Starch In Order Research Articles

Correlation analysis of starch molecular structure and film properties via rearrangements of glycosidic linkages by 1,4-α-glucan branching enzyme

The functional characteristics of starch films are significantly influenced by the amylose content and the distribution of the amylopectin chain length. This work used 1,4-α-glucan branching enzyme to molecularly reconstruct corn, pea, and cassava starch in order to examine the association. Films made of both natural and enzyme-modified starch were produced using the casting method. The study investigated the variations in starch films properties and explored the relationship between starch molecular structure and film qualities by correlation analysis. The results showed a significant positive connection (r = 0.954) between the tensile strength and amylose content, as well as a positive correlation (r = 0.939) between the A chains and the elongation at break. The average chain length (r = 0.932) and amylose content (r = 0.902) showed a positive correlation with the degradation temperature, whereas the amylose content (r = −0.946) showed an adverse correlation with the transparency. The B3 chain (r = 0.851) and the average chain length (r = 0.839) both exhibited a positive connection with its contact angle. As a result, our study thoroughly assesses how starch structure affects the characteristics of starch films and offers a fundamental modification pathway for the development of new application areas.

Probing gallic acid–starch interactions through Rapid ViscoAnalyzer in vitro digestion

Phenolic compounds are known inhibitors of starch digestion through binding with α-amylase. However, a growing body of research shows that phenolic-starch interactions at the molecular level may interfere with this inhibition potential. In this study, we evaluated the effect of Gallic Acid (GA) as a model phenolic compound on starch digestion kinetics carried out in vitro in a Rapid ViscoAnalyzer (RVA). The results showed that when GA was added before cooking of starch in order to promote starch-GA complexation, the rate of digestion of starch was similar to that of starch alone, and faster than when GA was added after cooking of starch. The results demonstrated that when GA was introduced after cooking of starch, GA inhibited α-amylase strongly and that inhibition increased with starch paste viscosity only for potato and wheat starches. No correlation was found between starch molecular characteristics and the inhibiting capacity of GA at different starch concentrations. However, the apparent influence of starch chain length distribution suggested that physical effects (such as the absorption of GA at the surface of the starch paste) may play a role in the capacity of GA to inhibit α-amylase.

Rheological and microstructural characterisation of lotus seed milks and their glucono-δ-lactone induced acid-set milk gels: 1. Effect of protein content

The physicochemical and acid gelation properties of lotus seed milks (LSMs), total solid concentrations varying from 5 to 20 wt%, were investigated in comparison with bovine skim milk (10 wt%). LSM was prepared by soaking, blending and milling, filtering followed by α-amylose treatment to hydrolyse the starch in order to reduce its viscosity. The particle size of LSM revealed a multimodal distribution with two main size distributions, a smaller one (∼0.06 and ∼1.5 μm) from protein aggregates as a result of the heat treatment and a larger one (∼1.5 μm and ∼250 μm) likely due to the presence of undissolved protein and cellular materials. A slight shift toward higher sizes, due to further protein denaturation, can be observed after heating at 80 °C for 30 min. As expected, the viscosity of LSM depended on the total solid concentration, and was found to be similar to that of the skim milk when the LSM concentration was around 5 wt%. Addition of glucono-δ-lactone resulted in the formation of LSM gels, and the gelation of LSM occurred when the pH decreased to ∼6 while that of skim milk occurred at pH 5.2. Small deformation rheological measurements showed that it is possible to obtain a LSM acid-gels similar in viscoelastic behaviour (complex modulus G*≈300 Pa after 5 h acidification) to 10 wt% skim milk gel when the concentration of LSM is about 11.1 wt% (same dietary energy as skim milk). Confocal laser scanning microscopy showed that a similar microstructure to skim milk gel is observed for 5 wt% LSM gel, while a denser protein network with voids were observed at high LSM concentrations. The colour of these milk gels appeared white under the naked eye and their syneresis decreased sharply with the increase in concentration with a syneresis similar to that of skim milk when LSM concentration was ≥15 wt%. This study suggested for the first time the potential of LSM to be a strong alternative for the manufacture of non-animal acid milk gels.

