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White and red cocoyam starches were physically modified by heat moisture treatment at 16, 24 and 32 % moisture levels. The functional and pasting properties of the modified and native starches were evaluated using standard methods. The swelling power at 60oC, water absorption capacity, oil absorption capacity, least gelation concentration, packed bulk density and loose bulk density of heat moisture treated white and red cocoyam starches ranged between 1.90 - 2.18 and 1.89 – 2.21; 1.00 – 1.80 ml/g and 0.80 – 1.60 ml/g; 1.40 – 1.80 ml/g and 1.20 – 1.40 ml/g; 8.00 – 10.00% and 8.00 – 10.00%; 0.51 – 0.62 g/ml and 0.54 – 0.64 g/ml; 0.41 – 0.51 g/ml and 0.43 – 0.53 g/ml respectively. For both white and red cocoyam starches, heat moisture treated starches at 16% moisture content level had the highest swelling power in the temperature range 60oC to 90oC; also starches treated at 32% moisture level had the highest water absorption capacity, oil absorption capacity, packed bulk density and loose bulk density. Red cocoyam native starch had higher peak, trough, breakdown, final and setback viscosity than white cocoyam starch. Heat moisture treatment generally increased the pasting properties of white cocoyam starch. The modification of red cocoyam starch at moisture levels of 16% and 24% reduced the pasting properties, however at higher moisture level, the pasting properties increased. These results suggest that moisture level of cocoyam starches influence their physicochemical properties during heat moisture modification; this will increase the array of food products in which the starches can be used.

Ultrasound technique was used to produce native and acetylated cassava starch particles containing potassium sorbate (KS). In order to obtain an active packaging, films with addition of native starch particles containing KS (NKSPF) or added with acetylated starch particles containing KS (AKSPF) were formulated. As control systems, films without KS (CF) or added with KS that was not retained in particles (KSF), were produced. The NKSPF and AKSPF microstructure was consistent with composite materials. Tensile test revealed that CF and KSF were ductile and extensible (stress at break (σb) 2.8–2.5 MPa and strain at break (εb) 284–206%), while NKSPF and AKSPF were more resistant films with higher Young’s Modulus (148–477 MPa) and σb (3.6–17 MPa) but lower εb (40–11%). Moreover, NKSPF and AKSPF developed lower Yellowness Index (6.6–6.5) but higher opacity (19–23%) and solubility in water (31–35%) than KSF (9, 10.8% and 9%, respectively). It was observed that KSF and NKSPF moderately reduced the Zygosaccharomyces bailii growth while AKSPF showed the highest yeast inhibition, three Log-cycles, compared to CF. Additionally, FTIR spectroscopy revealed intensified interactions between KS and modified starch. It was concluded that starch sonication and acetylation were useful modifications to produce particles carrier of KS that improved the physical and antimicrobial performance of active films.

Several methods are currently employed in the modification of starch obtained from different botanical sources. Starch in its native form is limited in application due to retrogradation, syneresis, inability to withstand shear stress as well as its unstable nature at varying temperatures and pH environment. Modification of starch is therefore needed to enhance its food and industrial application. A primary and safe means of modifying starch for food and industrial use is through hydrothermal methods which involves heat-moisture treatment and annealing. Heat-moisture treatment (HMT) is a physical modification technique that improves the functional and physicochemical properties of starch without changing its molecular composition. Upon modification through HMT, starches from cereals, legumes and tuber crops serve as important ingredients in diverse food, pharmaceutical and industrial processes. Although changes in starch initiated by HMT have been studied in starches of different plant origin, this work further provides insight on the composition, thermal and functional properties of heat-moisture treated starch obtained from cereals, legumes and tuber crops.

This study focused on the effect of cycled heat-moisture treatment (cHMT) on the in vitro digestibility, rheological, and physicochemical properties of water caltrop starch. The amylose content increased significantly by cHMT, whereas damaged starch content decreased only in the groups with more than two cycles applications. cHMT generally increased the weight-average molecular weight, except for single cycle treatment which showed the reverse result. In thermal properties, the onset temperature (T0), peak temperature (Tp), and conclusion temperature (Tc) increased, while the enthalpy needed to complete the gelatinization was lowered by cHMT. Water caltrop starch paste showed less shear-thinning behavior with cHMT. Meanwhile, the viscosity and tendency to form strong gel were enfeebled with modification. cHMT significantly changed predicted glycemic index (pGI) value, especially in samples that underwent the most cycles of treatment, which showed the lowest pGI compared to native and other treatment. These results suggested that cHMT water caltrop starch was effectively modified and showed diversified properties.

