Effects of wheat gluten-soy protein ratios and moisture levels on high-moisture extruded meat analogues for burger patties
In response to the growing demand for plant-based meat alternatives, this study explores the impact of incorporating wheat gluten (WG) into soy protein isolate (SPI) on both the proximate and functional properties of protein blends. The research also examines the effects of high moisture extrusion processing, varying feed moisture levels (60%, 65%, and 70%), and WG-SPI blends on extruder response, as well as the textural, rheological, and solubility characteristics of the resulting extruded meat analogues. Moreover, the prime objective was to gain insights into the impact of using HMMA made at different ratios and feed moisture levels on plant-based burgers. As the WG incorporation level increased in SPI, the RVA viscosity, water absorption, and oil absorption capacities, and foaming stability exhibited a decrease while foaming capacity increased. As feed moisture and WG incorporation levels in SPI increased, the system parameters, rheological, and textural parameters of high moisture extruded meat analogs decreased. WG25-SPI75 showed the highest degree of texturization or sulfide bonds, and its extruded meat analogues at 60% feed moisture level burger patties resemble a similar textural to a chicken burger patty. This study is pivotal in understanding how wheat gluten in SPIs and feeding moisture level influence the textural and rheology properties of HMMA.
Storage quality of amylose-lycopene complexes and the establishment of a shelf life prediction model
To study the changes in the storage quality of amylose-lycopene complexes (ALCs), the color, antioxidant activity, lycopene content, and configuration changes of ALCs during different storage periods were analyzed. A shelf life prediction model was established to reveal the stability changes of the complexes. The results showed that the cis-isomer percentage of lycopene in ALCs increased significantly from 11.82% to 13.76%. The lycopene isomers were in the order of 5-Z > All-E > 9-Z > 13-Z. Correlation analysis indicated that the content of lycopene was a key factor affecting the quality of ALCs. ALCs followed zero-order and first-order degradation kinetics at 5°C-25°C and 35°C-45°C, respectively. The degradation degree of lycopene was negatively correlated with temperature, with half-lives and one-tenth decay periods of 32.37 days and 6.48 days (5°C) significantly higher than 10.78 days and 1.63 days (45°C). The activation energy required for the reaction of ALCs was as high as 106.29 kJ/mol, indicating greater stability. On this basis, an ALCs shelf life prediction model was established, with a relative error of 0.06%-5.03% between the predicted and actual values. The results indicated that ALCs had good color, antioxidant activity, lycopene content, and configuration stability, and that higher temperatures had a greater impact on lycopene. The study provides theoretical reference for the quality safety of ALCs.
Improving the bioactivity of water-soluble alfalfa saponins using biotransformation
Medicago sativa L. is gaining attention as a sustainable plant-based food protein. Alfalfa saponins (ASs) typically exist in a glycosylated form in nature, which has poor cell membrane permeability, while the deglycosylated saponins may show better bioactivity. The AS was deglycosylated by β-glucosidase from Aspergillus niger, and the chemical structures and biological activities, including in vivo assays, of AS and deglycosylated AS (DAS) were determined. The results showed that the half maximal inhibitory concentration for 2,2-diphenyl-1-picrylhydrazyl inhibition of DAS was 29.5 µg/mL, demonstrating a significantly higher reducing capacity compared to AS (p < 0.05). The DAS induced 33.8% antibacterial activity against Escherichia coli and enhanced the proliferation of human airway epithelial cells (BEAS-2B) at a concentration of 125 µg/mL. In vivo experiments on C57BL/6 mice fed a high-fat diet demonstrated that high-level DAS treatment produced significantly greater hypolipidemic effects compared to AS (p < 0.05). Thus, the AS can be deglycosylated, which leads to an improvement in biological activity, particularly since the DAS exhibits significantly enhanced hypolipidemic activity. PRACTICAL APPLICATION: Alfalfa saponins were deglycosylated by β-glucosidase from Aspergillus niger, which contributed to increased bioactivity, particularly its hypolipidemic activity.
