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1.
Food Chem ; 304: 125434, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31491711

RESUMO

The effect of amylose content in the in vitro digestibility of non-modified and OSA-modified corn starch was studied. Corn starches with different amylose content (waxy, normal and Hylon VII) were treated with 3% OSA solution. In vitro digestibility tests showed that OSA treatment reduced the fraction of fastly digestible starch, an effect that was more pronounced for cooked starch. The amylose content was negatively linked to the decrease of in vitro digestion. HPSEC analysis was conducted to gain insights on the effect of OSA-treatment on in vitro digestibility. The results showed an increase of the molecular weight of starch chains. Besides, the molecular weight increase was similar for amylose and amylopectin fractions. This suggests that OSA could be acting as a cross-linking agent between starch chains, reducing the susceptibility to amylolysis. Overall, OSA treatment induced the formation of more complex starch chains, offering more resistance for amylolytic reactions.

2.
Food Chem ; 298: 125085, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260951

RESUMO

Plantain is a climacteric fruit having economic relevance in several tropical regions. Unripe plantain is an alternative source of indigestible carbohydrates (dietary fibre) and undigestible starch fraction. Unripe plantain flour was explored in this work as an alternative ingredient (whole and pulp) in spaghetti formulations. Chemical composition, cooking quality, texture analysis, and microstructure of spaghetti formulations were analyzed. The microstructure results showed that the presence of fiber in the food matrix helped the reduction of the starch granule swelling in the cooking process. Spaghetti made with whole plantain flour exhibited lower rapidly starch fraction, with increased resistant starch fractions. Overall, the whole unripe plantain flour exhibited good potential for gluten-free spaghetti having highest content of fiber and lower starch digestion rates.


Assuntos
Farinha , Plantago/química , Culinária , Dieta Livre de Glúten , Fibras na Dieta/análise , Digestão , Farinha/análise , Análise de Alimentos , Amido/química
3.
J Sci Food Agric ; 99(13): 5784-5791, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31162677

RESUMO

BACKGROUND: The use of byproducts such as rejected plantain with final disposition problems and conversion processes with 'green' technologies are important research topics. Bioethanol production from crops with a high content of fermentable sugars is an alternative to that from traditional crops (corn and sugar cane). The aim of this work was to study the use of whole (peel and pulp) unripe plantain (WP) for bioethanol production. RESULTS: Lab-scale liquefaction and saccharification of both materials released mainly three carbohydrates, glucose (9.02 mg g-1 ), maltose (0.45 mg g-1 ) and xylose (0.25 mg g-1 ). The WP saccharification required the use of pectinase and cellulase because of the high amounts of pectin and cellulose associated with the peel. Fermentation for 11 h produced similar ethanol concentration for both samples, but at the end of fermentation (32 h), the ethanol production was higher in the WP (58.6 mL L-1 ) compared with the plantain pulp (PP) (45.5 mL L-1 ). The theoretical ethanol yield was lower with WP (67%) than with PP (90%). CONCLUSION: WP can be an alternative raw material for bioethanol production. © 2019 Society of Chemical Industry.


Assuntos
Biocombustíveis/análise , Etanol/metabolismo , Microbiologia Industrial/métodos , Musa/química , Saccharomyces cerevisiae/metabolismo , Resíduos/análise , Biocatálise , Celulase/química , Etanol/análise , Fermentação , Frutas/química , Frutas/microbiologia , Musa/microbiologia , Poligalacturonase/química
4.
Food Chem ; 292: 1-5, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054650

RESUMO

The role of raw plantain flour (RPF) and its citric acid (CA)-esterified counterpart (EPF) on the carbohydrate nutritional properties of cookies was investigated. Cookies were elaborated with commercial wheat flour (CWF), RPF, EPF, or a CWF-EPF blend, and assessed for composition, starch digestibility, texture and sensory properties. EPF-cookie showed the lowest digestible starch (DS) content and estimated glycemic index (pGI) (25.0% and 59.3, respectively). Cookies made with CWF-EPF exhibited the highest indigestible fraction values attributed to the synergistic presence of the RS from EPF and the protein and non-starch polysaccharides from CWF. All RPF containing cookies exhibited lower hardness than CWF-cookie. Although the use of RPF decreased consumer's acceptability compared to CWF-cookie, the cookies with EPF showed sensory characteristics of 52-65% compared with the CWF-cookie (100%). This study shows CA esterification of plantain flour as a successful strategy to manufacture cookies with low DS and pGI.