Ozone is an interesting alternative for modifying starch, as it is considered an emerging and environmentally friendly technology. New applications for food ingredients are receiving attention, such as 3D printing. Consequently, the impact of emerging technologies on new applications must be understood. In this work, cassava starch was modified by ozone to evaluate its printability. Increasing ozonation time produced a starch with higher carbonyl and carboxyl contents, lower pH and molecular size, and gels with different behaviors (stronger and weaker than the native ones, as a function of processing time). The hydrogels obtained were evaluated in relation to pasting and gel properties, including their printability. The effects of starch concentration, gelatinization temperature and storage period were also evaluated. Starch ozonated for 30 min showed the lowest peak apparent viscosity at all the temperatures and starch concentrations evaluated, and provided the strongest gel. Gels produced by native starches and starches ozonated for 30 min showed good printability when the gelatinization temperature used was 65 °C, but up to this temperature, only starch ozonated for 30 min produced gels with good printability. This work highlights that, by using the ozone process to modify starch and varying the process conditions, it is possible to obtain hydrogels with enhanced pasting properties, gel texture, and printability, thereby expanding the potential of starch applications.

International audience; This work evaluated the impact of PEF on the structure, properties, and functionality of wheat and cassava starches focusing on 3D printing application. Aqueous starch suspensions were PEF-treated using three different combinations of field strength and total specific energy input (T1:15 kV/cm;25 kJ/kg; T2:25 kV/cm;25 kJ/kg; and T3:25 kV/cm;50 kJ/kg). The three conditions had the same effect on cassava starch (no damage on granules surface, reduction of peak apparent viscosity, firmer gels), while T3 promoted a greater effect on wheat starch (fractures on granules surface, reduction in peak apparent viscosity, and firmer gels). T3 condition was selected for further evaluation, revealing depolymerization, reduction of relative crystallinity, and gelatinization enthalpy, but no changes in functional groups. PEF-treated wheat starch resulted in 3D printing with a smoother surface and different texture, while PEF-treated cassava starch showed the same performance of native starch. Therefore, PEF affects differently each source, potentially enhancing 3D printing applications.

International audience; This work evaluated for the first time the effect of dual modification of cassava starch by using ozone (O-3) and dry heating treatment (DHT). The dual modification was capable to promote fissures on the surface of the starch granule (DHT + O-3), affected the starch amorphous domains, presented greater degree of starch oxidation (DHT + O-3) and different profiles of starch molecular size distribution. These modifications resulted in starches with different properties. Moreover, the sequence of treatments was decisive for the hydrogel properties: while DHT + O-3 resulted in formation of stronger gels, O-3 + DHT resulted in weaker gels. In conclusion, this proposed dual modification was capable to produce specific modified starch when compared with the isolated treatments, also expanding the potential of cassava starch applications. (C) 2020 Elsevier B.V. All rights reserved.

Ultrasound-assisted extraction (UAE) has been optimized to improve the current cassava starch production by conventional maceration for the extraction method. Evaluation of several extraction parameters disclosed significant effects (p < 0.05) by three studied factors (ultrasound power, x1; pulse duty-cycle, x2; and solvent to sample ratio, x3). Subsequently, a Box-Behnken design (BBD) in conjunction with response surface methodology (RSM) was employed to optimise the three factors at three levels: x1 (30, 60, 90%), x2 (0.3, 0.6, 0.9 s−1), and x3 (10:1, 20:1, 30:1). The model built for the RSM was validated through the coefficient of determination (R2 > 0.95), prediction error (2.12%), and lack-of-fit (0.71) values. The model validation suggested that the RSM was adequate for the observed data at the 95.0% confidence level. The optimum yield of cassava starch extraction was achieved by applying 90% for ultrasound power, pulse duty-cycle of 1.0 s−1, and solvent to sample ratio of 30:1 with 10 min extraction time. Finally, the UAE produced starch with a purity of 88.36% and a lower viscosity than the commercial sample due to the granules’ size alteration. Hence, apart from speeding up the extraction process, UAE was worthwhile for the starch modification that could maintain the viscosity at a lower value (1920 cP) than the commercial starch (1996 cP) at the highest studied temperature treatment of 70 °C.

