SDS Content Research Articles

Regulating heat-induced fibrous whey protein-wheat starch composite emulsion gels as dysphagia food by preheating temperature: Insights from protein-starch interactions

Heat-induced processes significantly affect the gel behavior of protein and starch, but the mechanism by which preheating temperature affects the quality characteristics of the gel is unclear. Herein, to explore the feasibility of developing texture-modified foods based on proteins, carbohydrates and lipids, the effects of preheating temperatures (40–80 °C) on the texture and starch digestibility of fibrous whey protein (FWP)-wheat starch composite emulsion gels (CEGs) under two-step heating condition were investigated. The rheological and texture properties, protein-starch interactions and microstructure of CEGs were characterized. The results showed that preheating temperature synchronously regulated the texture and starch digestibility of heat-induced CEGs. When preheating temperature is below 60 °C, two-step heated CEGs showed bicontinuous networks with harder texture, similar as one-step heated gels. While temperature exceeds 60 °C, preheating altered FWP conformation and promoted protein-starch interactions, forming protein-starch complexes or protein aggregates. This changed protein distribution and disrupted bicontinuous network, forming more hydrophobic interaction, yielding a soft-textured CEGs. In this case, SDS content increased and RS content decreased. Notably, two-step heating process with high preheating temperature (>60 °C) is universal for softening fibrous whey protein-starch-based composite gels. This study enhances the understanding of traditional heat-induced protein-starch gelation processes and provides a simple and feasible method for developing texture-modified foods.

Effects of synergistic action on rheological and thermal properties of potato starch complexes co-gelatinized with caffeic acid and squash polysaccharides extracted with water and subcritical water

In order to broaden the application range of squash polysaccharide (WESP/SWESP) and caffeic acid (CAA) and improve the quality of potato starch (PS) products, the effects of WESP/SWESP and CAA on the gelatinization, rheology, thermodynamics, microstructure and in vitro digestion of PS were investigated. Meanwhile, the synergistic effect of WESP/SWESP and CAA on PS was further analyzed. Differently, due to WESP and SWESP had different monosaccharide composition and structure, they had different effects on the system. Pasting properties results showed that the presence of WESP/SWESP and CAA significantly reduced the peak viscosity, trough viscosity, breakdown viscosity and final viscosity of PS, especially under the combined action. In rheological tests, all sample gels belonged to the pseudoplastic fluids and weak gel system (tan δ < 1). Besides, thermodynamic properties revealed that WESP/SWESP and CAA synergistic effect had better retrogradation delay effect. In the ternary system, WESP/SWESP, CAA and PS can form a new network structure and improve the stability of the gel system. In addition, the results of infrared spectroscopy, Raman spectroscopy, x-ray diffraction and scanning electron microscopy exhibited that the ternary system can promote the accumulation and winding of the spiral structure of PS chain, and make the structure of PS gel network more orderly and stable. Furthermore, compared with PS gel, the ternary system had lower RDS and higher SDS and RS content, suggesting that the addition of WESP/SWESP and CAA at the same time was more conducive to reducing the hydrolysis rate of PS. This work revealed the interaction between WESP/SWESP, CAA and PS, which improved the physicochemical and digestive properties of PS. It will provide a theoretical basis for improving the quality of potato starch-related products and developing functional foods.

Characteristics of rice starches modified by single and dual heat moisture and osmotic pressure treatments

The effect of osmotic pressure treatment (OPT), heat moisture treatment (HMT), and their dual combination as HMT-OPT and OPT-HMT on functional and pasting properties, gel texture, crystallinity, thermal, morphological, and rheological properties, and in vitro digestibility of modified starches were investigated. HMT was done with 29 % moisture at 111 °C for 45 min while OPT was performed at 117 °C for 35 min with saturated sodium sulphate solution. All modifications increased amylose content, improved pasting stability, and reduced swelling power and solubility. Dual modifications caused higher morphological changes than single modified starches. HMT and OPT increased pasting temperature, setback and final viscosity while decreased peak viscosity and breakdown, whereas HMT-OPT and OPT-HMT reduced all pasting parameters except pasting temperature. 1047/1022 and 995/1022 ratios and relative crystallinity decreased. V-type polymorphs were formed, and gelatinization temperature range increased with lower gelatinization enthalpy. Starch gel elasticity, RS and SDS content were enhanced to a greater extent after HMT-OPT and OPT-HMT. HMT as a single and dual form with OPT showed prominent effect on pasting, thermal, crystalline, and rheological properties. Application of HMT, OPT and dual modified starches with improved functionalities may be targeted for suitable food applications such as noodles.

