Effects of electron beam irradiation on physicochemical properties of corn flour and improvement of the gelatinization inhibition

Effect of electron beam irradiation pretreatment and different fatty acid types on the formation, structural characteristics and functional properties of starch-lipid complexes

The effects of different electron beam irradiation doses (2, 4, 8 KGy) and various types of fatty acids (lauric acid, stearic acid, and oleic acid) on the formation, structure, physicochemical properties, and digestibility of starch-lipid complex were investigated. The complexing index of the complexes was higher than 85 %, indicating that the three fatty acids could easily form complexes with starch. With the increase of electron beam irradiation dose, the complexing index increased first and then decreased. The highest complexing index was lauric acid (97.12 %), stearic acid (96.80 %), and oleic acid (97.51 %) at 2 KGy radiation dose, respectively. Moreover, the microstructure, crystal structure, thermal stability, rheological properties, and starch solubility were analyzed. In vitro digestibility tests showed that adding fatty acids could reduce the content of hydrolyzed starch, among which the resistant starch content of the starch-oleic acid complex was the highest (54.26 %). The lower dose of electron beam irradiation could decrease the digestibility of starch and increase the content of resistant starch.

Investigation of the role of sodium chloride on wheat starch multi-structure, physicochemical and digestibility properties during X-ray irradiation

In this paper, different NaCl content was added to wheat starch and then subjected to X-ray irradiation to investigate the effect of salt on starch modification by irradiation. The results showed that the degradation of wheat starch intensified with the increase in irradiation dose. When irradiated at the same dose, wheat starch with sodium chloride produced shorter chains, lower molecular weight and amylose content, and higher crystallinity, solubility, and resistant starch than wheat starch without sodium chloride. The energy generated by X-rays dissociating sodium chloride caused damage to the glycoside bonds of the starch molecule. With a further increase in the mass fraction of NaCl, the hydrogen bonds of the starch molecules were broken, and the double helix structure was depolymerized, which exacerbated the extent of irradiation-modified wheat starch. At the same time, starch molecules will be rearranged to form a more stable structure.

Improvement of sorghum-wheat blended flours by E-beam irradiation: Physicochemical properties, rheological behavior, microstructure, and quality properties

To enhance the processing suitability of blended flours, this study used 4 kGy E-beam irradiated (EBI) sorghum flour in different ratios blended with wheat flour and further verified the improvement mechanism of the processed products under the optimal ratios. The results suggested that the EBI can mitigate the deterioration of the blend flour farinograph properties while enhancing the gas release during dough fermentation. Under the same addition ratio, the irradiated blend flours showed higher expansion height, gas release, cavitation time, and gas retention coefficient than the control flours. Also, irradiated blend flours retained a gluten network at a higher addition rate (20 %). Moreover, the irradiated blend flours were optimized at 10 % as its pasting and thermal properties were improved. Notably, this ameliorating effect promotes a decrease in hardness and chewiness and an increase in cohesion of the bread cores, presenting better textural attributes and delaying the aging rate during storage. The findings are instructive for applying EBI technology in the manufacture and quality improvement of mixed grain breads and open a new research avenue for processing sorghum staple foods.

Understanding the improvement of sorghum starch acid hydrolysis modification by E-beam irradiation: A supramolecular structure perspective

To investigate the effect of E-beam irradiation (EBI) on acid-hydrolyzed starch, sorghum starch was pretreated with EBI (2, 4, and 8 kGy) and further hydrolyzed using hydrochloric acid (1 % and 6 % concentrations) in this study. EBI intensified acid hydrolysis corrosion on starch granule surfaces without inducing changes in the growth ring, FT-IR spectra, and crystal type (A-type). Also, EBI promoted starch degradation by acid hydrolysis, as evidenced by the R1047/1022 loss (1.071 to 1.027), the molecular weight decrease, and the chain length distribution shift (toward short A-chain). Moreover, this synergistic modification induced a starch enthalpy decrease (only 9.49 J/g) and crystallinity reduction (29.87 %), while solubility increase (34.27 %) and swelling power inhibition (only 7.65 g/g) were observed. Notably, starch digestibility was improved after synergistic modification. The obtained results broaden the processing depth of EBI in modified starch and highlight the promising application of acidolysis sorghum starch as a potential industrial starch.