Assuntos
Carboidratos da Dieta/farmacocinética , Farinha , Plantago/química , Adulto , Ácido Cítrico/química , Esterificação , Feminino , Índice Glicêmico , Dureza , Humanos , Masculino , Pessoa de Meia-Idade , Amido , Paladar , Triticum
5.
Int J Biol Macromol ; 132: 119-125, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30926504

RESUMO

The development of starch granules of a banana cultivar (morado variety - Musa AAA subgroup Red dacca) from filamentous shape to semi-spherical and finally to oval shape, was studied. The purity of the extracted starch changed from 83.5% (6 weeks) to 95.4% (16 weeks). Impurities were ascribed to cellulosic and latex fractions responsible for the integrity of the pristine fruit. The amylose content was stabilized at about 29.6% after the 12th week. The thermal analysis showed that the gelatinization enthalpy increased from 5.0 to 11.2 J/g from the 6th to the 12th week, indicating an increased degree of internal molecular organization. The analysis of chain-length distribution and gel permeation chromatography, showing that the content of long chains (B1, B2, and B3+) increased with the development of the starch granule. Also, XRD analysis indicated that C- type X-ray diffraction pattern from early to later phases of development, although the relative crystallinity content increased from 19.3 to 23.5% after 16 weeks of development. FTIR revealed the formation of more ordered structures with the development time. In vitro digestion tests showed that the resistant starch fraction increased from 37.5% for week 6 to 55.5% for week 16.


Assuntos
Digestão , Evolução Molecular , Frutas/crescimento & desenvolvimento , Musa/química , Musa/crescimento & desenvolvimento , Amido/química , Amilopectina/análise , Amilose/análise , Solubilidade , Amido/metabolismo , Temperatura Ambiente
6.
J Sci Food Agric ; 99(6): 3134-3141, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30536769

RESUMO

BACKGROUND: Starch is an alternative material for the production of biodegradable plastics; however, native starches have drawbacks due to their hydrophilic nature. Chemical modifications such as acetylation and crosslinking are used to broaden the potential end-uses of starch. Dual modification of starches increases their functionality compared to that of starches with similar single modifications. In this study, a dual-modified potato starch (acetylated and crosslinked) was used to produce films by casting. RESULTS: Changes in the arrangement of the amylopectin double helices of dual-modified starch were evident from X-ray diffraction patterns, pasting profiles and thermal properties. The degree of substitution for acetyl groups was low (0.058 ± 0.006) because crosslinking dominated acetylation. Modified starch film had higher elongation percentage (82.81%) than its native counterpart (57.4%), but lower tensile strength (3.51 MPa for native and 2.17 MPa for dual-modified) and lower crystallinity in fresh and stored films. The sorption isotherms indicated that the dual modification decreased the number of reactive sites for binding water, resulting in a reduction in the monolayer value and a decrease in the solubility and water vapor permeability. CONCLUSIONS: Dual modification of starch may be a feasible option for improving the properties of biodegradable starch films. © 2018 Society of Chemical Industry.


