Impact of sage seed gum and whey protein concentrate on the functional properties and retrogradation behavior of native wheat starch gel

Effect of non-starch components in liangpi slurry on thermal and rheological properties of concentrated wheat starch gels

Liangpi, a traditional Chinese cold skin noodle, primarily consists of wheat starch in a concentrated gel system. However, high-quality liangpi cannot be solely produced with pure wheat starch. The effects of endogenous non-starch components in liangpi slurry (LPS) on wheat starch properties were investigated by mixing LPS with wheat starch slurry (WSS) in various LPS/WSS ratios. Results showed that increasing LPS/WSS ratios significantly enhanced the swelling power and water-holding capacity at 70 °C and 90 °C. The gelatinization onset temperature of LPS/WSS samples rose from 80.5 °C for pure WSS to 83.3 °C for LPS. The peak viscosity of LPS was more than three times higher than that of WSS, and the breakdown viscosity also increased with the incorporation of non-starch components. In concentrated systems, the storage modulus (G') and loss modulus (G") of the resultant gels gradually increased with higher LPS/WSS ratios. However, gel fluidity, frequency dependence of G', and gel hardness do not exhibit a linear relationship with LPS/WSS ratios, reaching their maximum values at LPS/WSS ratios of 6:4 or 4:6. Their trends were also similar to gel cohesiveness and the critical strain under large amplitude oscillatory shear. This suggested that non-starch components improved small deformation properties but compromised gel stability under large deformations. This was further evidenced by Lissajous curves evolution of LPS gels, with LPS gels showing higher strain hardening coefficient, shear thinning coefficient, and harmonic ratio compared to WSS gels. This study points the way for future research to identify the specific non-starch component that matters.

Soybean protein isolate/dialdehyde sodium alginate hydrogels based on dynamic imine bond cross-linking: Synthesis and properties

A soybean protein isolate (SPI)-based hydrogel with controllable properties was prepared under mild conditions using a simple mixing method with dialdehyde sodium alginate (DSA) as an eco-friendly macromolecular crosslinker. DSA was successfully synthesized via periodate oxidation. Analysis of the structure of the SPI/DSA hydrogel indicated that a 3D network was formed between SPI and DSA through dynamic imine and hydrogen bonds. The analysis of the physicochemical properties of the hydrogels showed that the micropore size, mechanical properties, and the swelling and release behavior of the hydrogels could be effectively regulated by changing the DSA content. When 3.0 wt% DSA was added, the hydrogel exhibited a dense and homogeneous network structure with optimal gel properties, which enabled the controlled release of curcumin. This effective structure is mainly attributed to the synergistic effect of short- and long-range chemical and physical crosslinking. Overall, the SPI/DSA hydrogels are effective carriers for the controlled release of bioactive compounds.

Effect of four highland barley proteins on the retrogradation and in vitro digestion properties of highland barley starch

This study evaluated the effects of four highland barley proteins (HBPs), namely albumin, globulin, gliadin and glutenin, on the retrogradation and in vitro digestion properties of highland barley starch (HBS). The results showed globulin had the most significant effect on inhibiting short-term retrogradation of HBS, which was reflected in the reduction of G' and G". Compare with HBS, four HBPs could significantly inhibit long-term recrystallization process. For albumin, globulin, gliadin and glutenin, the degree of retrogradation reduced from 51.55 % to 48.20 %, 35.06 %, 42.22 % and 32.63 %, respectively, which was reflected in the decrease of water migration rate, crystal enthalpy, crystallinity and short-range order. It could be found that glutenin had the most significant effect on inhibiting long-term retrogradation of HBS. Moreover, the anti-digestion properties of retrograded HBS with HBPs intervention significantly increased, with glutenin most significantly. Compared with HBS, resistant starch (RS) content increased by 59.76 % at 28 d of retrogradation.

