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This review aimed to explore the impact of extrusion on Andean grains, such as quinoa, kañiwa, and kiwicha, highlighting their macromolecular transformations, technological innovations, and contributions to food security. These grains, which are rich in starch, high-quality proteins, and antioxidant compounds, are versatile raw materials for extrusion, a continuous and efficient process that combines high temperatures and pressures to transform structural and chemical components. Extrusion improves the digestibility of proteins and starches, encourages the formation of amylose-lipid complexes, and increases the solubility of dietary fiber. However, it can degrade heat-sensitive nutrients, such as certain amino acids. The role of extrusion in food innovation is highlighted, especially in the creation of healthy and functional products such as snacks, gluten-free pastas, and meat analogs. Some innovations in the extrusion process and future trends, such as the use of artificial intelligence to optimize formulations and customize products, have been presented. The importance of Andean grains in the fight against food insecurity has been emphasized. These grains can be transformed into accessible, long-lasting, and nutritious foods, diversifying the diet and taking advantage of local resources. This review aims to serve as a valuable guide for researchers, food developers, and policymakers in their pursuit of creating more accessible, nutritious, and sustainable food options to meet escalating global demands for food security and enhanced nutrition.

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The focus of this work was to evaluate the differences between the thermal and mechanical effects generated by ultrasound waves on the properties of corn starch, which facilitate the subsequent enzymatic hydrolysis for the generation of porous starches. The results showed that both the thermal and mechanical effects have the capacity to disorganize/alter the structure of starch, impacting on its properties. Characteristics such as particle size, pasting and thermal properties (peak viscosity 1400-1800 cp. and gelatinization enthalpy 4.5-11 J/g) of starch and water absorption were the most affected, while crystallinity was practically unmodified (crystallinity % 23-25). The thermal effect induced by the ultrasound treatment caused most of the alterations in the properties of corn starch. It was associated with the partial gelatinization of the material due to an increase in the system's temperature (up to 65° C). The effect of the mechanical phenomenon of the treatment by ultrasound waves contributed to a lesser extent compared to the thermal effect. The mechanical effect can extend over time, without the aggravating factor of causing starch gelatinization. The combination of both effects could synergistically modify the granular structure of starch. In conclusion, ultrasound waves as a pre-treatment to enzymatic hydrolysis can cause structural disorganization of starch granules and facilitate the subsequent enzymatic attack for the production of porous starches.

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Dry heat treatment (DHT) is considered a green technology to modify starch structure and functionality since it does not generate effluents and avoids the use of chemical compounds, however, there is still no comprehensive understanding of the effects and mechanisms on the multi-scale structure and their relationship with functionality. This paper reviewed and analyzed the effects of DHT on multi-scale starch structures and functional properties, compared the performance of continuous and repeated DHT, discussed a mechanism of starch dry heating, and summarized the applications of dry-heated starches. DHT evaporates water, accelerates the movement of starch molecules, and breaks hydrogen bonds, which changes the multi-scale structure. In turn, structural modifications promoted by DHT affect the hydration properties, thermal stability, slowly digestible/resistant starch formation, and glycemic index. The multi-scale structure and functional changes after DHT are strongly affected by the starch botanical source and process conditions. This review contributes to understanding the starch DHT modification and establishes a theoretical basis for advancing DHT applications in the starch industry.

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This study aimed to explore the effects of egg albumin protein addition (5, 15 and 20 g/100 g db) on the textural characteristics, as well as in the in vitro digestibility of protein and starch of wheat bread. Egg albumin addition resulted in smoother bread loaves as compared to traditional wheat bread. Reduced hardness and increased cohesiveness were correlated to the protein secondary structure, mainly with the content of ß-sheets. The in vitro protein digestibility decreased with the albumin addition, suggesting the mediation of protein-starch interactions. The in vitro starch digestibility was also decreased, reflected in a huge decrease of the slowly digestible starch fraction, but with non-significant changes in the rapidly digestible starch fraction. The supplemented albumin can form a physical barrier around the starch granules, which hampers the access of the amylolytic enzymes to the starch chains. Overall, the results of this study suggest that the addition of egg albumin is a viable alternative for producing wheat bread with reduced glycemic index and improved nutritional properties.

