Gelatinization Properties Of Starch Research Articles

Studies on Physicochemical Properties of Rice Bean (Vigna umbellata) Starch: An Underutilized Legume

Starch is a reserve carbohydrate present in plants. It is an important component for maintaining various quality attributes like texture, consistency, thickening in the food industry. The aim of the present study was to isolate starch from a legume named jack bean that is not very much famous and considered as underutilized-legume. The isolated starch was studied for various physicochemical properties. One-way analysis of variance was used in this study. The starch was isolated as a white powder from the dry legume by using standard method and the starch yield was observed to be 25.79%. Legume starch was further assessed for the chemical composition. The moisture, ash, fat, protein, fiber and carbohydrate content were 9.56%, 0.35%, 0.21%, 0.69%, 0.33%, and 89.19% respectively. The apparent and total amylose content was 37.62% and 40.83% with least gelation concentration at 6% of starch gel. Starch was further assessed for functional properties. The leached amylose displayed a rise in content from 6.56% to 9.50% with the corresponding increase in temperature from 65°C to 95°C that may affect gelatinization properties of starch. The water absorption capacity was 3.60 g/g while oil absorption capacity was 3.54 g/g. Further, the emulsion stability and emulsion capacity of native starch was 79.00% and 68.33% respectively that showed good stability of emulsion. Similarly, the swelling power and solubility of rice bean starch increased with the increase of temperature from 55-95°C. However, the opposite trend was observed for an increase in starch concentration from 1-4%. The effect of different concentrations at 6, 8 and 10% on freeze-thaw stability and storage studies showed that the expelled water decreased with the rise in starch concentration up to three consecutive storage days while no change was observed later during frozen gel storage. It showed good freeze thaw stability of starch. This underutilized legume attracted more attention from researchers due of its affordability and ease of availability. In dry farming circumstances with limited soil fertility, the legume yield consistently. Thus, this neglected legume that has minimal agronomic development but many qualities is a good substitute for starch. However, thorough study on the unique functional properties and other qualities of starch from rice bean has not been carried out. The results of this underutilized legume starch can provide opportunities to starch researchers and to the food industries that are frequently using conventional sources of starch from cereals, tubers and rhizomes.

The Effects of Naematelia aurantialba on the Pasting and Rheological Properties of Starch and the Research and Development of Soft Candy.

To study the effects of Naematelia aurantialba (NA) on the rheological and gelatinization properties of starch, the processing methods of NA were diversified. In this study, the gelatinization and rheological properties of corn starch (CS) and edible cassava starch (ECS) were investigated by adding NA with different mass fractions. Starch soft candy was prepared using NA, CS, and ECS as the main raw materials. Rheological studies showed that both CS-NA and ECS-NA exhibited elastic modulus (G') > viscosity modulus (G″), implying elastic behavior. G' was such that CS+1%NA > CS+5%NA > CS+3%NA > CS > CS+2%NA > CS+4%NA > ECS+4%NA > ECS+3%NA > ECS+5%NA > ECS+2%NA > ECS+1%NA > ECS. The gelatinization implied showed that after adding NA, the pasting temperature of CS-NA and ECS-NA increased by 1.33 °C and decreased by 2.46 °C, while their breakdown values decreased by 442.35 cP and 866.98 cP, respectively. Through a single-factor test and orthogonal test, the best formula of starch soft candy was as follows: 0.4 f of NA, 10 g of white granulated sugar, a mass ratio of ECS to CS of 20:1 (g:g), 0.12 g of citric acid, 1 g of red date power, and 16 mL of water. The soft candy was stable when stored for two days. This study offers a new direction for the research and development of NA starch foods.