Proximate assessment and bioassay of breakfast cereals produced from blends of acha (Digitaria exilis), mungbean (Vigna eadiata) and cashew nut (Anarcadium occidentale Linn) flours

Breakfast cereals were formulated from blends of acha, fermented mungbean and cashew nut (undefatted and defatted) flours. The undefatted and defatted cashew nut flours were used at different levels of substitution (10, 20, 30, 40 and 50 %) with the best blend of acha and mungbean (80:20) flour which was determined by sensory evaluation. Breakfast cereals were produced by toasting (170 oC) a dry heat treatment process to gelatinize and semi-dextrinize the starch in order to generate dry ready to eat products. The samples were subjected to proximate and bioassay analyses. The breakfast cereal was used for a four week bioassay study using eighty four (84) healthy male albino rats weighing 60 - 90 g. The proximate composition showed: crude protein 10.24-20.10 %, moisture content 6.01-8.07 %, crude fat 3.60-24.51 %, crude fibre 4.02-7.07 %, ash 3.39-4.80 % and carbohydrate 46.4- 68.08 %. Feed intake was measured daily while weight gain was measured weekly. Results after the study showed; feed intake 234.22 – 344.55 g, weight gain 34.14 – 80.25 g, feed efficiency 0.14-0.25 and protein efficiency 0.99-1.89. Feeding experiment showed positive increase in weight when the rats were fed the formulated breakfast products. This implies that the products could support growth. No adverse growth rate was observed. Feed intake was also acceptable and compared well with the stable diet for rats. Feed efficiency of the samples compared well with the control diet.

Formation of Intermediate Amylose Rice Starch-Lipid Complex Assisted by Ultrasonication.

Due to the potential reduction in starch availability, as well as the production of the distinct physico-chemical characteristics of starch in order to improve health benefits, the formation of starch–lipid complexes has attracted significant attention for improving the quantity of resistant starch (RS) content in starchy-based foods. The purpose of this research was to apply ultrasonication to produce intermediate amylose rice (Oryza sativa L.) cv. Noui Khuea (NK) starch–fatty acid (FA) complexes. The effects of ultrasonically synthesized conditions (ultrasonic time, ultrasonic amplitude, FA chain length) on the complexing index (CI) and in vitro digestibility of the starch–FA complex were highlighted. The optimum conditions were 7.5% butyric acid with 20% amplitude for 30 min, as indicated by a high CI and RS contents. The ultrasonically treated starch–butyric complex had the highest RS content of 80.78% with a V-type XRD pattern and an additional FTIR peak at 1709 cm−1. The increase in the water/oil absorption capacity and swelling index were observed in the starch–lipid complex. The pasting viscosity and pasting/melting temperatures were lower than those of native starch, despite the fact that it had a distinct morphological structure with a high proportion of flaky and grooved forms. The complexes were capable of binding bile acid, scavenging the DPPH radical, and stimulating the bifidobacterial proliferation better than native starch, which differed depending on the FA inclusion. Therefore, developing a rice starch–lipid complex can be achieved via ultrasonication.

X-ray Diffraction for Detecting Starch Adulteration and Measuring the Crystallinity Indices of the Polymorphic Modifications of Starch

Introduction: Starch is widely used in the food industry and biotechnology, including for manufacturing food packaging materials. Native starches from various sources exist in the form of three polymorphic modifications (A-, B- and C-types) differing in their crystal structure, which has an indirect effect on their physicochemical and technological properties.Purpose: To properly and efficiently use starch as a raw material for biotechnology, one needs to preliminarily identify its polymorphic modification and crystallinity, as well as detect and discard adulterants or substandard raw materials. X-ray diffraction is suggested to be a rapid and accurate method for solving the outlined problems.Methods: In this study, properties of commercial starch from various plant sources (corn, rice, wheat, potatoes, peas, and tapioca) were analyzed by X-ray diffraction and scanning electron microscopy.Results and conclusion: Starch of some brands was shown to be adulterated: the more expensive potato starch was replaced with cheaper corn starch. The crystallinity indices were determined for all the selected samples; the crystal structure of corn starch was found to be most highly ordered. Contrariwise, the C-type pea starch was characterized by the lowest degree of crystal structure ordering. The findings obtained in this study show that it is necessary to preliminarily determine the source of starch in order to identify its polymorphic modification, as well as physical and chemical properties by X-ray diffraction. This information will be demanded for developing the new types of functional foods and reproducing the currently used biotechnologies.

