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This study presents the effects of dry heat (DH) assisted by pre-and post-electron beam (EB) treatment on buckwheat starch's multiscale structural, physicochemical, and digestive properties. The granule integrity and crystal shape were not affected by the investigated treatments. However, DH and EB treatments decreased amylose content, crystallinity, molecular weight, swelling power, thermal transition temperatures and gelatinization enthalpy while increasing solubility and the content of A chain, B1 chain, and resistant starch. EB application to DH starch promoted subsequent structural changes and enhanced starch properties compared to samples DH-processed alone. In addition, EB-induced starch chain depolymerization and structural rearrangement had sequential effects. EB pre-treatment reduced DH starch's amylose content, molecular weight, and swelling power while enhancing the content of A- chain, rapidly digestible starch, and resistant starch compared with EB post-treatment. This innovative study provides a theoretical basis for the potential applicability of EB irradiation in modifying the properties of DH starch.

Exploration and synthesis of degradable plastics can alleviate and avoid environmental pollution induced by petroleum-based plastics. In this study, a konjac glucomannan (KGM)/zein/PVA ternary blend plastic was successfully prepared by casting. The results showed that, despite the presence of particle aggregation from incompatible components in blend plastic, the addition of KGM and zein improved its compatibility which is consistent with the formation of continuous dark regions and the reduction of roughness average (Ra) results in the AFM characterization. Also, XRD and FT-IR results indicated that the addition of KGM and zein disrupted the molecular and crystalline structure of PVA, induced stretching vibration of alcohol and hydroxyl groups, and crystallinity reduction. In addition, KGM deacetylation (d-KGM) reduced the intramolecular hydroxyl groups, reduced the water absorption and water vapor transmission rate of the blend plastics, and increased the crystallization temperature (Tc) and melting temperature (Tm). Furthermore, the blended plastics exhibited the best tensile strength (TS), elongation at break (E), and elastic modulus (EM) when the proportion of KGM to zein was 9:1. Notably, the blended plastic with KGM and zein added displayed more pores and cracks after soil burial, implying that the lack of degradability of pure PVA plastic was improved.

Potato tubers are susceptible to wounding during post-harvest processes, leading to quality decline, perishability and large economic losses. In this study, the potato cultivar, ‘Longshu No.7′, was foliar-sprayed with 3% chitosan (w/v) three times during the pre-harvest period after flowering to evaluate the effect of foliar spraying with chitosan on suberization processing in the wounds of harvested potato tubers. Our results demonstrated that foliar sprayed with chitosan significantly reduced wound-induced fresh weight loss and dry rot disease index by 37.34% and 41.60% on day 28 after wounding, respectively. Foliar sprayed with chitosan accelerated the deposition of suberin polyphenolic and lignin at the wound sites of potato tubers with the formation of thicker cell layers. This occurred with increased localized activities of key enzymes in the suberin polyphenolic and lignin pathways, including phenylalanine ammonia lyase, 4-coumaryl-coenzyme A ligase, cinnamyl alcohol dehydrogenase and peroxidase (33.90–64.32%), as well as the contents of cinnamic acid, sinapic acid, flavonoids, lignins and total phenolics (19.70–23.46%) in the wounded sites of potato tubers on day 7 after wounding. Our results indicated that foliar application of chitosan accelerated wound-induced suberization of potato tubers and could mitigate post-harvest product damages.

The ball milling (BM), electron beam irradiation (EBI), the combination of them, and their effects on granules morphology, multiscale structure, physicochemical properties, and digestibility of corn starch are discussed in this paper. Both BM and EBI reduced crystallinity, amylopectin molecular weight (Mw), pasting viscosities, gelatinization temperatures, and resistant starch (RS) content, but increased amylose Mw and rapidly digestible starch content. BM treatment damages the starch granules, which makes them easier to attack by free radicals of subsequent EBI treatment. In addition, the BM pretreatment promoted starch chain depolymerization and crystalline structure destruction, reinforcing the joint effect of subsequent EBI treatment. Therefore, BM-EBI-starches exhibited lessened crystallinity, amylopectin Mw, pasting viscosities, gelatinization temperatures, enthalpy and RS content than native and single-treated starch. This paper would like to reference potential industrial applications of BM and EBI technologies to modify starch.

