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Whole flaxseed (flour) as a good source of omega‐3 fatty acid and phytochemicals with excellent nutritional and functional attributes has been used to enrich foods for health promotion and disease prevention. However, several limitations and contemporary challenges still impact the development of whole flaxseed (flour)‐enriched products on the global market, such as naturally occurring antinutritional factors and entrapment of nutrients within food matrix. Whole flaxseed (flour) with different existing forms could variably alter the techno‐functional performance of food matrix, and ultimately affect the edible qualities of fortified food products. The potential interaction mechanism between the subject and object components in fortified products has not been elucidated yet. Hence, in this paper, the physical structure and component changes of flaxseed (flour) by pretreatments coupled with their potential influences on the edible qualities of multiple fortified food products were summarized and analyzed. In addition, several typical food products, including baked, noodle, and dairy products were preferentially selected to investigate the potential influencing mechanisms of flaxseed (flour) on different substrate components. In particular, the altered balance between water absorption of flaxseed protein/gum polysaccharides and the interruption of gluten network, lipid lubrication, lipid–amylose complexes, syneresis, and so forth, were thoroughly elucidated. The overall impact of incorporating whole flaxseed (flour) on the quality and nutritional attributes of fortified food products, coupled with the possible solutions against negative influences are aimed. This paper could provide useful information for expanding the application of whole flaxseed (flour) based on the optimal edible and nutritional properties of fortified food products. [ABSTRACT FROM AUTHOR]

BACKGROUND: The INFOGEST model is a standardized general in vitro digestion study, but it cannot accurately simulate the fatty acid release process of lipids in the stomach and small intestine. In this study, the internationally universal INFOGEST 2019 was used as the basic model and flaxseed oil emulsion was used as the research object. In various improvement models, the effect of fatty acid release rate on the oxidation stability of flaxseed oil was assessed by adding rabbit stomach extract and changing the order of bile salts addition. RESULTS: With the presence of rabbit gastric extract, flaxseed oil emulsion flocculation and coalescence in stomach were reduced, and the absolute value of ζ‐potential increased. Moreover, the release rate of fatty acids in the small intestine increased by 12.14%. The amount of lipid oxidation product (i.e. hexanal) in the gastric and intestinal phases increased by 0.08 ppb. In addition, the fatty acid release rate in the small intestine phase increased by 5.85% and the hexanal content increased by 0.011 ppb in the digestion model of adding bile salts before adjusting the pH in the small intestine phase compared with the model of adjusting the pH first and then adding bile salts. CONCLUSION: The results obtained from this study will contribute to finding the most suitable static digestion model for simulating digestion and oxidation of lipid during lipid gastrointestinal digestion. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Flaxseed is one of the main cultivated economic oil crops in the world, with a global output of ~3.06 million tons. Its residual meal, after oil industrial processing, is rich in protein (35%–40%). However, flaxseed protein is mainly used for feed and its processing efficiency is low. The potential for high‐value utilization of flaxseed protein is far from being excavated. Interface dominated‐colloidal systems, such as emulsions and foams, are widely available and have extensive applications in food products. Flaxseed protein possesses high contents of hydrophobic amino acids and sulfur‐containing amino acids, relatively ordered secondary structures, tunable structural properties, and acceptable interfacial behaviors. These characteristics give it the potential to effectively stabilize food emulsions and foams. By modifications of flaxseed proteins, such as physical treatment and the complexation with polysaccharides and polyphenols, their structural properties and interfacial behaviors can be regulated, therefore, leading to the enhancement of emulsifying and foaming properties. In this review article, the fractionation, composition, and structure of flaxseed protein are detailed summarized. Then, the interfacial behaviors of flaxseed protein and their control approach are highlighted. Additionally, the emulsions and foams stabilized by flaxseed protein‐based amphiphilic systems and their applications in food processing are emphasized. [ABSTRACT FROM AUTHOR]

Summary: There was an extensive interest in food‐grade Pickering emulsions formulated by natural stabilisers owing to the gradual growing demand for pursuing green‐label products. Based on this, the desalted duck egg white nanogels (DEWN) combined with κ‐carrageenan (CAR) (CAR/DEWN) were used as stabilisers to prepare environment‐friendly Pickering emulsions. The DEWN and CAR/DEWN as well as the particles‐stabilised emulsions were all characterised. Compared with the DEWN‐ and CAR‐stabilised emulsions, Pickering emulsions based on CAR/DEWN were investigated to illustrate the long‐term stability according to the results of visual appearance, static multiple light scattering and centrifugation experiments. In addition, CAR/DEWN could prepare stable high internal phase emulsions, which may give a new perspective for nutraceutical or drug encapsulation and delivery. Adding CAR to the DEWN not only increased the apparent viscosity of the emulsions to 122.2% but also enhanced the thixotropic recovery rate to 87.7%. In general, CAR/DEWN as stabilisers significantly promoted the Pickering emulsions' properties, and provided a possibility for the application of Pickering emulsion in foods. [ABSTRACT FROM AUTHOR]