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The Amazon region holds untapped potential with its starch-rich tubers, which are not yet industrialized and face a risk of extinction due to competition from widely cultivated crops. Beyond their traditional subsistence use, Amazonian tubers such as Mairá and Ariá can be utilized as starch sources, offering an opportunity to support regional agriculture, preserve indigenous heritage, and provide sustainable income streams. This study aimed to characterize starches extracted from Mairá (MPS) and Ariá (ARS for rhizome and APS for potato), focusing on their technological and functional potential. Following extraction (maceration, filtration, decantation, and drying), their structure and size were analyzed using SEM and optical microscopy. Amylose content was determined spectrophotometrically, while pasting and thermal properties were assessed using RVA and DSC techniques. They exhibited axial diameters of 18.9, 22.6, and 26.7 µm, with MPS, ARS, and APS displaying spherical, elliptical, and polygonal shapes, respectively. According to RVA results, MPS showed lower viscosity and paste stability compared to others, making it more suitable for products requiring minimal thickening. Ariá starches demonstrated a rapid retrogradation and the formation of opaque pastes, indicating potential applications in products requiring these characteristics. Starches from these Amazonian tubers present significant potential as thickening and gelling agents for the food industry, standing out for their safety in consumption and their role in preserving endangered species.

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Despite the significant socioeconomic impact of yam cultivation in developing countries, this field needs more scientific studies and incentives. In Brazil, the absence of a developed processing chain has resulted in a considerable production loss due to the predominant form of commercialization (in natura). This study aimed was to examine the physicochemical and technological composition of yams of the species Dioscorea trifida L., including both white and purple varieties. The aim was to contribute to an increase in food utilization and technological potential. The proximate composition of the flours indicated that the yam species investigated have the potential for human consumption and are good sources of energy (1,489 and 1,527 kJ), with considerable levels of total fiber (8.18 and 6.69 g 100 g-1), potassium (1,325 and 981 mg 100 g-1), and phenolic compounds (133 and 110 mg 100 g-1) for white and purple yams, respectively. Additionally, the yams demonstrated distinct properties in water and oil, indicating their potential for use in breading applications. The viscoamylographic profiles of purple yam flour and yam starches were found suitable for use in quick-cooking foods that reach high viscosity when heated, whereas white yam flour was identified as a suitable thickening agent. The yams yielded flours and starches with favorable characteristics as food ingredients, offering greater added value and enhanced stability compared to the original raw materials. They present a sustainable alternative for reducing post-harvest losses and, as they are gluten-free, they cater to the celiac population.

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Plants' physiology changes through the day because photoassimilates can increase water-soluble carbohydrate concentration in the afternoon compared to the morning. This study evaluated the harvest time effect on whole-plant corn silage morphological composition, particle size, fermentation profile, chemical composition, in vitro degradation, and estimated milk yield. A two-year agronomic assay was performed in a completely random design, and one experimental silo was produced by each parcel (n = 16). The afternoon harvest increased (P < 0.01) dry matter content compared to the morning harvest. Harvest time did not affect (P ≥ 0.32) corn grain, stalk, leaf proportion, and silage particle size. However, the morning harvest increased dry matter recovery (P = 0.01) and had no effect (P ≥ 0.10) on silage pH and concentrations of lactic and acetic acid compared to the afternoon harvest. In addition, afternoon harvest instead of morning harvest increased (P ≤ 0.05) silage starch, water-soluble carbohydrates, acid detergent lignin, and ether extract content and dry matter in vitro degradation. Controversially, treatments showed no effect (P ≥ 0.14) on silage energy concentration, estimated energy content, and milk yield. Thus, the morning harvest produces more silage dry matter, but the afternoon harvest improves corn silage's nutritional value with no impact on estimated milk yield.

