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1.
Food Res Int ; 189: 114495, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876585

RESUMO

The texture of tomato products can be modified by choice of variety, their growing conditions and/or processing method, but no clear explanation exists of the mechanisms that transform fruit tissue, how they act on texture, or whether genetics and processing impact the same physical parameters. We therefore conducted a study that processed 4 varieties produced under low/high nitrogen supply, into puree using both hot and cold break processes. No specific rheological signature allows discrimination between cultivar-induced or process-induced textural changes, but that they can be distinguished by sensory analysis. Growth conditions impacted but was not sensory distinguished. Both caused significant variations in 7 of 11 physico-chemical parameters, but the order of importance of these traits controlling texture varied, depending on whether the cause was genetic or process-related. Analysis of alcohol insoluble solids revealed a specific signature in pectin composition and conformation that could be linked to particle aggregation in the presence of lycopene-rich particles.


Assuntos
Manipulação de Alimentos , Frutas , Reologia , Solanum lycopersicum , Solanum lycopersicum/química , Viscosidade , Manipulação de Alimentos/métodos , Frutas/química , Pectinas/química , Licopeno/análise , Paladar , Carotenoides/análise , Carotenoides/química , Humanos
2.
Int J Psychiatry Clin Pract ; : 1-10, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38019133

RESUMO

OBJECTIVE: Hoarding behaviour is a common but poorly characterised problem in real-world clinical practice. Although hoarding behaviour is the key component of Hoarding Disorder (HD), there are people who exhibit hoarding behaviour but do not suffer from HD. The aim of the present study was to characterise a clinical sample of patients with clinically relevant hoarding behaviour and evaluate the differential characteristics between patients with and without HD. METHODS: This study included patients who received treatment at the home visitation program in Barcelona (Spain) from January 2013 through December 2020, and scored ≥ 4 on the Clutter Image Rating scale. Sociodemographic, DSM-5 diagnosis, clinical data and differences between patients with and without an HD diagnosis were assessed. RESULTS: A total of 243 subjects were included. Hoarding behaviour had been unnoticed in its early stages and the median length in the sample was 10 years (IQR 15). 100% of the cases had hoarding-related complications. HD was the most common diagnosis in 117 patients (48.1%). CONCLUSIONS: The study found several differential characteristics between patients with and without HD diagnosis. Alcohol use disorder could play an important role among those without HD diagnosis. Home visitation programs could improve earlier detection, preventing hoarding-related complications.

3.
Food Res Int ; 173(Pt 2): 113409, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803750

RESUMO

Phenolic compounds are known inhibitors of starch digestion through binding with α-amylase. However, a growing body of research shows that phenolic-starch interactions at the molecular level may interfere with this inhibition potential. In this study, we evaluated the effect of Gallic Acid (GA) as a model phenolic compound on starch digestion kinetics carried out in vitro in a Rapid ViscoAnalyzer (RVA). The results showed that when GA was added before cooking of starch in order to promote starch-GA complexation, the rate of digestion of starch was similar to that of starch alone, and faster than when GA was added after cooking of starch. The results demonstrated that when GA was introduced after cooking of starch, GA inhibited α-amylase strongly and that inhibition increased with starch paste viscosity only for potato and wheat starches. No correlation was found between starch molecular characteristics and the inhibiting capacity of GA at different starch concentrations. However, the apparent influence of starch chain length distribution suggested that physical effects (such as the absorption of GA at the surface of the starch paste) may play a role in the capacity of GA to inhibit α-amylase.


