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1.
Food Chem ; 358: 129858, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933983

RESUMO

The effect of sonication temperature on the structures and digestion behaviour of corn starch (CS, A-type), potato starch (PtS, B-type), and pea starch (PS, C-type) was investigated. For CS, sonication temperature resulted in a rough surface, decreased apparent amylose content, gelatinization enthalpy and gelatinization degree, increased short-range orders, long-range orders, retrogradation degree and resistant starch content. For PtS, sonication temperature led to a coarser surface with scratches, increased apparent amylose content and gelatinization degree, decreased short-range orders, long-range orders, gelatinization enthalpy, retrogradation degree, and resistant starch content. For PS, sonication temperature showed partial disintegration on surface, increased gelatinization degree, decreased apparent amylose content, short-range orders, long-range orders, gelatinization enthalpy, retrogradation degree and resistant starch content. This study suggested that starch digestion features could be controlled by the crystalline pattern of starch used and the extent of sonication temperature, and thus were of value for rational control of starch digestion features.


Assuntos
Ervilhas/química , Solanum tuberosum/química , Amido/química , Amido/farmacocinética , Zea mays/química , Amilose/análise , Amilose/química , Digestão , Gelatina/química , Sonicação , Temperatura
2.
Food Chem ; 355: 129660, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33799246

RESUMO

For Pickering emulsifying effect, starch must be subjected to the pretreatments of acid hydrolysis, esterification, which are complicated and eco-unfriendly. In this study, a practical and green strategyto fabricate Pickering emulsion gels with dihydromyricetin (DMY)/high-amylose corn starch (HCS) composite particles was introduced for the first time. The DMY content in composite particles and the amount of addition of composite particles had obvious synergistic effect on the formation and properties of emulsion gels. The obtained emulsion gels were not sensitive to ionic strength, which could be attributed to emulsifying capacity and viscosity effect of composite particles. The spectral analysis confirmed the presence of DMY/amylose host-guest supramolecules. The molecular simulation of the supramolecular complexes in the oil-water system indicated that these complexes could spontaneously aggregate and anchor to the oil-water interface, reducing the interfacial tension. Based on experimental and theoretical results, the multi-scale relationship of "molecular interaction-particle characteristics-gel properties" was established.


Assuntos
Amilose/análise , Flavonóis/química , Amido/química , Emulsões , Géis , Concentração Osmolar , Viscosidade
3.
J Food Sci ; 86(5): 1819-1834, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33890302

RESUMO

Sweetpotato French fry (SPFF) textures have been associated with dry matter and starch contents, but these do not fully account for all textural differences. This study investigated the relationships between the physicochemical properties of sweetpotato starch and textural attributes of sweetpotato fries. Starches from 16 sweetpotato genotypes that varied in dry matter content were isolated and analyzed. The amylose content, pasting temperatures and viscosities, and textural properties of equilibrated starch gels were measured. Correlational analysis was performed with the respective SPFF mechanical and sensory texture attributes. Sweetpotato starch amylose content ranged from 17.3% to 21.1%, and the pasting and gel textural properties varied significantly between starches. Starch from orange-fleshed sweetpotatoes had lower pasting temperatures than starches from yellow/cream-fleshed genotypes, 72.2 ± 2.0 and 75.5 ± 1.1 °C, respectively. Notable inverse correlations were observed between the starch pasting temperature and perceived moistness (r = -0.63) and fibrousness (r = -0.70) of fries, whereas SPFF denseness was positively associated with starch pasting viscosity (r = 0.60) and nonstarch alcohol-insoluble solids content. Fry textures were likely affected by cooked starch properties, which should be considered when selecting varieties for sweetpotato fries. PRACTICAL APPLICATION: Without the aid of a batter, sweetpotato French fries (SPFFs) tend to be soft and limp-undesirable attributes in a fried food. The physiochemical properties of starch, the most abundant component in sweetpotato fries, were further explored in this study to better understand the properties of sweetpotato starch that influence SPFF textures. These findings can be used by sweetpotato processors and breeders for developing new sweetpotato varieties that are designed for production of fried products with desirable textures.