Identifying factors that inhibit or facilitate on-site implementation of chemical risk assessment at small and medium-sized companies.

The introduction and implementation of chemical risk assessment is difficult, especially at small and medium-sized manufacturing and construction companies. This study aimed to identify the factors that inhibit or facilitate such assessment. Twelve individuals in charge of risk assessment at one medium-sized client company and eight small and medium-sized contract companies and responsible for innovation in the manufacturing and construction industries were interviewed. The interview transcripts were analyzed via text mining using KH Corder ver. 3 and a co-occurrence network was used to identify the keywords' connections and each factor in consideration of the interviews. Six factors inhibited or facilitated risk assessment: (1) education on hazardous work in the workplace, (2) improvement suggestions and reduction measures from client and staff, (3) cooperation between employees and contractors in the workplace, (4) thoroughly explanation of SDS content for better understanding, (5) risk awareness based on accident examples, and (6) difficulties imagining the hazards of chemical substances. Factors (1), (2), (3), and (5) were positive, facilitating factors; (4) and (6) were negative, inhibiting factors. This study highlights that it is necessary to educate workers about chemical substance risks using safety data sheets and accident examples in chemical risk assessment.

The feasibility of utilizing sifted desert sand (

To deal with the shortage of the raw materials, like cement, gravel, and sand in the construction and building materials (CBM) industry, the feasibility of utilizing the desert sand (DS) was investigated. In this research, the DS sourced from Maowusu desert was applied. As inspired by that the smaller the particles, the more reactive of the powder, the particles smaller than 75 μm (which is called sifted desert sand, SDS) was sieved with its physical properties and chemical compositions being evaluated and compared with the original DS. It showed that compared with DS powder, the SDS particles have much smaller size (median diameter = 52 μm) and smoother surfaces, with lower SiO2 content, and much higher contents of alkaline oxide, Al2O3 and CaO in particular, which indicated a higher activity of the SDS. Then, the SDS was used to partly replace the cement clinker with varying dosages to prepare the paste samples. The results indicated that the compressive strength of the pastes at 3 days, 7 days, and 28 days all follow an order of increasing firstly, then decreasing gradually, with increasing SDS content. Then, analytical calculation was applied to determine the strength of the SDS-cement paste and the values were compared with the experimentally measured values to probe into the role SDS played. Via combination with microstructure examination, it showed that when SDS was introduced, except for the dilution effect and nucleation effect, the chemical effect including that alkaline oxide, like Al2O3 and CaO could dissolve from the SDS and further participate into the hydration also plays a significant role in the strength development of the composite. The micro-morphology that the SDS particles and matrix pastes were chemically bonded with no distinct Interfacial transition zone observed also verified this. These both indicated that SDS could be used as a kind of supplementary cementitious material, rather than merely as a kind of inert admixture. Finally, the space coordination theory was applied to further illustrate the reason why 10 % is the optimal dosage. This research provides an approach of utilizing the DS in CBM industry with a more effective way.

Effects of electron beam irradiation pretreatment on the substitution degree, multiscale structure and physicochemical properties of OSA-esterified rice starch

In order to investigate the effect of electron beam irradiation (EBI) pretreatment on the structure and physicochemical properties of octenyl succinic acid (OSA) esterified rice starch. In this study, rice starch was pretreated with EBI (2, 4, 6 KGy) followed by OSA esterification (3%, 6%). EBI pretreatment significantly increased the OSA-esterified starch's degree of substitution (0.0173–0.0305). However, the relative crystallinity of OSA-esterified starch decreased after EBI pretreatment. And the peak viscosity, trough viscosity and final viscosity of starch decreased significantly with the increase in irradiation dose. Moreover, EBI pretreatment significantly reduced gelatinization temperature and B3 chain content of OSA-esterified starch, and significantly increased transparency, solubility, swelling power and A chain content. In addition, OSA-esterified starch's RDS content decreased and RS + SDS content increased after EBI pretreatment. The PCA results suggest that EBI may affect the physicochemical properties of starch by acting on its structure. The results showed that EBI pretreatment improved the physicochemical and functional properties of OSA-esterified starch, which is expected to broaden its application scope.