The important role of starch fine molecular structures in starch gelatinization property with addition of sugars/sugar alcohols

The relationship between the fine structure of starch and its gelatinization properties is not well studied, particularly in relation to the influence of sugar or sugar alcohol. In this study, seven starches with distinct molecular structures were investigated to determine how different sugars and sugar alcohols affect their gelatinization properties. The inclusion of sugars and sugar alcohols resulted in a significant elevation of starch gelatinization temperatures (∼ 8 °C), especially with sucrose, isomaltose and isomalt. Nevertheless, the influence of these sugars/ sugar alcohols on the gelatinization temperature range and enthalpy change varied depending on the particular starch varieties. According to the correlation analysis, sugars and sugar alcohols mainly exert their impact on the starch gelatinization temperature range and enthalpy change by possibly interacting with amylose chains possessing a degree of polymerization ranging from 100 to 1000 (p < 0.05) and inhibiting the amylose leaching during gelatinization. These findings help a better understanding of the complex relationship between starch fine structure and gelatinization properties under the influence of sugars and sugar alcohols.

Effects of acid hydrolysis level prior to heat-moisture treatment on properties of starches with different crystalline polymorphs

Highly crystalline starches find applications as resistant starch because of their improved thermal stability and reduced enzyme susceptibility. Both acid hydrolysis (AH) and heat-moisture treatment (HMT) have been used to alter starch gelatinization properties and digestibility. This study investigated the effects of varying AH levels (0–9%) prior to HMT on the structures and properties of starches with different crystalline polymorphs, including the A-type corn starch, the B-type potato starch, and the C-type pea starch. HMT resulted in significant increases in gelatinization temperatures and significant decreases in gelatinization enthalpy and α-amylase digestion for all three starches. When combined AH with HMT, all three starches generally displayed increases in gelatinization temperatures, gelatinization enthalpy and relative crystallinity with increasing AH level, but the susceptibility to α-amylase varied with starch type and AH level. Acid preferentially hydrolyzed the amorphous regions involving amylose and amylopectin branch points, and increased hydrolysis levels yielded greater amounts of linear chains that were capable of reorganizing into crystallites during HMT. The greater AH level, up to 9%, combined with HMT promoted the formation of more thermally stable crystallites for starches with different crystalline polymorphs.

Measurement of starch gelatinization using a spectrophotometer

Starch gelatinization behaviors significantly affect functionalities of starch-based foods and materials. Various analytical techniques have been used to measure starch gelatinization behaviors, but these instruments are not commonly found in laboratory and industrial settings. This study aimed to investigate whether spectrophotometer, a more ubiquitous instrument, could be used for measuring starch gelatinization. The relative crystallinity and enthalpy of starch granules remained unchanged during heating at 54–56 °C, but decreased at higher temperatures. The transmittance of starch slurry at 620 nm also remained unchanged at 54–56 °C, but significantly increased at higher temperatures. Furthermore, the changes in transmittance were negatively and significantly correlated with both the changes in relative crystallinity and enthalpy. This suggested that changes in transmittance of starch slurry during heating could be used to evaluate the temperature at which starch gelatinization occurred. However, further research is needed to determine if the changes in transmittance of starch slurry can be used to evaluate the thermostability of starch granules during heating. These findings offer a simple and feasible pathway for measuring starch gelatinization properties using ubiquitous spectrophotometer.

Untargeted UHPLC–Q-Exactive-MS-based metabolomics reveals associations between pre- and post-cooked metabolites and the taste quality of geographical indication rice and regular rice

Geographical indication (GI) rice refers to the rice of specific geographical origin, which tends to have a good taste quality and a high commodity price. Rice is favored for its soft texture and chewiness after cooking. However, GI rice is also plagued by rice fraud. Understanding the reasons for the excellent taste quality of GI rice and identifying its geographical origin can help maintain the stability of the rice market and promote the development of the rice industry. In this study, we determined the taste quality of rice. Untargeted metabolomics based on UHPLC–Q-Exactive-MS was used to identify metabolites in GI and regular rice before and after cooking. Our findings suggested that GI rice showed lower protein and amylose content, resulting in higher starch gelatinization properties and taste quality. This study identified 520 metabolites, among which 142 and 175 were significantly different between GI and regular rice, before and after cooking, respectively. The increased variety of metabolites after cooking was significantly negatively correlated with the taste quality of rice. GI rice was lower in amino acids and lipid metabolite content before and after cooking, which may be the reason for the excellent taste quality. Through linear discriminant analysis, we found that the differential metabolites of rice after cooking were more accurate in discriminating rice from different geographic origins, up to 100%. This work gained new insights into the metabolites of GI rice, which explains its excellent taste quality. The rice metabolites after cooking could be used for more accurate geographical identification of rice.

