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New botanical materials are emerging as unconventional sources of starch, increasing their economic value and, therefore, providing a higher starch demand with novel and unique properties for the substitution of traditional starch sources. Overall, starch isolation from roots and tubers is simple and based on breaking vegetal cells to release the starch. Starch extraction from pulses is more complex due to their higher protein and lipid content and smaller starch granules compared to roots and tuber starches. Starch from pseudocereals can be isolated by wet milling. Recently, alternative sources of starch have been proposed, including tree, herbs/shrubs, and fruits; the isolation of starch from these sources involves wet milling procedures in the presence or absence of the chemical solutions. This review summarizes the usual laboratory methods and recent advances in the extraction of starches from roots, tubers, pulses, and pseudocerals. Starch extraction methods from unconventional sources are also described. This review may be useful to guide researchers and technologists from the industry in their choice of better starch extraction methods, presenting the advantages and disadvantages of each method. [ABSTRACT FROM AUTHOR]

During oxidation, the hydroxyl groups of starch molecules are first oxidized to carbonyl groups, then to carboxyl groups. The contents of the carbonyl and carboxyl groups in a starch molecule therefore indicate the extent of starch oxidation. The mechanisms of starch oxidation with different oxidizing agents, including sodium hypochlorite, hydrogen peroxide, ozone and sodium periodate, are described in this review. The effects of these oxidizing agents on the molecular, physicochemical, thermal, pasting and morphological properties of starch are described as well. In addition, the main industrial applications of oxidized starches are presented. The present review is important for understanding the effects of oxidation on starch properties, and this information may facilitate the development of novel oxidized starches for both food and non-food applications. [ABSTRACT FROM AUTHOR]

BACKGROUND Biodegradable films of native or acetylated starches with different concentrations of cellulose fibers (0%, 10% and 20%) were prepared. The films were characterized by morphological, mechanical, barrier, and thermal properties. RESULT The tensile strength of the acetylated starch film was lower than those of the native starch film, without fibers. The addition of fibers increased the tensile strength and decreased the elongation and the moisture of native and acetylated starches films. The acetylated starch film showed higher water solubility when compared to native starch film. The addition of cellulose fibers reduced the water solubility of the acetylated starch film. The films reinforced with cellulose fiber exhibited a higher initial decomposition temperature and thermal stability. CONCLUSION The mechanical, barrier, solubility, and thermal properties are factors which direct the type of the film application in packaging for food products. The films elaborated with acetylated starches of low degree of substitution were not effective in a reduction of the water vapor permeability. The addition of the cellulose fiber in acetylated and native starches films can contribute to the development of more resistant films to be applied in food systems that need to maintain their integrity. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Proteins have been used extensively because of their relative abundance, nutritional qualities, and film-forming ability with a good structural integrity and mechanical properties. This study investigated the effects of protein isolate and glycerol concentration and pH on the properties of protein films obtained from Whitemouth croaker (Micropogonias furnieri) residues. The films were evaluated for mechanical properties, thickness, water solubility, water vapor permeability (WVP), and morphological properties. The lowest water solubility of the films occurred at low pHs and low glycerol concentrations. The films had high elongation and higher tensile strength when prepared with higher concentrations of protein isolate, lower concentrations of glycerol, and at lower pHs. The WVP and thickness of the films had a low correlation coefficient. The films were rough and had irregular surfaces. These results indicated that protein isolates from fish of low commercial value can be used as a component of new polymeric films for packaging. However, more studies are needed to assess their barrier action against oxygen, thermal behaviors, and their performance in different types of packaging. [ABSTRACT FROM PUBLISHER]

Starch and cellulose fibers were isolated from grains and the husk from barley, respectively. Biodegradable films of native starch or oxidized starches and glycerol with different concentrations of cellulose fibers (0%, 10% and 20%) were prepared. The films were characterized by morphological, mechanical, barrier, and thermal properties. Cellulose fibers isolated from the barley husk were obtained with 75% purity and high crystallinity. The morphology of the films of the oxidized starches, regardless of the fiber addition, was more homogeneous as compared to the film of the native starch. The addition of cellulose fibers in the films increased the tensile strength and decreased elongation. The water vapor permeability of the film of oxidized starch with 20% of cellulose fibers was lower than the without fibers. However the films with cellulose fibers had the highest decomposition with the initial temperature and thermal stability. The oxidized starch and cellulose fibers from barley have a good potential for use in packaging. The addition of cellulose fibers in starch films can contribute to the development of films more resistant that can be applied in food systems to maintain its integrity. [ABSTRACT FROM AUTHOR]