A fisiologia das plantas muda ao longo do dia porque os fotoassimilados podem aumentar a concentração de carboidratos solúveis em água à tarde em comparação com a manhã. Este estudo teve como objetivo avaliar o efeito do horário de colheita na composição morfológica da silagem de milho de planta inteira, tamanho de partícula, perfil de fermentação, composição química, degradação in vitro e estimativa da produção de leite. Um ensaio agronômico de dois anos foi realizado em delineamento inteiramente casualizado, e um silo experimental foi produzido por cada parcela (n = 16). A colheita da tarde aumentou (P < 0,01) o teor de matéria seca em relação à colheita da manhã. A época de colheita não afetou (P ≥ 0,32) a proporção de grãos, colmos e folhas do milho e o tamanho das partículas da silagem. Entretanto, a colheita da manhã aumentou (P = 0,01) a recuperação de matéria seca e não teve efeito (P ≥ 0,10) no pH da silagem e nas concentrações de ácido láctico e acético em comparação à colheita da tarde. Além disso, a colheita da tarde, em vez da colheita da manhã, aumentou (P ≤ 0,05) o amido da silagem, os carboidratos solúveis em água, a lignina detergente ácida e o teor de extrato etéreo e a degradação in vitro da matéria seca. Controversamente, os tratamentos não mostraram efeito (P ≥ 0,14) na concentração de energia da silagem, no conteúdo energético estimado e na produção de leite. Assim, a colheita da manhã produz mais matéria seca da silagem, mas a colheita da tarde melhora o valor nutricional da silagem de milho sem impacto na produção estimada de leite.

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Two starch to protein ratios (high starch [HS], 25% starch and 36% protein; high protein [HP], 15% starch and 53% protein on DM basis) and two moisture contents (5%, dry kibbles; 80%, wet food) were compared in a 2 x 2 factorial arrangement totaling 4 diets. Each diet was evaluated in 9 cats, with 8 d of total collection of urine and feces. Results were subjected to an analysis of variance of the effects of starch to protein ratio, moisture content and their interactions (P<0.05). Urine density was lower and volume was higher in cats fed wet foods (P<0.01). Calcium (Ca) urine concentration was higher for dry and HP diets (P<0.05). The oxalate urine concentration was 60% higher for cats fed both HS formulations (dry and wet; P<0.05). The relative supersaturation (RSS) of urine for calcium oxalate was higher for dry foods and HS formulations (P<0.01), and for struvite, it was lower for both wet foods, and among the dry diets, it was lower for the HS than for the HP formulation (P<0.01). Foods with a high protein-to-starch ratio reduced urine oxalate and RSS for calcium oxalate in wet and dry diets, and wet foods reduced RSS for calcium oxalate and struvite.

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Smart films of starch/pectin and purple carrot peel (PCP) containing anthocyanins were developed, characterized, and used as pH-responsive tags to monitor plant-based chicken analogous. This study innovates by incorporating PCP in the film solution both as an extract and as a powder, and the resulting tags were applied to a plant-based food. PCP powder <100-mesh was directly incorporated into the film-forming suspension. For powder >100-mesh, two extracts were tested: an aqueous solution and a 1 % NADES solution added to the film-forming suspension. Quantification of PCP anthocyanins by HPLC showed a higher extraction under acidic conditions (1664 mg C3G equivalents 100 g-1). Films with PCP presented greater light protection. Films with 15 % and 25 % PCP and those with added extract showed better tensile strength (3.0-3.6 MPa), elongation at break (16-20 %) and a water contact angle of 52°. All films responded to pH variations (1 to 14) and ammonia vapor and showed ΔE* values >5. After 3 days, films used as smart tags monitoring chicken analogous presented noticeable color differences for PCPNADES (55 ± 8) and 15%PCP (40 ± 1). PCP showed strong potential as a pigmenting agent in films, especially as an aqueous extract with NADES for use as pH-responsive tags in chicken analogous.