Characteristics of whey protein concentrate/egg white protein composite film modified by transglutaminase and its application on cherry tomatoes
In order to obtain food packaging film with better performance, whey protein concentrate (WPC) and egg white protein (EWP) were used as film-forming substrates, and its film properties were modified by transglutaminase (TG). Then the effect of TG on the mechanical, physical, barrier, and microstructural properties of the WPC/EWP composite biodegradable film was investigated, and its preliminary application potential was explored. Compared to WPC and EWP films, WPC/EWP composite film had higher transmittance, tensile strength (TS), and thermal stability. Fluorescence results showed that the film experienced fluorescence quenching after TG treatment. Fourier transform infrared and x-ray diffraction results showed that WPC and EWP had good compatibility in the biodegradable film, the hydrogen bond interaction of film was increased due to TG, resulting in an increase in TS. Meanwhile, the water vapor permeability and contact angle of WPC/EWP film treated with TG at 5 U/g protein increased by 28% and 76.1%, respectively. Besides, the WPC/EWP biodegradable film modified by TG (TG-W/E) was applied as a coating film on cherry tomatoes, effectively reducing the weight loss rate during storage from 14.2% to 10.8%. Furthermore, indexes, such as solid content, spoilage rate, hardness, pH, and lycopene, showed that the film had a good preservation effect on cherry tomatoes. To conclude, the appropriate addition of TG has a positive effect on the film properties of the WPC/EWP biodegradable film, which is beneficial to the development and utilization of protein-based film. WPC/EWP biodegradable film modified by TG has a great application prospect in extending the shelf life of fruit and vegetable.
Preventive potential of chitosan self-assembled coconut residue dietary fiber in hyperlipidemia: Mechanistic insights into gut microbiota and short-chain fatty acids
Hyperlipidemia is a metabolic disorder resulted from unhealthy dietary and lifestyle habits. Its pathogenesis is possibly linked to gut microbiota dysbiosis. This study investigates the preventive effects of chitosan self-assembled coconut residue dietary fiber (CRFSC) on hyperlipidemia induced by a high-fat diet (HFD) and gut microbiota. CRFSC resulted in a significant weight loss of 7.9% in HFD rats and had a preventive effect on all four lipid parameter abnormalities. HFD supplemented with oat group resulted in a weight loss of 3.8% in HFD rats and had no preventive effect on low-density lipoprotein cholesterol (LDL-C) abnormalities. Prevention was achieved not only through the modulation of gut microbiota composition and the increase of short-chain fatty acids (SCFAs) levels, but also through the activation of superoxide dismutase enzyme and the inhibition of malondialdehyde accumulation, all of which are the factors leading to the controlling of lipid abnormalities and oxidative damage. The prevention of lipid parameters by chitosan self-assembled coconut residue dietary fiber (CRFSC) may be attributed to its richness in chitosan and insoluble dietary fiber, as well as its ability to enrich beneficial bacteria such as Akkermansia, Roseburia, and Ruminococcus. Correlation analysis demonstrated that key bacterial species producing SCFAs, which are rich in the CRFSC diet, had a positive impact on controlling hyperlipidemia. Hence, consumption of a CRFSC diet could serve as an effective strategy for preventing and controlling the development of hyperlipidemia due to its potential ability to regulate gut microbiota and SCFAs. PRACTICAL APPLICATION: This study showed that dietary fiber from coconut residue after chitosan self-assembly had preventive effects on overweight, dyslipidemia, and oxidative damage in rats. In addition, CRFSC also increased the content of short-chain fatty acids in the gut. And improve gut health by affecting gut microbiota. This finding suggests that CRFSC can be used as a dietary strategy to prevent hyperlipidemia and has practical significance in developing new healthy foods.
