Project description:Cassava starch was oxidized using the electrolysis system. Sodium chloride was added to this system at various concentrations from 0.5 to 5.0 % (w/v). The whiteness of modified starches proportionally increased based on the NaCl concentration and human eyes could recognize the difference of color. Under treatment, dents occurred on the surface of starch granule. Concentration of carbonyl and carboxyl groups was increased compared to native starch. Based on X-ray diffraction pattern, oxidized starch kept its A-type. Besides, the ratios of alpha-helix/amorphous regions remained indicating oxidation reaction mainly subjected on amorphous region. Intrinsic viscosity was used to indirectly calculate the average molecular weight of sample. Furthermore, results showed that average molecular weight was significantly reduced (from 2.09-fold to 13.22-fold) based on the reacting NaCl concentration. The increase of NaCl content related to the increase of retrogradation of treated starches. At various temperatures (30-95°C), swelling factor and clarity reflected negative and positive correlations to NaCl concentration.
Project description:This manuscript analyzed physicochemical and structural properties of 30 different types of sorghum starches based on their apparent amylose content (AAC). Current results confirmed that sorghum starch exhibited irregular spherical or polygonal granule shape with 14.5 μm average particle size. The AAC of sorghum starch ranged from 7.42 to 36.44% corresponding to relative crystallinities of 20.5 to 32.4%. The properties of enthalpy of gelatinization (ΔH), peak viscosity (PV), relative crystallinity (RC), degree of double helix (DD), degree of order (DO), and swelling power (SP) were negatively correlated with AAC, while the cool paste viscosity (CPV) and setback (SB) were positively correlated with AAC. Correlations analyzed was conducted on various physicochemical parameters. Using principal component analysis (PCA) with 20 variables, the difference between 30 different types of sorghum starch was displayed. Results of current study can be used to guide the selection and breeding of sorghum varieties and its application in food and non-food industries.
Project description:The world population has crossed seven billion and such a huge population has increased the pressure and considerably affects our ability to feed ourselves. It has now emerged as a new challenge for policy makers, food scientists and other associated people to make food available to everyone. To achieve this, underutilized crops/plants that act as good sources of starch need to be explored. Starch in its native form have certain limitations in its functional properties to be used for different applications. Therefore, it becomes important to explore certain technologies which could be used for modification of properties of starch. During the last decades gamma irradiation has emerged as an efficient processing technique for the modification of starch when compared to the other available processes. This review, aims to summarize the effects of gamma irradiation on various properties of starch such as physicochemical and rheological properties, functional characteristics, thermal behaviour etc. so as to make the starch suitable for various applications in different industries including the food industry.
Project description:The composition, structure, and physicochemical properties of starch in sorghum grains greatly influence the processing and quality of the final products. In this study, 19 sorghum lines were examined to analyze various starch-related characteristics. Correlation analysis of these key traits, revealed a significant correlation between amylose and amylopectin content. Amylopectin was identified as the primary component, averaging 80.75% of the starch content. The distribution of starch chain lengths, as well as the degrees of polymerization and branching, varied significantly among the sorghum lines, maintaining an equilibrium relationship between chain lengths. The size distribution of starch granules also varied among the lines, showing an overall positive correlation. Thermodynamic properties were positively correlated with each other, with correlation coefficients exceeding 0.614. Peak viscosity, trough viscosity, and final viscosity during the pasting process were highly correlated with the setback value, with correlation coefficients of -0.520, -0.651, and 0.618, respectively. 19 sorghum lines were classified into three categories: glutinous, japonica, semi-glutinous. Japonica sorghum exhibited superior thermal stability and viscoelasticity. This study elucidates the relationship between starch fractions, structure and physicochemical properties, providing a crucial theoretical foundation for optimizing sorghum processing for food and industrial applications.
Project description: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.
Project description:This study provides a comprehensive analysis of the physicochemical, structural, and functional properties of starches extracted from five distinct banana varieties. The starches were labeled as follows: 'Nan Tian Huang' starch (NS), 'Da jiao' starch (DS), 'Gui jiao' starch (GS), 'Gong jiao' starch (OS), and 'Hong jiao' starch (HS). The results show that all starches have A-type crystalline structures and contain high levels of resistant starch, ranging from 88.3% to 93.5%. The amylose content ranges from 21.97% to 55.46%. The starches isolated from the five banana varieties are predominantly flat, rod-shaped, and spherical. Particle sizes vary significantly, ranging from 19.75 to 28.65 µm, which contributes to differences in their functional properties. For example, DS demonstrates exceptional functional properties, including high RS content, a low glycemic index, and excellent thermal stability. In contrast, HS starch, despite its high amylose content, exhibits higher enzymatic digestibility and lower freeze-thaw stability. Principal component analysis and correlation analysis revealed that amylose content, thermal properties, and particle morphology are key determinants of the physicochemical and digestive properties of banana starch, emphasizing their interdependence. Additionally, notable differences were observed in the gelatinization properties, thermal characteristics, crystallization, and textural parameters. These findings offer valuable insights into the potential applications of banana starch in functional foods and industrial products, highlighting the importance of starch type in optimizing its functionality.