Assuntos
Culinária/métodos , Ipomoea batatas/química , Amido/química , Amilose/análise , Fenômenos Químicos , Tubérculos/química , Sensação , Temperatura , Viscosidade
4.
Food Chem ; 354: 129434, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33756327

RESUMO

Analytical algorithms based on Raman spectroscopy are proposed for the determination of amylopectin and amylose concentrations in polished white rice, and applied to characterize and compare linear and branched polysaccharide structures in nine different types of Japanese rice. A selected algorithm used symmetric bending vibrations of the COC glycosidic linkage from a relatively narrow spectral zone between 830 and 895 cm-1. It specifically compared the intensity of Raman signals from two types of bending common to both starch components (C1-O-C5 and C1-O-C4 at 868 and 855 cm-1, respectively) and that at the branch point peculiar to amylopectin (C1-O-C6 at 844 cm-1). Raman data were confronted with data collected by conventional amylose-iodine colorimetry method. Consistency was found between Raman and colorimetric methods over the entire series of tested rice cultivars, thus validating the newly proposed spectroscopic algorithm. The amylose content of the tested rice species broadly varied between 1.2 and 20.4%. The proposed Raman algorithm allows fast and nondestructive determination of amylose content in rice with minimal sample preparation. These characteristics might be key in the development of portable Raman devices capable to promptly screen polysaccharides in different rice cultivars with respect to their interannual and plantation-related fluctuations.


Assuntos
Amilose/análise , Oryza/metabolismo , Algoritmos , Amilopectina/química , Colorimetria , Iodo/química , Japão , Análise Espectral Raman , Amido/química
5.
Food Chem ; 349: 129176, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592575

RESUMO

Yield, taste quality, and cultivar utilisation improvements are important research topics in indica rice breeding. Herein, we compared the relative effectiveness and relationship of three taste evaluation methods, namely, chemical composition, Rapid Visco Analyser (RVA), and taste analyser. We assessed associations among these methods using 36 indica varieties commonly grown in Yunnan, Sichuan, and Guizhou, China. Temperature and sunlight duration during grain filling influenced rice cooking quality. Varieties with high taste quality had low amylose and protein contents; high peak viscosities and breakdowns; and low hold viscosities, setbacks, and final viscosities. Protein and combined protein and amylose explained 38.6% and 62.1% of the variation in taste value, respectively. The RVA profile was affected by protein, amylose, and amylopectin contents and explained 60.5% of the taste-value variation. This study lays the foundation for taste evaluation of high-quality rice varieties early in the breeding process, which can improve cultivation and marketing potential.


Assuntos
Análise de Alimentos/métodos , Oryza/química , Paladar , Amilopectina/análise , Amilose/análise , Culinária , Oryza/classificação , Oryza/crescimento & desenvolvimento , Temperatura , Fatores de Tempo , Viscosidade
6.
J Food Sci ; 86(3): 907-914, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33624319

RESUMO

Ten native potato varieties grown in Cusco (at 3,672 m above sea level) were used for starches extraction (at a pilot scale), and their physicochemical, functional, morphological, and structural characteristics were assessed. The content of protein, apparent amylose and phosphorus ranged from 0.1% to 0.44%, 23.42% to 35.5%, and 0.07 to 0.10%, respectively. Starch granules revealed smooth surface, with ellipsoidal and spherical shapes, particle size analysis exhibited bimodal or multimodal distribution, while the averaged crystallinity was 27.7% assessed by XRD. Gelatinization temperatures of the starches ranged from 57.4 to 60.1 °C, 60.8 to 64.3 °C, and 68.4 to 71.1°C for To, Tp, and Tc, respectively; and the gelatinization enthalpies ranged from 15.4 to 17.1 J/g. Respect to pasting properties, the peak viscosity and setback viscosity ranged from 12,970 to 16,970 mPa⋅s and from 968 to 2498 mPa⋅s, respectively. Thermogravimetric analysis (TGA) revealed no significant relationship between apparent amylose content and thermal stability. Therefore, the results reveal subtle differences in the functional characteristics of the starches from the native varieties of potato studied, which can be recommended for food industry applications. PRACTICAL APPLICATION: This study contributes to show several varieties of native potatoes from Cusco and their valorization as nonconventional starch source. Describing the physicochemical, functional, and structural characteristics of these starches could be useful for food industry applications.


