Plasma modification of starch

Dielectric barrier discharge plasma pre-treatment to facilitate the acetylation process of corn starch under heating/cooling cycles

The objective of the current work was to evaluate the impacts of dielectric barrier discharge plasma and repeated dry-heat treatments on the acetylation process of corn starch. The combined modification resulted in a higher substitution degree of acetate groups on starch chains compared to the acetylation treatment alone. This outcome was linked to the increase in surface area and structural organization level of granules achieved through the application of plasma and heating/cooling cycles, respectively. The successful esterification of starch structure was verified through FTIR (1710 cm-1) and 1H NMR (2 ppm). With the increase in plasma treatment duration up to 20 min, gelatinization enthalpy increased (10.81 J/g) due to the cross-linking reaction. Starch acetate produced through the combined treatment could find the application in the development of low-calorie food formulations due to its high resistant starch (70.5 g/100 g) and low viscosity (43 mPa s).

The effect of cold plasma on starch: Structure and performance

The inherent side effects of the physico-chemical properties of native starches often severely limit their use in food and non-food industries. Plasma is a non-thermal technology that allows rapid improvement of functional properties. This review provides a comprehensive summary of the sources and mechanisms of action of cold plasma and assesses its effects on starch morphology, crystal structure, molecular chain structure and physicochemical properties. The complex relationship between structure and function of plasma-treated starch is also explored. Potential applications of plasma-modified starch are also discussed in detail. The outcome of the modification process is influenced by factors such as starch type and concentration, plasma source, intensity and duration. The properties of starch can be effectively optimised using plasma technology. Plasma-based technologies therefore have the potential to modify starch to create a range of functionalities to meet the growing market demand for clean label ingredients.

Effect of dielectric barrier discharge (DBD) plasma treatment on physicochemical and 3D printing properties of wheat starch

In recent years, the focus has shifted towards carbohydrate-based hydrogels and their eco-friendly preparation methods. This study involved an investigation into the treatment of wheat starch using dielectric barrier discharge (DBD) plasma technology over varying time gradients (0, 2, 5, 10, 15, and 20 min). The objective was to systematically examine the impact of different treatment durations on the physicochemical properties of wheat starch and the suitability of its gels for 3D printing. Morphology of wheat starch remained intact after DBD treatment. However, it led to a reduction in the amylose content, molecular weight, and crystallinity. This subsequently resulted in a decrease in the pasting temperature and viscosity. Moreover, the gels of the DBD-treated starch exhibited superior 3D printing performance. After a 2-min DBD treatment, the 3D printed samples of the wheat starch gel showed no significant improvements, as broken bars were evident on the surface of the 3D printed graphic, whereas DBD-20 showed better printing accuracy and surface structure, compared to the original starch without slumping. These results suggested that DBD technology holds potential for developing new starch-based gels with impressive 3D printing properties.

Effect of atmospheric pressure plasma jet on the structure and physicochemical properties of wheat starch

The effect of atmospheric pressure plasma jet (APPJ) with different discharge power (0, 400, 600, and 800 W) on the structure and physicochemical properties of wheat starch were evaluated in this study. After APPJ treatments, significant declines in peak viscosity, breakdown viscosity, and final viscosity of wheat starch pasting parameters were observed with increase of plasma treatment power. Being treated with discharge power of 800 W, the PV and BD value of wheat starch paste significantly dropped to 2,578 and 331 cP, respectively. Apparently, APPJ could raise the solubility of wheat starch, while reduce the swelling capacity, and also lower the G' and G″ value of wheat starch gel. Roughness and apparent scratch was observed on the surface of the treated wheat starch granules. Although APPJ treatment did not alter wheat starch's crystallization type, it abated the relative crystallinity. APPJ treatment might be useful in producing modified wheat starch with lower viscosity and higher solubility.