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This study evaluated the effects of different sources (sulfate vs. hydroxychloride) of Cu, Mn, and Zn during feed restriction and a high-starch diet on heifer growth performance. On day 0, Nelore heifers (n = 40) were stratified by body weight (BW = 238 ±â€…38 kg) and age (21 ±â€…1 mo), and individually allocated into 1 of the 40 drylot pens. The study was divided into periods of pen acclimation (days 0 to 27), nutrient surplus (days 28 to 55), nutrient restriction (days 56 to 83), and step-up adaptation to a high-starch diet (days 84 to 112). Heifers had free choice access to Tifton hay (Cynodon sp.) and salt from days 0 to 27. On day 28, 20 heifers/treatment were randomly assigned to receive free choice access to Tifton hay and protein supplementation at 0.10% of BW (dry matter, DM) added with sulfate (SUL) or hydroxychloride (HYD) sources of Cu, Mn, and Zn from days 28 to 112. From days 56 to 83, heifers were offered 50% of the average hay DM intake obtained from days 50 to 55. From days 84 to 112, each respective protein supplement was mixed with a starch-based total mixed ration and the concentrate DM amount was gradually increased every 7 d (starting with 35% concentrate and 65% hay on day 84 and ending with 80% concentrate and 20% hay from days 106 to 112). Effects of treatment × day and treatment were not detected (P ≥ 0.37) for heifer BW, fecal pH, average daily gain (ADG), and DM intake, except for ADG from days 28 to 56, which was less (P = 0.05) for SUL vs. HYD heifers. Effects of treatment × day were detected (P = 0.02) for plasma concentrations of insulin-like growth factor 1 (IGF-1) and haptoglobin. Plasma concentrations of IGF-1 were greater (P ≤ 0.05) for HYD vs. SUL heifers on days 56, 70, 77, 84, and 91. Plasma concentration of haptoglobin was greater (P = 0.05) for SUL vs. HYD heifers on day 63. Effects of treatment × day of the study and treatment were not detected (P ≥ 0.35) for plasma concentrations of cortisol, ß-hydroxybutyrate (BHBA) and non-esterified fatty acids (NEFA). Thus, Nelore heifers offered hydroxychloride sources of Cu, Mn, and Zn exhibited greater plasma concentrations of IGF-1 and a temporary increase in ADG during nutrient surplus compared to those receiving sulfate sources. While hydroxychloride supplementation reduced the acute phase response early in nutrient restriction, it did not improve growth and plasma concentrations of haptoglobin, cortisol, NEFA, and BHBA during nutrient restriction and adaptation to a high-starch diet.

This study investigated how 2 sources (sulfate vs. hydroxychloride) of copper, manganese, and zinc affect the growth and plasma indicators of inflammation and energy metabolism of Bos indicus beef heifers under various nutritional challenges. Nelore heifers were monitored through different periods of 28 d each: pen acclimation (days 0 to 28) = free access to hay and salt; nutrient surplus (days 28 to 56) = hay and protein supplement added with sulfate or hydroxychloride sources of copper, manganese, and zinc; nutrient restriction (days 56 to 84) = 50% of previous hay intake and supplementation of their respective treatment; and step-up adaptation period to a high-starch diet (days 84 to 112) = starch-rich diet containing their respective treatment. Heifers receiving hydroxychloride had greater growth performance and plasma concentrations of insulin-like growth hormone factor 1 during nutrient surplus and restriction phases compared to those receiving sulfate. Hydroxychloride supplementation reduced an inflammation marker during the nutrient restriction period, but it did not influence heifer growth during subsequent stages. Overall, while hydroxychloride reduced inflammation during nutrient restriction, it did not impact growth or plasma indicators of inflammation and energy metabolism during nutrient restriction and adaptation to a high-starch diet.

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Hibiscus sabdariffa (HS) extract contains a large amount of bioactive compounds with antioxidant, anticarcinogenic, and antihypertensive effects. The extraction of total phenols, flavonoids, and anthocyanins is more efficient at boiling temperature (~91 °C) than that performed at room temperature (~27 °C). In this study, a central composite rotatable design (CCRD) was used to optimize the inlet temperature conditions of a spray dryer and the concentration of taro starch solids to obtain microcapsules with the highest retention of bioactive compounds in hibiscus extracts. Optimized microcapsules (OM) were obtained at an inlet temperature of 118 °C and solid concentration of 26.5 %. Low moisture content (4.54 %) and water activity (0.2) and high content of total phenols (3374.91 mg GAE/100 g), flavonoids (372.81 mg QE/100 g), monomeric anthocyanins (36.74 mg C-3-GE/100 g), and angiotensin-converting enzyme inhibitory activity (80.01 %), were determined in OM using response surface methodology. OM showed a range of spherical agglomerate sizes (10--32 µm). These results indicate that CCRD is a good tool for establishing the optimal conditions for solid concentration and drying temperature to maximize the protection of bioactive compounds using taro starch as the wall material.