Starch hydrogels as targeted colonic drug delivery vehicles

Targeted colonic drug delivery systems are needed for the treatment of endemic colorectal pathologies, such as Crohn's disease, ulcerative colitis, and colorectal cancer. These drug delivery vehicles are difficult to formulate, as they need to remain structurally intact whilst navigating a wide range of physiological conditions across the upper gastrointestinal tract. In this work we show how starch hydrogel bulk structural and molecular level parameters influence their properties as drug delivery platforms. The in vitro protocols mimic in vivo conditions, accounting for physiological concentrations of gastrointestinal hydrolytic enzymes and salts. The structural changes starch gels undergo along the entire length of the human gastrointestinal tract have been quantified, and related to the materials' drug release kinetics for three different drug molecules, and interactions with the large intestinal microbiota. It has been demonstrated how one can modify their choice of starch in order to fine tune its corresponding hydrogel's pharmacokinetic profile.

Gamma radiation modification of cassava starch and its characterization

AbstractRadiation technology has been recognized as a potential tool to modify starches in order to enhance their solubility and enzymatic digestion, hence improving their applicability in food industry. In the present study, the local cassava starch was irradiated under 60Co gamma source with the absorbed dose ranging from 1 to 10 kGy, and the obtained radiation‐modified starches were characterized. The microstructure of the initial cassava starch was not much changed although several starch granules were deformed or even fragmented by gamma irradiation as observed in the scanning electron microscopy images. Water solubility of the irradiated starch was significantly increased, and their viscosity was much reduced by radiation degradation. Gamma radiation broke glycosidic bonds in starch chains into smaller molecules with lower molecular weight, whereby increased the water solubility of cassava starch. Radiation scission also partly decreased the crystallinity of the starches irradiated with dose higher than 5 kGy as indicated in their X‐ray diffraction patterns. The Fourier transform infrared spectra of irradiated starches revealed the reduction in intensities of stretching vibration characterized for OH, CH, and COC groups of starch molecules. Thus, gamma irradiation can be used to modify cassava starch for further applications.

Structural and Physicochemical Properties of Tunisian Quercus suber L. Starches for Custard Formulation: A Comparative Study.

The aim of the present study was to extract starch from acorn (Quercus suber L.) fruits using water and alkaline methods. Structural and functional properties of extracted starches were investigated and compared to those of corn and modified starches in order to determine their innovative potential application in food industry. The yield of extraction using the two methods was about 48.32% and 48.1%. The isolated starches showed low moisture, fat and protein contents, revealing high purity and quality. Additionally, the starch extracted using the alkaline method (AAS) showed higher lightness (60.41) when compared to starch isolated using hot water (WAS). However, the lightest white color was found for studied commercial starches. Moreover, AAS starch exhibited the highest swelling power, solubility and water absorption, followed by WAS and commercial starches. Results showed that extracted acorn starches were characterized by greater enthalpy and gelatinization temperatures. Similar observations were noted using FT-IR spectra analysis for all analyzed starches. In addition, granule starches observed using scanning electron microscopy were found to be spherical and ovoid. However, from the analysis by X-ray diffraction, a crystalline pattern of C-type was found for acorn starches, while commercial starches presented an A-type pattern. As an innovative food application, these underexploited acorn starches were valued and served to produce new custards with improved functional properties and better microstructure when compared to commercial custard.

Impact of starch nanocrystals on the physicochemical, thermal and structural characteristics of starch-based films

The incorporation of starch nanocrystals (SNCs) in starch films can be a way of increasing their applicability. Therefore, the objective of this study was to develop SNCs from rice and potato starch and apply them in films of native rice starch and hydrolyzed rice starch in order to observe the effect of these nanomaterials on the films’ properties. The SNCs were produced by hydrolysis for 5 and 7 days and characterized. The films were produced by the casting technique and the SNCs were added at concentrations of 0.1% and 0.3%. The films were characterized in terms of physicochemical, thermal and structural properties. The SNCs showed solubility above 70% while the control starches had solubility around 20%. The addition of SNCs increased the crystallinity of all films produced. The addition of 0.1% rice SNCs to native starch films reduced water vapor permeability by 64% compared to the control. The incorporation of 0.1% potato SNCs reduced the solubility to 14%. The application of 0.3% rice SNCs and 0.1% potato SNCs in native starch and hydrolyzed starch films reduced the surface roughness and fracture, making these films more cohesive. Therefore, SNCs act as a structural reinforcing agent, improving several properties of the films.