Understanding the atmospheric cold plasma-induced modification of finger millet (Eleusine coracana) starch and its related mechanisms

This research was conducted to evaluate the effects of cold plasma (CP) on finger millet starch (FMS). FMS was exposed to partially ionized gas at varying voltages (170, 200, and 230 Volt) for varied time (10, 20, and 30 mins). The impact of treatment was studied using physico-chemical, and functional properties, and the mechanisms of starch modification occurring were stated. A significant reduction in the degree of polymerization was noticed based on parameters like reducing sugar, amylose content, solubility, and molecular weight. However, in certain voltage and time combinations, crosslinking was also confirmed by analysis such as XRD, FTIR, DSC, etc. The properties of starch were altered such as remarkable increase in water solubility by 6.7 times for highest voltage and longest time (230 V/30 min) was registered. NMR data suggested valuable findings- oxidation of OH group at C6 position of starch led to formation of carbonyl group followed by carboxyl group. NMR also showed a decrease in OH protons confirming crosslinking and hence all these analyses helped to conclude findings about the quality changes using CP. It was observed that the highest voltage and considerably longer exposure time of 20 and 30 min induced significant changes in the FMS.

Effects of cold plasma pretreatment combined with sodium periodate on property enhancement of dialdehyde starch prepared using native maize starch

This study represents the inaugural investigation into the effect of cold plasma (CP) pretreatment combined with sodium periodate on the preparation of dialdehyde starch (DAS) from native maize starch and its consequent effects on the properties of DAS. The findings indicate that the maize starch underwent etching by the plasma, leading to an increase in the particle size of the starch, which in turn weakened the rigid structure of the starch and reduced its crystallinity. Concurrently, the plasma treatment induced cleavage of the starch molecular chain, resulting in a decrease in the viscosity of the starch and an enhancement of its fluidity. These alterations facilitated an increased contact area between the starch and the oxidising agent sodium periodate, thereby augmenting the efficiency of the DAS preparation reaction. Consequently, the aldehyde group content was elevated by 9.98 % compared to the conventional DAS preparation methodology. Therefore, CP could be an efficient and environmentally friendly non-thermal processing method to assist starch oxidation for DAS preparation and property enhancement.

Dielectric barrier discharge cold plasma modifies the multiscale structure and functional properties of banana starch

Banana starch has attracted significant attention due to its abundant content of resistant starch. This study aims to compare the multiscale structure and functional properties of banana starch obtained from five cultivated varieties and investigate the impact of dielectric barrier discharge cold plasma (DBD) treatment on these starch characteristics. All five types of natural banana starch exhibited an elliptical and irregular shape, conforming to the CB crystal structure, with a bimodal distribution of branch chain lengths. The resistant starch content ranged from 88.9 % to 94.1 %. Variations in the amylose content, amylopectin branch chain length distribution, and structural characteristics resulted in differences in properties such as gelatinization behavior and sensitivity to DBD treatment. The DBD treatment inflicted surface damage on starch granules, reduced the amylose content, shortened the amylopectin branch chain length, and changed the relative crystallinity to varying degrees. The DBD treatment significantly increased starch solubility and light transmittance. Simultaneously, it resulted in a noteworthy decrease in peak viscosity and gelatinization enthalpy of starch paste. The in vitro digestibility test showed that 76.2 %-86.5 % of resistant starch was retained after DBD treatment. The DBD treatment renders banana starch with reduced viscosity, increased paste transparency, enhanced solubility, and broadens its potential application.

Effect of free radicals on rheological properties, antioxidant activity, and molecular conformation of chitosan under solution pulsed plasma process based on radical scavengers