The usage of sourdough powder as the natural preservative and glycemic index lowering agent in salty muffins

PurposeThe article aimed to use sourdough powder as a natural preservative against mould growth and a glycemic index reducer agent.Design/methodology/approachIn this study, muffin production was carried out with sourdough powder addition at the rate of 0, 15 and 30%. To obtain the sourdough powder, sourdough was fermented by using Lactobacillus fermentum, Lactococcus lactis (previously isolated from spontaneous sourdough) and Saccharomyces cerevisiae.FindingsThe specific volume, number of crumb pores and total pore area were not adversely affected by the addition of 15% or 30% sourdough powder (p > 0.05). The sourdough addition reduced the L* values of the muffin crust, while the b* value of the muffin crumb with 30% sourdough powder decreased compared to the control (p < 0.05). The addition of sourdough powder decreased eGI and RDS values and increased SDS content of samples (p < 0.05). In storage, the mould growth was observed in the control group and samples containing 15% sourdough powder on the 5th day, while the samples containing 30% sourdough powder were moulded on the 7th day. The sourdough powder increased the hardness and chewiness values of samples (p < 0.05), while it had no significant effect on springiness, cohesiveness and resilience (p > 0.05).Originality/valueThe sourdough powder provides a lower glycemic index and longer microbial shelf life that makes the product advantageous in consumer demand. This is the first time sourdough powder has been used to achieve this purpose.

Association of High-Molecular-Weight Glutenin Subunits with Grain and Pasta Quality in Spring Durum Wheat (Triticum turgidum spp. durum L.)

Spring durum wheat is an important raw material for producing diverse products such as couscous, bulgur, bread, and pasta. The quality of the dough is significantly influenced by high-molecular-weight glutenins, the allelic status of which depends on the region and breeding program. In this study, a collection of 69 cultivars and promising lines of durum wheat were analyzed for the allelic state of Glu-A1 and Glu-B1 using SDS-PAGE and KASP PCR markers. Protein and gluten content, volume increase index, pasta breaking strength, general pasta estimation, SDS, and gluten index were measured for each accession based on a two-year field experiment in the Krasnodar region. The analysis revealed that the Glu-B1al, Glu-B1d, and Glu-B1z* alleles positively influence gluten index, with Glu-B1al increasing protein, gluten, and SDS content, whereas Glu-B1d decreased these traits. Glu-B1e, on average, decreased the gluten index and SDS value but did not affect protein or gluten content. The role of alleles affecting the gluten index and protein content in ensuring the quality of pasta in durum wheat breeding is discussed.

Analysis of Peptides and Proteins by Native and SDS Capillary Gel Electrophoresis Coupled to Electrospray Ionization Mass Spectrometry via a Closed-Circuit Coaxial Sheath Flow Reactor Interface.

A simple and widely applicable coaxial sheath flow reactor interface (CSFRI) is introduced for easy and robust connection of liquid-phase microseparation methods to mass spectrometric detection, especially for capillary gel electrophoresis analysis of proteins and peptides including SDS-protein complexes. The interface readily accommodated post-column reactions prior to MS detection. It was demonstrated that this novel closed-circuit connection allowed the utilization of non-MS friendly buffer components without significant ion suppression and supported stable electrospray. In SDS capillary agarose gel electrophoresis mode, addition of γ-cyclodextrin to the sheath liquid efficiently removed the SDS content of the sample and the background electrolyte in the flow reactor section by inclusion complexation, while maintaining good separation efficiency and decreasing ion suppression.

Introducing Aliphatic Fluoropeptides: Perspectives on Folding Properties, Membrane Partition and Proteolytic Stability.