Influence of 10 MeV electron beam irradiation on the lipid stability of oat and barley during storage

This study investigated the effect of electron beam irradiation (EBI) on the lipid stability of oat and barley during long-term storage. Results showed that the initial free fatty acid content in oat was higher than that in barley. This may mean that lipid hydrolysis started under the function of lipase when oat and barley were milled into flours. Both storage and EBI factors influenced lipid-degrading enzyme activity and promoted lipid oxidation in oat and barley. However, it seemed that storage had higher impacts because the DPPH scavenging activity decreased greatly, and the contents of both malondialdehyde and volatile lipid oxidation products increased in all samples. Thus, the antioxidant capacity and level of lipid oxidation after EBI treatment should be considered when producing oat and barley foods. Overall, this study shows the high potential of EBI for use as a non-thermal technique in stabilising the storage quality of oat and barley.

Chroogomphus rutilus Regulates Bone Metabolism to Prevent Periodontal Bone Loss during Orthodontic Tooth Movement in Osteoporotic Rats

Osteoporosis (OP) leads to the acceleration of tooth movement and aggravation of periodontal bone loss during orthodontic treatment. Chroogomphus rutilus (CR) is abundant in nutrients and demonstrates remarkable antioxidant and anti-inflammatory properties. In the present study, the components of CR, including 35.00% total sugar, 0.69% reducing sugar, 14.40% crude protein, 7.30% total ash, 6.10% crude fat, 0.51% total flavonoids, 1.94% total triterpenoids, 0.32% total sterol, 1.30% total saponins, 1.69% total alkaloids, and 1.02% total phenol, were first systematically examined, followed by an investigation into its regulatory effects on bone metabolism in order to mitigate bone loss during orthodontic tooth movement in osteoporotic rats. The results of the imaging tests revealed that CR treatment reduced periodontal bone loss and normalized tooth movement in the OP. In conjunction with analyses of intestinal flora and metabolomics, CR enhances the prevalence of anti-inflammatory genera while reducing the production of inflammatory metabolites. Meanwhile, CR reduced the levels of periodontal inflammatory factors, including TNF-α, IL-1β, and IL-6, by activating Wnt/β-catenin signaling, and promoted periodontal bone formation. These findings imply that CR is a potent supplementary therapy for controlling periodontal bone remodeling in patients with OP undergoing orthodontic treatment.

Insight into how E-beam pretreatment promotes sodium hypochlorite oxidation for structure-property improvement of cassava starch: A molecular-level modulation mechanism

To investigate the role of E-beam treatment on the structure-properties of oxidized starch, this study investigated the influence of E-beam (1, 3, 6 kGy) pretreatment combined with NaClO oxidation (1% and 3%) on the multi-scale structural, physicochemical, and digestive properties of cassava starch. Results showed that E-beam treatment did not affect the starch surface, but the oxidative modification increased granule surface roughness. Also, the synergistic modification preserved starch growth rings, FT-IR patterns and crystal types. Further investigations revealed that E-beam induced starch molecular degradation, leading to decreased molecular weight, depolymerization of long chains, and a loss of short-range order. Moreover, oxidation treatment exacerbated the disruption in starch molecular structure, as evidenced by crystallinity loss, viscosity, and enthalpy reduction. Notably, E-beam induces starch yellowing; however, oxidative modification increases starch whiteness. Additionally, the synergistic modification improved native starch's lower solubility and enhanced the resistant starch content. Results suggest that E-beam pretreatment can enhance oxidative modification by promoting the exposure of active sites of starch molecules without destroying starch structure and can be considered an advanced, green, and efficient pretreatment for modified starch in the future.