The degree of acetylation controls the use of starch acetate, since the FDA (Food and Drug Administration USA) recommends an acetyl groups' percentage below 2.5 g/100g for a food application. The objective of this work was to evaluate the effects of the acetic anhydride concentration, in an aqueous solution, on the degree of acetylation, in physical, thermal, pasting and morphological properties, and enzymatic susceptibility on rice starch acetylated with the acetyl groups' percentage up to 2.5 g/100g. The rice starch was acetylated using different concentrations of acetic anhydride (5 g/100g, 10 g/100g and 20 g/100g, starch db). Acetylation increased the peak viscosity, breakdown, final viscosity, retrogradation and pasting temperature and reduced the hardness of the gels, as well as their adhesiveness and gumminess; however this did not affect the morphology and susceptibility to hydrolysis by the α-amylase of the starch. The acetylated starches using 10 and 20 g/100g acetic anhydride showed lower swelling power and solubility compared to native starch. [ABSTRACT FROM AUTHOR]

The versatility of starch products is such that they are used as ingredients and functional supplements in a variety of food, nonfood, and feed applications. As starch is the largest constituent of cereal grains, there is an increasing interest in the isolation of the product from starch sources. Besides that, cereals are the main raw material used for the isolation and extraction of starch. The method of cereal starch isolation is influenced mainly by protein solubility, the level of protein–starch interaction, and characteristics of the starch granules. This review discusses traditional methods as well as recent advances in the extraction of cereal starches. The present review is important for understanding the effects of the particular characteristics of each cereal source in the starch extraction, including the size and morphology of starch granules, the composition of proteins with different solubilities, and protein–starch interactions. This information may avoid waste of reagents and unnecessary steps and facilitate the starch extraction process [ABSTRACT FROM AUTHOR]

The cover image, by Shanise Lisie Mello El Halal et al., is based on the Research Paper Morphological, mechanical, barrier and properties of films based on acetylated starch and cellulose from barley, DOI: . [ABSTRACT FROM AUTHOR]

Wheat starch is modified by phosphorylation and cross‐linking. Starches are evaluated for phosphorus content, amylose content, swelling power, solubility, pasting properties, crystallinity, and morphology. Films are made with phosphorylated and cross‐linked starches, and with addition of 10% (w/w) polyethylene oxide (PEO). The films are evaluated for morphology, water vapor permeability, mechanical properties, crystallinity, roughness, and angle of contact with water. Phosphorylated starch shows higher phosphorus content, amylose content, swelling power, and solubility than cross‐linked starch and native starch did. The starch film containing PEO presents discontinuous morphology, is more crystalline and rugged, and less hydrophilic than starch films without PEO. The biocomposite proves promising for usage in flexible packaging. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: pH‐sensitive indicator membranes, which are useful for pharmaceutical, food, and packaging applications, can be formed by encapsulating halochromic compounds within various solid supports. Accordingly, electrospinning is a versatile technique for the development of these indicators, by entrapping pH dyes within ultrafine polymer fibers. RESULTS: The ultrafine zein fibers, containing 5% (w/v) anthocyanins, had an average diameter of 510 nm. The pH‐sensitive membrane exhibited color changes from pink to green when exposed to acidic and alkaline buffers, respectively. The contact angle was negligible after 10 and 2 s for neat and 5% anthocyanin‐loaded zein membranes, respectively. CONCLUSION: The pH membranes exhibited color changes in a board pH range, which can potentially be used in various active packaging applications. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The present study aims to evaluate the impact of black bean moisture content and storage temperature on the crystallinity, thermal, pasting, and morphological properties of isolated starch. Starch was extracted from black beans stored with 14 and 17% moisture content at 11, 18, 25, and 32°C for 12 months. The results showed that the moisture content and the storage temperature affect the characteristics of the starch. Major changes were observed in starch obtained from beans stored at 17% moisture content and 32°C, exhibiting increased swelling power, peak and breakdown viscosities, and decreased solubility, relative crystallinity, enthalpy of gelatinization (ΔH), and final and setback viscosities. The main changes occurring in starch granules during storage of black beans appear to be located in the crystalline domains of the granules. The low final and setback viscosities determined in the starch from beans stored at 17% moisture content and 32°C suggest that this material can serve as a potential ingredient to be used in frozen and chilled products, where stability at low temperatures is desired. [ABSTRACT FROM AUTHOR]