The study used electron beam (EB) irradiation pretreatment to prepare acetylated (AC) naked barley starch. EB pretreatment enhanced the degree of substitution in acetylation from 0.027 to 0.109 %. The starch granules treated with EB and AC had a rough surface but maintained integrity. EB depolymerized the starch structure, providing opportunities for molecular rearrangement, thereby increasing the efficiency in the subsequent acetylation process. Therefore, EB pretreatment decreased AC starch amylose content (27.82 to 21.61 %), amylopectin molecular weight, relative crystallinity (31.04 to 26.23 %), short-range order, and increased amylose molecular weight comparing EB or AC-treated alone. These structural changes improve the properties of starch; thus, EB pretreatment reduced the thermal transition temperature, gelatinization enthalpy, pasting parameters, rapidly-digestible starch content (67.09-51.74 %), solubility, and improved content of slowly-digestible starch (23.82-36.65 %) and resistant starch (9.09-11.62 %). EB pretreatment can enhance efficiency and improve the structure and performance of acetylated modified starch.

The effects of continuous heat-moisture treatment (CHM) and repeated heat-moisture treatment (RHM) on multi-scale structure, physicochemical and digestibility properties of wheat A- and B-starch were investigated and compared. Both A- and B-starch granules maintained integrity after repeated and continuous modification. Changes in starch molecules induced the diversification of crystal structure and physicochemical properties. Crystal type of CHM and RHM starches maintained the original A-type while the crystallinity decreased after treatmnt. For wheat A-starch, the RS and RDS contents of RHM starches were obviously lower than native ones while the SDS content increased. Meanwhile, the RDS and SDS contents of treated B-starch were significantly higher than native ones but the RS content was lower. At the same conditions, B-starches exhibited a lower relative crystallinity, lower viscosity parameters, lower To, Tc, Tp and ΔH values than A-starches. In general, the repeated heat-moisture treated samples obtained superior characteristics than continuous treated ones, and the results of A- and B-starch varied greatly.

The poor water solubility and stability of lutein limit its application in industry. Microencapsulation technology is an excellent strategy to solve these problems. This study used citric acid esterified potato starch and whey protein as an emulsifier to prepare oil-in-water lutein emulsion, and microcapsules were constructed by spray drying technology. The effects of different component proportions on microcapsules' microstructure, physical and chemical properties, and storage stability were analyzed. Citrate esterified potato starch had good emulsifying properties, and when compounded with whey protein, the encapsulation efficiency (EE) of microcapsules increased, and the embedding effect of lutein improved. After microencapsulation, the solubility of lutein increased significantly, reaching over 49.71 %, and gradually raised with more whey protein content. Furthermore, the high proportion of whey protein helped improve microcapsules' EE and thermal properties, with the maximum EE reaching 89.36 %. The glass transition temperatures of microcapsules were all higher than room temperature, which indicated that they keep a stable state under general storage conditions. The experimental results of this study may provide a reference for applying lutein in food and other fields.

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

In this study, proso millet starch was isolated and subjected to treatment with ultra-high pressure (UHP), cold plasma (CP), or their combination to modify its functional properties. The changes in structural, physicochemical, and digestive properties of proso millet starch after these treatments were investigated. The proso millet native starch granules showed irregular and polygonal shapes with a smooth surface. Treatments with CP or UHP at low pressures did not change the morphological properties or crystalline structure type of proso millet starch granules, while the treatment with UHP at 600 MPa and CP resulted in a complete gelatinization of starch. Also, UHP treatment at high pressure, followed by CP treatment, destroyed the partial crystalline region and reduced the short-range order of proso millet starch. Besides, a combination of UHP and CP treatment promoted the depolymerization of long chains in proso millet starch. Moreover, the combined treatments could enhance the resistance to high temperature and shearing and improve the pasting stability of starch. Furthermore, the combined treatment could increase the slowly digestible starch content. Therefore, the combination of UHP and CP treatment can be suggested for modifying the functional properties of proso millet starch and promoting its industrial applications.