Assuntos
Solanum tuberosum/química , Amido/análise , Amilose/análise , Amilose/química , Fenômenos Químicos , Estabilidade de Medicamentos , Géis/química , Peru , Tubérculos/química , Solanum tuberosum/crescimento & desenvolvimento , Amido/química , Temperatura , Termodinâmica , Viscosidade
7.
Food Chem ; 347: 129045, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33486361

RESUMO

The effects of water irrigation management including conventional irrigation (CK), constant flooding irrigation (CFI) and alternate wetting and drying (AWD) on starch structure and physicochemical properties of two indica rice cultivars with good- and poor-quality were evaluated in the field condition with two years. The results showed that AWD could significantly increase peak viscosity, breakdown and gelatinization temperature, decreased setback and gelatinization enthalpy in two indica rice cultivars. However, starch granule size and amylopectin chain length distribution were differed the trends in the rice cultivars and treatments. AWD reduced starch granules size and amylopectin short chain, especially for large starch granules, but increased medium and long chain, which might contribute to better thermal stability and pasting viscosity for good-quality cultivar. Our study indicated that water irrigation management affected starch structure and physicochemical properties of indica rice starch, and would provide favorable information for improvement of rice starch in food industry.


Assuntos
Oryza/química , Amido/química , Água/química , Amilopectina/química , Amilose/análise , Varredura Diferencial de Calorimetria , Oryza/metabolismo , Tamanho da Partícula , Proteínas de Plantas/análise , Temperatura , Viscosidade , Água/metabolismo
8.
Int J Biol Macromol ; 172: 439-451, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33453260

RESUMO

The aim of this research work was to investigate novel tools given by nanotechnology and green chemistry for improving the disadvantages typically associated to the starch-based films: water susceptibility and brittle mechanical behavior. With this in mind, four food packaging film systems were developed from corn starch or corn starch nanocrystals (SNCs), and modified by phosphating under reactive extrusion (REx) conditions using sodium tripolyphosphate (Na5P3O10 - TPP) as a crosslinker. The structural, physicochemical, thermal, rheological and mechanical properties, as well as studies associated with the management of carbohydrate polymer-based plastic wastes (biodegradability and compostability) were carried out in this study. The hierarchical structure and the modification of the starch were dependent on the amylose content and degree of substitution (DS), which in turn depended on the hydrogen (H)-bonding interactions. In both cases, a higher molecular ordering of the starch chains in parallel was decisive to obtain the self-assembled thermoplastic starches. Beyond the valuable results obtained and scientifically analyzed, unfortunately none of the manufactured materials achieved to improve their performance compared to the control film (thermoplastic starch - TPS). It was even thought that the phosphated starch-based films could fertilize lettuce (Lactuca sativa) seedlings during their biodegradation, and this was not achieved either. This possibly due to the low content of phosphorus or its poor bioavailability.