Effect of electron beam irradiation on granular cold-water swelling chestnut starch: Improvement of cold-water solubility, multiscale structure, and rheological properties

In this study, granular cold-water swelling (GCWS) starch was prepared from chestnut starch by ethanol-alkali method, after which it was further modified by electron beam irradiation (EBI) technique to investigate the effect of EBI on GCWS chestnut starch. It was shown that the alcohol-alkali treatment disrupted the starch double helix structure and the starch crystalline form had been changed from "C" to "V" type. On this basis, EBI continued to act on the disrupted starch chains and further cleaved the long chains into short chains, which significantly improved the solubility of starch to 90.08 % in cold water at a 24 kGy irradiation dose. Therefore, this study can broaden the application scope of starch and provide new ideas for GCWS starch applications in food and water-soluble pharmaceutical industries.

Ionizing and nonionizing radiations can change physicochemical, technofunctional, and nutritional attributes of starch

Challenges for the food/non-food applications of starch mostly arise from its low stability against severe processing conditions (i.e. elevated temperatures, pH variations, intense shear forces), inordinate retrogradability, as well as restricted applicability. These drawbacks have been addressed through the modification of starch. The escalating awareness of individuals toward the presumptive side effects of chemical modification approaches has engrossed the attention of scientists to the development of physical modification procedures. In this regard, starch treatment via ionizing (i.e. gamma, electron beam, and X-rays) and non-ionizing (microwave, radiofrequency, infrared, ultraviolet) radiations has been introduced as a potent physical strategy offering new outstanding attributes to the modified product. Ionizing radiations, through dose-dependent pathways, are able to provoke depolymerization or cross-linking/grafting reactions to the starch medium. While non-ionizing radiations could modify the starch attributes by changing the morphology/architecture of granules and inducing reorientation/rearrangement in the molecular order of starch amorphous/crystalline fractions.

Influence of pre- or post-electron beam irradiation on heat-moisture treated maize starch for multiscale structure, physicochemical properties and digestibility

Electron beam irradiation (EBI) as a green technological method for starch modification can generate starch-based materials with new functions. This study modified maize starch by heat-moisture treatment (HMT) for 1 h and 3 h, and EBI with various intensities (5 kGy and 10 kGy), and their effects of treatment sequence on the multiscale structure, physicochemical properties and in vitro digestibility were investigated. EBI or HMT alone did not change the granule morphology and crystalline type, but reduced the crystallinity and molecular weight and increased the resistant starch content. HMT alone had no significant effect on the solubility of starch, while EBI led to a considerable increase in the solubility of maize starch. The combined treatment of EBI and HMT aggravated apparent viscosity reduction, and the HMT starch pretreated with EBI had a smaller molecular weight and lower viscosity. In contrast, post-EBI samples had higher solubility and RS content. Primarily, it has excellent potential for producing low-viscosity and high-solubility starch foods.

The role and mechanism of electron beam irradiation in glutaric anhydride esterified proso millet starch: Multi-scale structure and physicochemical properties

To investigate the effect of electron beam irradiation (EBI) pretreatment on the multiscale structure and physicochemical properties of esterified starch, this study used EBI pretreatment to prepare glutaric anhydride (GA) esterified proso millet starch. GA starch did not show the corresponding distinct thermodynamics peaks. However, it had a high pasting viscosity and transparency (57.46-74.25 %). EBI pretreatment increased the degree of glutaric acid esterification (0.0284-0.0560) and changed its structure and physicochemical properties. EBI pretreatment disrupted its short-range ordering structure, reducing the crystallinity, molecular weight and pasting viscosity of glutaric acid esterified starch. Moreover, it produced more short chains and increased the transparency (84.28-93.11 %) of glutaric acid esterified starch. This study could offer a rationale for using EBI pretreatment technology to maximize the functional properties of GA modified starch and enlarge its implementation in modified starch.

Effects of electron beam irradiation treatment on the structural and functional properties of okara insoluble dietary fiber

BACKGROUND

Insoluble dietary fiber (IDF) has beneficial physiological effects, such as the promoting of intestinal peristalsis, the improving of intestinal flora, and the absorbing of some harmful substances. Okara, a byproduct of soybean processing, is a potential source of IDF. But the larger particle size and poor water solubility of okara IDF have adverse effects on sensory properties and functional characteristics. Therefore, we used an emerging type of physical method is electron beam irradiation (EBI) to modify okara, and investigated that the effects of EBI doses on the structure and functional properties of okara IDF.