Assuntos
Ácido Gálico , Amido , Amido/química , Ácido Gálico/farmacologia , Digestão , alfa-Amilases/metabolismo , Fenômenos Químicos
4.
J Sci Food Agric ; 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37559127

RESUMO

BACKGROUND: Consumer preferences for boiled or fried pieces of roots, tubers and bananas (RTBs) are mainly related to their texture. Different raw and cooked RTBs were physiochemically characterized to determine the effect of biochemical components on their cooking properties. RESULTS: Firmness in boiled sweetpotato increases with sugar and amylose contents but no significant correlation was observed between other physicochemical characteristics and cooking behaviour. Hardness of boiled yam can be predicted by dry matter (DM) and galacturonic acid (GalA) levels. For cassava, no significant correlation was found between textural properties of boiled roots and DM, but amylose and Ca2+ content were correlated with firmness, negatively and positively, respectively. Water absorption of cassava root pieces boiled in calcium chloride solutions was much lower, providing indirect evidence that pectins are involved in determining cooking quality. A highly positive correlation between textural attributes and DM was observed for fried plantain, but no significant correlation was found with GalA, although frying slightly reduced GalA. CONCLUSION: The effect of main components on texture after cooking differs for the various RTBs. The effect of global DM and major components (i.e. starch, amylose) is prominent for yam, plantain and sweetpotato. Pectins also play an important role on the texture of boiled yam and play a prominent role for cassava through interaction with Ca2+ . © 2023 Bill and Melinda Gates Foundation. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

5.
J Sci Food Agric ; 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37471517

RESUMO

BACKGROUND: Yam is a major staple food that provides both energy (starch) and bioactive compounds. However, there is a lack of knowledge on its cooking quality. We have determined the cooking quality of five varieties of water yam (among those most appreciated by consumers), when they were steamed or boiled. The yams were grown in two contrasting locations with regard to pedoclimatic conditions. RESULTS: Ratio of length to mean circumference of the tuber, difficulty to peel, cooking time, color attributes, hardness of steamed pulp, and dry matter (DM) and starch contents significantly varied among varieties. Cooking time and hardness of the cooked pulp, either steamed or boiled, were higher for tubers grown at the drier location, with vertisols, than at the rainy one, with a ferralitic soil. The raw pulp was richer in starch at the rainy location. We found no correlation between either textural properties or DM and the cooking time. A slight (r = 0.44) but significant correlation was recorded between the DM of the raw pulp and the hardness of the steamed product. CONCLUSION: We propose a comprehensive multicriteria approach for determination of yam cooking quality, textural properties, color attributes and chemical composition, along with varietal and environmental influences. This approach takes into consideration the complexity of food quality, allows a better understanding of its determinants and provides a basis for useful guidelines for breeders. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

6.
Actas Esp Psiquiatr ; 50(5): 226-232, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36273382

RESUMO

The role of caregivers is essential during home hospitalization since they act as co-therapists, being the level of responsibility experienced by them higher than usual.


Assuntos
Satisfação Pessoal , Psiquiatria , Humanos , Satisfação do Paciente , Cuidadores , Hospitalização
7.
Actas esp. psiquiatr ; 50(5): 226-232, septiembre 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-211144

RESUMO

Introducción: El rol de los cuidadores es esencial durantela hospitalización domiciliaria ya que ejercen de coterapeutas,siendo el nivel de responsabilidad que experimentan mayora la habitual. El objetivo de este estudio es evaluar lasobrecarga experimentada en los cuidadores principalesy también determinar el nivel de satisfacción percibida enlos cuidadores principales y en los pacientes atendidos ennuestra unidad de hospitalización domiciliaria (HADMar).Metodología. Estudio prospectivo observacional. Se hanincluido todos los pacientes que han ingresado en HADMarentre mayo de 2020 y abril de 2021. Se han recogido datossocio-demográficos y clínicos de la muestra. Para evaluar elgrado de sobrecarga se ha utilizado la escala de Zarit al finaldel ingreso en los cuidadores principales. Para determinar lasatisfacción percibida se ha administrado la escala CRES-4 alfinal del ingreso tanto a los cuidadores como a los pacientesatendidos.Resultados. 182 pacientes han sido atendidos. Del total,144 cuidadores principales han respondido la escala de Zarit,siendo la puntuación media de 49,59 (correspondiente asobrecarga ligera). 152 cuidadores han respondido la escalaCRES-4, obteniendo una puntuación media de 241,75 (sobreun máximo posible de 300). 158 pacientes han respondido laescala CRES-4 y la puntuación media ha sido 242,57. (AU)