Assuntos
Plásticos Biodegradáveis/química , Extratos Vegetais/química , Solanum tuberosum/química , Amido/química , Acetilação , Reagentes para Ligações Cruzadas/química , Permeabilidade , Solubilidade , Resistência à Tração , Difração de Raios X
7.
J Food Sci Technol ; 55(7): 2739-2748, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30042590

RESUMO

Due to its bioactive compounds, blue maize flour is a valuable ingredient for developing gluten-free products. The incorporation of alternative flours into gluten-free pasta is a challenge as it usually results in products that, despite their enhanced nutraceutical features, show reduced quality characteristics. Composite pasta was prepared with variable (25, 50 and 75%) contents of flours from white and blue maize, chickpea and unripe plantain, following a laboratory-scale process. The composite pasta exhibited acceptable cooking loss (9-11%); pasta with blue maize showed lower hardness and chewiness, but higher adhesiveness than its white maize-based counterpart. Blue maize-based pasta presented dark color. The addition of blue maize flour at 75% conveyed the highest total phenolic content retention after extrusion (80%) and cooking (70%). Pasting profile of blue maize pasta (50 and 75%) showed a defined second viscosity peak due to re-arrangement of starch components upon cooling. The observed retention of phenolic compounds with antioxidant capacity after cooking will be useful for further development (selection of ingredients, formulations and conditions of operation) of gluten-free products with potential health benefits.

8.
Carbohydr Polym ; 197: 431-441, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30007632

RESUMO

Taro starch has the ability of producing spherical aggregates under spray-drying without the addition of binding agents. This property makes taro starch suitable for microencapsulation of dietary compounds. This study addressed the physical stability of hydrophilic and hydrophobic core materials microencapsulated by spray-drying into taro starch spherical aggregates determined from a thermodynamic standpoint via vapor adsorption isotherms. Ascorbic acid and almond oil were used as compound models. Encapsulation efficiency, GAB sorption parameters, differential and integral thermodynamic properties, Gibb's free energy, entropy-enthalpy compensation, spreading pressure, effective diffusion rate, activation energy and critical water activity were determined. The encapsulation efficiency of ascorbic acid and almond oil was 99% and 56%, respectively. Monolayer moisture content was relatively low for ascorbic acid microcapsules. The adsorption process was driven by entropic mechanisms. The physical stability of taro starch spherical aggregates microcapsules with different core material was guaranteed for a range of water activities and temperatures.

9.
Food Chem ; 263: 201-207, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29784308

RESUMO

The microstructure of cooked gluten-free pasta depends on the ingredients used, and this microstructure affects the starch hydrolysis (SH), the release of phenolic compounds (PC) and their antioxidant capacity (AC). The aim of this study was to evaluate the SD and bioaccessibility of PC during in vitro gastrointestinal digestion of gluten-free pasta and its relationship with the microstructure. The highest SH was during the intestinal phase (≈60%), but pasta with the highest content of unripe plantain and chickpea presented the lowest release of PC (≈60%). The insoluble dietary fibre could be responsible (≈12.5%) for these effects. The cooked pasta showed high AC in the intestinal phase. Regions with gelatinized starch granules in a less dense protein network and other regions with intact or swollen granules surrounded by a protein network were observed. The starch digestion and bioaccessibility of PC were related to the structure of the matrix.

10.
Food Chem ; 259: 175-180, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29680040

RESUMO

Spherical aggregates can be obtained from taro starch by spray-drying without using bonding agents. Accurate information about thermal issues of spherical aggregates can provide valuable information for assessing the application as encapsulant. Spherical aggregates of taro starch were obtained by spray-drying and analyzed using dynamic vapour sorption. The use of the Guggenheim, Anderson and de Boer (GAB) model indicated a Type II isotherm pattern with weaker interactions in the multilayer region. Differential enthalpy and entropy estimates reflected a mesoporous microstructure, implying that energetic mechanisms dominate over transport mechanisms in the sorption process. The limitation by energetic mechanisms was corroborated with enthalpy-entropy compensation estimates. The diffusivity coefficient was of the order of 10-8 m2·s-1, which is in line with results obtained for common materials used for encapsulation purposes. The thermodynamic properties and the lack of a bonding agent indicated the viability of spherical aggregates of taro starch for encapsulation of biocompounds.


