration, but the gelatinization enthalpy increased at low concentration of sucrose and decreased at high concentration. Rheological measurements indicated that sucrose addition had no significant effect on the pseudoplastic shear-thinning behaviors of WRS pastes and AAT-WRS pastes, but changed the apparent viscosity. Dynamic moduli (G' and G″) values of WRS pastes and AAT-WRS pastes with or without sucrose showed frequency dependency and sucrose addition dependency. The elastic behavior was dominant over viscous in the WRS-sucrose mixed pastes, while the AAT-WRS-sucrose mixed pastes was the opposite. The textural paraments of WRS and AAT-WRS before or after retrogradation increased with the increasing concentration of sucrose. These results suggested that sucrose potentially changed the physicochemical properties of WRS and AAT-WRS.

Characteristics of rice starch film blended with sugar (trehalose/allose) and oil (canola oil/coconut oil): Part I - Filmogenic solution behavior and mechanical properties

The concentrations effects of sugars (trehalose and allose) and oils (canola and coconut oil) on the characteristics of rice starch suspension and mechanical properties of rice starch film were studied. The samples were prepared using 3% (w/w) rice starch, with 10% or 30% (w/w) sugar (trehalose or allose) added and 10% or 30% (w/w) oil (canola or coconut). The droplet size of the film suspension increased with increasing oil concentration both in trehalose and allose, which blended with oil. The flow behavior of the film suspensions showed shear-thinning behavior as calculated by the Power Law model. The apparent viscosity tended to increase with the addition of sugar and oil. The breaking stress of the films blended with sugar and oil was less than that of control. On preparation day and after 7 days' storage, the breaking strain tended to increase more with the addition of coconut oil than with that of canola oil. However, breaking stress and breaking strain decreased after 28 days' storage. Adding sugar had correlation with mechanical properties whereas adding oil had correlation with film suspension characteristics, allowed the sugar and oil to interact and inhibited starch chain mobility due to concentration, sugar type, and oil type. PRACTICAL APPLICATION: Trehalose, allose, canola oil, and coconut oil could be used as a plasticizer in a starch edible/biodegradable film system. The preparation process of filmogenic solution was depended on the combination of sugar and oil that could change the flow behavior and affected the mechanical properties of the edible film. The sugar and oil might improve the mechanical properties of the film by a hydroxyl group of sugar and lubricating properties of the oil.

Influence of pinhão starch and natural extracts on the performance of thermoplastic cassava starch/PBAT extruded blown films as a technological approach for bio-based packaging material

Films were produced using the blown extrusion method from blends made with cassava and pinhão thermoplastic starch, compostable polyester (poly(butylene adipate co-terephthalate, PBAT) and natural extracts (rosemary and green tea). The effect of the incorporation of the extracts and the type of starch added in the film properties were investigated following the mixture design (2³ ) approach. Regression models and response surface curves were generated to predict the film properties. The effect of the cold storage (6 °C and 17% of humidity relative, for 60 days) on the film properties was also investigated in order to simulate future applications. All the properties were mainly influenced by the extract type. The incorporation of the extracts decreased the lightness parameter and the films produced with green tea extract were more opaque than those made with rosemary. Starch/rosemary blends were more flexible, while the extract type did not have a significant effect on tensile strength (TS). Film elongation (ELO) ranged from 520% to 719% and might be comparable to some synthetic polymers. The water vapor permeability was improved in approximately 14% with addition of the extracts. The storage conditions, on the one hand, increased the TS, elastic modulus, and opacity of films and, on the other hand, decreased the elongation parameter. The thermal stability of films was not modified by adding extracts or varying the starch type. The results demonstrated that pinhão/cassava/PBAT blends and the natural extracts are a good alternative matrix to produce packagings with adequate mechanical and barrier properties. PRACTICAL APPLICATION: Extruded films produced from cassava or pinhão starch, poly(butylene adipate co-terephthalate) (PBAT) and natural extracts show technological potential to be used as active packaging for food products. Pinhão starch is a great alternative substitute to cassava starch and the incorporation of the commercial compostable polymer (PBAT) is necessary in order to confer suitable mechanical properties to extrusion process. The extrusion blown method, a process widely used by plastic industries, allows the scale-up of bio-based packagings for industrial scale.

Optimization of the Formulation and Properties of 3D-Printed Complex Egg White Protein Objects

The 3D printing of foods is an emerging technique for producing unique and complex food items. This study presents the optimization of a new formulation for 3D printing foods on the basis of a complex system, which contains egg white protein (EWP), gelatin, cornstarch, and sucrose. The effects of different formulations on the rheological properties and the microstructure of the printing system were investigated. The formulation was optimized through response surface methodology, and a central composite design was adopted. The optimum formulation of the 3D mixture printing system was made of gelatin (14.27 g), cornstarch (19.72 g), sucrose (8.02 g), and EWP (12.98 g) in 250 mL of total deionized water with a maximum sensory evaluation score of 34.47 ± 1.02 and a viscosity of 1.374 ± 0.015 Pa·s. Results showed that the viscosity of the formulation correlated with the sensory evaluation score. The rheological properties and tribological behavior of the optimum formulation significantly differed from those of other formulations. A viscosity of 1.374 Pa·s supported the timely flow out of the printing material from the nozzle assisting 3D printability. Thus, 3D printing based on the egg white protein mixture system is a promising method for producing complex-shaped food objects.

