This study aimed to investigate how the types and order of modifications influence the structure and physicochemical characteristics of modified porous starch. The work focuses on the encapsulation ...of essential oil in hydrophobic microcapsules embedded in sodium alginate hydrogels. FTIR spectra indicated successful esterification of starch with OSA. 1047:1022 cm−1 and 1022:995 cm−1 band ratios of FTIR spectra revealed increased crystallinity due to enzymatic modification, supported by XRD patterns. Porous-OSA (PO) starch had 1.5 times higher degree of substitution (DS) than OSA-porous (OP) starch, confirmed by the intense peak at 0.85 ppm in 1H NMR spectra. SEM images displayed larger particles and smaller pore diameter in OP compared to PO and porous starch, indicating amylolytic enzyme inhibition by OSA. Loading efficiency (LE) showed no significant difference between OP and PO microcapsules (≈70 %), both significantly higher other starch microcapsules. OP and PO microcapsules exhibited sustained release, with enhanced antibacterial activity. Alginate hydrogels preserved about 60 % antioxidant and 90 % antibacterial activities of SEO against 2 h of UV radiation. These findings suggest that the order of modification could not affect the functional properties of final microcapsules. Additionally, the importance of alginate hydrogels as the protective and second wall material was disclosed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Technological advances have led to increased constraints regarding food packaging, mainly due to environmental issues, consumer health concerns, and economic restrictions associated therewith. Hence, ...food scientists and technologists are now more focused on developing biopolymer packages. Starch satisfies all the principal aspects making it a promising raw material for edible coatings/films. Modified starch has grabbed much attention, both at the academic as well as at the industrial level, because these films exhibit dramatic improvement in filming properties without involving any significant increase in cost of production. Various methods, additives used, and recent advances in the field of starch film production are discussed in detail in this review, which also provides an overview of the available information along with recent advances in modified starch film packaging.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Plasticized hydroxypropyl cassava thermoplastic starch (TPS) with glycerol was blended with polybutylene adipate terephthalate (PBAT) via blown-film extrusion. Effects of PBAT/TPS ratios (60/40 and ...50/50) and degrees of substitution (DS) for hydroxypropyl groups in TPS on film properties were investigated. All PBAT/TPS blend films were determined for morphology, thermal stability, thermomechanical, mechanical and barrier properties. Higher DS increased film clarity and glossy surface, improved compatibility between PBAT and TPS, reduced crystallinity and enhanced exposure of hydroxyl groups and hydrogen-bonding of the films. Blending caused phase separation with dispersed starch granules in continuous PBAT matrices, giving high surface roughness. Increased TPS and DS facilitated formation of co-continuous structures and miscibility, improving elongation by approximately 210%. Different DS modified microstructure and hydrophilicity of PBAT/TPS films which consequently reduced water vapor permeability by 34%. Modified DS in hydroxypropyl starch efficiently improved clarity, mechanical and barrier properties of bioplastic packaging.
•Increased degree of hydroxypropylation in TPS improved clarity of PBAT blend films.•Hydroxypropyl group improved miscibility and homogeneous structure of polymer blend.•Film elongation increased by 210% with increasing degree of hydroxypropylation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Complexes formed between heated whey protein isolate (HWPI) and octenyl succinic anhydride (OSA)-modified starches were prepared to stabilize β-carotene-containing oil-in-water emulsions. The ...zeta-potential, turbidity, particle size, and microstructure of the complexes were determined to evaluate the impact of the degree of substitution (DS) of OSA-modified starch on the complexes' structure. HWPI and OSA-modified starches with low DS values formed elongated complexes. With increasing DS, the particle size of the complexes reduced. In comparison to the emulsions stabilized by HWPI or OSA-modified starches, the emulsions stabilized by HWPI/OSAS complexes exhibited superior protection of β-carotene during storage under acidic conditions. When the DS of OSA-modified starch increased, the particle size of emulsions stabilized by the complexes decreased, with less droplet aggregation occurring. The physical stability of these emulsions against storage time, ions, and thermal process showed a positive relationship with the DS, while the β-carotene retention in the emulsions during storage showed a negative relationship with the DS. The greater physical stability of the complex-stabilized emulsions containing OSA-modified starch with a higher DS may be ascribed to enhanced electrostatic repulsion among oil droplets and the formation of a more rigid and denser surface structure in the presence of more OSA groups.