Assuntos
Colocasia/metabolismo , Amido/química , Adsorção , Difusão , Porosidade , Amido/metabolismo , Temperatura Ambiente , Termodinâmica
11.
Carbohydr Polym ; 188: 121-127, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29525147

RESUMO

Nanoparticles (montmorillonite, MMT) can enhance biopolymer-based film properties. The structure-property relationship between polymers and nanoparticles may be explained by the rheological tests of nanocomposite forming solutions (NFS). The aim of this work was to study the effect of MMT concentration and amylose content on the rheological properties of NFS based on corn starch and glycerol following two preparation methods, through steady shear and dynamic tests. The organization level of NFS was influenced by the addition order of the components. Decreasing in flow index behavior when increasing amylose content was attributed to interactions between the starch components. In all NFS, G' was higher than G″ indicating a gel-like behavior and suggesting that the MMT reinforced the starch matrix as observed by the increase in the storage modulus of films with MMT. Films obtained from method 2 have better mechanical properties probably due to the starch-MMT interactions.


Assuntos
Amilose/química , Bentonita/química , Nanocompostos/química , Amido/química , Reologia , Resistência à Tração
12.
J Sci Food Agric ; 2018 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-29427318

RESUMO

In the last century, starch present in foods was considered to be completely digested. However, during the 1980s, studies on starch digestion started to show that besides digestible starch, which could be rapidly or slowly hydrolysed, there was a variable fraction that resisted hydrolysis by digestive enzymes. That fraction was named resistant starch (RS) and it encompasses those forms of starch that are not accessible to human digestive enzymes but can be fermented by the colonic microbiota, producing short-chain fatty acids. RS has been classified into five types, depending on the mechanism governing its resistance to enzymatic hydrolysis. Early research on RS was focused on the methods to determine its content in foods and its physiological effects, including fermentability in the large intestine. Later on, due to the interest of the food industry, methods to increase the RS content of isolated starches were developed. Nowadays, the influence of RS on the gut microbiota is a relevant research topic owing to its potential health-related benefits. This review summarizes over 30 years of investigation on starch digestibility, its relationship with human health, the methods to produce RS and its impact on the microbiome. © 2018 Society of Chemical Industry.

13.
Plant Foods Hum Nutr ; 72(4): 411-417, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29063352

RESUMO

The phenolic compounds, color and antioxidant capacity of gluten-free pasta prepared with non-conventional flours such as chickpea (CHF), unripe plantain (UPF), white maize (WMF) and blue maize (BMF) were analyzed. Fifteen phenolic compounds (five anthocyanins, five hydroxybenzoic acids, three hydroxycinnamic acids, one hydroxyphenylacetic acid and one flavonol) were identified in pasta prepared with blue maize, and 10 compounds were identified for samples prepared with white maize. The principal component analysis (PCA) led to results describing 98% of the total variance establishing a clear separation for each pasta. Both the proportion (25, 50 and 75%) and type of maize flour (white and blue) affected the color parameters (L*, C ab *, h ab and ΔE* ab ) and antioxidant properties (DPPH, ABTS and FRAP methods) of samples, thus producing gluten-free products with potential health benefits intended for general consumers (including the population with celiac disease).


Assuntos
Antioxidantes/análise , Farinha/análise , Fenóis/análise , Antioxidantes/farmacologia , Cicer/química , Cor , Dieta Livre de Glúten , Análise Multivariada , Plantago/química , Zea mays/química
14.
J Food Sci ; 82(9): 2016-2023, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28753728

RESUMO

Twenty-five years ago, it was found that a significant fraction of the starch present in foods is not digested in the small intestine and continues to the large intestine, where it is fermented by the microbiota; this fraction was named resistant starch (RS). It was also reported that there is a fraction of starch that is slowly digested, sustaining a release of glucose in the small intestine. Later, health benefits were found to be associated with the consumption of this fraction, called slowly digestible starch (SDS). The authors declare both fractions to be "nutraceutical starch." An overview of the structure of both fractions (RS and SDS), as well as their nutraceutical characteristics, is presented with the objective of suggesting methods and processes that will increase both fractions in starchy foods and prevent diseases that are associated with the consumption of glycemic carbohydrates.