Progress in research and applications of cassava flour and starch: a review

The cassava flours and starches have elicited great use in the food and non-food industry. The diversity in cassava genotypes accounts for differences in end-product properties, and would require characterization of cassava varieties for suitability of culinary and processing. This review showed that screening criteria of cassava cultivars end-user properties include proximate contents, amylose content, structural, swelling, gelatinization and pasting characteristics, including freeze-thaw stability properties of cassava-derived flours and starches. Literature shows that the physiochemical properties vary with genetic factors (i.e. genotype). In this review, the amylose content was found to be the main genetic trait for discriminating the cassava varieties for gelatinization and pasting processes including resistant starches. Moreover, cassava derived raw materials (flours and starches) were found to have various application in baking, edible film, syrup, glucose, alcohol, and soups production.

Dynamic rheological properties of corn starch-date syrup gels

The rheological, pasting, and gel textural properties of corn starch blended with date syrup (DS) or sugar (SG) were studied. The average amylose content of the starch was 27.8%. Corn starch gel is considered elastic since the elastic modulus (G') was much greater than the viscous modulus (G″). Different effect between DS and SG on corn starch gel was observed, where SG addition and DS replacement experiments exhibited the highest G'. The tan δ of all samples was in the range of 0.02-0.20 indicating elastic behavior since it is less than unity. The hardness of starch gel ranged from 13 to 146 g and 212-145 for DS replacement and DS addition, respectively. Unlike the replacement experiment, the addition experiment exhibited significant increase in peak viscosity, setback and pasting temperature (p > 0.05). The magnitude of the effect of DS on corn starch gel was more evident compared to SG. This was apparent by looking at the slopes of the linear regression of the log of G' or G″ versus the log of frequency. Based on the information provided here, date syrup application can expand to cover the baking and beverage industries.

Relation between structural, mechanical and sensory properties of gluten-free bread as affected by modified dietary fibers

Gluten-free bread was fortified with modified dietary fibers (wheat bran, resistant starch and inulin) and their effects on water mobility, friction coefficient, thermal behavior, crystalline pattern and textural properties were evaluated. Moreover, time-intensity evaluation was used to study temporal dynamics of sensory attributes of fortified-breads. Dietary fibers increased gelatinization temperature while decreasing gelatinization enthalpy, more notably when inulin was used. X-ray diffraction patterns of bread showed the appearance of new peaks after addition of resistant starch and wheat bran, coinciding with an increase in crumb hardness. In contrast, inulin considerably decreased starch crystallinity in the bread, resulting in a softer crumb. Faster decay and shifting of protons to shorter times were found with incorporation of dietary fibers. Friction coefficient determined by tribology measurement was higher in the breads containing resistant starch and wheat bran compared to other samples. Pearson's correlation analysis indicated the sensory attributes of firmness, chewiness and dryness were positively correlated with instrumental findings. Time-intensity evaluation revealed inulin-fortified bread had the lowest firmness and chewiness with less dryness, whereas resistant starch-fortified bread showed the highest intensity of these descriptors.

Theoretical investigation of the swelling of polysaccharide microgels in sugar solutions

In this paper, we explain the increased swelling of crosslinked polysaccharide microgels by the increase of sugar concentration using a modified Flory-Rehner theory. This theory is validated via the investigation of the swelling of dextran microgels in sugar solutions, which can be viewed as a model system for crosslinked starch in sugar solution and custard. An essential part of our modified theory is that starch perceives the sugar solution as an effective solvent rendering a certain hydrogen bond density. Our simulations show that the often experimentally observed maximum in swelling of starch at 20% sugar concentration is probably due to the fact that equilibrium is not reached within practical time scales. Also, we discuss the use of our theory as a tool in sugar reformulation issues of custard. From simulation results one can produce a state diagram showing which formulations render a creamy, space-filling network.

Quality Enhancement of Tapioca Starch Gel using Sucrose and Xanthan Gum

The quality of starch gel could be enhanced by sugar and hydrocolloid. Sucrose (0, 10 % and 20 %) and xanthan gum (Xan) (0.3125 %) were added in the tapioca starch (TS) gels (25 %w/w TS and TS/Xan gels) for quality investigation. Sucrose increased gelatinization temperatures of starch mixtures. Moisture content and water activity decreased with increasing sucrose content and Xan addition. Freeze–thaw stability of TS and TS/Xan gels with and without sucrose was evaluated. Sucrose and Xan decreased water separation from repeated freeze–thaw cycles. A regression model for predicting water separation from Xan, sucrose and selected freeze–thaw cycle was developed and showed a good predictability. After keeping the TS and TS/Xan gels at 5 °C for 7 and 14 days, the hardness of TS and TS/Xan gels increased with increasing sucrose content but was retarded by adding Xan (p<0.05), suggesting Xan impeded the structure formation contributed from amylose molecule association during cold storage.

Pasting, rheological, and retrogradation properties of low-amylose rice starch with date syrup

Effects of date syrup on pasting, rheological, and retrogradation properties of low-amylose rice starch were investigated using three levels of date syrup (starch:syrup 1:1, 1:2, or 1:3). Measurements were carried out using HR-2 Discovery Rheometer equipped with a pasting cell and parallel plate geometry. The pasting measurements showed that the peak viscosity of the control is significantly higher than the samples with date syrup (p < 0.05), while the final viscosity increases with increased date syrup levels. Addition of date syrup increases the solid-like behavior of the gel in reverse order with increased date syrup levels. Low-amylose starch gel used in this study showed minor changes in elastic modulus (G') during one week cold storage indicting that low-amylose rice starch is resistant to retrogradation. Addition of date syrup slightly resulted in increased retrogradation compared to the control.