BACKGROUND: The relatively inferior techno‐functionality of flaxseed protein/polysaccharide complexes, especially regarding emulsifying and antioxidant activities, has partially limited their implication in the health food system. The present study aimed to investigate the effects of an atmospheric pressure plasma jet (APPJ) on the physicochemical, structural and selected techno‐functional properties of flaxseed extracts. RESULTS: The results obtained showed that the full‐fat and defatted flaxseed extract solutions (5 mg mL–1) displayed a sustainable decline in pH (−54.06%, −48.80%, P < 0.05) and zeta potential values (−29.42%, −44.28%, P < 0.05), but a gradual increase in particle sizes, as visualised by an optical microscope, during 0–120 s of APPJ treatment. Moreover, the APPJ led to initial decrease but subsequent increase in protein carbonyls and secondary lipid oxidation products, and concurrently changed the spatial conformation and microstructure of flaxseed extracts, as indicated by endogenous fluorescence properties and scanning electron microscopy (SEM). Additionally, the protein subunit remodeling and gum polysaccharides depolymerization were different for full‐fat and defatted flaxseed extracts after 30 s of APPJ exposure. Importantly, the emulsifying and antioxidant activities of defatted flaxseed extract were particularly improved, as assessed by cyro‐SEM and 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging activity following 15–30 s of APPJ treatment, as a result of the changing interactions between protein and gum polysaccharides, as well as the release of specific phenolic compounds. CONCLUSION: APPJ could serve as a promising strategy for tailoring the specific techno‐functionality of flaxseed extracts based on mild structural modification. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The endogenous fortification of antioxidant lipid concomitants in flaxseed was imperative to improve the oxidative stability of α‐linolenic acid (ALA) in flaxseed and flaxseed oil upon processing, storage and gastrointestinal digestion. The comparative effects of acidic electrolyzed water (ACEW) and tap water (TW) on the triglyceride configuration, typical lipid concomitants, and antioxidant properties of flaxseed were conducted during 0–5 days of germination. The results showed that ACEW enhanced the germination rate of flaxseed by 18.25% and simultaneously suppressed the dynamic depletion of ALA by 5.32% when compared with TW (p <.05). The total phenolic acids, lignans, and flavonoids were effectively accumulated in flaxseed following ACEW‐mediated germination with the further increase by 4.82%, 15.48%, and 8.22% in comparison with those induced by TW (p <.05). The total contents of cyclolinopeptides in flaxseed progressively dropped following either ACEW or TW treatment, a slighter decrease by 5.59% for flaxseed treated by ACEW than that by TW. Notably, the maximum accumulation of tocopherols and phytosterols had been early obtained for flaxseed treated with ACEW for 2–3 days due to the de novo synthesis or intermolecular conformational transition (p <.05). Most importantly, ACEW‐mediated germination led to higher increment of the thermal oxidative stability and antioxidant properties of flaxseed and flaxseed oil in comparison to TW. In brief, the initial oxidation temperature increased by 7.09% and 3.06% (p <.05), and the antioxidant activities as evaluated by DPPH, ABTS, and FRAP values raised by 3.86%–28.07% and 4.21%–9.18% (p <.05), respectively. These findings clarify that the germination especailly mediated by ACEW could be an effective method to further optimize the nutritional and functional properties of flaxseed through reconstructing the endogenous antioxidant system. The endogenous fortification of bioactive lipid concomitants in flaxseed was imperative to improve the oxidative stability of α‐linolenic acid in flaxseed and flaxseed oil upon processing, storage, and gastrointestinal digestion. The comparative effects of acidic electrolyzed water (ACEW) and tap water (TW) on the changes in triglyceride configuration, typical lipid concomitants, and antioxidant properties of flaxseed and flaxseed oil were conducted during 5 days of germination. Our findings clarify that the germination especailly mediated by ACEW could be an effective method to further optimize the nutritional and functional properties of flaxseed through reconstructing the endogenous antioxidant system. [ABSTRACT FROM AUTHOR]

Summary: Fungal pretreatment is the most common strategy for improving the conversion of rapeseed meal (RSM) into value‐added microbial products. It was demonstrated that Bacillus amyloliquefaciens CX‐20 could directly use RSM as the sole source of all nutrients except the carbon source for iturin A fermentation with high productivity. However, whether fungal pretreatment has an impact on iturin A production is still unknown. In this study, the effects of fungal pretreatment and direct bio‐utilization of RSM for iturin A fermentation were comparatively analysed through screening suitable fungal species, and evaluating the relationships between iturin A production and the composition of solid fermented RSM and liquid hydrolysates. Three main unconventional adverse effects were identified. (1) Solid‐state fermentation by fungi resulted in a decrease of the total nitrogen for B. amyloliquefaciens CX‐20 growth and metabolism, which caused nitrogen waste from RSM. (2) The released free ammonium nitrogen in liquid hydrolysates by fungal pretreatment led to the reduction of iturin A. (3) The insoluble precipitates of hydrolysates, which were mostly ignored and wasted in previous studies, were found to have beneficial effects on producing iturin A. In conclusion, our study verifies the unconventional adverse effects of fungal pretreatment on iturin A production by B. amyloliquefaciens CX‐20 compared with direct bio‐utilization of RSM. [ABSTRACT FROM AUTHOR]