Integrative experimental and computational analysis of the impact of KGM's polymerization degree on wheat starch's pasting and retrogradation characteristics

This study investigated the influence of Konjac Glucomannan (KGM) with varying degrees of polymerization (DKGMx) on the gelatinization and retrogradation characteristics of wheat starch, providing new insights into starch-polysaccharide interactions. This research uniquely focuses on the effects of DKGMx, utilizing multidisciplinary approaches including Rapid Visco Analysis (RVA), Differential Scanning Calorimetry (DSC), rheological testing, Low-Field Nuclear Magnetic Resonance (LF-NMR), and molecular simulations to assess the effects of DKGMx on gelatinization temperature, viscosity, structural changes post-retrogradation, and molecular interactions. Our findings revealed that higher degrees of polymerization (DP) of DKGMx significantly enhanced starch's pasting viscosity and stability, whereas lower DP reduced viscosity and interfered with retrogradation. High DP DKGMx promoted retrogradation by modifying moisture distribution. Molecular simulations revealed the interplay between low DP DKGMx and starch molecules. These interactions, characterized by increased hydrogen bonds and tighter binding to more starch chains, inhibited starch molecular rearrangement. Specifically, low DP DKGMx established a dense hydrogen bond network with starch, significantly restricting molecular mobility and rearrangement. This study provides new insights into the role of the DP of DKGMx in modulating wheat starch's properties, offering valuable implications for the functional improvement of starch-based foods and advancing starch science.

Effect of three polysaccharides with different charge characteristics on the properties of highland barley starch gel

Highland barley, a nutritious whole grain, faces limited market utilization due to the poor heating stability of its starch. The aim of this study was to investigate the effects of three differently charged ionic polysaccharides-guar gum (GG), xanthan gum (XG), and carboxymethyl chitosan (CMC)-on the gel properties of highland barley starch (HBS). GG and XG notably increased pasting viscosity, viscoelasticity, hardness, and strength of HBS gels. Conversely, CMC resulted in decreased gel properties. All three polysaccharides enhanced OH tensile vibration (3000-3800 cm-1), with GG and XG promoting denser honeycomb network structures and lower spin-spin relaxation time (T2), indicating improved structural integrity. In contrast, low concentrations of CMC led to disorder and loose structure. Hydrogen bonding and electrostatic interactions were the main forces by which polysaccharides influenced the properties of starch gels. This research contributes to enhancing the properties of HBS gel during heating and expanding its commercial applications. It also provides some insights to understand the interaction between different charged polysaccharides and starch.

Enhancing mucoadhesion: Exploring rheological parameters and texture profile in starch solutions, with emphasis on micro-nanofiber influence

This comprehensive analysis explores the rheological parameters and texture profile analysis (TPA) to effect starch solutions for mucoadhesion and assess the impact of micro-nanofibers (MNFs) on these parameters. The surface chemistry of all six samples was examined through the Fourier transform infrared (FTIR) technique. The spectrum of FTIR was recorded in the range of 500-4000 cm-1. The viscosity of different pHs (2-11) and temperatures (20-70 °C) of verious starches, potato, corn, and rice, decreased with the increasing of shear rate, exhibiting shear thinning behavior, which conformed to pseudoplastic fluid.The combination of chitosan and collagen MNFs significantly changed rheological properties, and the sample with the addtion of 1500 µL CC-MNF exhibited a greater viscosity of 59.8 mPa·s at a shear rate of 1.49 s-1. Potato starch emerged as a strong candidate for mucoadhesion due to its low hardness (4.62 ± 0.31 N), high adhesion (0.0322 ± 0.0053 mJ), cohesiveness (0.37 ± 0.03 Ratio), low chewiness (0.66 ± 0.12 mJ), and gumminess (1.69 ± 0.23 N). The inclusion of MNFs, especially collagen/chitosan MNFs showed the potential to further enhance adhesion.

Effects of synergistic modification using alkalis and guar gum on the pasting, rheological, and microstructural properties of germinated highland barley starch gels

Germination treatment of highland barley enhances its nutritional value while weakening the starch gel properties. This study aims to enhance the characteristics of germinated highland barley starch (GBS) by exploring the synergistic effects of two alkalis (Na2CO3 and NaHCO3) and guar gum (GG) on GBS gel properties. The combined action of alkalis and GG significantly improved the peak viscosity, setback viscosity, and hardness compared with GG alone. The highest G' and G" reached 998 and 204 Pa at 0.4% Na2CO3 addition, which were increased by nearly 44% and 50%, respectively. Fourier-transform infrared spectral analysis revealed that the alkalis strengthened interaction forces, particularly with intensified absorption peaks at 3200-3700 cm-1 and 1550-1750 cm-1. The Na2CO3 and NaHCO3 reduced the spin-spin relaxation time (T2), resulting in a dense starch gel network. This study contributes to enhancing the market application of GBS and offers innovative insights for modifying other starches.