Radical scavengers were employed to evaluate the influence of various active species (•OH, •O, and H2O2) on the rheological properties, antioxidant activity, and molecular conformation of chitosan under solution plasma process (SPP) degradation. ESR analysis showed that •OH and •O radicals played important roles in SPP degradation. The results of rheological properties and antioxidant activity indicated that the •OH scavenger (tert-butanol), •O scavenger (1, 4-benzoquinone), and H2O2 scavenger (MnO2) remarkably inhibited the decrease of G' and G" of the degraded chitosan, the formation of gel structure, and the increase of antioxidant activity. The analysis of molecular conformation of the chitosan by particle size analysis, atomic force microscopy (AFM), and high performance size exclusion chromatography coupled with multi-angle laser light scattering (HPSEC-MALLS) revealed that the decrease of particle size, molecular aggregation, and molecular weight of chitosan was inhibited after the addition of radical scavengers. An evident effect of radical scavengers on the hard sphere conformation of chitosan was observed. It was found that the above effects were strongly dependent on the scavenger concentration. These results proved that •OH, •O, and H2O2 played important roles in SPP treatment. For the rheological properties and molecular conformation, H2O2 exhibited the greatest impact. For the antioxidant activity and molecular weight, •OH presented the biggest influence. Besides, •O expressed the weakest effect. This study will be beneficial to reveal the action mechanisms of SPP technology to the degradation of chitosan.

Development and Characterization of Edible Films Based on Cassava Starch Modified by Corona Treatment

Corona treatment (CT), a surface treatment widely used in the plastic industry, can be used to alter the properties of cassava starch. In the present work, CT was performed on dry granular starch (DS), water-suspended humid granular starch (HS), and gelatinized starch (GS). Different properties and structural characteristics of treated starches were studied. A lowering in pH was generally observed after CT and the rheological properties depended on the starch presentation. A reinforcement of DS and HS samples after CT was deduced from higher viscosity values in flow assays and viscoelastic moduli, but weak gels were obtained when CT was applied to GS. Changes in the A-type polymorphic structure, as well as a drop in relative crystallinity, were produced by CT for DS and HS. Additionally, changes in O-H and C-O-C FTIR bands were observed. Therefore, CT can be applied for starch modification, producing predominantly cross-linking in the DS and de-polymerization in the HS. Casting films made from the modified DS showed higher tensile strength and lower hydrophilicity, solubility, water absorption capacity, and water vapor permeability. Thus, the DS cross-linking induced by CT improved mechanical characteristics and hydrophobicity in edible films, which can be better used as packaging materials.

Effect of high voltage dielectric barrier discharge (DBD) atmospheric cold plasma treatment on physicochemical and functional properties of taro (Colocasia esculenta) starch

The goal of the proposed study is to investigate the effects of three different power levels (30, 32 and 34 kV) and exposure time (2, 4 and 8 min) of dielectric barrier discharge (DBD) atmospheric cold plasma treatment on the functional and physicochemical characteristics of taro starch. Investigations were done into how different treatments impact the multi-structural, functional and physicochemical attributes of taro starch. The findings showed that cold plasma treatments substantially impacted starch granule shapes (3.60-2.54 μm), such as reduced aggregations and developed fissures on granule surface due to the generation of an etching by plasma species and enhancement in the surface topography and roughness of treated starch as compared with native by SEM and AFM analysis. Besides this, no variations were detected in the functional groups of taro starch using FT-IR analysis after cold plasma treatments. However, the A-type pattern in the XRD did not affect it, while a reduction in relative crystallinity (14.20-11.50 %) was seen as a function of the active plasma species depolymerization. Furthermore, depending on the cold plasma voltage and treatment time, amylose content (20.12-15.98 %), paste clarity (24.48-31.27 %), solubility (0.41-65.53 %), freezing thaw stability (% syneresis) (32.10-42.58 %), color properties (L*, 94.79-97.52), whiteness index (79.37-84.66), molecular weight distribution (Peak 1, 12.79-5.35 × 108 g/mol; Peak 2, 4.20-1.56 × 107 g/mol) and in vitro digestibility (RDS, 64.10-64.08 %) significantly changed. So, based on these excellent properties, this study suggested that cold plasm-treated taro starch can be used in the field of food packaging material, functional food and pharmaceutical products. Therefore, a potential approach for physically altering starch is plasma treatment.