Assuntos
Embalagem de Alimentos/métodos , Nanopartículas/química , Polifosfatos/química , Amido/química , Amilose/análise , Humanos , Ligação de Hidrogênio , Membranas Artificiais , Nanopartículas/ultraestrutura , Fosforilação , Amido/isolamento & purificação , Zea mays/química
9.
Int J Biol Macromol ; 172: 341-349, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33465359

RESUMO

The protein corona on nano drug carriers is an important well-known biological issue that often induce biological incompatibility and screens the targeting molecules on the surfaces of carriers, therefore, the design of NPs with good protein corona-free property is highly desired and challenged. The natural polysaccharide has been demonstrated as one types of stealth materials after the functional group modification process, but the types and structures of their chains has never been considered. Here, we have designed five types of core-shell starch-coated poly (methyl methacrylate) nanoparticles and we found the starch coated NPs with low amylose content (<15%) could exhibit the excellent protein corona-free property without any modification and the starch with high amylose content coated NPs can also exhibit protein corona-free property after etherifying the surface of NPs to positive surface charge. Therefore, the combined impact of both low amylose content and positive surface charges by etherification modification of the starch can provide the excellent protein corona-free property for starch coated polymer NPs, that is very promising for highly efficient nano drug carries and marine coatings.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Polimetil Metacrilato/química , Amido/química , Amilose/análise , Nanopartículas/ultraestrutura , Coroa de Proteína/análise , Coroa de Proteína/química , Soluções , Eletricidade Estática
10.
Carbohydr Polym ; 255: 117503, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436256

RESUMO

To determine the internal structure of barley starch without amylopectin isolation, whole starch was hydrolyzed using ß-amylase to remove the linear amylose and obtain ß-limit dextrins (ß-LDs). The ß-LDs were treated with extensive α-amylase to prepare α-limit dextrins (α-LDs), and the α-LDs were further hydrolyzed with ß-amylase into building blocks. The chain-length distribution of ß-LD and building block composition were analyzed by size-exclusion chromatography and anion-exchange chromatography. The internal structure of the barley whole starches had similar pattern to barley amylopectins analyzed by conventional methods. The starch of barley amo1-mutated varieties contained more short internal B-chains and less long internal B-chains than that of other varieties. The starch from amo1-mutated varieties had more large building blocks than that from waxy varieties. The simplified method presented in this study can effectively characterize starch internal structure that relates to physicochemical properties of starch, although some details of amylopectin structure are not assessable.


Assuntos
Amilopectina/análise , Amilose/análise , Dextrinas/análise , Amido/química , alfa-Amilases/química , beta-Amilase/química , Amilopectina/química , Amilose/química , Sequência de Carboidratos , Cromatografia em Gel , Cromatografia por Troca Iônica , Dextrinas/química , Hordeum/química , Humanos , Hidrólise
11.
Food Chem ; 337: 127784, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795860

RESUMO

Variation in salt content and in pH are common in starch-based foods and can affect starch properties and final product texture. Fifteen accessions of proso millet starch with diverse amylose content were selected to investigate single factor and interaction effects of pH and NaCl on thermal, pasting, and textural properties. Pasting properties and gelatinization temperatures were markedly altered by salt addition. Changes in pH only had substantial effects on ΔH, but other properties were generally stable under different pH conditions. From two-way ANOVA, interactive effects of salt and pH were found to affect ΔH. The response of starch of different genotypes in terms of thermal and pasting properties differed under the same pH and salinity conditions. The reason is likely that ions in the starch-water system performed the roles of both reducing water activity and building of hydrogen bonds, which will have opposite effects on starch gelatinization.


Assuntos
Genótipo , Panicum/química , Amido/química , Amilose/análise , Amilose/química , Amilose/genética , Concentração de Íons de Hidrogênio , Panicum/genética , Cloreto de Sódio , Temperatura
12.
Food Chem ; 339: 127917, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32950898

RESUMO

Andean beans (Phaseolus vulgaris) chemical compositions and cooking characteristics contribute to a healthy diet. The objective of this study was to evaluate the influence of chemical composition on the cooking quality of 14 Andean beans genotypes with different seed coat colors. More specifically, water retention (WR), cooking time (CT), and solids released in the broth, were analysed. WR values ranged from 128.4% to 160.7% and CT ranged from 13.7 (BRS Embaixador) to 21.7 min (KID44). Andean beans showed variability in chemical composition, mainly starch content (39.43 g 100 g-1, BRS Realce to 51.92 g 100 g-1, LP15-04) and polymer composition. The profile of starch and interactions among minerals and chemical compounds influenced the cooking profiles than do the individual compounds. Andean beans traits of cooking, mainly CT, were influenced by their chemical composition; however they can be incorporated into diets without drastic changes in preparation methods.