A comparative study on the gel and structural characteristics of starch from three rice varieties when combined with Mesona chinensis polysaccharides

Mesona chinensis polysaccharide (MCP) has excellent gel-forming characteristic, previous studies showed that MCP could affect the gelling and structural properties of rice starch, but the effect of MCP on rice starch from different types is not clarified. In this study, the effects of MCP on the pasting, rheological, and structural characteristics of glutinous rice starch (GRS), japonica rice starch (JRS), and indica rice starch (IRS) were investigated. The results showed that GRS-MCP has the best viscosity, its peak and final viscosities are higher than JRS-MCP and IRS-MCP. The gel network structure was enhanced by MCP in the order of IRS > JRS > GRS, which was reflected by greater elasticity, higher gel strength and hardness, and less free water in JRS-MCP and IRS-MCP. MCP also enhanced the ordered structure and thermal stability of the three starch gels, which is conducive to their application in the market. These findings provide new theoretical insights to produce rice starch-based foods.

Combined effect of heat moisture and ultrasound treatment on the physicochemical, thermal and structural properties of new variety of purple rice starch

The advantages of physically modifying starch are evident: minimal environmental impact, no by-products, and straightforward control. The impact of dual modification on starch properties is contingent upon modification conditions and starch type. Herein, we subjected purple rice starch (PRS) to heat-moisture treatment (HMT, 110 °C, 4 h) with varying moisture content, ultrasound treatment (UT, 50 Hz, 30 min) with different ultrasonic power, and a combination of HMT and UT. Our findings reveal that UT following HMT dispersed starch granules initially aggregated by HMT and resulted in a rougher granule surface. Rheological analysis showcased a synergistic effect of HMT and UT, enhancing the fluidity of PRS and reinforcing its resistance to deformation in paste form. The absorbance ratio R1047/1015 indicates that increased moisture content during HMT and high ultrasound power for UT reduced the short-range order degree (1.69). However, the combined HMT-UT exhibited an increased R1047/1015 (1.38-1.64) compared to HMT alone (1.29-1.45), likely due to short-chain rearrangement. Notably, the A-type structure of PRS remained unaltered, but overall crystallinity significantly decreased (23.01 %-28.56 %), consistent with DSC results. In summary, physical modifications exerted significant effects on PRS, shedding light on the mechanisms governing the transformation of structural properties during HMT-UT.

Assembly of soy protein-corn starch composite gels by thermal induction: Structure, and properties

The effect of different corn starch (CS) concentrations on the gel formation of soybean isolate protein (SPI) was investigated. Moreover, the texture, rheological properties of the gel were determined, and the spatial structure and interactions of the composite gel system were analyzed. The composite system transitioned from liquid to solid-like with an increase in the CS concentration and did not backflow when inverted for 24 h. With the addition of CS, the gel strength, water holding capacity (WHC), G', and G'' increased significantly. The maximum was reached at 10 % starch concentration with gel strength of (228.96 ± 29.86) g and WHC of (98.93 ± 2.02)  %. According to low-field 1H nuclear magnetic resonance (LF-NMR) results, CS has a high water absorption capacity, which improved the WHC. The scanning electron microscopy results revealed that composite gels with a high CS concentration had a more dense and small void network structure. According to the results of molecular force interaction, infrared spectroscopy, Raman spectroscopy, and free sulfhydryl group analysis, the added starch promoted the unfolding of SPI molecules, exposure of hydrophobic groups, transformation of free sulfhydryl groups into disulfide bonds, and hydrogen bond formation. Hydrophobic interactions, disulfide bonding, and hydrogen bonding function together to form the SPI-CS composite gel system. The study results provide the basis for applying soy protein and CS gels.