Understanding CaCl2 induces surface gelatinization to promote cold plasma modified maize starch: Structure-effect relations

To investigate the influence of surface gelatinization on cold plasma (CP) modification of starch, this study used CaCl2 to modify maize starch by surface gelatinization, further combined with CP treatment and characterized its multi-scale structure and physicochemical properties. The results revealed that starch surface gelatinization causes roughness and fragmentation on the granule surface, and CP undergoes etching effects. The synergistic modification promotes starch degradation, as evidenced by molecular weight decrease and short-chain ratio increase. Although the growth rings, FT-IR patterns, and crystal types of starch remained unchanged, the synergistic modification induced a reduction in the short-range orderliness and crystallinity of starch, thus causing a decrease in the pasting properties and contributing to its solubility. Notably, the CP treatment improved the RDS and SDS contents of the gelatinized starch due to more active sites on the granule surface after gelatinization, and this finding may provide insight into the deep processing of starch.

Plasma Effects on Properties and Structure of Corn Starch: Characterization and Analysis

This research investigated the impact of air plasma and high-pressure plasma treatments on corn starch. The resulting samples were characterized by particle morphology, molecular polymerization degree, molecular functional groups, and crystallinity. SEM analysis revealed that plasma treatment altered the surface morphology of corn starch, with variations observed depending on the duration of treatment. UV/Vis spectroscopy results indicated that longer plasma exposure times increased maximum absorbance values with less complete peak shapes. FTIR results demonstrated that plasma treatment disrupted the crystalline structure of starch, resulting in decreased molecular polymerization. Lastly, XRD results showed a proportional relationship between plasma treatment duration and the intensity of the diffuse peak, indicating that prolonged plasma exposure increased the amorphous nature of starch.

Enhanced properties of non-starch polysaccharide and protein hydrocolloids through plasma treatment: A review

Hydrocolloids are important ingredients in food formulations and their modification can lead to novel ingredients with unique functionalities beyond their nutritional value. Cold plasma is a promising technology for the modification of food biopolymers due to its non-toxic and eco-friendly nature. This review discusses the recent published studies on the effects of cold plasma treatment on non-starch hydrocolloids and their derivatives. It covers the common phenomena that occur during plasma treatment, including ionization, etching effect, surface modification, and ashing effect, and how they contribute to various changes in food biopolymers. The effects of plasma treatment on important properties such as color, crystallinity, chemical structure, rheological behavior, and thermal properties of non-starch hydrocolloids and their derivatives are also discussed. In addition, this review highlights the potential of cold plasma treatment to enhance the functionality of food biopolymers and improve the quality of food products. The mechanisms underlying the effects of plasma treatment on food biopolymers, which can be useful for future research in this area, are also discussed. Overall, this review paper presents a comprehensive overview of the current knowledge in the field of cold plasma treatment of non-starch hydrocolloids and their derivatives and highlights the areas that require further investigation.

Customizing Starch Properties: A Review of Starch Modifications and Their Applications

Starch has been a convenient, economically important polymer with substantial applications in the food and processing industry. However, native starches present restricted applications, which hinder their industrial usage. Therefore, modification of starch is carried out to augment the positive characteristics and eliminate the limitations of the native starches. Modifications of starch can result in generating novel polymers with numerous functional and value-added properties that suit the needs of the industry. Here, we summarize the possible starch modifications in planta and outside the plant system (physical, chemical, and enzymatic) and their corresponding applications. In addition, this review will highlight the implications of each starch property adjustment.

Hierarchical structural modification of starch via non-thermal plasma: A state-of-the-art review

The hierarchical architecture of natural and processed starches with different surface and internal structures determines their final physicochemical properties. However, the oriented control of starch structure presents a significant challenge, and non-thermal plasma (cold plasma, CP) has gradually been used to design and tailor starch macromolecules, though without clear illustration. In this review, the multi-scale structure (i.e., chain-length distribution, crystal structure, lamellar structure, and particle surface) of starch is summarized by CP treatment. The plasma type, mode, medium gas and mechanism are also illustrated, as well as their sustainable food applications, such as in food taste, safety, and packaging. The effects of CP on the chain-length distribution, lamellar structure, amorphous zone, and particle surface/core of starch includes irregularity due to the complex of CP types, action modes, and reactive conditions. CP-induced chain breaks lead to short-chain distributions in starch, but this rule is no longer useful when CP is combined with other physical treatments. The degree but not type of starch crystals is indirectly influenced by CP through attacking the amorphous region. Furthermore, the CP-induced surface corrosion and channel disintegration of starch cause changes in functional properties for starch-related applications.