Trypsin from digestive tract of harpiosquillid mantis shrimp: Molecular characteristics and the inhibition by chitooligosaccharide and its catechin conjugate
Trypsin from the digestive tract of harpiosquillid mantis shrimp (HMS) was purified using ammonium sulfate precipitation and a soybean trypsin inhibitor-CNBr-activated Sepharose 4B affinity column. The purified trypsin (PTRP-HMS) had a purity of 30.4-fold, and a yield of 14.5% was obtained. PTRP-HMS had the molecular weight of 23.0 kDa as examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and only one isoform was detected by native-PAGE. Its optimal temperature and pH were 55°C and 8.5, respectively. TLCK almost completely inhibited the activity of trypsin. The PTRP-HMS had a Michaelis-Menten constant (K) and catalytic constant (K) of 0.87 mM and 13.04 s, respectively, toward Nα-benzoyl-l-arginine 4-nitroanilide hydrochloride. When chitooligosaccharide (COS) and COS-catechin (COS-CAT) conjugates were examined for inhibition toward the PTRP, the latter exhibited higher efficacy in inhibiting the trypsin. Both COS and COS-CAT conjugate showed mixed-type inhibition kinetics. As a consequence, COS and COS-CAT conjugate could be used as natural additives for inhibiting trypsin in whole HMS, thus retarding the softening and lengthening the shelf-life of HMS during the iced storage. PRACTICAL APPLICATION: Harpiosquillid mantis shrimp (HMS) is of high demand due to its delicacy. However, its meat undergoes rapid softening within 2-3 days when stored in ice. Understanding causative proteolytic enzymes, especially trypsin from digestive tract, paves a way for preventing their negative impact on HMS eating quality. Employment of safe inhibitors, for example, chitooligosaccharide (COS) or COS conjugated with catechin, could inhibit HMS trypsin. Overall, softening of whole HMS containing trypsin in its digestive tract can be impeded, especially when treated with COS-CAT. This finding is beneficial for the HMS local vendor or exporter, in which HMS quality can be maintained.
Preparation of functional supplement powder using nanoliposome-containing marine bioactive compounds
The demand for marine bioactive compounds as therapeutic agents in supplements or functional foods has increased. However, their instability, bitter taste, and potential degradation during digestion have hindered their widespread use. To overcome these problems, a functional supplement powder was produced using the encapsulation technique of nanoliposomes containing shrimp lipid extract, fish oil (FO), and fish protein hydrolysate. Chitosan and whey protein concentrate (WPC) were used to coat the nanoliposomes in mono/bilayer and composite forms, followed by freeze-drying for 72 h. The physicochemical characteristics, nutritional, in vitro release, and sensory evaluation were investigated. The WPC-monolayer treatment exhibited the highest solubility (28.83 mg/100 g), encapsulation efficiency (97.67%), and polyunsaturated fatty acids (PUFAs). Although the mono/bilayer treatments of whey protein showed lower docosahexaenoic acid and eicosapentaenoic acid than FO, they presented a favorable amino acid profile. Compared to acidic stomach conditions, the release in the intestine was higher. Incorporating 1.5 g of the supplement powder per 100 g of milk can meet an individual's daily nutritional needs for essential amino acids and PUFAs. Therefore, encapsulating marine bioactive compounds in liposomal carriers could be a beneficial approach to their direct use as a nutritious powder.
Mass transfer kinetics of ultrasonic- and vacuum-ultrasonic-assisted static brine of chicken breast (Pectoralis major)
The aim of this study was to investigate the effect of different ultrasound treatment (UT) conditions (Control, UT-150, UT-300, UT-450, Vacuum-UT-150, Vacuum-UT-300, Vacuum-UT-450) on the brining kinetics and meat quality of chicken breast. The results showed that vacuum-ultrasonic-assisted treatment greatly accelerated the transfer of moisture and NaCl, and the highest yield was obtained by ultrasonic power of 450 W. The mass transfer kinetics (k and k) were significantly related to vacuum pretreatment and ultrasonic power. The values of k for total and moisture weight changes decreased with the increase of ultrasonic power, whereas the values of k increased with vacuum pretreatment. The application of ultrasound treatment with vacuum improved the NaCl effective diffusion coefficients (D) from 1.189 × 10 to 1.308-1.449 × 10 m/s, and the highest De was found with Vacuum-UT-450. The treatment of ultrasound and vacuum can reduce shear force and enhance the water-holding capacity (WHC). According to the analysis of water distribution, vacuum and ultrasound could decrease the T values, indicating that the mobility of water decreased. The result of microscopic observation further supported that the disruption of myofibrils was related to the tenderness and WHC changes, which was caused by vacuum and ultrasound treatment. Thus, Vacuum-UT brining could be employed as an emerging technology for improving the efficiency of brining and meat quality of other meat. PRACTICAL APPLICATION: Vacuum-ultrasonic-assisted static brine is an effective and feasible treatment to replace tumbling treatment for maintaining the integrity of the muscle bundles and accelerating the brining rate.
