Starch Paste Viscosity Research Articles

Mapping quantitative trait loci associated with starch paste viscosity attributes by using double haploid populations of rice (Oryza sativa L.)

The paste viscosity attributes of starch, measured by rapid visco analyzer (RVA), are important factors for the evaluation of the cooking and eating qualities of rice in breeding programs. To determine the genetic roots of the paste viscosity attributes of rice grains, quantitative trait loci (QTLs) associated with the paste viscosity attributes were mapped, using a double haploid (DH) population derived from Zhongjiazao 17 (YK17), a super rice variety, crossed with D50, a tropic japonica variety. Fifty-four QTLs, for seven parameters of the RVA profiles, were identified in three planting seasons. The 54 QTLs were located on all of the 12 chromosomes, with a single QTL explaining 5.99 to 47.11% of phenotypic variation. From the QTLs identified, four were repeatedly detected under three environmental conditions and the other four QTLs were repeated under two environments. Most of the QTLs detected for peak viscosity (PKV), trough viscosity (TV), cool paste viscosity (CPV), breakdown viscosity (BDV), setback viscosity (SBV), and peak time (PeT) were located in the interval of RM6775–RM3805 under all three environmental conditions, with the exception of pasting temperature (PaT). For digenic interactions, eight QTLs with six traits were identified for additive×environment interactions in all three planting environments. The epistatic interactions were estimated only for PKV, SBV and PaT. The present study will facilitate further understanding of the genetic architecture of eating and cooking quality (ECQ) in the rice quality improvement program.

Effect of dry heating treatment on multi-levels of structure and physicochemical properties of maize starch: A thermodynamic study

Dry heating treatment (DHT) is a common process widely used in food industry. In this study, the thermodynamic effects of DHT on starch structure and physicochemical properties are investigated. The results show that, with heating temperature increasing during DHT, the molecular size, long-amylose chains with degree of polymerization (DP) ~5000–20,000, and the crystallinity of maize starch are significantly reduced while the granular structure is retained with slightly aggregation between starch particles. The solubility of DHT starch increases from 0.5% to 2%, indicating the majority of DHT starch is still insoluble. DHT affects starch thermal property greatly that, it decreases the gelatinization enthalpy while increases the heterogeneity of starch crystallites. With heating temperature increasing, DHT reduces the overall viscosity of starch paste. The rheological property of DHT starch is frequency-dependent, showing the typical shear thinning behavior and “solid-like” gel property. Especially, as heating temperature reaches 190 °C, the shear resistance becomes stronger, and it is closer to Newtonian fluid. The results prove the thermodynamic effects of DHT on multi-levels of starch structure and physicochemical properties, also indicating the great potential to utilize DHT in modifying starch properties and amplifying its applications.

Rheological and pasting characteristics of wheat starch modified with sequential triple enzymes

To gain desired viscoelastic properties of wheat flour and to expand the wheat flour current utility with more palatable foods, herein wheat starch, one of the important components of wheat flour, has been modified sequentially using β-amylase (BA), transglucosidase (TG) and pullulanase (PUL). The results show that compared to native starch, percentage of shorter linear chains (DP 6-12) significantly increased after the BA→TG→PUL treatment, resulting in lower relative crystallinity but with enhanced ordered structure. Compared to the native starch paste viscosity of 1632.98 Cp, the final viscosity of BA/TG/PUL-modified starch pastes reached the maximum value of 3132.01 Cp when the TG treatment time was 20 h, which indicated the paste viscosity increased by 91.80 %. Furthermore, BA/TG/PUL-modified starch pastes exhibit higher shear resistance and gel strength.

Modification of structural, physicochemical and digestive properties of normal maize starch by thermal treatment

Thermal treatment is an effective technique to modify the physiochemical properties of starch. However, investigation on the effect of repeated dry-heat treatment (RDHT) on the starch properties is limited. In this work, RDHT and continuous dry-heat treatment (CDHT) were conducted on normal maize starch. Both treatments increased pore no on the granule surface and facilitated the granule aggregation. The solubility and swelling power of normal maize starch were improved. The levels of slowly digestible starch (SDS) and resistant starch (RS) + SDS were increased. The structural characteristics, including crystallinity and short-range order, were impaired. The peak viscosity and thermal properties (To, Tp, Tc and ΔH) of starch paste were decreased. When comparing of CDHT samples with the same treating time, RDHT samples showed a lower crystallinity, a weaker thermal stability, a higher paste viscosity and a lower resistance to amylase. These results were useful for industrial application of thermal treatment on starch.