Introduction: The role of caregivers is essential duringhome hospitalization since they act as co-therapists, beingthe level of responsibility experienced by them higher thanusual. The objective of this study is to evaluate the burdenexperienced in the main caregivers and also to determine thelevel of satisfaction perceived in the main caregivers and in thepatients attended in our home hospitalization unit (HADMar).Methodology. Prospective observational study. Allpatients admitted to HADMar between May 2020 and April2021 have been included. Socio-demographic and clinicaldata have been collected from the sample. To assess thedegree of burden, the Zarit scale was used at the end ofadmission in the main caregivers. To determine the perceivedsatisfaction, the CRES-4 scale was administered at the end ofadmission to both the caregivers and the patients attended.Results. 182 patients have been attended. Of them, 144main caregivers answered the Zarit scale, being the meanscore 49.59 (corresponding to mild burden). 152 caregivers answered the CRES-4 scale, obtaining a mean score of241.75 (out of a possible maximum of 300). 158 patientsanswered the CRES-4 scale and the mean score was 242.57. (AU)


Assuntos
Humanos , Cuidadores , Hospitalização , Satisfação do Paciente , Satisfação Pessoal , Pacientes , Psiquiatria
8.
Food Funct ; 13(18): 9254-9267, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-35980275

RESUMO

Amylose-free and wild-type cassava starches were fermented for up to 30 days and oven- or sun-dried. The specific volume (ν) after baking was measured in native and fermented starches. The average ν (across treatments) for waxy starch was 3.5 times higher than that in wild-type starches (17.6 vs. 4.8 cm3 g-1). The best wild-type starch (obtained after fermentation and sun-drying) had considerably poorer breadmaking potential than native waxy cassava (8.4 vs. 16.4 cm3 g-1, respectively). The best results were generally obtained through the synergistic combination of fermentation (for about 10-14 days) and sun-drying. Fermentation reduced viscosities and the weight average molar mass led to denser macromolecules and increased branching degree, which are linked to a high loaf volume. The absence of amylose, however, was shown to be a main determinant as well. Native waxy starch (neutral in taste, gluten-free, and considerably less expensive than the current alternatives to cassava) could become a new ingredient for the formulation of clean label-baked or fried expanded products.


Assuntos
Manihot , Amilopectina , Amilose , Dieta Livre de Glúten , Amido
9.
Carbohydr Polym ; 281: 119086, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35074113

RESUMO

During processing of plant-based foods, cell wall polysaccharides and polyphenols, such as procyanidins, interact extensively, thereby affecting their physicochemical properties along with their potential health effects. Although hemicelluloses are second only to pectins in affinity for procyanidins in cell walls, a detailed study of their interactions lacks. We investigated the interactions between representative xylose-containing water-soluble hemicelluloses and procyanidins. Turbidity, ITC and DLS were used to determine the relative affinities, and theoretical calculations further ascertained the interactions mechanisms. Xyloglucan and xylan exhibited respectively the strongest and weakest interactions with procyanidins. The different arabinoxylans interacted with procyanidins in a similar strength, intermediate between xyloglucans and xylans. Therefore, the strength of the interaction depended on the structure itself rather than on some incidental properties, e.g., viscosity and molar mass. The arabinose side-chain of arabinoxylan did not inhibit interactions. The computational investigation corroborated the experimental results in that the region of interaction between xyloglucan and procyanidins was significantly wider than that of other hemicelluloses.


Assuntos
Proantocianidinas , Parede Celular/química , Pectinas/química , Polissacarídeos/química , Proantocianidinas/química , Xilanos/química , Xilose/análise
10.
Artigo em Espanhol | MEDLINE | ID: mdl-34840634