Impact of red flour beetle infestations in wheat flour and their effects on dough and bread physical, chemical, and color properties

The impact of Tribolium castaneum on the quality and technological suitability of bread-making wheat flour was evaluated. The aim of this study is to investigate whether insect-infested flours can be used, after pest removal, avoiding the common use of insecticides and flour waste. The tests were carried out with wheat flour infested red flour beetle with 500 adults/kg (N1), 1000 adults/kg (N2) and 2000 adults/kg (N3), for two weeks. Flour color, total starch, protein and water contents, mineral composition and flour acidity were studied. The technological properties of the respective doughs and of bread were characterized. The results showed that infested flours acidity was significantly higher (N1, N2 and N3 = 0.3 g H2SO4/100 g) than the control (0.1 g H2SO4/100 g), the total starch content decrease, from 78 g (control) to 70 g/100 g dm (N3), and protein content did not significantly change, 7 g/100 g (control) to 8 g/100 g (N2); flour infested showed darker greyish tone which colour differences ΔE higher than 5, while the bread crust was lighter; the gelatinization properties of starch were slightly influenced by degree of infestation with gelatinization temperature reduction of about 5°c. There was not impact on the structure of the doughs from infested flours measured by rheology. The extensibility of the doughs, before and after fermentation, was moderately affected by the insects. For the respective breads, they kept their softness for longer, without significant volume change. These results encourage insect tolerance on grains and derivatives, avoiding chemical toxic insecticides and food waste. This pretends to be a contribution to pest management and decision support systems, prevention, and control of losses, relevant subject to stored products.

The Effects of Starch Molecular Fine Structure on Thermal and Digestion Properties of Rice Starch.

Whole white rice is a major staple food for human consumption, with its starch digestion rate and location in the gastrointestinal tract having a critical role for human health. Starch has a multi-scale structure, which undergoes order-disorder transitions during rice cooking, and this structure is a major determinant of its digestibility. The length distributions of amylose and amylopectin chains are important determinants of rice starch gelatinization properties. Starch chain-length and molecular-size distributions are important determinants of nucleation and crystal growth rates, as well as of intra- and intermolecular interactions during retrogradation. A number of first-order kinetics models have been developed to fit starch digestograms, producing new information on the structural basis for starch digestive characteristics of cooked whole rice. Different starch digestible fractions with distinct digestion patterns have been found for the digestion of rice starch in fully gelatinized and retrograded states, the digestion kinetics of which are largely determined by starch fine molecular structures. Current insights and future directions to better understand digestibility of starch in whole cooked rice are summarized, pointing to ways of developing whole rice into a healthier food by way of having slower starch digestibility.

Different nitrogen fertilizer application in the field affects the morphology and structure of protein and starch in rice during cooking

Nitrogen fertilization is one of the most important cultivation practices that affects the eating quality of rice. During the cooking process, nitrogen fertilizer application in the field changed the structure of protein and starch during cooking, which eventually reduced the rice eating quality. However, the morphology and structure of rice during cooking under high nitrogen fertilizer application in the field have not been explored. The relationship between the morphological and structural changes of rice protein and starch during cooking and the rice eating quality has not been studied. In this study, we conducted field trials at two nitrogen fertilizer levels (0 N and 350 N), and the rice was cooked after harvest. Our results showed that the peak viscosity of rice flour was 3326 cp and 2453 cp at 0 N and 350 N, respectively, and the peak viscosity of rice starch was 3424 cp and 3378 cp, respectively. Rice proteins played an important role in the starch gelatinization properties and thermodynamic properties. High nitrogen fertilizer application increased the protein content of rice from 5.97 % to 11.32 %, and more protein bodies adhered to the surface of amyloplasts eventually inhibiting starch gelatinization. The rice proteins could bind to amylose–lipid complexes during cooking, promoting the formation of V-type diffraction peaks. What is more, under high nitrogen fertilizer, rice protein had more β-sheets, which slowed the entry of water into the interior of starch molecules and prevented the destruction of the short-range ordered structure of starch. Our study provides the possibility to further improve the eating quality of rice under nitrogen fertilizer treatment.