Effects of pin-to-plate atmospheric cold plasma for modification of pearl millet (Pennisetum glaucum) starch

The present study was done to analyze the effect of atmospheric pressure non-thermal pin-to-plate plasma at a range of different voltages (170, 200, and 230V) at different time intervals (10, 20, and 30 mins) on under-utilized pearl millet starch. The untreated and treated starches were analyzed for amylose content, pH, carbonyl, and carboxyl group, reducing sugar, turbidity, water, and oil binding property, pasting property, DSC, FTIR, XRD, and molecular weight. As cold plasma contains highly reactive species and free radicals, it is expected to cause noticeable modifications in the attributes of treated starch. There has been a significant reduction (p < 0.05) in turbidity value by 38.97% and pH value of starch from 6.49 to 4.05. Plasma-treated samples produced clearer pastes with higher stability over storage time. Cold plasma treatment also led to an increase in the ζ potential. However, there has been no significant change in the water activity and oil-binding capacity of the starch. Reducing sugar content, average molecular weight, degree of polymerization, pasting property, XRD, and FTIR data confirmed that cross-linking takes place in samples treated at lower voltages and lesser time followed by depolymerization occurring in harshly treated plasma samples. The study thus points out the possible use of cold plasma for starch modification to produce starches with altered properties.

Product development and X-Ray microtomography of a traditional white pan bread from plasma functionalized flour

Cold plasma (CP) technology has emerged as a novel non-thermal technology with the potential to improve food quality or impart functionality to ingredients. Our previous studies on wheat flour demonstrated how the structure and functionality of wheat flour might be modified using CP to provide an alternative to chemical additives (Chaple et al., 2020). However, understanding of the further effects of plasma functionalized ingredients in existing or new product formulation is limited. This study investigated the effects of CP treatment of wheat flour on traditional white pan bread development. The bread was formulated using plasma functionalized flour (PFF), and critical product characteristic responses were analyzed. Plasma treatment of flour positively affected the bread's expansion ratio, crust color, and water activity. Farinograph analysis suggests improvement in water absorption capacity, dough development time, and dough stability. X-Ray Microtomography (XRMT) analysis was conducted to understand how plasma functionalising the flour impacted the microstructure of bread. The 3D scans suggested no macro-change in the bread matrix compared to control; however, the porosity decreased in line with the increasing plasma treatment duration of the flour. The texture profile analysis showed an improvement in the gluten network developed in the dough developed from PFF. Sensory analysis results showed overall acceptance for bread formulated with PFF compared with a commercial sample. Overall, CP treatment of the flour improved the functionality in relation to dough and bread preparation and can thus provide an alternative to chemical additives in bread making. The CP processes may be modulated to deliver tailored effects for bread product development.

Porous corn starch obtained from combined cold plasma and enzymatic hydrolysis: Microstructure and physicochemical properties

The combined effect of cold plasma treatment and enzymatic hydrolysis was investigated on the physicochemical and microstructural properties of porous corn starch. Scanning electron microscopy (SEM) images depicted that the combined treatment led to the creation of deeper pores on the surface of starch granules. The combined treatment indicated the highest swelling power (19.49 g/g), solubility (10.08 %), specific surface area (2.97 m²/g) and total pore volume (10.47 cm³/g). According to the X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC), the combined treatment, compared with the enzymatic hydrolysis, decreased the starch crystallinity, the order of the double-helix structure, and the starch gelatinization enthalpy. The rapid visco analyzer (RVA) pasting profile revealed that the combined treatment elevated the breakdown and setback viscosities. This study indicated that cold plasma pretreatment, as a green non-thermal technology, facilitated the performance of enzymes, resulting in the production of a porous starch with a higher absorption capacity.