A de novo designed class of peptide-based fluoropolymers composed of fluorinated aliphatic amino acids as main components is reported. Structural characterization provided insights into fluorine-induced alterations on β-strand to α-helix transition upon an increase in SDS content and revealed the unique formation of PPII structures for trifluorinated fluoropeptides. A combination of circular dichroism, fluorescence-based leaking assays and surface enhanced infrared absorption spectroscopy served to examine the insertion and folding processes into unilamellar vesicles. While partitioning into lipid bilayers, the degree of fluorination conducts a decrease in α-helical content. Furthermore, this study comprises a report on the proteolytic stability of peptides exclusively built up by fluorinated amino acids and proved all sequences to be enzymatically degradable despite the degree of fluorination. Herein presented fluoropeptides as well as the distinctive properties of these artificial and polyfluorinated foldamers with enzyme-degradable features will play a crucial role in the future development of fluorinated peptide-based biomaterials.

Effects of rice protein, soy isolate protein, and whey concentrate protein on the digestibility and physicochemical properties of extruded rice starch.

Protein, as the second major component in starchy foods, is crucial for its influence on the physicochemical properties and digestibility of starch. However, the effect of different sources of protein on starch digestibility is still unclear. In this paper, the effects of different sources of proteins (rice protein: RP, soybean isolate protein: SPI, and whey concentrate protein: WPC) on structural features, digestibility, and enzyme activity of extruded rice starch were investigated. The addition of all three proteins reduced the starch digestibility of extrudates. Native SPI and WPC suppressed amyloglucosidase activity, and all three proteins exhibited stronger amyloglucosidase inhibition when hydrolyzed. The rheological properties and Fourier transform infrared spectroscopy results revealed the exogenous proteins and starch interacted through non-covalent bonds and improved the ordered structures in the extrudates. The extrusion process also facilitated the formation of a V-type structure. The sum of SDS and RS content of extrudates was negatively correlated with the content of leached amylose and positively correlated with the ratio of 1047/1022cm-1 . These findings suggest that the inclusion of exogenous proteins during extrusion can affect starch digestibility through mechanisms such as the interaction with starch molecules, as well as the inhibition of amylase activity. PRACTICAL APPLICATION: This result indicated that the addition of protein during extrusion not only increased the nutritional value of the extrudate, but also decreased the starch digestibility. Extrusion technology can efficiently produce extruded products with protein, expanding further applications of protein in food and providing new healthy staple food options for special populations, such as diabetic and overweight people.

Multi-Scale Structures and Functional Properties of Quinoa Starch Extracted by Alkali, Wet-Milling, and Enzymatic Methods.

The purpose of this study is to investigate the effects of starch extraction methods (alkali, wet-milling, and enzymatic) on the multi-scale structures and functional properties of quinoa starch. When the enzymatic method was compared with alkali and wet-milling, it showed higher protein content (2.4%), larger mean size of aggregated granules (44.1 μm), higher relative crystallinity (29.0%), scattering intensity (17.8 α.u.), absorbance ratio of 1047/1022 (0.9), single and double helical content (8.2% and 23.1%), FWHM ratio (1.5), and average molecular weight and radius of gyration (1.58 × 107 g/mol and 106.8 nm), respectively. Similarly, quinoa starch by enzymatic extraction had a higher onset (82.1 °C), peak (83.8 °C), and conclusion (86.3 °C) temperatures, as well as an enthalpy change (6.8 J/g). It further showed maximum hardness (238.8 N), gumminess (105.6 N), chewiness (80.2 N), SDS content (7.5% of raw and 4.8% of cooked), and RS content (15.4% of raw and 13.9% of cooked), whereas it contained minimum RDS content (77.1% of raw and 81.9% of cooked). The results suggest that extraction of starch by the enzymatic method could be a viable approach to retain the native structure of starch and may eventually improve the glycemic response.

Dual-Structure PVDF/SDS Nanofibrous Membranes for Highly Efficient Personal Protection in Mines.