Brazilian cheese bread (CB) rolls are gluten-free bread made from sour cassava starch. They are soft in the center and have crispy crust, reminding of the extruded structure. Although native waxy maize starch (WMS) has higher technologic quality, it has not been used in CB rolls; therefore, this study aimed to investigate the use of WMS and the backslopping fermentation process plus sun drying in WMS to replace sour cassava starch (0, 25%, 75%, and 100%) and the effects on dough development, color, and textural properties. Data were analyzed using variance and Tukey test (p ≤ 0.05%), and the results were set against a commercial product from cassava starch. The better formulation was characterized by proximal composition, sensorial acceptance, and willingness to buy, and data were presented as means and standard deviation. The different statistic parameters included color to redness coordinate, baking expansion capacity, specific volume, hardness, fracturability, and chewiness. The best formulation had 100% of sundried WMS and was microbiologically safe. The proximal composition had lower values than that obtained from the Brazilian Food Database. The product was considered satisfactory as it had a score of more than 7.79 to texture, appearance, and flavor with higher willingness to buy (92.5%). The backslopping fermentation plus SWMS was considered a potential replacement for sour cassava starch. RESUMO Pão de queijo (PQ) é um produto sem glúten, produzido a partir de amido de mandioca azedo. Apresenta casca crocante e miolo macio, lembrando uma estrutura extrudada. O amido de milho ceroso (AMC) é conhecido pela sua qualidade tecnológica e não foram encontrados estudos para sua aplicação na produção de PQ. Neste sentido o presente trabalho objetivou investigar o uso de AMC e de AMC fermentado, utilizando polvilho azedo de mandioca como inóculo, e seco ao sol (AMCF) na substituição do amido convencional (0, 25, 75, e 100%) e seus efeitos no desenvolvimento da massa, cor e propriedades de textura. Os dados foram analisados por ANOVA e teste de Tukey (p≤0.05%) e os resultados foram comparados com um produto comercial A melhor formulação foi caracterizada quanto sua composição proximal, aceitação sensorial e pela intenção de compra e os dados são apresentados pelas suas médias e desvio-padrão. Os parâmetros que diferiram estatisticamente foram as coordenadas de cor para o vermelho, capacidade de expansão, volume específico. Com 100% de AMCF a melhor formulação foi microbiologicamente segura. A composição proximal apresentou valores menores quando comparados com os valores da Tabela Brasileira de Composição de Alimentos. O produto pode ser considerado com boa aceitação, já que apresentou notas maiores que 7,79 para textura, aparência, sabor e intenção de compra. O AMCF pode ser considerado como um bom substituto para o polvilho azedo de mandioca.

Starch is a processed product from sweet potato widely used in foods product. However, in general native sweet potato starch has constrains that often inhibits its application in food products. Starch hydrothermal modification might overcome the problem. This study aimed to study the effect of hydrother-mal treatment on the physicochemical and functional characteristics of purple sweet potato starch. The study was conducted in two stages, i.e. modification of starch purple sweet potato variety antin-3 hydrothermally, i.e. using moisture content of 30, 50% and heating temperature of 55 and 75°C, and characterization of the physicochemical and functional properties of the modified starch. The yield of starch from purple sweet potato by wet extraction method was 16.81±1.48%. Hydrothermal treatment on the purple sweet potato starch did not alter the concentration of starch, amylose and amylopectin. The natural and hydrothermal starches had polygonal granular shape. The swelling power of the hydrothermal starch incubated at 75°C was higher than that of incubated at 55°C, while the hydrothermal starch solubility was lower than the natural starch. The natural and hydrothermal starches of purple sweet potato had an A-type starch gelatinization profile. Hydrothermal treatment of starch with 50% moisture content at 75°C could change the functional properties of starch, i.e increased the proportion of slowly digestible starch by 22%.