RESUMO

INTRODUCTION: Since the COVID-19 pandemic began, warnings have been made about the impact on the mental health of the population and as occurred in previous pandemics, an increase in suicide rates had been anticipated. To date, studies differ with regard to whether suicide rates are being affected during the COVID pandemic. MATERIAL AND METHODS: All individuals registered for suicidal ideation or suicidal attempt in the Suicide Risk Code (CRS) from the city of Barcelona from January 1, 2018 to June 30, 2021 have been included. A bivariate analysis has been carried out between the 2018-2019 period and the pandemic period. The percentage increase in the monthly incidence of CRS cases has been calculated, using the average monthly incidence for the 2018-2019 period as a reference. RESULTS: A total of 3388 consultations for suicide ideation or suicidal attempt were registered. There has been an increase of 43.20% in the monthly incidence of suicidal ideation and suicidal attempts during the pandemic compared to the 2018-2019 period, reaching a maximum increase of 573.8% in young people under 18 years in the month of May 2021. CONCLUSIONS: During the COVID-19 pandemic period, consultations for suicidal ideation and suicidal attempts have increased compared to the previous 2 years in the city of Barcelona. It should be noted this growth especially in young people under 18 years.

11.
Int J Food Sci Technol ; 56(3): 1135-1147, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33776226

RESUMO

This study aimed at understanding users' demand for raw and boiled plantains in rural and urban areas in West and Littoral regions of Cameroon. Surveys conducted in eight rural localities consisted of key informant interviews, gender-disaggregated focus group discussions, market and individual interviews. Processing and cooking diagnoses were done with restaurant cooks in urban areas, to know the details of plantain processing and boiling and to understand the quality characteristics of raw plantain that give a most-liked boiled plantain. Local favourite landraces, most cultivated landraces in Cameroon (Batard and Big ebanga) and a new CARBAP/CIRAD hybrid (CARBAP K74) were used. The preference for plantain cultivars was both gender and region-dependent. High-quality plantain should be mature, with big fingers and having a dark green peel colour. The fruit length and girth, pulp pH, dry matter content and firmness were found to be relevant postharvest quality characteristics for plantain breeding improvement.

12.
Molecules ; 25(12)2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32570969

RESUMO

Starch, an abundant and low-cost plant-based glucopolymer, has great potential to replace carbon-based polymers in various materials. In order to optimize its functional properties for bioplastics applications chemical groups need to be introduced on the free hydroxyl groups in a controlled manner, so an understanding of the resulting structure-properties relationships is therefore essential. The purpose of this work was to study the multiscale structure of highly-acetylated (degree of substitution, 0.4 < DS ≤ 3) and etherified starches by using an original combination of experimental strategies and methodologies. The molecular structure and substituents repartition were investigated by developing new sample preparation strategies for specific analysis including Asymmetrical Flow Field Flow Fractionation associated with Multiangle Laser Light Scattering, Nuclear Magnetic Resonance (NMR), Raman and Time of Flight Secondary Ion Mass spectroscopies. Molar mass decrease and specific ways of chain breakage due to modification were pointed out and are correlated to the amylose content. The amorphous structuration was revealed by solid-state NMR. This original broad analytical approach allowed for the first time a large characterization of highly-acetylated starches insoluble in aqueous solvents. This strategy, then applied to characterize etherified starches, opens the way to correlate the structure to the properties of such insoluble starch-based materials.


Assuntos
Amilose/química , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Peso Molecular
13.
Carbohydr Polym ; 230: 115591, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887855

RESUMO

Maize starch was plasticized by glycerol, choline chloride ([Chol][Cl]) and ionic liquids (Choline acetate ([Chol][Ace]), 1-Ethyl-3-methylimidazolium Chloride ([EMIM][Cl]) and 1-Ethyl-3-methylimidazolium acetate ([EMIM][Ace]). Melt rheology at 120 °C was assessed with a twin-screw micro-compounder used for processing small quantities (8-10 g), and with a capillary rheometer with pre-shearing (Rheoplast). Qualitative agreement was found between shear viscosities obtained by both rheometry devices, showing the interest of the micro-compounder for screening of plasticizers' influence. The lower shear viscosity values were obtained in presence of [EMIM][Ace] whereas [Chol][Cl] led to the largest ones. Rather than processing induced macromolecular degradation, the glass transition temperature depressing effect of the plasticizers was found to better explain viscosity differences. This underlines the strong influence of the nature of the plasticizers on starch melt rheology. Finally, results from extensional viscosity shows the specific influence of [EMIM][Ace], suggesting that this plasticizer could be particularly relevant for thermoplastic starch processing.