Efficient processing of cassava starch: physicochemical characterization at different processing parameters

The aim of this study was to evaluate the physicochemical properties of cassava starch that was processed using different parameters (types of water, drying temperatures and milling sizes) to be added into the food products as an ingredient. Selected commercial cassava starch was used as a reference. Mineral water showed a significantly higher value (p<0.05) for the paste viscosity of cassava starch compared to the other types of water, but indicated no significant difference (p>0.05) with tap water for the swelling power, solubility and gel strength of cassava starch. The increase in the drying temperature significantly decreased (p<0.05) swelling power, paste viscosity and gel strength of cassava starch but significantly increased (p<0.05) its solubility. The increase in the milling size significantly increased (p<0.05) swelling power and solubility, paste viscosity and gel strength of cassava starch. For industrial benefits, the use of mineral water for starch processing, the lowest drying temperature of 70°C and the largest milling size of 63 μm shall be the best processing parameters to produce cassava starch with the highest swelling power which could act as a reliable expansion aid in food products. These parameters shall also be the best processing parameters to produce cassava starch with the highest paste viscosity which could function as a desirable food thickening or gelling agent, as well as the highest gel strength that could be applied as an excellent texture enhancer, binder, or coating for food products.

Effect of peroxide oxidation on the expansion of potato starch foam

Starch-based foams are drawing increasing interest as bio-sourced alternatives to petroleum-based products when a low-density or air-filled cell structure combined with reasonable mechanical resistance is required. The chemical modification of starch, mainly via oxidation, can improve its expansion capability and, thus, reduce the density of the resulting foam. This study was done to investigate how the oxidation of potato starch with different concentrations of hydrogen peroxide changes its chemical structure. This work provides new insights into how this impacts the paste foaming performance.The intrinsic viscosity of the starch solutions exhibited a linear decrease as the degree of oxidation increased, indicating that the molecular weight of the starch is reduced by oxidation because of chain scission. FTIR (and second derivative) analysis revealed the decrease in the number of CH and CO bonds caused by the conversion of CH2OH-6 into carboxyl groups in the oxidation reaction. In addition, NMR measurements showed a reduction in the signal assigned to the OH-6 hydroxyl groups, confirming their transformation into carboxyl groups. The densities of the foams prepared with the modified starches decreased as the oxidant concentration increased, from 308 kg/m3 for native starch (NS) to 142 kg/m3 for starch oxidized with 25% H2O2 (OS25). However, the starch prepared with the highest peroxide concentration showed a high density of 258 kg/m3 (OS70). The dependence of the starch paste viscosity on the oxidant concentration, which results from a balance between the decrease in molecular weight and the increase in attractive chain interactions, was analyzed and an adequate interpretation for this behavior was provided. The internal bond strength of the foams exhibited the same trend as the density as a function of oxidant concentration (from 0.641 in NS to 0.439 in OS25) as expected because a lower density implies less mechanical cohesion within the foam.

Relationship between sorption characteristic and selected functional properties of chemically modified waxy maize starches