Project description:The quality standards for the export of chestnuts generate large quantities of rejected fruits, which require novel processing technologies for their safe industrial utilization. This study aimed to investigate the impact of high-pressure processing (HPP) and hydrothermal treatments (HT) on the physicochemical properties of rejected chestnut starch. Chestnuts were treated by HPP at 400, 500, and 600 MPa for 5 min and HT at 50 °C for 45 min. In general, all HPP treatments did not induce starch gelatinization, and their granules preserved the integrity and Maltese-cross. Moreover, starch granules' size and resistant starch content increased with the intensity of pressure. Native and HT chestnut starches were the most susceptible to digestion. HPP treatments did not affect the C-type crystalline pattern of native starch, but the crystalline region was gradually modified to become amorphous. HPP-600 MPa treated starch showed modified pasting properties and exhibited the highest values of peak viscosity. This study demonstrates for the first time that after HPP-600 MPa treatment, a novel chestnut starch gel structure is obtained. Moreover, HPP treatments could increase the slow-digesting starch, which benefits the development of healthier products. HPP can be considered an interesting technology to obtain added-value starch from rejected chestnut fruits.
Project description:This study investigates the effect of ultrasonic-assisted preparation on the structural and physicochemical properties of water caltrop starch-palmitic acid complexes as a function of ultrasound intensity and treatment time. All samples exhibited the characteristic birefringence of starch-lipid complexes under the polarized microscope, and flake-like and irregular structure under scanning electron microscope (SEM), indicating the formation of complexes through ultrasonic-assisted preparation. X-ray diffraction pattern further confirmed the transition from the original A-type structure for native starch to V-type structure for starch-lipid complexes, and the relative crystallinity of starch-lipid complexes increased as the ultrasound intensity and treatment time increased. Attenuated total reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR) analysis indicated a decreasing trend in absorbance ratio at wavenumber of 1022 cm-1/995 cm-1, suggesting that the increase in the complex promoted the self-assembly within the short-range ordered structure, leading to the formation of bonds between the complexes. However, rapid-visco analysis (RVA) demonstrated that the viscosity generally decreased as the ultrasound intensity and treatment time increased, possibly due to the reduction in molecular weight by ultrasound. Differential scanning calorimetric (DSC) analysis revealed that the control starch-lipid complex without ultrasound treatment (US-0-0) exhibited two distinct endothermic peaks above 90 °C, representing Type I (95-105 °C) and Type II (110-120 °C) V-type complexes. However, ultrasound-treated samples showed only one peak around 95-105 °C and increased enthalpy (∆H), which was likely due to the breakdown of amylose and amylopectin, leading to more complex formation with palmitic acid, while the resulting shorter chains in the ultrasound-modified sample favor the formation of Type I complexes.
Project description:Domesticated highland barley is an important starch reserve and has differently colored grains, owing to different genotype backgrounds and cultivation environments. In this study, black, purple, blue, and yellow highland barley varieties were planted under the same cultivation conditions, and their starch distribution, structural characteristics, and physicochemical properties were analyzed. The apparent amylose content was highest in the purple variety (20.26%) and lowest in the yellow variety (18.58%). The different varieties had three subgroups and A-type crystalline structures, but the particle size and relative crystallinity (25.67-27.59%) were significantly different. In addition, the weight average molecular weight (6.72 × 107 g/mol), area ratio of APs to APL (2.88), relative crystallinity (27.59%), and 1045/1022 (0.730 cm-1) of starch were higher in yellow highland barley (YHB), forming a stable particle structure and increasing the Tp and PV of its starch. A cluster heat map showed that starches from differently colored highland barley vary in fine structure, water solubility, swelling power, and thermal and pasting properties. This study provides a reference for the high-quality breeding of colored highland barley and its utilization in food and non-food industries.
Project description:Corn starch was gelatinized and treated with a metagenomic type 1 pullulanase (PulM), increasing the proportion of linear glucan chains. The debranched corn starch (DCS), containing amylose helices, was subjected to complexation with fatty acid molecules at moderate temperatures (50-60 °C). The amylose-lipid complexes prepared using saturated fatty acids, e.g., capric acid (CA) and lauric acid (LA), displayed higher CI values as compared to that of unsaturated fatty acid compounds, e.g., undecylenic acids (UAs) and oleic acid (OA). The DCS-fatty acid complex was estimated to contain about 14% of rapidly digested starch (RDS), 26% of slowly digested starch (SDS), and 60% of resistant starch V (RS-5). RS-5 samples exhibited high resistance toward digestive enzymatic hydrolysis. The surface microdetails of RS-5 were examined by scanning electron microscopy (SEM), depicting small spherulite-like structural aggregates. X-ray diffraction pattern analysis estimated about 46% of the crystallinity of RS-5. Thermal attributes of RS-5 were examined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis, depicting the increase in melting enthalpies after the complexation of fatty acid molecules with debranched corn starch. Comparative DSC thermograms divulged a relatively higher stability of RS-5 as compared to that of RS-3. The findings advocated the potentiality of RS-5 (nondigestible DCS-LA complex) as a functional, valuable ingredient in the food industry.