Designing food for the elderly: the critical impact of food structure

Ageing is an unavoidable progressive process causing many changes of the individual life. However, if faced in an efficient way, living longer in a healthy status could be an opportunity for all. In this context, food consumption and dietary patterns are pivotal factors in promoting active and healthy ageing. The development of food products tailored for the specific needs of the elderly might favour the fulfilment of nutritionally balanced diets, while reducing the consequences of malnutrition. To this aim, the application of a food structure design approach could be particularly profitable, being food structure responsible to the final functionalities of food products. In this narrative review, the physiological changes associated to food consumption occurring during ageing were firstly discussed. Then, the focus shifted to the possible role of food structure in delivering target functionalities, considering food acceptability, digestion of the nutrients, bioactive molecules and probiotic bacteria.

Dielectric barrier discharge cold plasma combined with cross-linking: An innovative way to modify the multi-scale structure and physicochemical properties of corn starch

Cold plasma is a low-cost, simple and green method for starch modification. In the present study, the impact of corn starch modification by cold plasma (CP, 1, 3 and 9 min), sodium trimetaphosphate/sodium tripolyphosphate (CL, 1 %, 5 % and 10 %) and their combination were investigated. CP-pretreatment had enhancement of phosphorus content and substitution degree. Neither CP nor CL destroyed the starch granules morphology. Instead, CP induced more short-chain to better rearrange the starch during the crosslinking process, which improved the efficiency of the crosslinker in the subsequent crosslinking process. Therefore, compared with CL or CP, the thermal transition temperatures increased after CP pretreatment, while the amylose content, relative crystallinity, swelling power, and △H decreased. Meanwhile, CP-pretreatment changed the internal structure of the CL-starch so that it showed the lowest enzymatic digestibility. CP pretreatment provides a promising way to improve cross-linked starch's structure, properties, and efficiency.

Rheological Properties of Wheat Flour Modified by Plasma-Activated Water and Heat Moisture Treatment and in vitro Digestibility of Steamed Bread

The study investigated the effects of plasma-activated water (PAW) and heat moisture treatment (HMT) on the rheological properties of wheat flour and the in vitro digestibility of steamed bread partially replaced by the modified wheat flour. After HMT, the gelatinization temperature of wheat flour increased and the gelatinization enthalpy reduced. The solubility and swelling power of wheat flour increased after the heat-moisture treatment. The solubility of modified flour after PAW-HMT treatment was lower than that of distilled water (DW)-HMT at the same temperature. The wheat flour with HMT had higher storage modulus (G') and loss modulus (G“), and had better ductility and deformability. Common wheat flour was partially replaced by modified flour to make steamed bread. The results indicated that the volume, height, diameter and specific volume of steamed bread were significantly decreased with the addition of HMT flour. However, the hardness, viscosity and chewiness increased significantly. The resistant starch content of steamed bread with the modified wheat flour increased. The results provide new insights for the development of new functional steamed bread.

Preparing potato starch nanocrystals assisted by dielectric barrier discharge plasma and its multiscale structure, physicochemical and rheological properties

Non-thermal plasma has increasingly been used for surface modification of various materials as a novel green technology. In this study, we prepared potato starch nanocrystals (SNCs) assisted by dielectric barrier discharge plasma technology and investigated its multiscale structure, physicochemical properties and rheology. Plasma treatment did not change the morphology and crystalline pattern of SNCs but reduced the crystallinity. The amylose content, swelling power, gelatinization temperature, and apparent viscosity of SNCs decreased after the plasma process by depolymerizing the amylopectin branch chains and degrading SNCs molecules. Besides, plasma increased the rapidly digestible starch and resistant starch content. Changes in rheological properties of plasma treated SNCs suggested that the plasma process increased the flowing capacity. The effective structural and functional changes of plasma treated SNCs confirm that plasma technology has great potential for modification of SNCs.