The aims of this study were to evaluate the effect of chemical modification of waxy maize starch on its sorption, pasting properties, and in vitro digestibility, and to investigate the relationships among tested properties. The research materials were octenyl succinate, acetylated, oxidized, and acetylated-oxidized starches. Starch acetylation and octenyl succinylation decreased amount of moisture content adsorbed above 0.4 water activity. For all tested starches, the bound adsorption predominates over free adsorption. Esterification with octenyl succinic or acetic anhydrides increased pastes hot paste and final viscosities. The rapidly digestible starch content decreased after performed modifications of waxy maize starch. Correlation analysis showed that peak viscosity and breakdown parameter of starch pastes were largely dependent on the properties of sorbed water. Ratio of free to bound water (F/B) at different water activities correlated with the setback values and contents of slowly digestible and resistant starch fractions. Practical applications Generally, both sorption and functional properties of starch are modified in order to functionalize the polymer to meet specific requirements in the areas of food production and preservation. The research was aimed not only to investigate the sorption and functional properties of chemically modified starches, but also to find a relationships between the obtained results. Knowledge of these relationships can be used to formulate composition of food product, optimize processing parameters and select proper storage conditions to prevent product failure. On the basis of obtained results it was revealed that octenyl succinate and acetylated-oxidized waxy maize starches exhibited lower amount of moisture content adsorbed at aw < 0.4. Therefore, these starches may be useful for processing and storing of low-moisture starchy foods. Moreover starches with lower water absorbability form more stable gels. Obtained findings may be an useful tool for estimating the functional properties and the critical moisture contents during starchy food storage, that can assist to improve shelf-life of stored products.

ВЛИЯНИЕ ЭФФЕКТОВ УЛЬТРАЗВУКА НА РЕОЛОГИЧЕСКИЕ СВОЙСТВА КЛЕЙСТЕРОВ КАРТОФЕЛЬНОГО КРАХМАЛА

To improve the technological characteristics of starches, which are used in the food industry, viscosity control is one of the most promising areas that should be considered, since starch is primarily used as a natural thickener and emulsifier. At temperatures of 58–65 °С and above, the process of potato starch gelatinization occurs with the subsequent formation of hydrogels. Ultrasound can effectively reduce the viscosity of starch solutions after gelatinization. The advantages of ultrasound exposure are the following: the process does not require the use of any chemicals and additives; the process can be simple and fast; the process does not cause major changes in the chemical structure of starches but only affects its rheological properties. The effectiveness of ultrasound exposure was evaluated by measuring the changes in viscosity and emulsifying ability of starch paste. The change in the molecular weight of starch, and hence the emulsifying ability, was monitored by an SF-56 spectrophotometer. Ultrasound exposure can be applied to many types of starch (corn, tapioca, wheat, etc.), our research is aimed at potato starch, due to the fact that the Ural region is a favourable area for the cultivation of potatoes, including as a source of starch. The results obtained suggest a decrease in the viscosity of potato starch paste after gelatinization under the influence of ultrasound. Emulsifying activity in samples treated with ultrasound is 2–3 times higher, is evidence that physical and chemical parameters change, namely the structure and size of starch grains, which leads to an increase in their homogeneity, a decrease in molecular weight and an increase in the ability to form lower molecular units.

Impact of the degree of octenyl succinylation on metal ions complexation and functional properties of maize starch.

Modified maize starches were obtained by the esterification of native starch with octenyl succinic anhydride (OSA) at levels of 3% or 9%, and afterwards by its complexation with metal ions. The degree of substitution, contents of metal ions, hydrodynamic size distribution, intrinsic viscosity, pasting characteristics of the tested starches, and pastes surface tension were determined. Moreover, emulsions prepared from the modified starches were studied for oil droplet size distribution and storage stability. Reduction of hydrodynamic size and intrinsic viscosity was observed in octentyl succinate starch (OS starch) esterified with 3% OSA complexed with magnesium or calcium. The presence of potassium in both esterified starches increased their water binding capacity and solubility in water. In most cases, complexation with metal ions decreased viscosity of OS starch pastes. Emulsions prepared from the modified starches had smaller oil droplets and were more stable during storage, compared to the systems prepared from non-esterified starch.