Arrowroot starch ( Maranta arundinacea ) as a bread ingredient for product development

The goal of this study was to characterize the technological-functional, physical and thermal properties of arrowroot starch in order to better determine its role and effectiveness in the food industry, and then to evaluate its effect on bread properties. Arrowroot starch was characterized in relation to microstructure, x-ray diffraction, infrared spectroscopy, thermogravimetric, and technological-functional properties. Thereafter, breads with different wheat-arrowroot concentrations were produced, and characterized. Results evidenced that arrowroot starch presented monomodal particle size distribution, and circular, ellipsoid, and oval granules. Technological-functional properties showed increase in swelling power, solubility and water absorption index with the increase of temperature. Wheat-arrowroot bread were homogeneous and visually similar to control breads. Crumb hardness and volume were not significantly affected by arrowroot starch concentration when up to 30% of wheat flour was substituted. Therefore, it could be concluded that arrowroot starch represents a promising raw material to be explored in different food applications. Practical applications This study investigated the potential properties of arrowroot starch and its use in bread formulation, which finally provides to be a useful strategy to food industries in order to meet the suitable use of “new” materials for developing product. The results demonstrated that arrowroot starch presented interesting technological-functional and thermal properties in order to be used in bread development. Wheat-arrowroot breads were well produced, homogeneous, and visually similar to control breads, and bread produced with 30% of arrowroot starch presented crumb hardness and volume similar to control bread.

Enhancement of Solubility and Dissolution Rate of Curcumin Using Porous Starch by Solid Dispersion Technique

The poor dissolution characteristics of biopharmaceutical class II drugs are a major concern for scientists in thepharmaceutical industry. Solid dispersion is introduced as a novel method for enhancement of solubility. Class IIdrugs are low solubility and high permeability according to the biopharmaceutical classification system and arepromising candidates for improving solubility and bioavailability through solid dispersion. The purpose of the present attempt is to prepare a solid dispersion of curcumin and porous starch in order to increase the solubility and dissolution of drugs that are poorlysoluble. Solid dispersions (SDs) of BCS-II drugs were prepared by ball milling in ratio of drug: polymer i.e. curcumin: porous starch (1:0.5, 1:1, 1:2 and 1:3). Further, SDs were investigated by solubility, FTIR, XRD, DSC, micromeritics, and in-vitro dissolution. . Conclusively, porous starch offers a hydrophilic matrix to deliver poorwater soluble drugs and Solid dispersion system have demonstrated an improved performance. Solid dispersionsystem have demonstrated an improved performance

Effect of solvent concentration in sago starch fractionation

The research studied the effect of solvent concentration in the fractionation process from sago starch in order to achieve the amylose fraction. The amylose is aimed to be applied as a functional material such as for edible film. The fractionation process is carried out by utilizing N-butanol as the solvent with a variety of concentration (10, 12.5 and 15%). The highest result is achieved from the concentration of butanol of 15%. It resulted in a yield of 31.19%, a 30.78% solubility, and swelling ability of 2.37%. The spectra from Fourier transform infrared showed the same specific peaks of the obtained amylose. However, each of them shows different intensity means the fractionation process affect the resulted amylose.

Dual modification of achira (Canna indica L) starch and the effect on its physicochemical properties for possible food applications.

The aim of this study was to evaluate the effect of acid hydrolysis and succination upon single and a combination of both of them as a dual modification on the morphological, structural, thermal, and pasting profile of the achira starch in order to expand its potential food applications. The surface of achira starch granules was eroded with acid hydrolysis, while the succination resulted in the formation of pores or cavities, having a slight impact on the crystallinity and the gelatinization enthalpy. Succinated starch presented the lowest transition temperatures (To = 60.29°C, Tp = 65.03°C and Te = 69.86°C) compared to other starches in this study. The succination increased the final viscosity (3808 cp) when compared with the native starch (3114 cp), while acid hydrolysis resulted in a decreased value (735 cp). These are desirable properties for its possible use as an additive in bakery industry processes.