Pneumoconiosis in miners is considered a global problem. Improving the performance of individual protective materials can effectively reduce the incidence of pneumoconiosis. In this study, the blend membrane of sodium dodecyl sulfate and polyvinylidene fluoride with a dual structure was prepared using electrospinning techniques, and the morphological structure, fiber diameter, and filtration performance of the nanofiber membranes were optimized by adjusting the PVDF concentration and SDS content. The results show that the incorporation of SDS enabled the nanofiber membranes to show tree-like and beaded fibers. Compared with the original PVDF membrane, the small content of tree-like fibers and beaded fibers can improve the filtration efficiency and reduce the resistance of the fiber membrane. The prepared nanofiber membrane has excellent comprehensive filtration performance, and the quality factor is 0.042 pa−1 when the concentration of PVDF is 10 wt% and the addition of SDS is 0.1 wt%. Furthermore, after high-temperature treatment, the membrane could still maintain good filtration performance. The PVDF/SDS blend nanofiber membrane has outstanding filtration efficiency and good thermal stability and can fully meet the personal protection of miners in underground high-temperature operation environments.

Processing, digestion property and structure characterization of slowly digestible gorgon nut starch.

The online version contains supplementary material available at 10.1007/s10068-021-01007-6.

Rearranged supramolecular structure of resistant starch with polymorphic microcrystals prepared in high-solid enzymatic system

Resistant starch (RS) is widely used as a new type of dietary fiber, but it is still a limitation of controllable formation of microstructure and polymeric architecture for preparing single-component RS (pure-phase). In this study, RS was prepared using maize starch with two ratios of amylose to amylopectin (RAA1:1 and RAA1:2) and four pullulanase concentrations (5, 15, 25, 35 U/g) in a high-solid dynamic reaction environment of bio-extrusion. Based on the long- and short-range orders reflected by the glycosidic bonds (13C NMR), chain-length distributions (SEC/FACE), single-/double-helices (FTIR), lamellas (SAXS) and crystalline pattern (XRD), the rearranged supramolecular structure of starch and their relationships with physicochemical properties (DSC and RVA) was illuminated. There were two morphologies of RS were created: 1) disordered fusion-like structure displayed by RAA1:1-P15 and RAA1:2-P35, which had the high contents of RS (54.95 and 54.19%) and short amylopectin (DP ≤ 24) (70.52% and 60.20%). The short (A chains) and extremely short (DP < 6) amylopectin could contribute to form submicro-crystallite with B1 chains in the extruded matrix at a low moisture level; 2) thinner, scalier and layered-like structure displayed by RAA1:2-P15 that was the transition state from thick layered strips of large granules. Its SDS content was high (33.61%) and owned the larger rearranged dLorentz (16.97 nm). Overall, the entangled regime of amylose and amylopectin in the modifications of starch with different structural units or micro-domains in this study will provide a new idea and reference to explore the preparation of novel RS.

Effects of heat moisture treatment on the structural, physicochemical and digestibility properties of potato starch–soybean peptide complexes

SummaryIn this study, potato starch (PS) was complexed with soybean peptides (SPTs) with different molecular weights under heat moisture treatment (HMT) at different moisture contents. The results showed that PSSPT complexes formed under HMT were characterised by weaker and fuzzier polarised cross patterns, and more agglomerates. After HMT, higher gelatinisation temperatures and lower enthalpies were observed for PSSPT complexes. In particular, higher gelatinisation temperatures were observed when moisture levels were higher during HMT. Compared with physically mixed counterparts, the PSSPT complexes under HMT displayed higher pasting temperatures and lower swelling power, and peak viscosity. Higher moisture content during HMT led to a less thermodynamically stable B‐polymorphic structure converting to a more stable A‐type polymorph. Higher SDS content was found in the PSSPT complexes subjected to HMT with lower moisture content, while relatively higher RS content was associated with higher moisture content of HMT. These results could be attributed to restructuring of the amylose/amylopectin chains, the physical barrier of SPT and interactions between the negatively charged groups in PS and the side chains in SPT. This study will advance our understanding of food multicomponent interactions, as well as guidance for the application development of low‐glycaemic index foods containing SDS and RS in the field of fine food processing.