Исследование процесса получения амилопектинового фосфатного крахмала

Увеличение объемов производства модифицированных крахмалов, расширение их ассортимента на основе использования зернового и клубневого крахмалов, повышение импортозамещения являются актуальными задачами для крахмалопаточной отрасли. Одно из основных направлений повышения импортозамещения модифицированных крахмалов - разработка и внедрение на предприятиях отрасли новых технологий по производству крахмалофосфатов с повышенной вязкостью и стабильностью крахмальных клейстеров при механическом воздействии.&#x0D; Исследовано влияние различных технологических факторов на изменение физико-химических свойств нативного амилопектинового крахмала при его экструзионной обработке в присутствии фосфоросодержащих реагентов. В качестве реагентов использовали триполифосфат натрия и гексаметафосфат натрия. Изучено влияние расхода реагентов, температуры обработки крахмала, частоты вращения шнеков на физико-химические свойства амилопектинового фосфатного крахмала. Определено, что наибольшую динамическую вязкость и водосвязывающую способность имели образцы амилопектинового фосфатного крахмала, полученные при температуре обработки крахмала 160…170 оС и применении двух реагентов: триполифосфата натрия и гексаметафосфата натрия, расход которых составлял по 1,0 % к массе сухих веществ крахмала. Проведены исследования по изучению влияния частоты вращения шнеков на свойства амилопектинового фосфатного крахмала. Рекомендована оптимальная частота вращения шнеков для получения высококачественного продукта. Показано, что дисперсии амилопектинового фосфатного крахмала устойчивы к механическим воздействиям (перемешиванию). Результаты исследований служат основой для разработки нормативной документации и внедрения технологии на предприятиях крахмалопаточной отрасли с целью увеличения объема выпуска модифицированных крахмалов отечественного производства и расширения их ассортимента.

Effects of Pectin on the Pasting, Rheological, and Textural Properties of Lotus Root Starch

To determine the effects of hydrocolloids on starch properties, high‐methoxyl pectin (HMP), and low‐methoxyl pectin (LMP) are mixed with lotus root starch (LRS). Changes in pasting, rheological, and textural properties, and microstructure of LRS composites are analyzed. LMP increases final viscosity, peak viscosity, breakdown viscosity, retrogradation value, and peak time of starch paste. HMP increases the peak time, but it decreases all other four pasting parameters. LMP increases shearing stress of LRS paste. The shearing stress of LRS paste is proportional to LMP concentration. With increasing consistency coefficient K, the flow behavior index n decreases. Opposite results are observed in HMP. In the LRS/HMP and LRS/LMP, G′ and G″ are positively correlated with LMP content, but these are negatively correlated with HMP. The minimum tanδ is achieved when LRS:LMP = 8:2, thereby indicating the strongest elasticity features. HMP can well inhibit short‐term retrogradation of LRS. Pectin decreases LRS hardness but increases cohesiveness, thereby forming a softer gel. Variations of adhesiveness and springiness are related with pectin type. According to SEM observation, the involvement of LMP destroys the original structure of LRS and forms a stable network structure, which is rare in the LRS/HMP system.

Towards a genetic road map of wheat-processing quality

The elucidation of wheat-quality genetics may be seen metaphorically as a road map to greater knowledge, and also as an interlocking jigsaw puzzle. Major genes relevant to the attributes needed for wheat-processing quality have been identified, namely, protein content, grain hardness, milling yield, dough strength, dough extensibility, baking quality, starch-paste viscosity and nutritional value.

Retrogradation, gel texture properties, intrinsic viscosity and degradation mechanism of potato starch paste under ultrasonic irradiation

The effects of sonication on the retrogradation, gel texture properties, intrinsic viscosity and degradation of potato starch paste (PSP) were investigated using a specially designed reactor to study changes in molecular structure and functional properties. The retrogradation was analyzed by an x-ray diffractometry. The gel texture properties were analyzed by texture profile analysis (TPA) and the intrinsic viscosity was analyzed using a Cannon-Ubbelohde viscometer at different sonication times, intensities and PSP concentrations. The molecular weight of PSP was determined using gel permeation chromatography (GPC). The results showed that retrogradation of PSP occurred when it was placed in a high density ultrasonic field, and was accompanied by a transition from crystalline type B to type VH. The TPA results indicated remarkable decreases in gel texture properties (hardness, fracture ability, adhesiveness, gumminess, and chewiness) when the sonication time was prolonged, the intensity was increased and when the PSP concentration was reduced. Intrinsic viscosity decreased with extended sonication time and at higher intensity, but increased as the PSP concentration increased. The GPC results showed that the average molecular weight of PSP decreased significantly upon ultrasonic irradiation and the sample had a narrower distribution of molecular weight. The degradation kinetics were adequately described by the Baramboim models. Radical trapping by 2,2-diphenylpicrylhydrazyl was used to assess the radical-attack mechanism in PSP subjected to ultrasound. Under the reaction conditions, degradation of PSP in the ultrasound field is caused by OH radicals and mechanochemical effects. Mechanochemical effects were the main cause of bond scission.