Dielectric barrier discharge plasma: A green method to change structure of potato starch and improve physicochemical properties of potato starch films

The effects of dielectric barrier discharge (DBD) plasma treatment on the physicochemical properties of potato starch and its films were studied. The results showed that the plasma species caused etching lead to small cracks and pores in potato starch particles and that oxidation, de-polymerization, and crosslinking were the main mechanisms underlying the effects of DBD plasma treatment. As the treatment time extended, starch hydrolysis, turbidity, syneresis, and gelatinization temperatures increased first and then decreased, whereas the solubility, swelling power, and water absorption significantly increased (P < 0.05). There was a decrease in the retrogradation tendency of the starch gels. The surfaces of the DBD plasma-modified potato starch-based films were relatively flat. After a 9-min treatment, the films exhibited the lowest water vapor permeability and highest tensile strength. In conclusion, the use of DBD plasma is a simple and green method to enhance the properties of potato starch and its film.

Cold plasma technologies: Their effect on starch properties and industrial scale-up for starchmodification

Native starches have limited applications in the food industry due to their unreactive and insoluble nature. Cold plasma technology, including plasma-activated water (PAW), has been explored to modify starches to enhance their functional, thermal, molecular, morphological, and physicochemical properties. Atmospheric cold plasma and low-pressure plasma systems have been used to alter starches and have proven successful. This review provides an in-depth analysis of the different cold plasma setups employed for starch modifications. The effect of cold plasma technology application on starch characteristics is summarized. We also discussed the potential of plasma-activated water as a novel alternative for starch modification. This review provides information needed for the industrial scale-up of cold plasma technologies as an eco-friendly method of starch modification.

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Cold plasma technology could be an effective, sustainable alternative for starch modification.

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The extent of modification of starches from different botanical sources depends on the type of cold plasma technology used.

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For mainstream adoption of cold plasma modified starches, research on safety and consumer perception must be conducted.

Effect of atmospheric pressure non-thermal pin to plate plasma on the functional, rheological, thermal, and morphological properties of mango seed kernel starch

This study aimed to investigate the effect of atmospheric pressure non-thermal pin-to-plate plasma on the functional, rheological, thermal, and morphological properties of mango seed kernel starch. As cold plasma contains highly reactive species and free radicals, it is expected to cause noticeable modifications in the attributes of starch treated. The isolated mango seed kernel starch was subjected to the plasma treatment of input voltages 170 and 230 V for 15 and 30 min of exposure. Water adsorption, swelling, and solubility at lower temperatures. There has been a significant reduction (p < 0.05) in pH values of starch from 7.09 to 6.16 and also the desirable reduction in turbidity values by 42.60%. However, there has been no significant change in the oil and water binding behavior of the starch. The FTIR spectra of MSKS demonstrate the formation of amines which contributes to the better hydrophilic nature of the starch. The structural modification has been adequately confirmed by SEM images. The maximum voltage and time combination, lead to depolymerization of starch which is supported by NMR spectra thus affecting thermal and rheological properties. The application of cold plasma-modified MSKS in food would facilitate stable and smooth textural development.

Nonthermal physical modification of starch: An overview of recent research into structure and property alterations

To tailor the properties and enhance the applicability of starch, various ways of starch modification have been practiced. Among them, physical modification methods (micronization, nonthermal plasma, high-pressure, ultrasonication, pulsed electric field, and γ-irradiation) are highly potential for starch modification considering its safety, environmentally friendliness, and cost-effectiveness, without generating chemical wastes. Thus, this article provides an overview of the recent advances in nonthermal physical modification of starch and summarizes the resulting changes in the multi-level structures and physicochemical properties. While the effect of these techniques highly depends on starch type and treatment condition, they generally lead to the destruction of starch granules, the degradation of molecules, decreases in crystallinity, gelatinization temperatures, and viscosity, increases in solubility and swelling power, and an increase or decrease in digestibility, to different extents. The advantages and shortcomings of these techniques in starch processing are compared, and the knowledge gap in this area is commented on.