The effects of different hydrocolloids on lotus root starch gelatinization and gels properties

In this study, xanthan gum (XG), sodium alginate (SA), guar gum (GG), and gum Arabic (GA), were used to modify Lotus root starch (LRS). The incorporation XG, SA, and GG significantly (p < 0.05) influence the swelling power (SP) of LRS, among which the 1.5 % of XG exhibited the highest value of 25.84 g/g at 90 °C. Gelatinization analysis revealed that XG raised the final viscosity (FV) and lowered the breakdown (BD), while SA significantly increased peak viscosity (PV) and BD. Furthermore, GG and GA exhibited a substantial reduction in setback (SB). The incorporation of XG, SA, and GG enhanced the rheological and structural properties (e.g., gel strength and elasticity) of LRS. Particularly, XG demonstrated a more prominent effect, while GA exhibited an opposite trend. Moreover, the structural analyses revealed that hydrophilic colloids have no impact on the functional group and crystal structure of the LRS. However, complex system exhibited the more stable hydrogen bonding. The addition of 1.5 % XG exhibited the most stable hydrogen bonding and highest water binding affinity. Overall, the results demonstrated the effect of different hydrophilic colloids on LRS, offering a theoretical basis for LRS applications and novel insights for the use of starches and hydrocolloids.

Fabrication and rheological properties of a novel interpenetrating network hydrogel based on sage seed hydrocolloid and globulin from the hydrocolloid extraction by-product

In this study, interpenetrating polymer network hydrogels were developed based on sage seed gum (SSG) and globulin protein (Glo) extracted from the mucilage-free seeds. By combining Glo hydrogel with the SSG network the inherent weak gelation of the single SSG system was compensated. As the fraction of Glo increased, various properties of the interpenetrating polymer network (IPN) hydrogels improved substantially. Electrophoretic analysis under reducing conditions showed that Glo dissociated into subunits of approximately 30 kDa and 20 kDa, suggesting it comprises 11S globulin. FTIR spectrum revealed new peaks at 1645 cm-1 and 1537 cm-1 in the amide I and II regions, respectively, for the IPN hydrogels, indicating interactions between two hydrogel networks. Based on the weight loss measurements, the IPN hydrogels exhibited lower mass loss, particularly at higher Glo fractions up to 6 %. The IPN hydrogels also displayed enhanced elasticity, pseudoelasticity, thixotropy, and creep resistance compared to SSG hydrogel, indicating suitability for food, pharmaceutical, and biomedical applications. More broadly, this research provides a sustainable strategy toward innovative material development while advancing bio-based hydrogels.

Research progress in extraction, purification, structure of fruit and vegetable polysaccharides and their interaction with anthocyanins/starch

Fruits and vegetables contain polysaccharides, polyphenols, antioxidant enzymes, and various vitamins, etc. Fruits and vegetables polysaccharides (FVPs), as an important functional factor in health food, have various biological activities such as lowering blood sugar, blood lipids, blood pressure, inhibiting tumors, and delaying aging, etc. In addition, FVPs exhibit good physicochemical properties including low toxicity, biodegradability, biocompatibility. Increasing research has confirmed that FVPs could enhance the stability and biological activities of anthocyanins, affecting their bioavailability to improve food quality. Simultaneously, the addition of FVPs in natural starch suspension could improve the physicochemical properties of natural starch such as viscosity, gelling property, water binding capacity, and lotion stability. Hence, FVPs are widely used in the modification of natural anthocyanins/starch. A systematic review of the latest research progress and future development prospects of FVPs is very necessary to better understand them. This paper systematically reviews the latest progress in the extraction, purification, structure, and analysis techniques of FVPs. Moreover, the review also introduces the potential mechanisms, evaluation methods, and applications of the interaction between polysaccharides and anthocyanins/starch. The findings can provide important references for the further in-depth development and utilization of FVPs.