Assuntos
Culinária/métodos , Phaseolus/química , Amido/análise , Amilopectina/análise , Amilose/análise , Genótipo , Minerais/análise , Análise Multivariada , Phaseolus/genética , Phaseolus/metabolismo , Sementes/química , Sementes/genética , Sementes/metabolismo
13.
Food Chem ; 336: 127716, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32768910

RESUMO

Jackfruit seed starch (JFSS) was modified by an improved extrusion cooking technology (IECT), and the supramolecular structure, molecular weight, debranched chain length distributions, relative crystallinity (Rc), and amylose content, were studied. During IECT, the α-1.4-glycosidic bond in amylopectin was broken, which led to decreased radius of gyration (Rg), number-average molar mass (Mn), weight-average molar mass (Mw), long chains and Rc. The medium and short chains and PI (Mw/Mn) increased, while the amylose content hardly changed. The crystalline structure of JFSS was converted from A-type to V-type. Increasing the temperature and screw speed during the treatment significantly increased the medium and short chains and Rg, while it decreased the long chains, amylose, Mn, Mw, PI, and Rc. However, the opposite effect was observed when increasing the moisture content. The in vitro digestibility of JFSS was significantly improved after IECT, due to destruction of starch supramolecular structure according to principal component analysis.


Assuntos
Artocarpus/química , Sementes/química , Amido/química , Amilopectina/química , Amilose/análise , Amilose/química , Culinária/métodos , Digestão , Peso Molecular , Análise de Componente Principal , Temperatura
14.
Carbohydr Polym ; 251: 117046, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142604

RESUMO

Here, we present a gold nanoparticle-based colorimetric assay for the determination of molecular weight distribution and branching characteristics of enzymatically hydrolyzed starch. The steric stabilization effect of starch hydrolysate on the colloidal stability of AuNPs was found to be proportional to the ratio of high molecular weight amylopectins, which was clearly reflected by the intensity of the characteristic surface plasmonic resonance (SPR) absorbance peak of the AuNPs. The fractional change of high molecular weight amylopectin over the course of enzymatic hydrolysis reaction could be measured based on the intensity of SPR peak, in which the results correlated well with those obtained by conventional gel permeation chromatography. With the proper calibration of a specific set of enzyme and starch type, this method would provide a fairly simple and fast means of analyzing the molecular weight distribution of starch hydrolysate on site as well as the amylose content in native starch.


Assuntos
Amilopectina/análise , Amilose/análise , Colorimetria/métodos , Enzimas/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Amido/química , Hidrólise , Peso Molecular , Amido/metabolismo , Ressonância de Plasmônio de Superfície
15.
Food Chem ; 330: 127328, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569940

RESUMO

Granular protein is an important structural feature in determining starch digestibility. High-amylose wheat starch (HAWS) with >80% amylose content contains more granular protein than wild-type starch. As analyzed by mass spectrometry-based proteomics, granular-bound starch synthase (GBSS) is the major granular protein in isolated starch materials. GBSS content increases with amylose content (Spearman's correlation, p < 0.05), whereas the abundance relative to other proteins is similar among starches. Multiple amylase inhibitors were also identified. From Michaelis-Menten analysis, HAWS has a similar Km (Michaelis constant) as wild type, suggesting initial enzymatic binding is similar. After the pre-digestion of proteins, wild type had a greater change in starch digestibility than HAWS, probably due to the latter having 'thicker' granular-protein layers and higher enzymatic resistance of substrate per se. Overall, the study suggests that the greater granular protein content in HAWS is a factor that contributes to slower amylolysis compared to wild type.