•Complexes between whey protein and octenyl succinic anhydride (OSA)-modified starch were prepared to stabilize emulsions.•Higher degree of substitution (DS) of OSA-modified starch led to smaller particle size of complex-stabilized emulsions.•Higher DS led to greater physical stability of the complex-stabilized emulsions.•Higher DS led to lower β-carotene retention in the complex-stabilized emulsions during storage.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Starch and its derivatives play important roles in food industry. However, the application range of natural starch is limited due to its poor solubility and stability. Enzymatic treatment is one of ...the most commonly used methods to enhance the functions of starch and broaden its application spheres, which is characterized by strong specificity, high efficiency, and mild conditions.
The applications of 4-α-glucanotransferase (4αGT) in the preparation of modified starch and its derivatives were reviewed in this paper, with emphasis on the mechanism of actions of 4αGT, changes of starch structure and properties after 4αGT treatment and the methods to improve the modification effect. Additionally, potential applications of 4αGT-modified starches and its derivatives in the food industry were also discussed and areas that need further researches were pointed out.
4αGT can catalyze disproportionation, coupling, hydrolysis, cyclization reactions. These reactions can be optimized by enhancing the expression level of 4αGT, combining 4αGT with other enzymes or physical and chemical methods, selecting suitable substrates; and optimizing reaction conditions. 4αGT treatments enhanced the properties and functions of starch mainly by changing amylose content, branch chain length distribution and molecular weight distribution. 4αGT modified starch and its derivatives have the potential to be used for encapsulating bioactive agents, creating reduced-calorie foods, sweetener, and prebiotics. Nevertheless, further studies are still needed to develop high-performance and safe 4αGT-modified starches and its derivatives.
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•4αGT catalyze disproportionation, cyclization, coupling, hydrolysis reactions.•The changes mainly focused on side chains, amylose content and molecular weigh.•The digestibility, freeze-thaw stability and gel property were mainly affected.•Further researches are needed to obtain desirable products.•Safety needs to be further explored in order to be widely used in food.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The effects of starches from different botanical sources (waxy corn, cassava, sweet potato, potato, wheat, and corn) and different commercial modified cassava starches (esterified cassava starch, ...cross-linked cassava starch, and oxidized cassava starch) on the physicochemical properties of starch-based films prepared by solution casting method were investigated. The mildew resistance test showed that the cassava starch (CAS) film-forming dispersion had the best mildew resistance and all the modified starch film-forming dispersions had less mildew resistance than that of the native starch film-forming dispersion. The color and transparency of the films depended on the plant sources and modification methods of the starch. Fourier transform infrared (FTIR) analysis verified the formation of hydrogen bonds between the starch and plasticizer (glycerol) and possible sites for hydrogen bonds on the starch. The atomic force microscope (AFM) results showed that the surface of all starch films was homogeneous except waxy corn starch (WCS) film, wheat starch (WS) film, and corn starch (CS) film. Mechanical properties and water vapor permeability (WVP) tests suggested that CAS film had the best comprehensive properties in native starches. For modified cassava starches, the comprehensive properties of the cross-linked CAS film were better than those of other modified CAS films.
•Different starch-based films are fully characterized.•Starches from different plant sources for film formation are studied.•Amylose content has a great effect on the physicochemical properties of the film.•Cross-linked starch film is the most suitable for food preservation.•The results can assist in the matrix selection of starch-based film.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Ultrasound treatment induced microstructural changes on cassava starch granules.•The more drastic ultrasound treatment condition led to total starch gelatinization.•FTIR-ATR and DRX ...results corroborated starch structural disorganization.•Starch ultrasound treatment with ice-bath conditioning enhanced paste stability.•Relationships between microstructural and technological properties were established.
