Search

For efficient and comprehensive detection of the staling degree of Chinese steamed bread (CSB), staled CSB samples stored for 0-16 days were prepared and analyzed using near-infrared (NIR), mid-infrared (MIR), and Raman spectroscopy combined with data fusion. Among three data fusion schemes, decision-level fusion achieved the best performance when quantifying the CSB staling degree according to the soluble starch amylose fraction, relative crystallinity, and hardness, with determination coefficients and root mean square errors for the validation set in the range of 0.928-0.986 and 0.015-1.290, respectively. The relative percent deviation values of the three indicators increased to 8.362, 4.735, and 3.617, respectively. These results indicate that the combination of NIR, MIR, and Raman spectroscopy as a decision-level fusion scheme can achieve efficient, comprehensive, and accurate quantification of the staling degree of CSB. This research has important applications for food quality, safety, and shelf-life evaluations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

To shorten the preparation time of porous starch while simultaneously ensuring its adsorption performance, we treated corn starch with a combination of microwave and complex enzymatic (α-amylase and amyloglucosidase) hydrolysis. Specifically, we investigated the effect of microwave and enzymatic hydrolysis on the structure, physicochemical properties, and adsorption capability of the prepared porous starch. The results showed that the porous starch prepared by combined treatment had denser pores, no new groups were produced in the porous starch, the relative crystallinity, gelatinization temperature, and solubility increased, while the gelatinization enthalpy and swelling power decreased. Compared to enzymatic hydrolysis, the combined treatment yielded starch samples with a larger specific surface area and pore capacity, and the adsorption performance was significantly improved, with water and oil absorption rates increasing from 110.99 % and 133.11 % to 128.29 % and 143.3 %, respectively. These findings indicate that the synergistic processing of microwave and enzymatic hydrolysis has great potential as a productive and rapid method for the preparation of porous starch., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The use of plastics is resisted worldwide. Therefore, finding alternatives to plastic packaging products is an urgent issue. This work was dedicated to the preparation of biodegradable composited films with potato starch, glycerol, and gelatin. The formulation of the biodegradable film was first optimized via response surface methodology combined with the multi-index comprehensive evaluation method that considered physical properties (thickness, water solution (WS), tensile strength (TS) and elongation at break (E%)) and barrier property (light transmittance (T%)). Results indicated that the optimal conditions were 2.5% starch, 2.0% glycerol, and 1.5% gelatin (based on water). The optimized film presented excellent properties with TS of 4.47 MPa, E% of 109.91%, WS of 43.64%, and T% of 41.21% at 500 nm, and the comprehensive evaluation score of the composite film was 28.68. Moreover, a model verification experiment was further conducted, which proved that the predicted value highly matched experimental values, indicting the credibility and accuracy of the model. The resulting films were further characterized on the basis of rheological measurements, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The rheological measurements proved that the film-forming solution exhibited low shear viscosity and non-Newtonian fluid behavior. FTIR and SEM revealed excellent compatibility among starch, glycerol, and gelatin. Hence, the resulting optimized film may be expected to provide theoretical basis and technical support for the food packing industry. [ABSTRACT FROM AUTHOR]

This study explored the potential of purple potato anthocyanins (PPAs) in regulating the digestive properties of starches of various crystalline types. In vitro digestion experiments indicated that PPAs inhibit the hydrolysis of rice starch (A-type) better than that of garden pea starch (C-type) and potato starch (B-type). Further structural assessment of different PPA–starch systems showed that PPAs and starch likely interact through non-covalent bonds, resulting in structural changes. Microstructural changes observed in the starches were consistent with the in vitro digestion results, and the chain length and proportions of short/long chains in amylopectin molecules affected the binding strengths and interaction modes between PPAs and starch. Hence, the three starches differed in their PPA loading efficiency and digestibility. These discoveries contribute to a deeper understanding of the mechanisms underlying the inhibition of starch digestibility by PPAs. They can aid the formulation of value-added products and low-glycemic-index foods. [Display omitted] • PPAs could reduce starch digestibility by differentially altering the structure of the three crystalline starches. • Rice starch (A-type) had a greater ability to bind PPAs, resulting in its lowest digestibility. • The greater binding capacity between rice starch and PPAs is due to its higher content of short-chained amylopectin. [ABSTRACT FROM AUTHOR]