Effect of removal of endogenous non-starch components on the structural, physicochemical properties, and in vitro digestibility of highland barley starch

Highland barley (HB) is a kind of slow-digesting grain. The effects of endogenous non-starch components on the digestibility of highland barley starch (HBS) are worth exploring. In this study, the effects of non-starch components on the structure, physicochemical and digestibility of HBS were studied by removing β-glucan, proteins and lipids individually and in pairs. The results showed that, all removal treatments led to an increase in the swelling power of the HBS and changes in its pasting properties, causing its easier gelatinisation and subsequent digestion. The effects of the removal of multiple components on the digestion and physicochemical properties of HBS were more significant than those corresponding to that of a single. The effect order of a single non-starch component on starch digestibility is: lipids < β-glucans < proteins. Regarding the multiple, the lowest SDS was induced by the removals of lipid and protein (actually, the protein, β-glucan and lipids were all removed), and the lowest RS was induced by the removal of proteins. The changes in the physiochemical and digestion properties caused by the removal of the non-starch components were significantly correlated; the swelling power was significantly and positively correlated with the glucose concentration at the end of digestion, and the sum of SDS and RS content was positively correlated with the ratio of 1022/995 cm−1. In conclusion, these results reveal the internal factors affecting the slow digestion characteristics of HB from the perspective of endogenous non-starch components while providing important reference values of these components in slow-digesting diets.

The Inhibitory Effects of Hericium erinaceus β-glucan on in vitro Starch Digestion.

β-glucan has attracted extensive attention due to its health promoting effects, such as lowering the blood sugar and lipids levels, and enhancing immunity. In this study, three different β-glucans (HEBG-1, HEBG-2, HEBG-3) were obtained from Hericium erinaceus by sodium hydroxide, β-1,3-glucanase and β-1,6-glucanase, respectively. The effects of the glucans on in vitro digestion of wheat starch were investigated by Englyst method. We found that addition of HEBGs significantly reduced the digestibility of starch, showing as decreased RDS and pGI, and increased SDS and RS content. In addition, the inhibitory effects positively correlated with the molecular weight of HEBG. The triple helix structure in HEBG plays important roles in inhibiting starch digestion. And β-1,3- glucan showed stronger inhibitor effects than those of β-1,6- glucan. This study unravels the mechanism of HEBG on inhibition of starch digestion and provides a theoretical understanding for the application of edible mushroom β-glucan to the development of low glycemic index starchy foods.

Effect of heat moisture treatment on rheological and in vitro digestibility properties of pearl millet starches

Pearl millet starches were modified using heat moisture treatment (HMT) (moisture content 25%, 110 °C at 3 h) and its structural and in vitro digestibility properties were studied. Amylose content, swelling power and solubility of starches were decreased after HMT. The results showed lower pasting viscosities for HMT starches as compared to native starches, thereby indicating their thermostability, and lower retrogradation capacity. G' values during heating and frequency sweep decreased after HMT. Yield stress and consistency index value ranged from 3.34 to 16.10 Pa and 5.5 to 21.2 Pa.s, the lowest value was observed for cv.HHB-67 and cv.GHB-732, respectively. Steady shear properties showed flow behavior index values <1 for starch pastes, indicating pseudoplastic and shear-thinning behavior. After modification, RS and SDS content increased and RDS content decreased as compared to their native counterpart starches. After HMT modification thermal stability and nutritional value of starches improved which enhance food applications of starches.

Fabrication of fluorescent polymer latexes based on rhodamine B derivatives and their reusable films for Fe3+ detection

The stimulus-responsive P(MMA-co-BA-co-RhBUEA) latexes were prepared by miniemulsion polymerization of butyl acrylate (BA), methyl methacrylate (MMA), and a rhodamine-based probe RhBUEA. Their chemical composition and structures were characterized by FTIR and UV–Vis spectral analysis. Meanwhile, the effects of AIBN, SDS, and RhBUEA content on the miniemulsion polymerization and the morphology of latex particles were investigated. Based on the recipe of 30 mM SDS to the volume of water, 2 wt% AIBN and 5 wt% RhBUEA to the total monomers, the sensing properties of the resultant latex and its film were studied. Both the latex and the latex film displayed the noticeable color change, high sensitivity, superior selectivity, and anti-interference properties towards Fe3+ over other metal ions in aqueous solution. The detection limits of the latex and the latex film were 0.122 and 0.208 μM, respectively. Furthermore, the film sensor exhibited good recyclability thanks to the off-on switch, possessing the potential as a portable and reversible chemosensor for the naked-eye detection of Fe3+.