This work was focused on the correlation between the structural and techno-functional properties of ultrasound treated cassava starch for the preparation of tailor-made starch-based ingredients and derivatives. Furthermore, the effect of treatment time, sample conditioning and ultrasound amplitude was studied. Ultrasonic treatment of cassava starch induced structural disorganization and microstructural changes evidenced mainly in the morphological characteristics of the granules and in their degrees of crystallinity. These structural modifications were supported by ATR-FTIR and SEM and CSLM studies as well as DRX and thermal analysis. The selection of the processing conditions is critical due to the complete gelatinization of the starch was produced with the maximum amplitude tested and without temperature control. Rheological dynamical analysis indicated changes at the molecular level in starch granules due to the ultrasound treated, revealing the paste stability under refrigeration condition. PCA allow to establish the interrelationships between microstructural and techno-functional properties. In summary, different starch derivatives could be obtained by adjusting the ultrasound treatment conditions depending on their potential applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Modified starches exhibit high performance as filtrate controller.•The hydrophobic degree of starch influences on filtrate control performance.•The additives present good rheological properties and ...electrical stability.
The influx of the liquid phase of drilling fluid, known as filtrate, in oil and gas producing zones can cause a significant decrease in the relative permeability of the fluids in the reservoir, and consequently, the well’s productivity. The growing interest in developing non-aqueous fluids with low toxicity and good performance under extreme temperature and pressure conditions encourages research in this area. This study investigates the potential of using starch derivatives modified with vinyl esters from fatty acids, as additives to control filtrate in invert-emulsion (W/O) drilling fluids. There are no reports of the use of modified starches as additives to control filtrate in non-aqueous systems. The synthetic drilling fluids used in this study were prepared from a standard formulation, submitted to a dynamic aging process and evaluated by means of physical–chemical filtration tests at high temperature and pressure, along with electrical stability and rheological tests. The results indicate that the formulations developed from fatty esters from starch are able to compete technically with the standard drilling fluid, and the performance of these materials is associated with the degree of chemical modification of the polysaccharide.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Due to the small difference in floatability between dolomite and fluorite, the problems of low grade of fluorite concentrate occur. It is very important to find a depressant that can selectively ...inhibit the floating of dolomite. As a natural polymer, starch is often used as a gangue depressant because of its low price and easy availability. In this paper, the effects of caustic cassava starch (CS) on the single mineral flotation performance of fluorite and dolomite and the flotation separation of mixed ore were studied. Its selective inhibition mechanism was investigated. The results of flotation tests with single minerals stated that the flotation of dolomite was vastly inhibited, while the fluorite was hardly affected when CS was added in flotation using sodium oleate as the collector. The concentrate grade of artificially mixed ore flotation fluorite reached 90.15%, and the recovery rate was 89.54%. The physical adsorption of CS on the surface of dolomite blocked the adsorption of hydrophobic sodium oleate on the surface of dolomite, thus depressing dolomite. The adsorption energy of dolomite and CS was much larger than that of fluorite and CS. This greatly deteriorated the flotation of dolomite and achieved flotation separation between fluorite and dolomite. The results demonstrate that CS is a promising depressant for dolomite in fluorite flotation.
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•The inhibitory effect of CS as a carbonate depressant is studied.•The adsorption modes of CS with dolomite and fluorite are clarified.•The adsorption strength of CS on fluorite and dolomite surface is revealed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Noodle products are widely consumed worldwide. The acceptance and preference of these functional products by consumers can be promoted through the exploration of new knowledge to enhance their ...formulation and quality. Starch and its modified forms are important auxiliary materials or additives for modern food processing. They are considered safe processing auxiliary materials or efficient quality improvers widely used in noodle products. In this review, the physicochemical properties and structural characteristics of native starch and its modified forms used in noodle products are introduced. The applications of native starch, chemically, physically, and enzymatically modified starches in noodle products are reviewed. The application prospects and challenges in starch and its modified forms in noodle products are presented.
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•Study of starch and its common modified forms used in noodle products.•Raw starches do not have functional characteristics needed by manufacturers.•Modified starch can alter significantly starch functional characteristics.•Employment of the modified starch improved noodle quality depending on method type.•Hydroxypropylation and cross-linking can delay/decrease starch retrogradation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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