RESULTS

It was found that the electron beam treatment damaged the crystalline structure of IDF. Observation of the surface of EBI-treated IDF revealed a loose and porous morphology rather than the typical smooth structure. At a dose of 6 kGy, a smallest particle size and largest specific surface area of IDF was obtained, and these factors increased the apparent viscosity of an IDF dispersion. The water holding capacity, swelling capacity and the oil holding capacity upon irradiation at 6 kGy increased 74.13%, 84.76% and 41.62%, respectively. In addition, the capacity for adsorption of cholesterol, sodium cholate, glucose and nitrite ion were improved after electron beam treatment.

CONCLUSION

The modified okara IDF showed improved particle sizes and hydration properties, and these changes correlated with an improvement to the rough taste of IDF and improvements to the texture and storage period upon supplementation into food. © 2022 Society of Chemical Industry.

Characteristics of germinated corn flour and influence of germination on cookie properties

The aim of this study was to investigate the effect of germination on the physicochemical, structure, pasting, and morphological properties of corn. Germination improved total phenolic content (TPC) and antioxidant capacity (AC). Scanning electron micrographs (SEM) of flour showed that some starch granule was destroyed with germination. In the same way, pasting values decreased due to changes in the starch granule. FT-IR (Fourier Transform Infrared) spectra confirmed that germination leads to changes in the chemical structure. The XRD (X-ray diffractometer) analysis showed that patterns did not change with germination. In addition, raw and germinated corn flour were used in gluten-free cookie preparation. The cookie dough was evaluated for stickiness. The physical, textural, colour, TPC, and AC of cookie samples were determined. Gluten-free cookies prepared with germinated flour exhibited significantly higher AC due to increase in TPC. Germination could be used to enhance functional properties of corn.

Development of Novel Gluten-Free Sausage Based on Chickpea, Corn Flour, and HPMC

The present work was carried out to study the effectiveness of substitution of wheat flour with different levels of chickpea flour, corn flour, and hydroxypropyl methylcellulose (HPMC) for the production of gluten-free sausages. The prepared sausages were subjected to physicochemical, color, texture, thermal, and sensory analyses 24 h after production. Proximate chemical composition indicated that the protein content was raised by the addition of chickpea flour. The result of thermal analysis indicated that the addition of chickpea flour increased To, Tp, Tf, and ΔH and decreased ∆W₁. Textural properties revealed that hardness was higher in samples containing chickpea flour and adhesiveness, chewiness, and gumminess were lower in samples with chickpea flour and corn flour. Sensorial properties showed that there were no significant differences between samples except the sample containing 6% chickpea flour. Based on the obtained results, it seems that the sample containing 4% corn flour, 6% chickpea flour, and 0.3% HPMC had the best formulation.

Effects of irradiation treatment on protein structure and digestion characteristics of seed-watermelon (Citrullus lanatus var.) kernel protein

This study examined the effects of different doses of irradiation treatments on protein structure and digestion characteristic of seed-watermelon seed kernel protein. The results showed that, the molecular structure of seed-watermelon kernel protein was unfolded after the irradiation treatment, the content of β-sheet structure in the secondary structure was decreased, while the content of random coil structure increased. The average particle size of the protein increased, and the hydrophobic group buried in the β-sheet structure was exposed hence the surface hydrophobicity increased. Besides, the surface morphology of seed-watermelon protein changed from smooth and flat to coarse and concave, the specific surface area in contact with the aqueous medium increased and its solubility increased, the distribution of peptides in the digesta became wider, and the small molecular weight peptides gradually increased.

Influences of Electron Beam Irradiation on the Physical and Chemical Properties of Zearalenone- and Ochratoxin A-Contaminated Corn and In Vivo Toxicity Assessment

Electron beam irradiation (EBI) has high energy, no induced radioactivity, and strong degradation capacity toward mycotoxins, such as zearalenone (ZEN) and ochratoxin A (OTA). In this study, we determined EBI’s influence on the physical and chemical properties of corn contaminated with ZEN and OTA. Moreover, the toxicity of corn after EBI was assessed through a mouse experiment. Amylose content and starch crystallinity in corn decreased significantly (p < 0.05) at an irradiation dose higher than 20 kGy. Scanning electron microscopy results revealed that the starch particles of corn began to be crushed at 10 kGy. Essential and total amino acid contents in corn decreased significantly with increasing irradiation dose of EBI (p < 0.05). Feeding EBI-treated corn fodders to mice could significantly improve blood biochemical indexes. The EBI-treated group was not significantly different from the normal corn group and did not display histopathological changes of the liver. EBI treatment can influence the quality of corn to some extent and effectively lower the toxicity of ZEN and OTA in contaminated corn. The results provide a theoretical and practical basis for the processing of EBI-treated corn and its safety.