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Controlled release of beneficial microorganisms in agriculture by encapsulation in biopolymeric matrices can improve biofertilizer efficacy, but it requires the modulation of properties to ensure more efficient and predictable release patterns. This study investigated the effect of a starch-based system to protect and release Priestia megaterium (former Bacillus megaterium) processed as films modified with potential cell-protective additives (maltodextrin, cellulose, and bentonite). The release kinetics, physicochemical and morphological film characteristics, and their protection against UV (Ultraviolet) radiation and temperature were evaluated. The microorganism release was dependent of the film microstructure and composition, both in initial and extended-release rates. Maltodextrin incorporation increased cell release, while cellulose and bentonite delayed due to influences in the water uptake (swelling) and diffusion across polymer structure. Modified films protected the microorganisms against UV radiation and extreme temperatures, being the film with all additives (SMCB) the best protective formulation (100 % UVC survival) compared to starch matrix (< 20 % UVC survival after 40 min) and the one with the highest viability at higher (54 % survival at 45 °C) and lower (80 % survival at 15 °C) temperatures. These insights pave the way for targeted, efficient, and sustainable biological solutions to agricultural practices, aligning with evolving needs in modern agriculture.

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Olive pomace (OP) waste, produced in large quantities, contains significant amounts of cellulose and fibers, making it a valuable resource for developing reinforcing ingredients in biodegradable packaging materials. This study aimed to produce nanofibers from OP using enzymatic hydrolysis with hemicellulases and cellulases, and to incorporate these nanofibers into starch films as a reinforcing agent. Cellulose nanofibers (CNFs) were prepared by alkaline pretreatment followed by enzymatic hydrolysis (with hemicellulases and cellulases) from olive pomace and applied as reinforcement in starch films in concentrations of 0.5%-5% (w/v). The nanofibers were analyzed according to composition, structural, and thermal properties. The nanofibers' suspension presented a cloudy and white color in aqueous suspension, the X-ray diffraction (XRD) analysis showed the increase of crystallinity, and the fibers' range was no wider than 100 nm (according to Scherer equation). The composition analysis showed the decrease of carbonyl groups of hemicellulose and lignin. The starch films presented a homogenous surface. The solubility from these biodegradable films significantly reduced after the incorporation of CNF, and the nanomaterial's presence improved the degradation temperature (from 310°C to 322°C) and the mechanical resistance because the tension of rupture increased from 3.79 to 6.21 MPa. PRACTICAL APPLICATION: The utilization of waste from the olive pomace for cellulose nanofiber production holds promise, given the nanofibers' ability to readily integrate into various materials, including starches used in biodegradable film production. Within these matrices, nanofibers act as structure reinforcers and significantly reduce the solubility of films. Although biodegradable films ensure the shelf life, safety, and quality of food, their properties currently do not match those of traditional petroleum-based materials at an industrial scale, indicating a need for further enhancement.