Assuntos
Amilose/metabolismo , Proteínas de Plantas/metabolismo , Sintase do Amido/metabolismo , Amido/química , Triticum/química , Amilose/análise , Amilose/química , Digestão , Hidrólise , Cinética , Proteínas de Plantas/análise , Amido/metabolismo , Sintase do Amido/análise , Espectrometria de Massas em Tandem , Triticum/metabolismo , alfa-Amilases/química , alfa-Amilases/metabolismo
16.
PLoS One ; 15(6): e0234395, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525930

RESUMO

As rice is an important staple food globally, research for development and enhancement of its nutritional value it is an imperative task. Identification of nutrient enriched rice germplasm and exploiting them for breeding programme is the easiest way to develop better quality rice. In this study, we analyzed 113 aromatic rice germplasm in order to identify quantitative trait loci (QTL) underpinning nutrition components and determined by measuring the normal frequency distribution for Fe, Zn, amylose, and protein content in those rice germplasm. Comparatively, the germplasm Radhuni pagal, Kalobakri, Thakurbhog (26.6 ppm) and Hatisail exhibited the highest mean values for Fe (16.9 ppm), Zn (34.1 ppm), amylose (26.6 ppm) and protein content (11.0 ppm), respectively. Moreover, a significant linear relationship (R2 = 0.693) was observed between Fe and Zn contents. Cluster analysis based on Mahalanobis D2 distances revealed four major clusters of 113 rice germplasm, with cluster III containing a maximum 37 germplasm and a maximum inter-cluster distance between clusters III and IV. The 45 polymorphic SSRs and four trait associations exhibited eight significant quantitative trait loci (QTL) located on eight different chromosomes using composite interval mapping (CIM). The highly significant QTL (variance 7.89%, LOD 2.02) for protein content (QTL.pro.1) was observed on chromosome 1 at 94.9cM position. Also, four QTLs for amylose content were observed with the highly significant QTL.amy.8 located on chromosome 8 exhibiting 7.2% variance with LOD 1.83. Only one QTL (QTL.Fe.9) for Fe content was located on chromosome 9 (LOD 1.24), and two (QTL.Zn.4 and QTL.Zn.5) for Zn on chromosome 4 (LOD 1.71) and 5 (LOD 1.18), respectively. Overall, germplasm from clusters III and IV might offer higher heterotic response with the identified QTLs playing a significant role in any rice biofortification breeding program and released with development of new varieties.


Assuntos
Oryza/genética , Locos de Características Quantitativas , Amilose/análise , Biofortificação/métodos , Produtos Agrícolas/química , Produtos Agrícolas/classificação , Produtos Agrícolas/genética , Alimentos Fortificados/análise , Genes de Plantas , Marcadores Genéticos , Ferro/análise , Valor Nutritivo , Oryza/química , Oryza/classificação , Fenótipo , Melhoramento Vegetal/métodos , Proteínas de Vegetais Comestíveis/análise , Análise de Regressão , Sementes/química , Sementes/genética , Zinco/análise
17.
Food Chem ; 324: 126863, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353657

RESUMO

In this study, 95 accessions of proso millet (Panicum miliaceum L.) were characterized for starch physicochemical properties, including apparent amylose content (AAC), gel textural properties, Rapid Visco Analyzer (RVA) pasting viscosity properties, thermal and retrogradation properties. Based on genotypic data, the genetic diversity and inter-relationship of these starch traits were analyzed. Diverse starch quality was found, for example, AAC ranged from 0 to 32.3%, gelatinization temperature (GT) varied from 71.5 to 79.0 ℃, and RVA profile showed distinct patterns among proso millet of different AAC types. Interestingly, high AAC proso millet usually had GT lower than that of low AAC proso millet, which is different from the findings in rice starch. Many starch traits were significantly correlated and most of the 18 tested traits could be classified as either AAC-related traits or GT-related traits. In summary, the information presented here will be useful for further development of proso millet products.