Retrogradation inhibition of wheat starch with wheat oligopeptides

Starch staling greatly reduces the cereal products quality, and the staling retardation becomes a focus in current research. The effect of wheat oligopeptide (WOP) on anti-staling properties of wheat starch (WS) was studied. Rheology property indicated that WOP reduced WS viscosity, showing more liquid-like behavior. WOP improved the water holding capacity, inhibited swelling power, and reduced the hardness of WS gels, which decreased from 1200 gf to 800 gf compared with the control after 30 days storage. Meanwhile, the water migration of WS gels were also reduced with WOP incorporation. The relative crystallinity of WS gel with 1% WOP was reduced by 13.3%, and the pore size and the microstructure of gels was improved with WOP. Besides, the short-range order degree reached the lowest value with 1% WOP. In conclusion, this study explained the interaction between WOP and WS, which was beneficial to the application of WOP in WS-based food.

Effects of high temperature, high humidity, and cold storage on structure and qualities of whole oat flour noodles during processing

Gelation and structure of oat starch significantly affect qualities of whole oat flour noodles. During extrusion, the structure of noodles is loose, resulting in high cooking loss and poor texture. Therefore, oat noodles were treated with high temperature, high humidity (HTH), and cold storage (CS), and their structure and qualities were analyzed. The results showed that compared with CS, HTH could reduce the cooking loss of noodles from 10.12% to 6.13%, increase the hardness (65.59 g) and chewiness (20.67) of noodles, and effectively improve the sensory quality of noodles. The change in texture and sensory of noodles was due to HTH by accelerating the retrogradation of starch in noodles, promoting the cross-linking of starch molecules to form an ordered structure, causing an increase in the ordered degree and crystallinity of starch and making the structure of noodles denser. It made the mobility of water in the noodles decrease, and more tightly bound water was transformed into weakly bound water and free water. HTH can be applied to industrial production of whole oat flour noodles. This study could effectively guide the production of high-quality whole oat flour noodles without any food additives.

The effects of Mesona chinensis Benth gum on the pasting, rheological, and microstructure properties of different types of starches

The effect of Mesona chinensis Benth gum (MCG) on pasting, rheological and texture properties of different types of starches (tubers, cereals, and beans) were investigated. Pasting results showed that the pasting temperatures (PT) of native cereal and beans starch were higher, and MCG decreased the PT of starch granules by competing water with starch granules for water. MCG increased the peak viscosity and breakdown viscosity of native starches except potato starch, and effectively promoted the short-term retrogradation of all kinds of starches. Rheological results also revealed MCG increased apparent viscosity and dynamic modulus of native starch gels, given that the compacter network structures could be formed after adding MCG. The compacter network structures also contribute to the enhancement of gel strength and hardness, and the decreased spin relaxation time of starch gels. The information provided in this paper could help people to understand the different effects of MCG on the various starch, which had certain significance for starch-MCG product development.

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Comparatively investigated the effects of MCG on tuber, cereal, and bean starch.

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MCG promoted the short-term retrogradation of native starches.

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Gel strength and water binding capacity of starches were enhanced after adding MCG.

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MCG effectively strengthened the network structure of starch gels.

Development of a Multifunctional Edible Coating and Its Preservation Effect on Sturgeon (Acipenser baeri♀× Acipenser schrenckii♂) Fillets during Refrigerated Storage at 4 °C

Although many coatings and films can improve the quality and shelf life of fish fillets during refrigerated storage, a more multifunctional coating material is needed. In this study, an edible alginate/protein-based coating solution was prepared by incorporating antimicrobial agents. The coating properties were characterized and its effects on the quality and shelf life of sturgeon fillets during refrigeration (4 °C) were investigated. Compared with sodium alginate coating (2% sodium alginate + antibacterial agents, H), the composite coatings (2% sodium alginate + antibacterial agents + 1:15 or 1:10 protein solution, HP-15 and HP-10) exhibited a more stable structure and better light, gas, and water barrier properties, and showed better quality-preservation effects on sturgeon fillets. The composite coatings treatments, especially HP-10 composite coating, exhibited significant (p < 0.05) effects in inhibiting microbial growth, maintaining sensory quality, reducing the production of total volatile basic nitrogen (TVB-N), decreasing nucleotide breakdown, and delaying the lipid oxidation and protein degradation in fillets. These findings confirm that the composite coatings can be used as a multifunctional coating material for freshness preservation of sturgeon fillets to improve quality and extend shelf life.