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The amylose content can significantly impact the diverse industrial applications of cassava starch. This study aimed to assess the variability of cassava germplasm concerning amylose content and other attributes pertinent to root quality, alongside its correlation with paste properties. Starch extracted from 281 genotypes, obtained in germplasm evaluation trials, was evaluated for amylose content, with additional analysis of parameters such as pasting temperature, time to peak viscosity (TPV), viscosity breakdown (BrD), retrogradation tendency, and maximum, minimum, and final viscosities. The genotypes exhibited considerable variation in dry matter content (ranging from 27.06% to 41.02%), starch content (from 14.61% to 25.67%), cyanogenic compounds (1.77 to 7.81), and amylose content (0.05% to 33.23%). High phenotypic variability in paste properties was observed, alongside a low residual effect for most traits, resulting in high broad-sense heritabilities (>0.95). Strong correlations of significant magnitude (>0.80) were found between parameters such as peak viscosity × viscosity breakdown, minimum viscosity × final viscosity, and final viscosity × retrogradation tendency. Moderate correlations were also identified, such as between dry matter content × starch content (0.56). While positive, correlations between amylose content and paste properties were of low magnitude (ranging from 0.13 to 0.35), except for TPV and BrD. Principal component discriminant analysis clustered the germplasm into six distinct groups based on root quality and paste properties, with most improved genotypes falling into two clusters characterized by high starch and dry matter contents. This study underscores the necessity of simultaneous evaluation of amylose content and paste properties in the breeding pipeline. Additionally, clustering cassava genotypes proves beneficial in identifying those that fulfill specific requirements in industrial and breeding applications.

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Starch structure determination is crucial for understanding its properties and applications. However, method-dependent variations in size determination can lead to ambiguous interpretations. This study investigates the ambiguities in starch structure determination by evaluating the variation in size of four commercial branched starches as determined by average molar mass, gyration radius, hydrodynamic radius, and chain-length distribution. The starches were analyzed using high-performance size-exclusion chromatography (HPSEC) coupled with multi-angle laser light scattering (MALLS) and refractive index detector (RI), and after debranching by HPSEC-RI and high-performance anion-exchange chromatography (HPAEC) with pulsed amperometric detector (PAD). MALLS-derived MW values for amylose and amylopectin were higher than those obtained using the hydrodynamic volume method. The molecular weight of amylopectin chains, determined by the degree of polymerization (DP), ranged between 2.1 and 2.9 × 103 g/mol for short chains, and between 4.1 × 103 and 1.1 × 104 g/mol for long chains. Differences in amylopectin chain content were observed between HPSEC-RI and HPAEC-PAD, highlighting the complementary nature of these techniques. The study underscores the need for standardizing chromatography-based methodologies in starch research, particularly with the advent of new technologies.

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The industrial use of corn starch competes with food supplies, encouraging the investigation of native starches as an alternative for its partial replacement. This study aimed to analyze the effects of replacing corn starch (CS) with wolf's fruit (WFS) and butterfly lily (BLS) starches on the physicochemical, mechanical, and biodegradation properties of starch-based films. Plasticized (with glycerin and citric acid) and unplasticized films were prepared with a microwave (10 s) and by thermopressing (1.5 t/120 °C/2 min) and were analyzed for amylose, scanning electron microscopy, X-ray diffraction, and paste properties. Furthermore, the biodegradability of films was tested in two soils over 42 days. Our results show that BLS is not a suitable raw material to replace corn starch. WFS with 27.5 % apparent amylose content and granule size of 12.5 µm produced films with thickness, permeability, tensile strength, and elongation of ~110 µm, ~4.8 g (m.s.Pa)-1, ~2.5 MPa, and ~2.9 %, respectively, similar to CS. The biodegradability of WFS film showed greater resistance (≤61.4 %), increasing with the addition of plasticizers (89-93 % for WFS302) or partial replacement of CS (73-91 % for CSWFS303). These findings indicate that WFS can partially or fully replace CS in thermopressed films.