Assuntos
Panicum/química , Amido/química , Amilose/análise , Análise por Conglomerados , Géis/química , Genótipo , Oryza/química , Oryza/metabolismo , Panicum/genética , Panicum/metabolismo , Análise de Componente Principal , Amido/análise , Temperatura , Viscosidade
18.
J Food Sci ; 85(4): 980-988, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32180222

RESUMO

Thermal processing of pulse crops influences the type and levels of prebiotic carbohydrates present. Pulses such as common bean and chickpea are rich sources of prebiotic carbohydrates, including sugar alcohols (SAs), raffinose family oligosaccharides (RFOs), fructooligosaccharides (FOSs), resistant starch (RS), and amylose. This study determined the changes in prebiotic carbohydrate concentrations of seven common bean and two chickpea market classes after thermal processing (cooking, cooling, and reheating). A 100-g serving of common bean provides 0.7 to 10.6 mg of SAs, 3.9 to 5.2 g of RFOs, 57 to 143 mg of FOSs, 2.6 to 3.9 g of RS, and 25 to 33 g of amylose; cooling and reheating reduced RFOs but increased SAs, FOSs, and RS in many cases. A 100-g serving of chickpea (cooked at 90 °C for 4 hr) provides 1.2 to 1.7 g of SAs, 2.5 to 3.2 g of RFOs, 26 to 43 mg of FOSs, 3.6 to 5.3 g of RS, and 24 to 30 g of amylose; cooling and reheating reduced SAs and RFOs but increased FOSs, RS, and amylose concentrations. Processing methods change the nutritional quality of pulse crops by changing the type and quantity of prebiotic carbohydrates.


Assuntos
Carboidratos/análise , Cicer/química , Phaseolus/química , Prebióticos/análise , Rafinose/análise , Amilose/análise , Culinária/métodos , Produtos Agrícolas , Temperatura Alta , Valor Nutritivo , Transição de Fase , Sementes/química , Amido/análise
19.
Carbohydr Polym ; 234: 115893, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32070513

RESUMO

In rice production, pre-harvest sprouting (PHS) of late ripening seeds is one of the most serious quality defects in rice grain quality. In the present study, PHS impact was investigated by examining the physicochemical properties, eating and cooking quality (ECQ) of rice grain. Four rice cultivars suffering from PHS had impaired ECQ, reduced apparent amylose content, and decreased total starch content, with an increase in total protein content. The viscosity of flours and starches prepared from the PHS grains was significantly reduced. Starch molecular structure analysis also showed remarkable decreases in the short chains of amylopectin, long amylose chains and reduced starch crystallinity of the PHS grains. Moreover, the PHS native starch tended to have low starch digestibility. This provides useful information for understanding the effects of PHS on white rice grain quality as well as on starch fine structure and its physicochemical properties.


Assuntos
Grão Comestível/química , Oryza/química , Sementes/química , Amido/química , Amilose/análise , Configuração de Carboidratos , Físico-Química , Géis/análise , Tamanho da Partícula , Propriedades de Superfície
20.
Food Chem ; 315: 126241, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32014667

RESUMO

Chemical modification with octenyl succinic anhydride (OSA) helps to control the physicochemical and thermal properties of isolated starches. The main objective, herein, was to partially characterize modified starches from Dominico-Harton plantain and FHIA 21 planted in Colombia. The highest degree of substitution was found in FHIA 21 (0.020) starch with 3% OSA and 4-h reaction at room temperature. The grain morphology was not affected, but small changes on the surface were evident. Both modified starches reported absorption bands in the IR at 1566 and 1738 cm-1, proper for these types of starch derivatives. The hexagonal and monoclinic structures of starch were altered through chemical modification. In the bending curves, a drastic decrease in the viscosity of the modified starches was observed with respect to the native one. The gelatinization temperatures of the modified starches were similar to those of the isolated starches.


Assuntos
Plantago/química , Amido/química , Amilose/análise , Colômbia , Microscopia Eletrônica de Varredura , Plantago/crescimento & desenvolvimento , Amido/análogos & derivados , Anidridos Succínicos/química , Viscosidade , Difração de Raios X
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