Biodegradable films from native or acetylated starches with different amylose levels were prepared. The films were characterized according to the mechanical, water vapor barrier, thermal, and biodegradability properties. The films from acetylated high amylose starches had higher moisture content and water solubility than the native high amylose starch film. However, the acetylation did not affect acid solubility of the films, regardless of the amylose content. Films made from high and medium amylose rice starches were obtained; however low amylose rice starches, whether native or acetylated, did not form films with desirable characteristics. The acetylation decreased the tensile strength and increased the elongation of the films. The acetylated starch-based films had a lower decomposition temperature and higher thermal stability than native starch films. Acetylated starches films exhibited more rapid degradation as compared with the native starches films. [ABSTRACT FROM AUTHOR]

Highlights: [•] Low-amylose rice starch was more susceptible to acetylation. [•] Acetylated starches presented hydrophobic characteristics. [•] The crystallinity and viscosity decreased with acetylation, mainly in 90-min of reaction. [ABSTRACT FROM AUTHOR]

Natural fermentation with sun-drying is a modification that promotes the expansion capacity of starch, and its effects on potato starch have not been reported so far. The aim of this study was to evaluate the effects of the amylose content of potato (Solanum tuberosum L.) starches and natural fermentation followed by oven or sun drying on its properties. Cassava starch was also used a control. Native and fermented starches were evaluated based on their chemical composition, amylose, carboxyl and carbonyl content as well as their thermal, pasty, and morphological properties. The fermentation water was evaluated by pH and titratable acidity to control the process. Puffed balls were prepared to evaluate expandability, mass loss, porosity and texture. The fermentation intensity was greater for potato and cassava starch with low-amylose content than for potato starch with higher amylose content. In addition, the acidity of the fermentation water increased faster with cassava starch than with potato starches. The fermented potato starches with the highest amylose content had low acidity and low expansion capacity compared to the fermented potato and cassava starches with low-amylose content. Fermentation and sun-drying of low-amylose potato and cassava starches increased the expansion and reduced the hardness of the puffed balls. • Low-amylose starch had more intense fermentation than high-amylose starches. • Fermentation and sun-drying decreased the viscosity of high-amylose potato starches. • Fermentation and sun-drying processes improved the expansion properties of starches. • Biscuits with low-amylose starches presented the highest expansion. • Biscuits with sun-dried, low-amylose potato starch were the least hardness. [ABSTRACT FROM AUTHOR]

BACKGROUND: Starches from four common bean genotypes were characterized and used in the production of biodegradable films. Starches were characterized by their swelling power, solubility, amylose content, granule morphology, relative crystallinity, thermal and pasting properties, and susceptibility to α‐amylase hydrolysis. Films were characterized according to their morphology, mechanical and water vapor barrier properties, whiteness and opacity. RESULT: Depending on the common bean genotype, a great variation on starch properties was found, which, in turn, clearly impacted on the characteristics of the starch‐based films. Starches from BRS Pitanga and BRS Pérola genotypes exhibited the highest amylose content and the lowest swelling capabilities. Bean starch from the IPR Uirapuru genotype presented granules with an irregular surface and shape. Starches from IPR Uirapuru and BRS Estilo genotypes provided well‐structured biodegradable films, without the occurrence of fissures or cracks. Moreover, starch films containing starch from BRS Estilo genotype exhibited the highest flexibility, permeability and solubility. CONCLUSION: The morphological, mechanical and water vapor barrier properties of films elaborated with common bean starch vary greatly as a function of the bean genotype used for starch production. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the physicochemical, morphological, crystallinity, thermal, and pasting properties of starches isolated from rice grains with brown, black, and red pericarp. Starch was isolated from the rice grains at initial storage time, and after 6 months of storage at different storage temperatures (16, 24, 32 and 40 °C). Starch isolated from the grains stored for 6 months at 40 °C showed darker coloration, surface deformation of granules, and a significant reduction in the extraction yield, final viscosity, enthalpy, and crystallinity, independent of the grain pericarp coloration. The time and storage temperature not influence the swelling power and solubility of starch isolated from grains with brown pericarp, while for the grains with black and red pericarp there was reduction in swelling power and solubility of starches isolated of grains stored at 40 °C. Grains stored at 16 °C showed minimum changes in starch properties. [ABSTRACT FROM AUTHOR]