Canolol is a potential antioxidation ingredient in rapeseed oil. Rapeseed oil with two levels of canolol (528.9 vs. 250.5 mg/kg) was used for stir‐frying different foods (potatoes, tofu, and vegetables). Comprehensive evaluations indicated that the canolol content in high canolol rapeseed oil (HCR) and low canolol rapeseed oil (LCR) after stir‐frying were in the range of 187.8–237.7 and 45.6–96.4 mg/kg, respectively. The degradation rate of total phenol was 58.4% and 80.3% in HCR and LCR, respectively. The loss rates of α‐ and γ‐tocopherol were 24.5% and 47.6%, respectively. Phytosterol concentration decreased by 20% and trans‐fatty acid was not detected in either rapeseed oil. In addition, the peroxide value, anisidine value, and malondialdehyde content in HCR were lower than those in LCR. The oxidative stability index in HCR was longer, showing lower extent of deterioration. Rapeseed oil with high canolol content displayed good oxidation resistance due to significant positive correlation with oxidation induction time (p < .01). [ABSTRACT FROM AUTHOR]

α‐Amylase, an essential biomarker in pancreas related diseases and perform a major role in carbohydrates metabolism. Hence, monitoring the dynamic changes of α‐amylase is crucial for better clinical diagnosis of diseases. However, the existing methods are suffered from low sensitivity, time consumption and indirect assay with aid of tool enzyme or inhibitor of competitive substrates, the rapid and non‐destructive sensing of α‐amylase in biological samples was highly desired. In this work, a very simple tetraphenylethylene motif and γ‐cyclodextrin based supramolecular fluometric sensing system was firstly established. This system has no emission signal in aqueous media for the freely rotation of phenyl rings in the cavity of γ‐cyclodextrin, but the AIE residues can be released in to water after the α‐amylase hydrolysing γ‐cyclodextrin, then turn on the fluorescence. In this system, the detection limit is calculated to be 0.007 U mL−1 in MES buffer with a linear range of 0–0.35 U mL−1, having excellent selectivity to α‐amylase compared to other proteins. At last, our probe can be applied to the quantitative analysis of α‐amylase in human serum, showing potential in point of care testing. How to be a good guest: A supramolecular probe based on the tetraphenylethylene motif and γ‐cyclodextrin host–guest inclusion for α‐amylase recognition was designed and synthesized. The specific cleavage of the 1,4‐glycosidic bonds in cyclodextrin by α‐amylase results in the release of the guest molecule TPESO3Na, a relatively amphiphilic moiety that self‐assembles into a highly fluorescent micelle, thus giving rise to "turn‐on" fluorescent signals. [ABSTRACT FROM AUTHOR]

Background and objectives: The changes in polar metabolites and volatiles in sesame seeds during roasting were analyzed to provide new information for the formation mechanism of sesame oil aroma. Findings: The results showed that the typical sesame aroma components, heterocyclic compounds, increased with the extension of the roasting time and reached 43.78% at 12 min. However, the proportion of aliphatics and terpenoids decreased with the roasting time. In addition, the main polar metabolites in sesame seeds, free amino acids and monosaccharides, continually decreased from 497.14 μg/g and 268.85 μg/g in raw seeds to 144.59 μg/g and 7.52 μg/g in 12‐min roasted seeds, respectively. Conclusions: Based on the changes in specific polar metabolites and volatile compounds, it could be inferred that pyrazines mainly generated through Maillard reaction with Ala and glucose as the possible primary substrates. While S‐heterocycles might be mainly formed through the thermal degradation of proteins and subsequent reactions. Significance and novelty: The results of this study provide important information and new details for the aroma formation process of sesame seeds during roasting and would provide a reference for the study and optimization of sesame roasting and oil extraction processes, as well as the development of sesame seed products. In addition, relevant information can also provide clues for the artificial synthesis of sesame seed aroma components. [ABSTRACT FROM AUTHOR]

Brain insulin resistance, induced by neuroinflammation and oxidative stress, contributes to neurodegeneration, that is, processes that are associated with Aβ accumulation and TAU hyperphosphorylation. Here, we tested the effect of chronic administration of melatonin (MLT) on brain insulin resistance and cognition deficits caused by a high‐fat diet (HFD) in aged rats. Results showed that MLT supplementation attenuated peripheral insulin resistance and lowered hippocampal oxidative stress levels. Activated microglia and astrocytes and hippocampal levels of TNF‐α in HFD‐fed rats were reduced by MLT treatment. Melatonin also prevented HFD‐induced increases in beta‐amyloid (Aβ) accumulation and TAU phosphorylation in the hippocampus. In addition, impairments of brain insulin signaling elicited by long‐term HFD were restored by MLT treatment, as confirmed by ex vivo insulin stimulation. Importantly, MLT reversed HFD‐induced cognitive decline as measured by a water maze test, normalized hippocampal LTP and restored CREB activity and BDNF levels as well as cholinergic neuronal activity in the hippocampus. Collectively, these findings indicate that MLT may exhibit substantial protective effects on cognition, via restoration of brain insulin signaling. [ABSTRACT FROM AUTHOR]