14.
Carbohydr Polym ; 205: 143-150, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30446089

RESUMO

This work investigates the macromolecular structure of native and amylomaltase (AM) treated cassava starch at various reaction times. AM-treated starches showed lower amylose content compared to their parental starch. Long chain proportions (DP 25-80) increased with reaction time up to 4 h and then slightly decreased at 24 h. Macromolecular and fine structure of AM-treated starches for 5 min (AM5min) and 4 h (AM4 h) were characterized more deeply by using HPSEC-MALLS and H1 NMR combined with ß-amylolysis and MALDI-TOF-MS. Molar mass and dispersity of both AM-treated starches were lowered. Nevertheless, AM5min had longer external chains whereas AM4 h exhibited a larger and denser macromolecular core. A cyclo-structure with DP 8 was found in both AM-treated starches; however, AM4 h contained cyclo-structures with various sizes (DP 8-32). Finally, by controlling reaction time and substrate constituents, which are important factors affecting the AM action modes, AM-treated starch with various structural features can be obtained.


Assuntos
Amilopectina/química , Amilose/química , Sistema da Enzima Desramificadora do Glicogênio/química , Manihot/química , Hidrólise , Estrutura Molecular , Peso Molecular , Tamanho da Partícula
15.
Carbohydr Polym ; 194: 80-88, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29801861

RESUMO

Starch granules can be extruded to obtain a thermoplastic material. Thermoplastic starch (TPS) usually requires a significant break down of the starch granular organization to form a continuous polysaccharide matrix. In this work, we extrude potato starch with and without a plasticizer and store samples at high humidity to generate recrystallization. A multi-scale investigation of the microstructure is performed by combining different techniques: WAXS and solid-state NMR to describe macromolecule organization and Second Harmonic Generation (SHG) imaging to provide spatial information. Finally, the ability of the material to swell and remain sound in water is assessed. Glycerol-plasticized samples swell the least despite many granules with native-like structure embedded in the starch matrix. Glycerol limits the fragmentation and melting of the granules and crystallites during extrusion but also reduces the proportion of starch molecules in constrained conformations, enabling the formation of a polymer network that can sustain the penetration of water.


Assuntos
Imageamento por Ressonância Magnética , Microscopia de Geração do Segundo Harmônico , Amido/química , Temperatura , Configuração de Carboidratos
16.
Carbohydr Polym ; 193: 289-297, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29773384

RESUMO

Polysaccharide-surfactant blends are widely used in foods. However, their possible mutual interactions have not been extensively studied. The purpose of this work was to examine how the anionic surfactant sodium stearoyl lactylate (SSL) affects different properties of κ-carrageenan solutions and gels. Rheometry, differential scanning calorimetry, asymmetrical flow field-flow fractionation coupled with multiangle laser light scattering, among others, were used to determine the flow and viscoelastic behavior, thermal transitions, and conformation changes, respectively. Interference caused by SSL is postulated as the primary factor to explain the variations in the conformation of κ-carrageenan in gels and solutions. However, electrostatic repulsions between κ-carrageenan and SSL can also be involved. These latter interactions are more important for high SSL concentrations (13 mmol dm-3) without addition of KCl, because of the higher net negative charge density of the system. SSL significantly modifies the properties of κ-carrageenan in aqueous media.


Assuntos
Carragenina/química , Conformação Molecular , Estearatos/química , Tensoativos/química , Temperatura , Géis/química , Reologia , Soluções
17.
Carbohydr Polym ; 184: 57-65, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29352943

RESUMO

Potato and pea starches were processed on a twin-screw extruder under various moisture and thermomechanical conditions, chosen to keep material temperature Te close to starch melting temperature, Tm, whilst avoiding die expansion. Extruded rods were analysed by asymmetrical flow field flow fractionation coupled with light scattering, X-ray diffraction, DSC, and light microscopy with image analysis. Molar mass of extruded materials decreased more for potato than for pea starch, when specific mechanical energy SME increased, likely because of larger amylopectin sensitivity to shear. No crystallinity was detected when ΔT = (Tm-Te) ≤ 0. Residual gelatinization enthalpy ΔHg decreased with ΔT. As illustrated by larger ΔT values for ΔHg = 0, decreasing moisture favored melting, likely by increasing solid friction. The fraction of granular remnants of potato starch was inversely correlated to SME. These results could be explained by considering starch melting during extrusion as a suspension of solid particles embedded in a continuous amorphous matrix.