Mapping quantitative trait loci associated with starch paste viscosity in rice (Oryza sativa L.) under different environmental conditions

AbstractA recombinant inbred line (RIL) population consisting of 153 lines derived from a cross between indica ‘Zhongyouzao8’ and japonica ‘Toyonishiki’ rice was used to detect stable quantitative trait loci (QTL) for rapid visco analyser (RVA) characteristics under four environmental conditions. We identified 93 QTL for RVA profiles, and four pleiotropic regions harbouring stably expressed QTL were detected on chromosomes 2, 6, 7 and 11. These newly identified and stable QTL will facilitate further research into the genetic mechanism regulating RVA profiles. Amylose content (AC) was correlated with RVA traits. AC and RVA traits were unaffected by indica–japonica subspecies differentiation, suggesting that RVA profiles were mainly influenced by the Wx gene. The RIL population was divided into two subpopulations according to Wx genotypes. A total of 106 QTL associated with RVA profiles were detected in the subpopulations. These QTL differed from those detected in the whole population in terms of their genomic location, number, logarithm of odds values and amount of phenotypic variance explained. Using this strategy, we detected QTL with minor effects and eliminated false due to the Wx gene.

Structural and physicochemical properties of granular starches after treatment with debranching enzyme

The present study modified maize and potato granular starches by partial debranching treatment below the gelatinization temperature, and investigated their structural and physicochemical properties. Pullulanase was much effective (more than three times) on hydrolyzing potato starch compared to maize starch as measured from total carbohydrate values in the supernatant. The pullulanase hydrolysis decreased the amount of double helices as observed from DSC measurement. These effects were dependent upon the time of enzyme hydrolysis (24h>8h>1h) as well as type of starch (potato>maize). The pullulanase hydrolysis decreased the peak viscosity of the potato starch paste, whereas the effect was very less pronounced for maize starch. The current results showed that it is possible to achieve the starches with desired physicochemical properties by varying the starch type as well as modification process.

Genetic dissection of starch paste viscosity characteristics in waxy maize revealed by high-density SNPs in a recombinant inbred line population

Starch paste viscosity properties are widely used as important indicators for quality estimation in waxy maize. To elucidate the genetic basis of paste viscosity characteristics of waxy maize, seven parameters from the rapid visco analyzer (RVA) profile were analyzed for quantitative trait loci (QTLs) in this study, using a recombinant inbred line population derived from a cross between the inbred lines Tongxi5 and Hengbai522. A high-density linkage map was constructed using 2703 bin markers, covering 1876.20 cM of the whole genome with an average genetic distance of 0.73 cM between adjacent bin markers. Seventy-two QTLs were detected for RVA parameters across 3 years, of which 17 could be identified in 2 years, and 6 identified in all 3 years. Eight QTL clusters were observed to be co-associated with two or more RVA parameters. Three major QTLs, qPV4-1, qTV4-1, and qFV5-2, which explained over 10% of the phenotypic variation, were stably mapped to the chromosomes 4 or 5 in all years. Based on functional annotations, two genes were considered as potential candidate genes for the identified major QTLs. The QTLs and candidate genes identified in this study will be useful for further understanding of the genetic architecture of starch paste viscosity characteristics in waxy maize, and may facilitate molecular breeding for grain quality improvement in breeding programs, and simultaneously provide a basis for cloning of the genes underlying these QTLs.

Properties of corn starch subjected hydrothermal modification

Abstract The objective of this study was to determine the effect of heating a water dispersion of corn starch to various temperatures, followed by its freezing and defrosting, on selected properties of re-formed starch pastes. A suspension of starch was heated to various temperatures ranging from 59 to 94°C, and afterwards frozen and defrosted. The differential scanning calorimetry (Mettler Toledo, 822E) thermal characteristics of starch pre-heated to temperatures not inducing complete pasting revealed transitions of: (I) retrograded amylopectin, (II) non-pasted starch, (III) amylose-lipid complexes, (IV) retrograded amylose, and (V) highly thermostable starch structures. The application of higher temperatures during heating caused disappearance of transitions II and V. The increase of pre-heating temperature induced firstly a decrease and then stabilization of the swelling power as well as a successive decrease in starch solubility. Pastes pre-heated to temperatures over 79°C contained large macroparticles that were increasing viscosity of the re-formed starch paste (their size was positively correlated with viscosity value).