Extraction of high-quality Antarctic krill (Euphausia Superba) oil using low-temperature continuous phase-transition extraction equipment
The aim of this study was to explore a processing method for efficient extraction of high-quality krill oil (KO) using a low-temperature continuous phase-transition extraction equipment (LCPE). The efficiency of lipid extraction and quality of KO and defatted krill meal (DKM) by LCPE were compared with those of supercritical CO and n-hexane extraction. Results showed that compared to other methods, extraction using LCPE had the highest lipid yield (21.72 ± 0.34%), bioactive substances, and dimethyl sulfide (3.12 ± 0.09 mg/kg), the lowest oxidative deterioration. Moreover, compared to other methods, DKM extracted by LCPE had the lowest fat (<2%), the highest protein (>60%), and the best oxidative stability. These benefits would ensure easier transportation and better long-term storage, allowing for its application on distant-ocean fishing vessels. Therefore, LCPE is a method that allows for efficient extraction of high-quality KO.
Weizmannia coagulans BC99 affects valeric acid production via regulating gut microbiota to ameliorate inflammation and oxidative stress responses in Helicobacter pylori mice
Helicobacter pylori is a highly prevalent pathogen in human gastric mucosa epithelial cells with strong colonization ability. Weizmannia coagulans is a kind of active microorganism that is beneficial to the improvement of host gut microbiota balance and can prevent and treat intestinal diseases. We investigated the beneficial effects of W. coagulans BC99 in H. pylori infected mice and measured inflammation response, oxidative stress, and gut microbiota. Results showed that BC99 could alleviate the gastric inflammation, inhibit the increasing of inflammation parameters endotoxin, interleukin-10, transforming growth factor-β, and interferon-γ and oxidative stress myeloperoxidase and malondialdehyde, promote the levels of superoxide dismutase and catalase. Furthermore, 16S rRNA gene sequencing analysis revealed that BC99 reversed the change of gut microbiota by reducing the abundance of Olsenella, Candidatus_Saccharimonas, Monoglobus, and increasing the abundance of Tyzzerella. Meanwhile, BC99 caused elevated levels of Ligilactobacillus and Lactobacillus. In view of the beneficial effect of BC99 on the content of short-chain fatty acid, valeric acid with sodium valerate interfered with H. pylori infection in mice found that valeric acid had a good restorative effect of H. pylori infection relating inflammation and oxidative stress responses. These results suggest that W. coagulans BC99 can be used as a potential probiotic to prevent and treat H. pylori infection by regulating the inflammation, oxidative stress, and gut microbiota.
Plant-based mince texture: A review of the sensory literature with view to informing new product development
The texture of plant-based meat alternatives is a sensory attribute that holds a central value in consumer acceptability. The texture dimensions and drivers of liking for plant-based mince, a popular product within plant-based meats, are not yet fully established and literature in this area is limited. Consequently, the successful development and positioning of such products in the market next to traditional proteins is compromised, and improved product development guidelines are needed for the industry. This review aims to inform product development of what is currently known about plant-based mince texture and where the research gaps are, particularly with respect to sensory dimensions and drivers of liking, by reviewing the present landscape of relevant sensory literature. Potential texture sensory dimensions for plant-based mince, based on limited studies and seemingly aligning with conventional mince, are posited as juiciness, tenderness, firmness, and/or softness with a key driver of liking being juiciness, but this requires further validation utilizing robust sensory studies. A significant need exists to expand on the currently known texture dimensions and drivers alongside new ways that texture can be improved upon to more closely align to, or exceed, consumer expectations. Once this has been achieved, a robust sensory framework for developing plant-based mince products can be used to better position plant-based mince to effectively compete with traditional mince, and not merely cannibalize upon other brands, in the current market.