Physicochemical, Pasting, and Thermal Properties of Native Corn Starch-Mung Bean Protein Isolate Composites

Starch is widely used in food and non-food industries because of its unique characteristics. However, native starch shows some weaknesses that restrict its applications. Recently, some studies have demonstrated the benefits of using protein to overcome these limitations. Therefore, the aim of the present study was to investigate the effect of mung bean protein isolate (MBPI) (2%, 4%, 6%, and 8%) on the physicochemical, pasting, and thermal properties of native corn starch (NCS), as a novel starch-protein composite. Higher swelling power (SP), water absorbance capacity (WAC), and solubility values of NCS were observed with increasing MBPI concentration. Additionally, by the addition of MBPI, the rapid visco analyzer (RVA) showed a reduction in pasting temperature (77.98 to 76.53 °C), final viscosity (5762 to 4875 cP), and setback (3063 to 2400 cP), while the peak viscosity (4691 to 5648 cP) and breakdown (1992 to 3173 cP) increased. The thermal properties of NCS/MBPI gels investigated by differential scanning calorimetry (DSC) showed higher onset, peak, and conclusion temperatures (69.69 to 72.21 °C, 73.45 to 76.72 °C, and 77.75 to 82.26 °C, respectively), but lower gelatinization enthalpy (10.85 to 8.79 J/g) by increasing MBPI concentration. Fourier transform infrared spectroscopy (FT-IR) indicated that the addition of MBPI decreased the amount of hydrogen bonds within starch. Furthermore, after three cycles of freeze-thaw shocks, the syneresis of NCS-MBPI composites decreased from 38.18 to 22.01%. These results indicated that the MBPI could improve the physicochemical properties of NCS, especially its syneresis and retrogradation characteristics.

Impact of Konjac Glucomannan with Different Molecular Weight on Retrogradation Properties of Pea Starch

The impact of konjac glucomannan (KGM) with different molecular weight (Mw) on the retrogradation properties of pea starch, such as color, viscoelasticity, gel strength, water holding capacity (WHC), moisture distribution and crystallinity, was investigated. At the same time as the Mw of KGM decreased, the lightness, elastic modulus, gel strength, water freedom and crystallinity of pea starch showed an increasing trend, whereas the viscosity modulus and WHC showed a decreasing trend. At one day of storage, compared with single pea starch, KGM with low Mw made gel strength increase from 40 g to 45 g, WHC decrease from 82% to 65% and crystallinity increase from 21.3% to 24.0%. Therefore, KGM with low Mw could promote retrogradation of pea starch in the short-term. At 7 days or even 14 days of storage, KGM with medium-high Mw had smaller indices than those of pure pea starch, including the lightness, storage modulus, gel strength, water freedom and crystallinity. This indicated that KGM with medium-high Mw could inhibit the long-term retrogradation of starch. The larger the Mw of KGM, the more noticeable the inhibition effect.

Gallic acid and heat moisture treatment improve pasting, rheological, and microstructure properties of Chinese yam starch-chitosan gels: A comparative study

Nowadays，It is difficult for the polysaccharide-starch system to meet demand of practical production owing to the poor gel properties. Therefore, aiming to further improve the practical application of polysaccharide-starch gel, the effects of gallic acid (GA) and heat moisture treatment (HMT) on the gel properties and microstructure of yam starch/chitosan (YS/CS) composite gels were investigated. Swell power (SP) results showed that GA and HMT treatment respectively reduced the SP of YS gel by 3.24 g/g and 6.03 g/g, given that GA and HMT decrease the rheology of the water phase inhibiting the entry of water into the swollen starch. In the pasting process, HMT reduced pasting viscosity of the HMT/YS system because only little amylose was leached in the medium for elevating its viscosity after HMT. The rheological properties suggested that high temperature treatment of HMT facilitated the disruption and disintegration of starch granules resulting dynamic modulus had a decline trend. The elastic properties of GA/YS gels were enhanced with the addition of GA, which could be supported by the thicken lamellar observed in its microstructure. In general, GA and HMT effectively alter the gel properties of YS/CS gel system, and facilitate its practical application in food industry.