Starch retrogradation is a mechanism that is associated with the quality of starch-based food products; however, the molecular mechanisms underlying this process remain unclear. In this study, we analyzed starch recrystallization by measuring the degree of starch retrogradation, determining the retrogradation enthalpy, and performing scanning electron microscopy experiments. Two-dimensional correlation spectroscopy (2D-COS) was applied to Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy data to further characterize the starch-retrogradation process. We collected and preprocessed FTIR and Raman spectral data on 15 different storage days and then mapped these data using 2D-COS to analyze the ongoing composition changes in starch. Our FTIR- and Raman-2D-COS results revealed 11 and 10 quantitative peaks related to starch retrogradation, respectively. We analyzed the order of specific chemical composition and molecular changes by determining correlations between spectral variables and chemical components; moreover, using these quantitative peaks, we employed a quantitative partial least squares model to establish the degree of starch regeneration based on the retrogradation and associated enthalpy changes. The correlation coefficients of the validation set were 0.943 and 0.972, respectively. These data show that quantitative peaks obtained with 2D-COS analysis can be used to study starch retrogradation quantitatively and have implications for enhancing the quality of starch-based foods. [Display omitted] • The microstructure evolution during wheat starch retrogradation was studied. • 2D-COS was combined with infrared and Raman spectroscopy for retrogradation analysis. • The order of specific chemical composition and molecular changes were determined. • Feature peaks about starch retrogradation were identified by 2D-COS analysis. • PLS models of the degree of starch retrogradation were built based on feature peaks. [ABSTRACT FROM AUTHOR]

[Display omitted] • PRS3 was prepared by ultrasound-assisted autoclave gelatinization. • Under optimal treatment conditions, the PRS3 content increased from 7.5% to 15.9%. • The structure and gelatinization characteristics of PRS3 were studied. • The effect of PRS on the quality of steamed bread was studied. • The overall acceptance of steamed bread with 5% PRS3 was higher. In this study, we aimed to establish an innovative and efficient preparation method of potato resistant starch (PRS). To achieve this, we prepared type 3 resistant starch (RS3) from native potato starch (PS) using an ultrasonic method combined with autoclave gelatinization and optimized by the response surface method to study the structure and properties of potato RS3 (PRS3) and its effect on the quality of steamed bread. Under optimal treatment conditions, the PRS3 content increased from 7.5% to 15.9%. Compared with PS, the B-type crystal structure of PRS3 was destroyed, and the content of hydroxyl groups was increased, but no new chemical groups were introduced. PRS3 had a rougher surface and a lower crystallinity, gelatinization temperature, viscosity, setback value, and breakdown value. The low content (5%) of PRS3 had a stable viscosity and was easily degraded by bacteria, which can improve the quality of steamed bread to a certain extent. When the PRS3 content was over 10%, it competed with the gluten protein to absorb water, which reduced the contents of β-turn and α-helix in the dough, increased the contents of β-fold, and weakened the structure of the gluten network. It also decreased the specific volume and elasticity of the steamed bread and increased the spreading rate, hardness, and chewiness. Steamed bread prepared with a flour mixture containing 5% PRS3 was similar to the presidential acceptance of control flour. In this study, a new sustainable and efficient PRS3 preparation method was established, which has certain guiding significance for the processing of Functional steamed bread with high-resistant starch. [ABSTRACT FROM AUTHOR]

The phenolics from sea buckthorn (SP) exert various physiological functions. This study examined the interactions of SP on the digestive and physicochemical properties of rice (RS) and wheat starch (WS), as well as the stability of starch-phenolics during digestion. The predominant phenolics from SP were syringic acid (22.14%), gallic acid (15.23%), and catechin (11.45%). The addition of SP manipulated the rheology of starch pastes and affected the rearrangement and multi-scale structures of starch gels. Fourier transform infrared spectroscopy and X-ray diffraction revealed that SP interacted with starch mainly through non-covalent hydrogen bonds, leading to a loose starch gel structure. The content of rapidly digestible starch of RS and WS decreased by 5.66% and 7.75%; the predicted glycaemic index of RS (91.65) and WS (89.34) decreased to 81.81 and 80.84, respectively, when the addition level of SP reached 15%, due to the inhibition activity of SP against digestive enzymes, as well as the molecular reorganisation of starch. After the in vitro digestion, the bioaccessibility of SP in starch gels increased by a magnitude of 2.58-fold (RS) and 2.98-fold (WS). These results provide evidence of using SP as functional formulations in controlling gel-like foods structure behaviours and modulating the glycaemic response of starchy foods. • The main sea buckthorn phenolics (SP) were syringic acid, gallic acid, and catechin. • SP reduced the peak viscosity and breakdown value of starch significantly (p < 0.05). • IC 50 of ⍺-amylase and ⍺-glucosidase by SP were 0.26 mg/mL and 0.16 mg/mL. • SP interacted with starch via non-covalent H-bonds forming a loose gel structure. • SP facilitated the ordered structure of starch gels with anti-digestive properties. [ABSTRACT FROM AUTHOR]