As a green and safe physical technology, irradiation is increasingly used to improve starch properties. In the study, oat starch was pre-gelatinized at 70 °C followed by spray drying. Subsequently, the spray-dried starch (SDS) was exposed to electron beam (e-beam) irradiation at different doses to obtain new pre-gelatinized starch. Spray drying caused a decrement in the ratio of long B3 chains and the molecular weight of starch. Spray-dried starch (SDS) slightly increased solubility and swelling power than native starch. When SDS was subjected to e-beam irradiation, its solubility and swelling power increased dramatically, but the pasting viscosities, gelatinization temperatures, apparent viscosity, storage modulus (G') and lost modulus (G″) reduced. The depolymerization of starch molecules and the breakage of amylopectin chains might be responsible for changing the physicochemical properties of e-beam irradiated starch. These results showed that spray drying combined with e-beam irradiation would potentially produce new pre-gelatinized starch.

To optimize the properties of native potato starch and to broaden its application in the food field, it was treated by electron beam irradiation (EBI) with different irradiation doses (6, 12, and 24 kGy) and frequencies (1, 2, 4, and 8 times), and the effects on the multi-scale structure, physicochemical properties, and in vitro digestibility were investigated. The results indicate that the increased dose aggravates starch degradation, generating more short chains and fragments, and reducing molecular weight, viscosity, and swelling power. Also, the higher dose facilitated the relative crystallinity, enhancing the ΔH and improving the RS content of potato starch. Furthermore, the repeated irradiation exhibited a cumulative dose effect: the short-range order, molecular weight, solubility, and swelling power improved after multiple irradiations. In addition, irradiation doses and frequencies neither destroyed starch's surface nor changed the polarized cross and growth ring. Also, all irradiated starch preserved starch's FT-IR spectrum and crystalline type. Moreover, multiple low-dose irradiations can not only improve the starch properties, but also achieve energy-saving purposes. Thus, as a rapid, green, non-thermal modification technology, EBI can impart low molecular weight, low viscosity and high solubility processing properties to starch, and improve its RS content without destroying the starch granular appearance.

This study evaluated drying characteristics, structure and essential oil chemical composition, and biological activity of A. galanga by hot air drying (HAD), vacuum drying (VD), freeze drying (FD). The results showed that HAD had the shortest drying time while FD could better maintain the microstructure and showed a higher essential oil yield than HAD and VD. In addition, E-nose, HS-GC-IMS and HS-SPME-GC-MS could effectively distinguish the essential oil chemical composition of the four samples because different drying methods induced the changes in the profile and content of the compounds. HS-SPME-GC-MS detected 43 compounds, of which alcohols, alkenes, and esters were the main substances in fresh and dry samples. In comparison, HS-SPME-GC-IMS detected 80 compounds, including alcohols, aldehydes, ketones, esters, alkenes. Overall, the FD samples showed more outstanding advantages by evaluating antioxidant properties and antibacterial activities. FD was more suitable for A. galanga drying as it maintains appearance and biological activity.

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

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

This study aimed to evaluate the effects of super-chilled storage (-1.3 °C) combined with starch film packaging containing different contents of sea buckthorn pomace extract (SSF, 0, 1, 2, and 3%, w/w) on the quality of chilled beef. The release kinetics, microstructure, and mechanical properties of the film were also measured to investigate its suitability for super-chilled storage. The results of the meat quality assessment showed that the L*, a*, and sensory evaluation values of the SSF-3% samples were significantly higher (P 0.05), and the pH, b*, thiobarbituric acid reactive substance (TBARS), total volatile basic nitrogen (TVB-N), and total viable count (TCA) were significantly lower (P 0.05) than the SSF-0%. The release of SBP from the SSF film was controlled by diffusion. Furthermore, SSF-3% was found to have a compact microstructure and good mechanical properties at the end of the super-chilled storage. The results demonstrated that SSF is an effective packaging material for beef at super-chilling temperatures.