Assuntos
Digestão , Amido/química , Amido/metabolismo , Animais , Humanos , Intestino Grosso/metabolismo
15.
Food Chem ; 211: 281-4, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27283633

RESUMO

The purpose of this study was to evaluate the effect of blue maize extracts obtained by acid-methanol treatment on the nutritional in vitro starch fractions such as: rapidly digestive starch (RDS), slowly digestive starch (SDS) and resistant starch (RS) of native and gelatinized commercial maize starch. Chromatographic analysis (HPLC-DAD/ESI-MS) of blue maize extracts showed the presence of seven anthocyanins, where cyanidin-3-(6″-malonylglucoside) was the main. Blue maize extracts modified nutritional in vitro starch fractions (decrease of RDS) while RS content increased (1.17 and 2.02 times for native and gelatinized commercial maize starch, respectively) when anthocyanins extracts were added to starch up to 75% (starch weight). This preliminary observation provides the basis for further suitability evaluation of blue maize extract as natural starch-modifier by the possible anthocyanins-starch interaction. Anthocyanin extracts can be a suitable to produce functional foods with higher RS content with potential human health benefits.


Assuntos
Antocianinas/análise , Grão Comestível/química , Pigmentos Biológicos/análise , Amido/análise , Antocianinas/metabolismo , Cromatografia Líquida/métodos , Digestão , Grão Comestível/metabolismo , Espectrometria de Massas/métodos , México , Pigmentos Biológicos/metabolismo , Extratos Vegetais/química , Amido/metabolismo
16.
Food Chem ; 200: 199-205, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26830579

RESUMO

The aim of this research was to evaluate the effect of microwave or steam pre-treatment of raw sweet potato on physicochemical and microstructural properties, and the bioaccessibility of ß-carotene in sweet potato flour. This is the first report on using the in vitro digestion model suitable for food, as proposed in a consensus paper, to assess the bioaccessibility of ß-carotene in sweet potato flour. The pre-treatments produced a rearrangement of the flour matrix (starch, protein and non-starch polysaccharides), which was greater by using microwaves (M6) conducting to a greater increase in the phase transition temperatures up to 4.14 °C, while the enthalpy presented the higher reduction (4.49 J/g), both parameters in respect to the control. The resistant starch fraction was not modified, with about 3% in all samples. Microwave (M6) and all the steam pre-treatments showed the higher bioaccessibility of ß-carotene. This flour can be used in the development of new products with high ß-carotene content.


Assuntos
Ipomoea batatas/química , Amido/química , beta Caroteno/química , Fenômenos Químicos
17.
Carbohydr Polym ; 132: 17-24, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26256319

RESUMO

Banana starch was esterified with octenylsuccinic anhydride (OSA) at different degree substitution (DS) and used to stabilize emulsions. Morphology, emulsion stability, emulsification index, rheological properties and particle size distribution of the emulsions were tested. Emulsions dyed with Solvent Red 26 showed affinity for the oil phase. Backscattering light showed three regions in the emulsion where the emulsified region was present. Starch concentration had higher effect in the emulsification index (EI) than the DS used in the study because similar values were found with OSA-banana and native starches. However, OSA-banana presented greater stability of the emulsified region. Rheological tests in emulsions with OSA-banana showed G'>G" values and low dependence of G' with the frequency, indicating a dominant elastic response to shear. When emulsions were prepared under high-pressure conditions, the emulsions with OSA-banana starch with different DS showed a bimodal distribution of particle size. The emulsion with OSA-banana starch and the low DS showed similar mean droplet diameter than its native counterpart. In contrast, the highest DS led to the highest mean droplet diameter. It is concluded that OSA-banana starch with DS can be used to stabilize specific emulsion types.