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This study aimed to investigate the effects of acid or alkali modification of isolated cassava starch (ICS) on its physicochemical properties. Acetic acid concentrations of 5%, 10%, and 20% v/v (0.87, 1.73, and 3.46 M, respectively) and calcium hydroxide concentrations of 0.15%, 0.20%, and 0.30% w/w (0.02, 0.025, and 0.04 M, respectively) were tested independently and compared with untreated isolated starch. The scanning electron microscope (SEM) shows starches with polyhedral and semispherical shapes; these modifications do not change the surface of the starch granules. Nanocrystals with orthorhombic crystal structure were extracted from ICS. Transmission electron microscopy (TEM) shows crystallites with a size (two-dimensional) of 20 ± 5 nm in length and 10 ± 2 nm in width and reveals that this starch contains nanocrystals with orthorhombic crystal structure. The X-ray patterns show that these nanocrystals are unaffected by acidic or alkaline treatments. The Ca+2 and CH3COO- ions do not interact with these nanocrystals. The alkaline treatment only affects the gelatinization temperature at a Ca(OH)2 concentration of 0.30%. Low concentrations of acidic and alkaline treatments affect the ability of cassava starch to absorb water and reduce the peak and final viscosity. The infrared spectra show that the modifications lead to C-H and C═C bond formations. ICS-B 0.30 can modify the amorphous regions of the starch, and the acid treatment leads to acetylation, which was confirmed by the presence of an IR band at 1740 cm-1.

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The use of biopolymers as an alternative to petroleum-based polymers offers a sustainable solution with benefits such as biodegradability and unique functionalities. In this study, starch/zein bioparticles (BPs) obtained by nanoprecipitation were employed to synthesize acrylic polymer/biopolymer waterborne nanoparticles with excellent film formation capability. These hybrid nanoparticle dispersions were obtained through a semibatch emulsion polymerization using the previously synthesized BPs as seed and variable monomeric formulations composed of butyl acrylate and methyl methacrylate. A synergetic effect between acrylic and biopolymer phases was evidenced where the incorporation of BPs had a fundamental role in improving sensitive properties, such as film blocking resistance, while attaining smooth films at room temperature. These excellent film-forming properties of starch/acrylic hybrid latexes without requiring the addition of formulation agents, which depict an important benefit from an environmental viewpoint, demonstrate that they represent a promising alternative for the development of a new generation of eco-friendly binders.

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Aiming to contribute to the current knowledge on the impact of reaction conditions on the chemical structure and target properties of starch citrates, in the current contribution different corn starch citrates were prepared by manipulation of reaction time, temperature and citric acid concentration. Modified starches were characterized in terms of chemical structure, morphology, crystallinity, swelling power and resistant starch content. For the first time, total substitution, crosslinking and monosubstitution degrees were quantitatively determined; and the relationship among final chemical structure, reaction conditions and target starch citrates properties was comprehensively analyzed. Products with total substitution values in the range of 0.075-0.24, crosslinking degrees in the 0.005-0.11 interval, and monosubstitution extents within the 0.05-0.12 range, were produced. By proper selection of reaction conditions products with almost 100 % of resistant starch were obtained. Results evidenced that starch citrates properties (mainly swelling power and RS content) depend on both chemical structure and the reaction conditions employed. Actually, the reaction temperature set (120 °C or 150 °C) proved to play a determinant role in the final products properties as evidenced from starch citrates with similar chemical structure and substantially different swelling and digestibility properties.

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Using green techniques to convert native starches into nanoparticles is an interesting approach to producing stabilizers for Pickering emulsions, aiming at highly stable emulsions in clean label products. Nanoprecipitation was used to prepare the Pickering starch nanoparticles, while ultrasound technique has been used to modulate the size of these nanoparticles at the same time as the emulsion was developed. Thus, the main objective of this study was to evaluate the stabilizing effect of cassava starch nanoparticles (SNP) produced by the nanoprecipitation technique combined with ultrasound treatment carried out in the presence of water and oil (more hydrophobic physicochemical environment), different from previous studies that carry out the mechanical treatment only in the presence of water. The results showed that the increased ultrasound energy input could reduce particle size (117.58 to 55.75 nm) and polydispersity (0.958 to 0.547) in aqueous dispersions. Subsequently, Pickering emulsions stabilized by SNPs showed that increasing emulsification (ultrasonication) time led to smaller droplet sizes and monomodal size distribution. Despite flocculation, long-term ultrasonication (6 and 9 min) caused little variation in the droplet size after 7 days of storage. The cavitation effects favored the interaction between oil droplets through weak attraction forces and particle sharing, favoring the Pickering stabilization against droplet coalescence. Our results show the potential to use only physical modifications to obtain nanoparticles that can produce coalescence-stable emulsions that are environmentally friendly.