Genome-wide association study of eating and cooking qualities in different subpopulations of rice (Oryza sativa L.).

BackgroundStarch and protein are two major components of polished rice, and the amylose and protein contents affect eating and cooking qualities (ECQs). In the present study, genome-wide association study with high-quality re-sequencing data was performed for 10 ECQs in a panel of 227 non-glutinous rice accessions and four derived panels.ResultsPopulation structure accounted for high phenotypic variation in three routine panels and had minor effects on subspecies-based panels. Using the mixed linear model method based on the P + K model, we detected 29, 24, 16, 17, and 29 loci that were significant for ECQ parameters in each of the five panels. Some of these loci were close to starch synthesis-related genes. Two quantitative trait loci (QTLs) (chr.9: 15417525 ~ 15474876; 17538294 ~ 18443016) for several starch paste viscosity properties detected in four panels were close to the isoamylase 3 gene, one QTL (chr.1: 30627943 ~ 31668474) for consistency detected in three panels was close to the starch synthase IV-1 gene. The QTL (chr.7: 1118122 ~ 1967247) for breakdown (BD), detected in the whole panel and japonica panel, and one QTL (chr.7: 25312126 ~ 26540950) for BD and setback (SB), detected in the whole panel and indica panel, may be specific gene alleles in japonica or indica panels. One previously detected QTL (chr.11: 22240707 ~ 22563596) for protein content and one new QTL (chr.5: 7756614 ~ 8042699) for many ECQ traits detected in more than two panels, may represent valuable targets for future cloning of the underlying genes.ConclusionsThis study detected minor-effect QTLs affecting ECQs, and may increase our understanding of the genetic differences regulating the formation of ECQ between indica and japonica varieties.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-3000-z) contains supplementary material, which is available to authorized users.

Annealing improves paste viscosity and stability of starch

The effect of annealing treatments at different temperatures on structural and functional properties of wheat, potato, and yam starches was investigated. Annealing had little effect on the long- and short-range ordered structures of three starches, except for the annealing of wheat starch at 50 °C. Annealing increased the gelatinization temperatures of three starches, but had little effect on the enthalpy changes. Annealing at 30 and 40 °C increased the overall paste viscosity of wheat starch, while the treatment at 50 °C reduced the paste viscosity substantially. There was a continuous increase in paste viscosity of potato starch after annealing at 50 °C during the whole RVA (rapid viscosity analyser) testing. The increases in gelatinization temperatures and paste viscosities were attributed to the increased ordering of starch chains in amorphous regions. Our results showed that annealing is an effective method to increase the paste viscosity of starch, which is very important for the application of annealed starch.

Physicochemical, morphological, thermal and pasting properties of marama (Tylosema esculentum) storage root starch

Starch from marama (Tylosema esculentum) storage roots were isolated and characterized for physicochemical, micro‐ and molecular structure, pasting, and thermal properties, and were compared to commercial cassava, maize, and potato starches. The amylose content of marama root starch was 192 g/kg starch; and was close to cassava (196 g/kg), but lower in comparison to maize (250 g/kg) and higher than potato (161 g/kg). Marama root starch granules were found to be simple; spherical, lenticular, and oval in shape with granule size range of about 5–38 µm. The peak viscosity (5350–5475 mPa · s) of marama root starch paste is about twice as high as those of cassava and maize. Marama root starch has higher gel firmness than cassava but half that of potato and maize starches. Gelatinization temperature range (67.5–79.0°C) of marama root starch was close to commercial cassava and maize starches. Marama root starch exhibited type A molecular arrangement (X‐ray diffraction) pattern similar to the cassava and maize starches, but different to type B exhibited by the potato starch. Granule size, amylose:amylopectin ratio and molecular arrangement pattern seem to account for the differences and or similarities between marama root starch and the commercial starches. Marama starch has potential as thickeners in food compared to maize and cassava due to the high viscosity.