Assuntos
Emulsões/química , Musa/química , Amido/química , Anidridos Succínicos/química , Esterificação , Tamanho da Partícula , Reologia
18.
Carbohydr Polym ; 124: 17-24, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-25839789

RESUMO

Banana starches from diverse varieties (Macho, Morado, Valery and Enano Gigante) were studied in their physicochemical, structural and digestibility features. X-ray diffraction indicated that the banana starches present a B-type crystallinity pattern, with slight difference in the crystallinity level. Macho and Enano Gigante starches showed the highest pasting temperatures (79 and 78°C, respectively), whilst Valery and Morado varieties presented a slight breakdown and higher setback than the formers. Morado starch presented the highest solubility value and Valery starch the lowest one. The swelling pattern of the banana starches was in agreement with their pasting profile. All banana starches showed a shear-thinning profile. The resistant starch (RS) fraction was the main fraction in the uncooked banana starches. Morado variety showed the highest amount of slowly digestible starch (SDS) and the lowest RS content reported until now in banana starches. Banana starch cooked samples presented an important amount of SDS and RS. Molecular weight and gyration radius of the four banana starches ranged between 2.88-3.14×10(8)g/mol and 286-302nm, respectively. The chain-length distributions of banana amylopectin showed that B1 chains (DP 13-24) is the main fraction, and an important amount of long chains (DP≥37) are present. The information generated from this study can be useful to determine banana varieties for starch isolation with specific functionality.


Assuntos
Musa/química , Amido/química , Peso Molecular , Solubilidade , Difração de Raios X
19.
J Food Sci ; 80(5): C961-6, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25866197

RESUMO

An increase in celiac consumers has caused an increasing interest to develop good quality gluten-free food products with high nutritional value. Snack foods are consumed worldwide and have become a normal part of the eating habits of the celiac population making them a target to improve their nutritive value. Extrusion and deep-frying of unripe plantain, chickpea, and maize flours blends produced gluten-free snacks with high dietary fiber contents (13.7-18.2 g/100 g) and low predicted glycemic index (28 to 35). The gluten-free snacks presented lower fat content (12.7 to 13.6 g/100 g) than those reported in similar commercial snacks. The snack with the highest unripe plantain flour showed higher slowly digestible starch (11.6 and 13.4 g/100 g) than its counterpart with the highest chickpea flour level (6 g/100 g). The overall acceptability of the gluten-free snacks was similar to that chili-flavored commercial snack. It was possible to develop gluten-free snacks with high dietary fiber content and low predicted glycemic index with the blend of the 3 flours, and these gluten-free snacks may also be useful as an alternative to reduce excess weight and obesity problems in the general population and celiac community.


Assuntos
Cicer , Dieta Livre de Glúten , Análise de Alimentos , Índice Glicêmico , Musa , Amido/análise , Zea mays , Doença Celíaca/dietoterapia , Fibras na Dieta/análise , Farinha/análise , Frutas , Glutens/administração & dosagem , Humanos , Valor Nutritivo , Sementes , Lanches
20.
Int J Biol Macromol ; 70: 334-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25036604

RESUMO

Plantain starch was esterified with octenylsuccinic anhydride (OSA) at two concentrations (3 and 15% w/w) of OSA. The morphology, granule size distribution, pasting, gelatinization, swelling, and solubility of granules and structural features of the starch polymers were evaluated. Granules of the OSA-modified starches increased in size during cooking more than did the granules of the native starch, and the effect was greater at the higher OSA concentration. Pasting viscosities also increased, but gelatinization and pasting temperatures and enthalpy of gelatinization decreased in the OSA-modified starches. It was concluded that insertion of OS groups effected disorder in the granular structure. Solubility, weight average molar mass, Mw¯, and z-average radius of gyration, RGz, of the amylopectin decreased as the OSA concentration increased, indicating a decrease in molecular size.


Assuntos
Plantago/química , Amido/química , Succinatos/química , Peso Molecular , Tamanho da Partícula , Solubilidade , Termodinâmica
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