Starch is one of the most common biodegradable polymers found in nature, and it is widely utilized in the food and beverage, bioplastic industry, paper industry, textile, and biofuel industries. Starch has received significant attention due to its environmental benignity, easy fabrication, relative abundance, non-toxicity, and biodegradability. However, native starch cannot be directly used due to its poor thermo-mechanical properties and higher water absorptivity. Therefore, native starch needs to be modified before its use. Major starch modification techniques include genetic, enzymatic, physical, and chemical. Among those, chemical modification techniques are widely employed in industries. This review presents comprehensive coverage of chemical starch modification techniques and genetic, enzymatic, and physical methods developed over the past few years. In addition, the current applications of chemically modified starch in the fields of packaging, adhesives, pharmaceuticals, agriculture, superabsorbent and wastewater treatment have also been discussed.

This review discusses the use of starch in plant-based meat replacing products. Starch is often added to meat and meat replacing products as a functional ingredient. The function of starch in those applications is investigated to be able to describe how it affects the production and structuring process as well as product properties. Often modified starch is used in these products, because of its improved functionality compared to native starch. Next to that, starch can also be present in meat replacing products as part of other ingredients, for example, when using legume or cereal meals or concentrates. It is discussed if this endogenous starch can have similar functionality and if not, whether it can be modified in a similar way as industrially modified starch. A new perspective on endogenous starch is proposed, demonstrating options for in situ modifications and promoting the use of less-refined and therefore more sustainable ingredients in fibrous meat replacing products.

Amylomaltases (4-α-glucanotransferases, E.C. 2.4.1.25) are enzymes which can perform a double-step catalytic process, resulting in a transglycosylation reaction. They hydrolyse glucosidic bonds of α-1,4′-d-glucans and transfer the glucan portion with the newly available anomeric carbon to the 4′-position of an α-1,4′-d-glucan acceptor. The intramolecular reaction produces a cyclic α-1,4′-glucan. Amylomaltases can be found only in prokaryotes, where they are involved in glycogen degradation and maltose metabolism. These enzymes are being studied for possible biotechnological applications, such as the production of (i) sugar substitutes; (ii) cycloamyloses (molecules larger than cyclodextrins), which could potentially be useful as carriers and encapsulating agents for hydrophobic molecules and also as effective protein chaperons; and (iii) thermoreversible starch gels, which could be used as non-animal gelatin substitutes. Extremophilic prokaryotes have been investigated for the identification of amylomaltases to be used in the starch modifying processes, which require high temperatures or extreme conditions. The aim of this article is to present an updated overview of studies on amylomaltases from extremophilic Bacteria and Archaea, including data about their distribution, activity, potential industrial application and structure.

Starch is a very common carbohydrate. Along with its use in the pharmaceutical, textile, and paper industries, starch is widely used in the food industry as well, but native starch has limited use due to its certain properties such as retrogradation, problems related to gelatinization, instability at high temperatures, and acidic conditions. Various modification procedures are used to improve the properties of native starch. Along with consumer demands for healthy, minimally processed, and sensibly priced food products, more attention is being paid to nonthermal food friendly technologies that are environmentally friendly and do not severely affect the product. Cold plasma, ultrasound, high pressure, and pulsed electric field as nonthermal methods have little influence on the most important properties of food and thus have significant potential in this regard, as the food produced by nonthermal methods might be more acceptable to consumers. This paper gives an overview of previously mentioned methods in starch modification. PRACTICAL APPLICATIONS: The food industry, at a recent time, has shown a great interest in the development of procedures which enable minimal food processing and getting products with better organoleptic and nutritive properties with little energy loss and shorter technological procedure duration. This paper presents some of the current research and results of nonthermal methods application in the food industry, mainly its application in starch modification and influence on certain starch properties.

In this study potato and corn starch were subjected to oxidation, using sodium periodate, to obtain dialdehyde starch (DAS) containing different amount of aldehyde groups. The obtained modified starch samples have been characterized with chemical analysis, scanning electron microscopy (SEM) and ATR-FTIR spectroscopy. Then, the samples were exposed to polychromatic UV radiation and the course of photochemical reaction has been monitored with ATR-FTIR spectroscopy. The surface properties of the native and dialdehyde starch before and after UV-irradiation have been determined by contact angle measurements and calculation of surface free energy. The crystallinity of the samples has been estimated with X-ray diffraction (XRD). It has been proved that the dialdehyded corn starch contained a higher amount of functional groups was more photostable than the oxidized potato starch. Sodium iodide(V), firmly bound to DAS macromolecules, has been found to have a significant effect on the photooxidative degradation of the tested systems. In addition, the mechanism of photoinduced reactions in the dialdehyde starch has been proposed.

