Effect of infection of potato plants by Potato virus Y (PVY), Potato virus S (PVS), and Potato virus M (PVM) on content and physicochemical properties of tuber starch.

Potato virus Y (PVY), Potato virus S (PVS), and Potato virus M (PVM) infection of potato plants leads to decreased dry matter and starch content in tubers. Starch samples from potato tubers infected with PVY, PVS, and PVM had higher amylose content. Granules of starch isolated from potato tubers infected by PVS exhibit larger granules than starch granules isolated from tubers of healthy plants. In contrast, in the case of PVM and PVY infection, starch granules were significantly smaller in diameter. A decrease in the degree of crystallinity has been observed in all samples of starches obtained from the tubers of infected plants compared to starch isolated from tubers of healthy plants. A slight decrease in gelatinization temperature was noted for starch samples isolated from tubers infected by PVY and PVM, and a slight increase in gelatinization temperature for starch samples isolated from tubers infected by PVS compared to starch isolated from tubers of healthy plants. In all samples of starch obtained from tubers of infected plants, an increase in the value of gelatinization enthalpy was observed. Thus, it can be concluded that damage to potato plants by PVM and PVY leads to a significant decrease in the quality of starch in tubers. At the same time, infection by PVS had practically no considerable effect.

Electron beam irradiation modification of ultra-high pressure treated broad bean starch: Improvement of multi-scale structure and functional properties.

To investigate the synergistic effect of electron beam irradiation (EBI) on the ultra-high pressure (UHP) modification of broad bean starch, various pressures (200, 400, 600 MPa) combined with different irradiation doses (3, 6, 12 kGy) were used to modify the structure-properties of broad bean starch in this study. The results showed that both UHP and EBI induced a reduction of amylopectin molecular weight (Mw) and depolymerization of long chains, caused the loss of short-range ordered structure and imperfection of crystal structure, and improved starch viscosity, solubility and enzyme sensitivity. Furthermore, the applied pressure causes changes in starch granule structure, upon which EBI promotes further degradation and depolymerization of starch by affecting the crystalline and amorphous regions. Hence, appropriate doses of EBI treatment can impart more desirable processing properties to UHP-modified starches, and EBI can be used as a promising way to promote starch modification further.

Multiscale structure-property relationships of oxidized wheat starch prepared assisted with electron beam irradiation.

In this study, two promising eco-friendly modification techniques, electron beam (EB) irradiation and hydrogen peroxide (H2O2) oxidation, were used to prepare oxidized wheat starch. Neither irradiation nor oxidation changed starch granule morphology, crystalline pattern, and Fourier transform infrared spectra pattern. Nevertheless, EB irradiation decreased the crystallinity and the absorbance ratios of 1047/1022 cm-1 (R1047/1022), but oxidized starch exhibited the opposite results. Both irradiation and oxidation treatments reduced the amylopectin molecular weight (Mw), pasting viscosities, and gelatinization temperatures, while increasing the amylose Mw, solubility and paste clarity. Notably, EB irradiation pretreatment dramatically elevated the carboxyl content of oxidized starch. In addition, irradiated-oxidized starches displayed higher solubility, paste clarity, and lower pasting viscosities than single oxidized starches. The main reason was that EB irradiation preferentially attacks the starch granules, degrades the starch molecules, and depolymerizes the starch chains. Therefore, this green method of irradiation-assisted oxidation of starch is promising and may promote the appropriate application of modified wheat starch.

Electron beam irradiation application for improving the multiscale structure and enhancing physicochemical and digestive properties of acetylated naked barley.

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.

Fabrication of biodegradable blend plastic from konjac glucomannan/zein/ PVA and understanding its multi-scale structure and physicochemical properties.

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.

Understanding how electron beam irradiation doses and frequencies modify the multiscale structure, physicochemical properties, and in vitro digestibility of potato 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.

Electron beam irradiation regulates the structure and functionality of ball-milled corn starch: The related mechanism.

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.

Lutein encapsulated in whey protein and citric acid potato starch ester: Construction and characterization of microcapsules.

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.