Revealing color change and drying mechanisms of pulsed vacuum steamed Cistanche deserticola through bioactive components, microstructural and starch gelatinization properties

Cistanche deserticola is a famous herbal medicine and has been used worldwide for its kidney-tonifying and anti-aging values. This study investigated the effects of pulsed vacuum steaming (PVS) on bioactive phenylethanoid glycosides (PhGs), total soluble sugars, polysaccharides, color, drying characteristics, microstructure, and starch gelatinization properties of Cistanche deserticola. PVS pretreatment significantly increased PhGs and soluble sugar content while reduced the polysaccharides content. And increasing the material core temperature to 75 °C at the largest diameter was proposed as the optimal steaming condition and the PhGs content was increased by 1.11 times compared with that by atmospheric steaming. The color of steamed samples changed to oily black due to Maillard reaction. PhGs content was significantly (P < 0.05) positively correlated with total color difference (ΔE). Steaming until the ΔE value of 15.95 could achieve the maximum accumulation of PhGs, corresponding to the highest increasing ratio of echinacoside and acteoside. Starch was completely gelatinized and formed a barrier layer adhering to the cell surface when the material core temperature reached 75 °C at the largest diameter, explaining why after steaming the Cistanche deserticola drying time was prolonged by 85.71 %. The study can provide an innovative steaming technology and optimal process parameters for obtaining high-quality Cistanche deserticola decoction pieces, as well as propose a non-destructive testing method to quickly predict PhGs content based on color parameters during the steaming process.

Continuous microwave drying of germinated red adzuki bean: Effects of various drying conditions on drying behavior and quality attributes

This study investigated the effects of various drying conditions involving microwave power, air velocity, and sample mass on the drying behavior, starch gelatinization properties, and gamma-aminobutyric acid (GABA) content of germinated red adzuki bean (GRAB) under continuous microwave drying. Increasing the microwave power and lowering the sample mass can promote GRAB drying and shorten the total drying duration; improving the air velocity limited the temperature elevation of GRAB to affect water removal to some extent. The drying rate had only the rising- and falling- rate stages throughout the drying process. Microwave drying lowered the gelatinization temperature and enthalpy to facilitate the starch gelatinization of GRAB. The microwave power and sample mass had significant effects on the GABA content of the final dried GRAB. This study may provide guidance for understanding and follow-up improving the continuous microwave drying production of germinated bean products like GRAB. Practical applications GRAB is consumed as a nutritional food source due to its high starch and protein contents, low fat, and rich bioactive ingredients like GABA. Drying processing is a needed step for fresh GRAB to facilitate long-term storage and quality retention. This study evaluated the drying behavior and quality attributes of GRAB in a continuous microwave belt dryer, and the research results have underlying application potential and may provide guidance for microwave drying production of germinated bean products like GRAB.

Influence of whey protein isolate on pasting, thermal, and structural characteristics of oat starch

We investigated the effects of different concentrations of whey protein isolate (WPI) on oat starch characteristics in terms of pasting, thermal, and structural properties. The pasting properties of the starch showed that hot paste viscosity increased with the addition of WPI in the system, and relative breakdown decreased. Thermal analysis showed a significant effect of WPI on oat starch by increasing the peak temperature of differential scanning calorimeter endotherms. The X-ray diffraction and Fourier transform infrared spectroscopy studies revealed that WPI increased the ordered structuration of starch paste, as evident by an increase in relative crystallinity; in addition, a decrease in infrared bands at 1,024 cm-1 and 1,080 cm-1 suggested decreased gelatinization of oat starch granules. Overall, WPI at different concentrations affected the oat starch gelatinization properties.