Microgels prepared from corn starch with an improved capacity for uptake and release of lysozyme

The combination of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidization and annealing was applied to modify structural properties of corn starch in order to obtain starch polymer microgels. Microgels were characterized by X-ray diffraction, ATR-FTIR and thermogravimetry analysis (TGA). The effects of microgels on the uptake and release of lysozyme were also analyzed. The formation of oxidized microgels through the crosslinking between starch molecules and sodium trimetaphosphate was confirmed by X-ray diffraction. The ATR-FTIR analysis suggested that TEMPO-oxidation results in the formation of carboxyl groups. TGA data indicated that oxidized-annealed microgels had less thermal stability than oxidized microgels. Furthermore, the oxidized-annealed microgels had an improved capacity for uptake and release of lysozyme. At this stage of the exploration, microgels prepared from corn starches by annealing and oxidation is simple and efficient.

Morphological, structural and cytotoxic behavior of starch/silver nanocomposites with synthesized silver nanoparticles using Stevia rebaudiana extracts

The synthesis of silver nanoparticles (AgNPs) using a Stevia rebaudiana aqueous extract and their dispersion in starch in order to obtain starch/AgNps nanocomposites are shown in this study. The AgNPs and the starch/AgNPs nanocomposites have been characterized by ultraviolet–visible spectroscopy, optical microscopy, high-resolution transmission electron microscopy, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis. Furthermore, the interaction of starch/AgNPs nanocomposites with a MCF-7 breast cancer cell line is analyzed. AgNPs with an average size around 15–20 nm have been obtained. starch/AgNPs nanocomposite morphology changes with the content of silver (3, 5 and 8 mM), from totally separated and dispersed nanoparticles to ribbon-type morphology. The diffraction pattern of the starch/AgNPs-3 nanocomposite indicates the formation of silver chloride nanoparticles (AgClNPs). A cytotoxic behavior of starch/AgNPs-3 nanocomposite on MCF-7 cancer cells with less damage to normal cells is observed. Hence, the high dispersion of the AgNPs or AgClNPs in starch could be influencing the selective cytotoxic behavior. Thus, this study proposes the generation of biocompatible composite materials, with AgNPs immobilized on starch. These materials have selective action against breast cancer cells, where the selectivity is controlled through the AgNPs dispersion on the biopolymer.

Thermal, morphological and structural characterization of a copolymer of starch and polyethylene

The objective of this paper was to perform a copolymerization between polyethylene and starch in order to obtain new environmentally friendly materials. The copolymer obtained was characterized thermally, morphologically and structurally, including its pasting profile. The starch-g-PE copolymer showed lower thermal stability compared to the control materials. FTIR analysis determined that the chemical bond signal between the starch and polyethylene in the copolymer overlaps with the native starch signals. The signal from this chemical bond was assigned by proton NMR spectroscopy at δ 4.45 ppm. X-ray studies of the copolymer showed a material with more amorphous characteristics compared to native starch. SEM analysis demonstrated the presence of cracks in the starch granules which favored the chemical interaction between the polymers. The pasting behavior of the copolymer was less pronounced compared to native starch. Therefore, the copolymerization of both polymers could be an alternative to recycle polyethylene and make biodegradable materials.

Insecticidal activity of spray dried microencapsulated essential oils of Rosmarinus officinalis and Zataria multiflora against Tribolium confusum