Effects of electron beam irradiation on the properties of waxy maize starch and its films

Waxy maize starch was irradiated under different doses of radiation (2-30 kGy), and starch physicochemical properties were analysed. Films were subsequently produced from native and irradiated waxy maize starches and their properties were tested. The starch molecular weight markedly decreased with increasing irradiation dose. And the branch chain length, melting temperature, melting enthalpy, and relative crystallinity decreased slightly, especially at an irradiation dose below 15 kGy. This indicated that more α-1,6-glucosidic bonds than α-1,4-glucosidic bonds were cleaved by a low dose of irradiation; hence, more linear chains were released. Films prepared from 10 kGy irradiated waxy maize starch displayed enhanced mechanical properties and increased solubility, owing to a moderate increase in linear starch chains and a decrease in starch molecular weight, respectively. The resulting rapidly-dissolvable films from irradiated waxy maize starch have potential for use in instant food packaging.

Characterization of the physical properties of electron-beam-irradiated white rice and starch during short-term storage

Electron-beam irradiation (EBI) is a cold sterilization technology used in the irradiation processing of food, including rice. Herein, the effects of EBI on the swelling power, color, pasting, and sensory properties of white rice after short-term storage were analyzed. Samples were electron-beam irradiated at 0, 2, 4, 6, or 8 kGy and stored at 25 °C or 37 °C for up to 75 days. Results showed that swelling power and major pasting viscosities (including peak, breakdown, and setback viscosities) at both storage temperatures decreased with increased irradiation dose. Negative correlations were also observed between the major viscosities of pasting properties and irradiation dose at both storage temperatures. During sensory evaluation, extremely low scores for rice hardness, appearance, taste, and overall acceptability were obtained for rice subjected to high EBI dose (>4 kGy). However, rice stored at 37 °C showed lower performance than rice at 25 °C in terms of the abovementioned parameters. By contrast, the sensory properties at irradiation doses between 2 and 4 kGy were better than those of the control group at both storage temperatures. All these findings indicated the potential of low-dose (<4 kGy) EBI as pretreatment for improving the quality of white rice during storage.

Effect of Food Structure, Water Activity, and Long-Term Storage on X-Ray Irradiation for Inactivating Salmonella Enteritidis PT30 in Low-Moisture Foods

Recent outbreaks and recalls of low-moisture foods contaminated with Salmonella have been recognized as a major public health risk that demands the development of new Salmonella mitigation strategies and technologies. This study aimed to assess the efficacy of X-ray irradiation for inactivating Salmonella on or in almonds (kernels, meal, butter), dates (whole fruit, paste), and wheat (kernels, flour) at various water activities (a_w) and storage periods. The raw materials were inoculated with Salmonella Enteritidis PT30, conditioned to 0.25, 0.45, and 0.65 a_w in a humidity-controlled chamber, processed to various fabricated products, and reconditioned to the desired a_w before treatment. In a storage study, inoculated almond kernels were stored in sealed tin cans for 7, 15, 27, and 103 weeks, irradiated with X ray (0.5 to 11 kGy, targeting up to a ∼2.5-log reduction) at the end of each storage period, and plated for Salmonella survivors to determine the efficacy of irradiation in terms of D₁₀-value (dose required to reduce 90% of the population). Salmonella was least resistant (D₁₀-value = 0.378 kGy) on the surface of almond kernels at 0.25 a_w and most resistant (D₁₀-value = 2.34 kGy) on the surface of dates at 0.45 a_w. The Salmonella D₁₀-value was 61% lower in date paste than on whole date fruit. Storage of almonds generally had no effect on the irradiation resistance of Salmonella over 103 weeks. Overall, these results indicate that product structure (whole, meals, powder, or paste), water activity (0.25 to 0.65 a_w), and storage period (0 to 103 weeks) should be considered when determining the efficacy of X-ray irradiation for inactivating Salmonella in various low-water-activity foods.