Endogenous alpha-amylase alters the pasting properties of starch during starch separation by proteases

The role of amylase is often neglected in the separation of starch by protease despite the fact that it likely impacts the properties of starch. This study aimed to explore the effects of endogenous alpha-amylase on the pasting properties of starch during isolation using protease. A strategy is developed according to prevent the influence of alpha-amylase on starch pasting properties. Decreased pasting viscosity was observed in the presence of endogenous alpha-amylase while an increase in reducing sugar during incubation decrease viscosity due to starch degradation. The addition of acarbose effectively inhibits starch degradation due to endogenous alpha-amylase. However, acarbose does not appear to affect protease activity. Thus, a combination of protease and acarbose can effectively prevent interference from endogenous alpha-amylase without affecting the gelatinization properties of starch.

Effects of acid hydrolysis on the evolution of starch fine molecular structures and gelatinization properties

Effects of acid hydrolysis on amylose molecular structures and their relations to starch gelatinization properties were investigated. First-order kinetics models were applied to fit the evolution curve of starch chain-length and molecular size by acid hydrolysis treatment. Results showed that a single hydrolysis phase was involved in the degradation of waxy maize starch chains, while two distinct phases existed for the degradation of maize, high amylose maize and sago starch chains. The fast hydrolysis phase involved degradation of amylose chains with DP > ~300 and amylopectin long intra-cluster branches, while amylose chains with DP < ~300 was involved in the slow hydrolysis phase. Amylose molecules with DP ~ 300 were proposed to impact starch gelatinization properties by interaction with cut-off amylopectin double helices and formation of amylose crystallites/entanglements. This study could help food industry precisely control amylose molecular structures by acid hydrolysis treatment to develop starchy foods with desirable properties.

Gelatinization, pasting, and rheological properties of pea starch in alcohol solution

In this study, we aimed to examine the effects of different low concentrations of alcohol solution (5%–20%) on the gelatinization and pasting properties of pea starch. A rapid visco analyzer revealed that when the starch concentration was fixed, the viscosity of the starch paste decreased with increasing alcohol concentration. In addition, the texture analyzer results showed that compared to the hydrogel formed in water, the hardness of the gel formed by 15% starch in 10% alcohol increased approximately 2-fold (1696.4 g versus 928.1 g). Furthermore, the rheological results showed that the tan δ value of the gel formed under this condition was second only to that of 20% starch in water, which indicated the gel had a strong network structure. X-ray diffraction analysis showed an increased relative crystallinity of 15% starch gels formed in 10% alcohol (13.2%) compared to the hydrogel formed in water (12.2%). Our study will expand the knowledge of the gelatinization properties of starch in low concentrations of alcohol.

Marker-trait association identified candidate starch biosynthesis pathway genes for starch and amylose–lipid complex gelatinization in wheat (Triticum aestivum L.)

During processing of wheat flour, its starch component undergoes gelatinization, an important physicochemical property, affecting cooking and nutrition quality of food products. Genetic loci controlling gelatinization properties of starch and amylose–lipid complex is unknown in wheat. In this study gelatinization properties were measured in a set of 226 wheat varieties using differential scanning calorimetry and their thermograms identified two endothermic peaks: first peak of starch gelatinization and second peak of amylose–lipid complex. The four parameters (onset temp, peak temp, conclusion temp, and enthalpy) of both gelatinization peaks showed wide variation among the varieties. Marker-trait association studies using the genotyping data of 258 SSRs and gelatinization data on the wheat varieties identified 24 and 6 markers associated for starch and amylose–lipid complex gelatinization properties, respectively. Using wheat reference genome sequence and LD decay information, 12 starch biosynthesis pathway genes were identified, which were co-located within 50 Mb of the associated markers. Four out of 12 genes (SSIV, SBEIIb, PHO, and PUL) were located within 5.2 Mb. Out of 24, 17 markers were involved in epistatic interactions. These markers are novel for wheat starch gelatinization properties, and would be useful for gene discovery and marker assisted selection for the improvement of starch quality in wheat.

Starch Components, Starch Properties and Appearance Quality of Opaque Kernels from Rice Mutants.