Temperature of plasma-activated water and its effect on the thermal and chemical surface properties of cereal and tuber starches

High amylose and waxy starches from maize and potato were incubated with plasma-activated water (PAW) at 25 °C, 60 °C, and 80 °C temperatures to investigate PAW treatment effects on the starches' properties. At 60 °C incubation temperature, the starches were basically annealed with PAW. Annealing starches with PAW significantly increased (p < 0.05) the gelatinization parameters except for the enthalpy of gelatinization of waxy potato starch. Furthermore, starch swelling power significantly decreased while the water absorption capacity and solubility increased significantly when incubated at 80 °C. X-ray photoelectron spectroscopy (XPS) analysis showed the oxidation of C–C/C–H and C–O into carboxyl groups in waxy and high amylose maize starches incubated with PAW at 60 °C and 80 °C, respectively. In addition, cross-linking was observed in waxy maize and high amylose potato incubated with PAW at 80 °C and 25 °C, respectively. Overall, the results indicated PAW temperature is an important factor in modifying cereals and tuber starches with PAW.

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Maize and potato starches were treated with plasma-activated water (PAW).

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Increasing the temperature of PAW improves the hydration properties of starch.

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Gelatinization temperatures increased with an increase in the temperature of PAW.

The multi-scale structure and physicochemical properties of mung bean starch modified by ultrasound combined with plasma treatment

Plasma is a simple, effective and promising food processing technology with great potential for starch modification. Mung bean starch was subjected to ultrasound (300 W, 10, 30 and 50 min), plasma (40 V, 1, 3 and 9 min) and the synergistic treatment, as well as investigating its effects on the morphology, chain length distribution, molecular weight, crystalline structure and physicochemical properties of starch. Ultrasound and plasma treatment did not change the granule shape, but caused some corrosions on the surface, and dual treatment increased the damage degree of starch granules surface. All treatments decreased the molecular weight (Mw), amylopectin long chains and crystallinity but increased the gelatinization temperatures and enthalpy. Different from ultrasound irradiation, single plasma treatment significantly reduced the swelling power and pasting viscosities. Furthermore, dual treatment increased the thermal stability of starch paste, owing to the reinforcement effect between ultrasound and plasma. Thus, dual modification displayed an excellent ability to modify starch with specific characteristics and expand the potential application of mung bean starch in the food industry.

Modification of cellulose from sugarcane (Saccharum officinarum) bagasse pulp by cold plasma: Dissolution, structure and surface chemistry analysis

Cellulose is a most abundant natural biopolymer, however, the strong hydrogen bonding system makes cellulose hard to dissolve, limiting its further applications. In this study, an innovative cold plasma (CP) technology was used to modify cellulose from sugarcane (Saccharum officinarum) bagasse pulp. Dissolution, structure, and surface chemistry of cellulose before and after CP treatment were investigated. Results showed that the dissolution rate of cellulose after different CP treatment time (3-12 min) and operating voltage (40-70 kV) was significantly improved. Roughness, even holes (CP treatment 9 min with 50 kV) and breakage (CP treatment 9 min with 70 kV) were observed on the surface. The crystallinity index decreased from 62.31% (control) to 60.88% (CP treatment 3 min with 50 kV). The hydrogen bonding force was weakened and the peak intensity of CO and CO stretching vibration groups were enhanced. Therefore, CP-modified cellulose may be applied more in future, such as biological films for food future packaging.

Cold Plasma Processing on Fruits and Fruit Juices: A Review on the Effects of Plasma on Nutritional Quality

This review aims to present the effects of cold plasma technology on the nutritional quality of fruits and fruit juices. This review focuses on the chemical changes induced by plasma on several bioactive compounds, such as sugars, starch, lipids, vitamins, phenolic compounds, carotenoids, and anthocyanins. The main plasma-reacting species that reacts with fruit compounds are presented and discussed. The review presents the mechanisms that lead to the improvement and degradation of the main compounds, showing both the advantages and disadvantages of cold plasma technology.