18.
Carbohydr Polym ; 181: 337-344, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253980

RESUMO

New α(1→2) or α(1→3) branched dextrans with high molar masses and controlled architecture were synthesized using a dextransucrase and branching sucrases. Their molecular structure, solubility, conformation, film-forming ability, as well as their thermal and mechanical properties were determined. These new dextrans present structures with low densities from 9,500 to 14,000gm-3 in H2O/DMSO medium, their molar mass, size and dispersity increase with increasing branching degree (weight-average molar mass up to 109gmol-1 and radius of gyration around 500nm). Dextrans exhibit a glass transition between 40.5 and 63.2°C for water content varying from 12.2 to 14.1%. The effect of branching is mainly observed on the ability of dextran to crystallize. They have a good film-forming ability with a storage modulus which varies from 2 to 4GPa within a relative humidity range of 10-50%.


Assuntos
Dextranos/química , Dextranos/metabolismo , Glucosiltransferases/metabolismo , Substâncias Macromoleculares/química , Sacarase/metabolismo , Varredura Diferencial de Calorimetria , Dextranos/ultraestrutura , Módulo de Elasticidade , Vidro , Umidade , Hidrodinâmica , Peso Molecular , Sacarose/metabolismo , Temperatura de Transição , Água/química
19.
Carbohydr Polym ; 179: 10-18, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29111031

RESUMO

A gene encoding a novel dextransucrase was identified in the genome of Oenococcus kitaharae DSM17330 and cloned into E. coli. With a kcat of 691s-1 and a half-life time of 111h at 30°C, the resulting recombinant enzyme -named DSR-OK- stands as one of the most efficient and stable dextransucrase characterized to date. From sucrose, this enzyme catalyzes the synthesis of a quasi linear dextran with a molar mass higher than 1×109g·mol-1 that presents uncommon rheological properties such as a higher viscosity than that of the most industrially used dextran from L. mesenteroides NRRL-B-512F, a yield stress that was never described before for any type of dextran, as well as a gel-like structure. All these properties open the way to a vast array of new applications in health, food/feed, bulk or fine chemicals fields.


Assuntos
Dextranos/biossíntese , Glucosiltransferases/metabolismo , Oenococcus/enzimologia , Proteínas Recombinantes/metabolismo , Sequência de Aminoácidos , Biocatálise , Configuração de Carboidratos , Bases de Dados de Proteínas , Glucosiltransferases/genética , Oenococcus/genética , Proteínas Recombinantes/genética , Sacarose/química , Sacarose/metabolismo , Viscosidade
20.
Carbohydr Polym ; 177: 424-432, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28962788

RESUMO

Native starch containing 12% water was melt processed in presence of 23% of various plasticizers at 120°C, either by simple compression molding or by extrusion using a laboratory scale microcompounder. Glycerol, a typical starch plasticizer, was used as a reference and compared to three choline salts: raw choline chloride (which is a solid in dry state with a melting point above 300°C), and two ionic liquids synthesized from this precursor (choline acetate and choline lactate, liquids below 100°C). These ionic plasticizers were shown to allow a more efficient melting of native starch in both processes. The investigation of macromolecular structure changes during processing shows that this efficiency can be ascribed to a starch chain scission mechanism, resulting in lower specific mechanical energy input need for starch thermoplasticization compared to glycerol plasticized starch. Compared to the synthesized ionic liquids, raw commercial choline chloride leads to a good compromise between limited chain scission, and final water uptake and thermomechanical properties.


Assuntos
Colina/química , Líquidos Iônicos/química , Plastificantes/química , Amido/química , Glicerol
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