Rice mutants with altered starch components and properties are important genetic resources in rice breeding programmes. In this study, 44 mutants with altered starch components were screened from 135 rice mutants with opaque kernels using a starch–iodine absorption spectrum method, and nine mutants from them were further selected for investigating their starch properties and kernel appearance quality. The results showed that the iodine absorption spectrum parameters, OD620, OD620/550, and λmax, could reflect the changes of starch components in rice mutants, and had significantly positive relationships with amylose content and negative relationships with the proportion of short branch-chains of amylopectin. The endosperm starches from nine mutants all showed A-type crystalline structure and similar short-range ordered structure, but had different relative crystallinities. The changes of starch components in mutants not only resulted in the different gelatinization properties of starch but also changed the appearance quality of brown rice kernels. This study provided abundant genetic plants for studying the molecular mechanism of starch synthesis and the quality regulation of rice kernels.

Effect of degree of polymerization of amylopectin on the gelatinization properties of jackfruit seed starch

Five gelatinized jackfruit starches (GJFSS: M1′, M5′, M6′, M11′, and BD′) were prepared using amylose mixed with five types of amylopectin. M1′ had the lowest degree of polymerization while BD′ had the highest. The five GJFSS samples showed significant variations in microstructures, varying from a compact structure (M1′) to a loose structure (BD′). The freeze-thaw stability was consistent with results of the microstructure. High syneresis formed compact structure (M1′), and low syneresis formed a loose structure (BD′). As the degree of polymerization of amylopectin increased, the gelatinization enthalpy, peak viscosity, breakdown, final viscosity, setback, and absorbance ratio decreased, while the transition temperature and pasting temperature increased. The thermal, pasting properties, and the short-range molecular order, were consistent with the results of the microstructure and syneresis. All the results indicated that the degree of polymerization of amylopectin is an important structural factor that can significantly affect the gelatinization properties of starch.

The effects of field pre-harvest sprouting on the morphological structure and physicochemical properties of rice (Oryza sativa L.) starch.

This study investigates the effects of field pre-harvest sprouting (PHS) on the morphological structure and physicochemical properties of starches from four rice varieties during the rice harvesting period. The results of the study showed that PHS significantly affected the grain characteristics, starch structure, and physicochemical properties of the four rice varieties. Moreover, PHS led to a significant decrease in the grain processing quality and protein content of the four varieties, pitting and unevenness on the surface of the starch granules, and smaller starch granules. In addition, PHS led to starches with lower amylose content, which resulted in a higher swelling power, solubility, and relative crystallinity. Higher gelatinization enthalpy and lower gelatinization temperature were also observed under PHS conditions. The results indicated that PHS can lead to degradation in grain processing and appearance quality, but it can also lead to some improvements in the gelatinization properties of starch.

Effects of Starch From Five Different Botanical Sources on the Fermentation and Gelatinization Properties of Starch–Gluten Model Doughs

Wheat, corn, tapioca, sweet potato, and potato starches are independently mixed into starch–gluten model doughs containing 15% (w/w) vital gluten. Fermentation properties, including gas production, and retention capacities, are studied by recording dough height and gas release kinetics through rheofermentometer. Gelatinization properties are investigated by recording changes of heat transition and dynamic moduli with temperature using a differential scanning calorimeter and control stress rheometer, respectively. Wheat starch (WS)–gluten dough has the greatest total gas production (500 mL) and gas retention coefficient (87.6%), lowest viscosity, and highest dough structure hardening during gelatinization, while potato starch–gluten dough has the smallest total gas production (85 mL) and gas retention coefficient (82.1%), highest viscosity, and lowest structure hardening during gelatinization. In addition, the ultrastructure and freezable and non‐freezable water contents are determined to investigate the structural properties of the starch–gluten model doughs. WS–gluten dough shows the most consistent and uniform ultrastructure, and highest non‐freezable water content (42.60%) among all the starch–gluten model doughs. This suggests that WS–gluten dough exhibits a better processing performance compares to the other four starch–gluten model doughs.