The effect of dry heat (DH, 130 °C, 1, 3 and 9 h), cold plasma (CP, 40 V, 1, 5 and 10 min) and their combination (D-P) treatment on the structure, physicochemical and digestive properties of red adzuki bean starch were studied. The results showed that DH or CP had slight change in morphology while diffraction pattern of starch was remained. With the extension of treated time of DH and CP, the amylose content, crystallinity, molecular weight, short-range order, the long chain of amylopectin, enthalpy value, swelling power, digestibility were reduced, while gelatinization temperatures, the short chain of amylopectin and solubility were increased. The D-P had deeper modification than the single treatment. The combination of dry heat and cold plasma is a simple and green method to improve the starch structure and enhance starch properties and this modified starch could be implemented to tailor starch to the desired food applications.

Effects of repeated annealing treatments (8 cycles, 12 h each) or continuous annealing treatments (12–96 h) at 50 °C on structural, physicochemical, and digestive properties of normal and waxy wheat starches were investigated. Wheat starches retained the original crystalline structure of A-type after annealing. Annealing treatments increased crystallinity, short chain of amylopectin, viscosity, and gelatinization temperatures of starch. However, molecular weight, long chain of amylopectin, solubility, and swelling power of starch decreased after annealing. Additionally, annealing reduced the in vitro digestibility of wheat starches. The changes in properties of starch varied depending on starch type, normal or waxy, and annealing methods, repeated or continuous. The repeated annealing was found to be more effective in modification of normal wheat starch properties. However, continuous annealing efficiently modified properties of the waxy wheat starch. The obtained results may help in choosing appropriate applications of annealed wheat starches in the food industry.

The effects of microwave (MW) treatments for 30 and 90 s or cold plasma (CP) treatments for 2, 6, and 10 min on structural, physicochemical, and digestive properties of rice starch were investigated and compared with the effects of combined MW and CP treatments. Dual modification of starch using combined MW and CP treatments significantly changed starch granules' morphology, and starch showed lower crystallinity, swelling power, and peak viscosity than rice starch with a single modification. However, no significant changes were found in rice starch's crystalline structure and FT-IR spectra pattern after single or combined treatments. Effects of these treatments on the amylopectin branch chain length distribution and molecular weight of rice starch varied considerably depending on treatment type and treatment duration. Moreover, the dually modified rice starch contained more great content of resistant starch. Thus, the synergistic effects between MW and CP had more profound modification than the single treatment. Also, the dual treatment can be used to produce modified starch for industrial applications.

Protein and fat oxidation are important factors that influence the quality of bovine liver. The objectives of this study were to investigate the degree of oxidation changes in bovine livers during 90d at different temperatures (−20°C, −10°C, 0°C, 10°C, and 20°C), and to develop Arrhenius models to predict its degree of oxidation.Carbonyl, thiobarbituric acid (TBA), peroxide value (POV) as oxidation attributes of bovine liver during storage were measured at different time and the changes were kinetically modeled using the Arrhenius equation. The activation energies of carbonyl, (TBA) and (POV) were 27.48, 55.48, and 58.94 KJ/mol, respectively. The determination coefficients (R2) were above 0.97 for all. In addition, volatile compounds in bovine liver and consumer acceptance of bovine liver pate with bovine liver as the final product were also measured. Among the volatile compounds, The content of aldehydes and ketones in bovine livers stored at different temperatures increased significantly (p

Understanding the structural characteristics of starch can help in determining its functional properties and choosing appropriate applications. This work aimed to comprehensively characterize and understand the morphological, crystalline, and molecular structure of the normal and waxy wheat A- and B- starch granules. X-ray diffraction analysis revealed that both normal and waxy wheat A- and B- starch granules have a typical A-type crystalline structure. Additionally, scanning electron microscopy, small-angle X-ray scattering, and Fourier transform infrared spectroscopy analyses showed differences in shape, the thickness of semi-crystalline growth rings, and short-range molecular order of the normal and waxy A- and B- starch granules. The wheat A-starch granules contained lower proportions of A-chains (DP 6–12) and B1- chains (DP 13–24) than those of the wheat B- starch granules. Also, the results revealed that B1-chains (DP 13–24) play an important role in the formation of surface/mass fractal characteristics of starch granules. Furthermore, the atomic force microscopy analysis showed that the normal and waxy wheat A-starch granules are mass fractal, while the normal and waxy wheat B- starch granules are surface fractal.