Effects of Mung Bean (Vigna radiata) Protein Isolate on Rheological, Textural, and Structural Properties of Native Corn Starch

It is critical to understand the starch–protein interactions in food systems to obtain products with desired functional properties. This study aimed to investigate the influence of mung bean protein isolate (MBPI) on the rheological, textural, and structural properties of native corn starch (NCS) and their possible interactions during gelatinization. The dynamic rheological measurements showed a decrease in the storage modulus (G’) and loss modulus (G”) and an increase in the loss factor (tan δ), by adding MBPI to NCS gels. In addition, the textural properties represented a reduction in firmness after the addition of MBPI. The Scanning electron microscope (SEM) images of the freeze-dried NCS/MBPI gels confirmed that the NCS gel became softer by incorporating the MBPI. Moreover, X-ray diffraction (XRD) patterns showed a peak at 17.4°, and the relative crystallinity decreased with increasing MBPI concentrations. The turbidity determination after 120 h refrigerated storage showed that the addition of MBPI could reduce the retrogradation of NCS gels by interacting with leached amylose. Additionally, the syneresis of NCS/MBPI gels decreased at 14 days of refrigerated storage from 60.53 to 47.87%.

Quinoa flour as a skim milk powder replacer in concentrated yogurts: Effect on their physicochemical, technological, and sensory properties

Milk standardization with solids (i.e., nonfat milk solids, MSNF) for yogurt manufacture is traditionally achieved by the addition of skim milk powder (SMP). However, the addition of SMP to milk‐based yogurt increases lactose content and decreases both protein content and gel firmness. Thus, in this work, quinoa flour (QF; 0%, 25%, 50%, 75%, and 100% w/w) was used to replace SMP in concentrated yogurt. The physicochemical, textural, and sensory properties and microstructure of the yogurt were evaluated during cold storage. Generally, protein content, water‐holding capacity, and L* value decreased, while syneresis, textural attributes, and viscosity increased with increasing QF content. The substitution of high levels of QF (>25%, w/w) for SMP led to significantly shorter fermentation times, as compared to the control sample. The scanning electron microscopy observations showed significant changes in the yogurt microstructure as a consequence of QF replacement. Samples with 25% (w/w) substitution of QF and control had the highest scores in overall acceptance. According to the results, QF could be applied as an interesting raw material for concentrating the milk‐based yogurt at substitution level of 25% (w/w).

A comprehensive review of the factors influencing the formation of retrograded starch

The retrogradation of starch is an inevitable change that occurs in starchy food during processing and storage, in which gelatinized starch rearranges into an ordered state. The chain length, proportion and structure of amylose and amylopectin vary in different types of starch granules, and the process is affected by the genes and growth environment of plants. The internal factors play a significant role in the formation of retrograded starch, while the external factors have a direct impact on its structural rearrangement, and the creation of suitable conditions enables food components to affect the rearrangement of starch. Interestingly, water not only directly affects the gelatinization and retrogradation of starch, but also serves as a bridge to deliver the influence of other components that influence retrogradation. Moreover, there are three mechanisms responsible for forming retrograded starch: the migration of starch molecular chains in the starch-water mixed system, the redistribution of water molecules, and the recrystallization kinetics of gelatinized starch. In this paper, the effects of internal factors (amylose, amylopectin, food ingredients) and external factors (processing conditions) on the formation of retrograded starch and the mechanism controlling these effects are reviewed.

Ordered structural changes of retrograded starch gel over long-term storage in wet starch noodles

Temperature-induced structural variations of retrograded starch gel during long-term storage were investigated in a real food system (wet starch noodles). Fresh starch noodles presented a B-type XRD pattern containing 8.82% crystallinity and 16.04% double helices. In the first 2 weeks, double helices of starch chain formed long-range ordered structure leading to increased crystallinity, and such structural transformation was positively correlated with increasing storage temperature (from 4 °C to 35 °C) and storage time. However, with the extension of storage time to 12 weeks, the disorganization of supra-molecular structure was likely to be observed by decreased crystallinity, double helix and water mobility. Besides, we propose that the area and intensity of Raman band at 2910 cm^-1 can be a good indicator for evaluating perfection of crystallinity in starch noodles. These results contributed to a better understanding of mechanisms underlying molecular order changes of retrograded starch gel product during long-term storage.