Rosmarinus officinalis and Zataria multiflora (Lamiaceae) essential oils (EOs) contain components with insecticidal properties that can be used as pesticides for stored product pests. In the present study, they were encapsulated in octenyl succinic anhydride (OSA) - starch in order to test their insecticidal activity against Tribolium confusum. First an oil-in-water emulsion was prepared and afterwards, it was dried by spray-drying technique. The emulsions were characterized regarding particle size (461–854 nm), stability and encapsulated oil efficiency (68–88%). Also, solid formulations were characterized by particle size (8.29–11.35 μm), encapsulation efficiency (5–52%) and water activity (0.19–0.26). Further, the release rate at storage conditions (at 27 ± 3 °C and 70–75% relative humidity in the dark) was measured over a period of 40 days. The insecticidal activity against T. confusum was determined by specific bioassays performed at 27 ± 3 °C temperature and 70–75% relative humidity in the dark. Five concentrations were used for estimation of fumigant toxicity of rosemary and Zataria oils after 72 h exposure in adult beetles. Fumigant toxicity results revealed that microencapsulated oils were more effective than non-formulated oils against beetles in long time. Similarly, it was demonstrated that microencapsulation of the essential oils increases their persistence: non-formulated oils have not insecticidal activity after 15 days of the storage period, whereas at the same period, the mortality rate against T. confusum of rosemary and Zataria microencapsulated oils was 46.6 and 35.5%, respectively.

Characterization of corn, cassava, and commercial flours: Use of amylase-rich flours of germinated corn and sweet potato in the reduction of the consistency of the gruels made from these flours-Influence on the nutritional and energy value.

Malnutrition appears in weaning age and is usually due to weaning food which is of low nutritional value. This problem led us to investigate the study of the physicochemical and functional properties of cassava flours and corn flours, and the fluidification of the gruels made from these flours by germinated yellow corn and sweet white potato flours. To do this, the approximate chemical composition, physical and functional properties, and ability of amylase‐rich flours to digest the starch in order to reduce consistency were evaluated. From these analyses, it emerges that the chemical composition, and physical and functional properties are influenced by the nature and the treatment undergone by the flours. It appears that the amylase‐rich flours that we used at a concentration of 1%–3% during the preparation of the gruels significantly reduced their consistencies. Given their strong liquefying power, this reduction was more marked with germinated corn flour where 1% permits to obtain desired consistency with 21.50 g of DM of bitter cassava flour, thereby multiplying the energy density and nutritional value of this flour by 5.18. It also appears that the action of flours rich in amylases was depending on the concentration, the nature of the flour, its composition, and the treatment undergone. In view of all these results, we can therefore consider the formulation of a weaning food with the consistency, and energy and nutritional value necessary for the proper growth of children.

The effect of malting on the crystallites and microstructure in Greek barley cultivar using x-ray diffraction and microscopic analysis

Introduction: Malting was generally used to produce fermentable sugars from starch in order to permit alcoholic fermentation. Variation in the starch microstructure and crystallinity affects its water solubilisation as well as and its breakdown from the enzymes Objectives: The starch microstructure is explored in order to understand and possibly modify the malting process of a Greek barley variety if needed. To address the issue, a combination of microscopy and X-ray diffraction inspection methods were used to evaluate the variation of the starch granule morphology and the degree of crystallinity of starch. Methods: The effect of malting on the microstructure of barley starch was investigated for one Greek barley cultivar (Seirios). The barley seeds were provided from ELGO-DEMETER, Institute of Plant Breeding and Genetic Resources (Thessaloniki, Greece). The steeping was performed at 14°C (several soaking and aerating circles) until barley reached the desired moisture content. Then the steeped barley was allowed to germinate at 15°C. The germination was stopped by drying at 40-45°C for at least 20h (dry malt). The malt was obtained by kilning for 6 hours at 100°C. The barley, dry malt and malt were milled to pass through a 0.8mm screen before being analysed. Light microscopy photographs with Congo red staining were used to identify variation in the starch granule morphology. Moreover, the x-ray diffraction analysis of the barley meal, dry malt and malt millings were obtained. Finally, the analysis of X-ray diffractograms was performed in order to calculate relative crystallinity and the crystallite size of the starch. Results: The results demonstrated variations in the morphology of the starch granules. The stained light microscopy photographs revealed that the starch granules in barley were round, greater, smooth, and granular, and that of the dry malt and the malt appeared smaller and more elongated with scratches on the surface. The stained confocal microscopy photographs showed the beginning of the starch damage on the surface of the granules. X-Ray diffractographs revealed that the crystallinity of the barley starch was increased during dry malt production and then decreased during kilning but still remained greater than the native barley starch. Conclusions: Malting under the specified conditions, affected the morphology of the starch granules of Seirios variety as well as the crystallinity of the starch suggesting the partial degradation of the starch during steeping and germination as well as during kilning.