Starch is the most important storage polysaccharide in higher plants. This polysaccharide is used in many industrial applications as it is abundant, renewable and biodegradable and it can be modified into a wide range of products used in food, animal feed, pharmaceuticals and industry. With the understanding of the starch biosynthesis pathway and the isolation of many of the genes involved in this process, the potential for producing novel starches with improved functionality through genetic modification of plants has become more clear. Several different strategies have been used to achieve the rational design of renewable polymers to meet specific requirements. One of these strategies is the regulation of starch biosynthesis and granule assembly in higher plants. A second strategy involves the expression of heterologous genes encoding biosynthetic or modifying enzymes from other organisms to produce novel products with novel functional properties. In this chapter, these recent developments in starch modification in potato plants, such as alteration of starch composition and production of novel storage polysaccharides, are reviewed.

International audience; 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 β-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.

In recent years, high-pressure treatment (HPT) has become an established process concerning the preservation of food. However, studies dealing with the structural, and consequently functional modification of non-hydrated starchy matrices (moisture content ≤ 15%) by HPT are missing. To close this knowledge gap, pressure (0–600 MPa, 10 min) and pressurization time depending (0–20 min, 450 MPa) alterations of wheat flour were investigated. Pressure rise from 0 to 600 MPa or pressurization time rise from 0 to 20 min resulted in a decline of amylopectin content from 68.3 ± 2.0% to 59.7 ± 1.5% (linearly, R2 = 0.83) and 59.6 ± 0.7% (sigmoidal), respectively. Thereby, detectable total amount of starch decreased from 77.7 ± 0.8% linearly to 67.6 ± 1.7%, and sigmoidal, to 69.4 ± 0.4%, respectively. Increase in pressure caused a linear decrease in gelatinization enthalpy of 33.2 ± 5.6%, and linear increase in hydration properties by 11.0 ± 0.6%. The study revealed structural and technological relevant alterations of starch-based food matrices with low moisture content by HPT, which must be taken into consideration during processing and preservation of food.

Present trends towards technologies and processes that increase the use of residues make starchy vegetal biomass an important alternative material in various applications due to starch’s versatility, low cost and ease of use when its physicochemical properties are altered. Starch is increasingly used in many industrial applications and as a renewable energy resource. Starch can be modified to enhance its positive attributes and eliminate deficiencies in its native characteristics. In this article, the state of knowledge on conventional and unconventional starches and their properties, characteristics, modifications and applications are reviewed.

Plant starches regularly require extensive modification to permit subsequent applications. Such processing is usually done by the use of chemical and/or physical treatments. The use of recombinant enzymes produced by large-scale fermentation of GM microorganisms is increasingly used in starch processing and modification, sometimes as an alternative to chemical or physical treatments. However, as a means to impart the modifications as early as possible in the starch production chain, similar recombinant enzymes may also be expressed in planta in the developing starch storage organ such as in roots, tubers and cereal grains to provide a GM crop as an alternative to the use of enzymes from GM microorganisms. We here discuss these techniques in relation to important structural features and modifications of starches such as: starch phosphorylation, starch hydrolysis, chain transfer/branching and novel concepts of hybrid starch-based polysaccharides. In planta starch bioengineering is generally challenged by yield penalties and inefficient production of the desired product. However, in some situations, GM crops for starch bioengineering without deleterious effects have been achieved.

Objective To investigate the effects of acetylation and pregelatinization of cassava and sweet potato starches on the mechanical and release properties of directly compressed paracetamol tablet formulations in comparison with official corn starch. Methods The native starches were modified by acetylation and pregelatinization. The tablets were assessed using friability (F r ), crushing strength (C s ), disintegration time (D t ) and dissolution parameters. Results Starch acetylation produced paracetamol tablets that were stronger and had the best balance of mechanical and disintegration properties, while pregelatinization produced tablets that were more friable but had a better overall strength in relation to disintegration than formulations made from natural starches. Correlations mainly existed between D t and the dissolution parameters t 80 , t 2 and k 1 in the formulations. Conclusions Modification of the experimental starches improved the mechanical and release properties of directly compressed paracetamol tablet formulations. Thus, they can be developed for use as pharmaceutical excipients in specific formulations.