Pinhão starch was modified by annealing (ANN), heat-moisture (HMT) or sonication (SNT) treatments. The starch was also modified by a combination of these treatments (ANN–HMT, ANN–SNT, HMT–ANN, HMT–SNT, SNT–ANN, SNT–HMT). Whole starch and debranched starch fractions were analyzed by gel-permeation chromatography. Moreover, crystallinity, morphology, swelling power, solubility, pasting and gelatinization characteristics were evaluated. Native and single ANN and SNT-treated starches exhibited a CA-type crystalline structure while other modified starches showed an A-type structure. The relative crystallinity increased in ANN-treated starches and decreased in single HMT- and SNT-treated starches. The ANN, HMT and SNT did not provide visible cracks, notches or grooves to pinhão starch granule. SNT applied as second treatment was able to increase the peak viscosity of single ANN- and HMT-treated starches. HMT used alone or in dual modifications promoted the strongest effect on gelatinization temperatures and enthalpy. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the effects of sodium hypochlorite oxidation and a heat–moisture treatment of potato starch on the physicochemical, pasting and textural properties of potato starches in addition to the water vapour permeability (WVP) and mechanical properties of potato starch films produced from these starches. The carbonyl contents, carboxyl contents, swelling power, solubility, pasting properties and gel texture of the native, oxidised and heat–moisture treated (HMT) starches were evaluated. The films made of native, oxidised and HMT starches were characterised by thickness, water solubility, colour, opacity, mechanical properties and WVP. The oxidised and HMT starches had lower viscosity and swelling power compared to the native starch. The films produced from oxidised potato starch had decreased solubility, elongation and WVP values in addition to increased tensile strength compared to the native starch films. The HMT starch increased the tensile strength and WVP of the starch films compared to the native starch. [Copyright &y& Elsevier]

Wheat pre‐harvest sprouting (PHS) is caused by high rainfall especially when the grain is in the filling stage. PHS decreases the grain yield, and is harmful to flour technological quality for baking, with a consequent decrease in economic value. However, the amylolytic activity promoted by germination can facilitate the production of cyclodextrin (CDs). The influence of germinated wheat starch concentration (1% and 10%) on the production of α, β, and γ‐CD is verified. In addition, the thermal stability of the inclusion complex between CDs produced from germinated wheat starch and orange essential oil (CDs/OEO) is also evaluated. The germination promotes the highest conversion yield (54.4%) at the lowest starch concentration (1%) used. The CDs/OEO increase the orange essential oil thermal stability, promoting their protection at high temperatures. Therefore, this study shows that germinated wheat starch is a promising substrate for the cyclodextrin production, adding value to this product that is, normally, not used by the food industry, but for animal nutrition or discarded. [ABSTRACT FROM AUTHOR]

• The orange essential oil has activity against S. aureus and L. monocytogenes. • Starch films with orange essential oil have activity against L. monocytogenes. • Starch films incorporated with orange essential oil have activity against S. aureus. • Starch films with orange essential oil have potential for use as bioactive films. • Orange essential oil increased the moisture, water solubility, and PWV of the films. The incorporation of antimicrobial compounds into natural polymers can promote increased shelf life and ensure food safety. The aim of this study was to evaluate the antibacterial activity, morphological, optical, mechanical, and barrier properties of corn starch films containing orange (Citrus sinensis var. Valencia) essential oil (OEO). The corn starch films were prepared using the casting method. OEO and the corn starch films incorporated with OEO showed higher antibacterial activity against Staphylococcus aureus and Listeria monocytogenes. The addition of OEO to the films increased the morphological heterogeneity and contributed to the reduction of the tensile strength and elongation of the films, and it increased the moisture content, water solubility, and water vapor permeability. The water vapor permeability and partial or total solubility of a film in water prior to consumption of a product are of interest when the film is used as food coating or for encapsulation of specific molecules. [ABSTRACT FROM AUTHOR]