The Antidiabetic and Antinephritic Activities of Auricularia cornea (An Albino Mutant Strain) via Modulation of Oxidative Stress in the db/db Mice

This study first systematically analyzed the constituents of an albino mutant strain of Auricularia cornea (AU). After 8 weeks of continuous treatment with metformin (Met) (0.1 g/kg) and AU (0.1 and 0.4 g/kg), db/db mice showed hypoglycemic functioning, indicated by reduced bodyweight, food intake, plasma glucose, serum levels of glycated hemoglobin A1c and glucagon, hepatic levels of phosphoenolpyruvate carboxykinase and lucose-6-phosphatasem, and increased serum levels of insulin. The effect of hypolipidemic functions were indicated by suppressed levels of total cholesterol and triglyceride, and enhanced levels of hepatic glycogen and high-density lipoprotein cholesterol. The renal protective effect of AU was confirmed by the protection in renal structures and the regulation of potential indicators of nephropathy. The anti-oxidative and anti-inflammatory effects of AU were verified by a cytokine array combined with an enzyme-linked immunosorbent assay. AU decreased the expression of protein kinase C α and β2 and phosphor-nuclear factor-κB, and enhanced the expression of catalase, nuclear respiratory factor 2 (Nrf2), manganese superoxide dismutase 2, heme oxygenase-1 and−2, heat shock protein 27 (HSP27), HSP60, and HSP70 in the kidneys of db/db mice. The results confirmed that AU's anti-diabetic and anti-nephritic effects are related to its modulation on oxidative stress.

Comparative Analyses for Gluten-Free Biscuits from Mixture Oat and Corn

Gluten-free products are necessary for the people suffering from celiac disease or having a sensibility for products containing gluten. The aim of this study was to prepare and evaluate gluten free biscuits made from a mixture of flours (50% corn flour and 50% oat flour) with various fats (palm fat, coconut oil) and sweeteners (sugar, stevioside with erythritol). Sample biscuits were made and then analyzed to find out the moisture, water activity, braking point, specific volume and sensory evaluation. All samples had the moisture close to 5-6%. Water activity ranged from 0.49 to 0.71. The breaking point was higher for sample prepared with palm fat and sugar (0.43). This sample was accepted by panellist better than others samples of biscuits.

The Antidiabetic and Antinephritic Activities of Tuber melanosporum via Modulation of Nrf2-Mediated Oxidative Stress in the db/db Mouse

Tuber melanosporum (TM), a valuable edible fungus, contains 19 types of fatty acid, 17 types of amino acid, 6 vitamins, and 7 minerals. The antidiabetic and antinephritic effects of TM and the underlying mechanisms related to oxidative stress were investigated in db/db mice. Eight-week oral administration of metformin (Met) at 0.1 g/kg and TM at doses of 0.2 and 0.4 g/kg decreased body weight, plasma glucose, serum levels of glycated hemoglobin, triglyceride, and total cholesterol and increased serum levels of high-density lipoprotein cholesterol in the mice, suggesting hypoglycemic and hypolipidemic effects. TM promoted glucose metabolism by increasing the levels of pyruvate kinase and hepatic glycogen. It also regulated the levels of inflammatory factors and oxidative enzymes in serum and/or the kidneys of the mice. Additionally, TM increased the expression of nuclear respiratory factor 2 (Nrf2), catalase, heme oxygenase 1, heme oxygenase 2, and manganese superoxide dismutase 2 and decreased the expression of protein kinase C alpha, phosphor-janus kinase 2, phosphor-signal transducer and activator of transcription 3, and phosphor-nuclear factor-κB in the kidneys. The results of this study reveal the antidiabetic and antidiabetic nephritic properties of TM via modulating oxidative stress and inflammation-related cytokines through improving the Nrf2 signaling pathway.