Effect and mechanism of different exogenous biomolecules on the thermal-induced gel properties of surimi: A review
Surimi products are favored by domestic and foreign consumers due to their distinctive gelatinous texture, rich nutrition, and convenient consumption. Gel properties are key evaluation indicators for the quality of surimi products, which was mainly determined by the gel-forming ability of the myofibrillar protein (MP). In recent years, the surimi processing industry has faced challenges in product quality that limits the further development, and how to effectively improve the gel properties of surimi products has become one of the key scientific problems to be solved in surimi processing industry. A viable strategy for improving the product quality involves combining surimi with exogenous additives, such as proteins, polysaccharides, and lipids, to enhance the gel-forming ability of MP. At present, there is limited literature review to systematically investigate the role of these exogenous additives in interacting with MPs in surimi gel system and their effect on the gel properties of heat-induced surimi. Therefore, in this review, we systematically discussed the formation mechanism and influencing factors of surimi gel, the interactions of exogenous biomolecules (proteins, polysaccharides, and lipids) with surimi protein, as well as their effects on the gel properties of surimi product. The aim of this review was to help us with a better understanding for the intrinsic action mechanisms of complex surimi system and provide some theoretical guidance for the improvement of gel quality and development of surimi products.
Jerked beef as an ultraprocessed convenience food: Desalting strategies to minimize the impact on lipid and protein oxidation
Jerked beef (JB) is a high-protein convenience food but shows high degree of oxidation owing to its severe ultraprocessing. This study aimed to investigate the effect of desalting processes on oxidative stability of JB. JB were submitted to five desalting procedures: immersion in water at room temperature for 12 h without changing the water (AT12); immersion in water at room temperature for 12 h followed by boiling for 30 min and changing the water between the two procedures (AT12 + C30); immersion in boiled water for 10, 20, and 30 min (C10, C20, and C30, respectively). The desalted JB samples were refrigerated (vacuum packed and stored at 1 ± 1°C) and analyzed at 0 and 60 days. The samples without desalting were used as a control group. AT12 samples had the lowest lipid oxidation (0.05 and 0.07 mg of MDA kg, at T60 and T0, respectively). AT12 + C30 had the lowest NaCl content (2.8 and 3.3 g 100 g, at T0 and T60, respectively). C10, C20, and C30 showed a lower level of total carbonyls (p < 0.05) (0.04-0.13 nmol mg protein), compared to control (0.53-0.93 nmol mg protein in T0 and T60, respectively). Only boiled, desalted meats showed the volatile compound benzaldehyde. Higher concentration of monounsaturated, polyunsaturated, and total unsaturated fatty acids in JB desalted only in boiling water (C10, C20, and C30), compared to control (p < 0.05). AT12 is the best process to use, with regards to lipid oxidative stability, hardness, and NaCl content. Therefore, we conclude that it is possible to offer commercially desalted JB, as a convenience ultraprocessed product. PRACTICAL APPLICATION: Lipid oxidation is accelerated when desalting jerked beef (JB) with boiling water. Desalted JB in boiling water had detectable concentrations of benzaldehyde. •Desalting in water at 25°C/12 h resulted in JB with better oxidative stability.
Cross-linked Arenga pinnata (Wurmb.) Merr. starch and chitosan with sodium trimetaphosphate: Structure, physicochemical properties and in vitro digestibility
The inherent limitations of native starch considerably restrict its applications in the food industry. To enhance its processing properties, Arenga pinnata (Wurmb.) Merr. starch (APS) was subjected to dual modification with low levels of sodium trimetaphosphate (0%, 1%, and 3%) and chitosan (1%) to investigate its physicochemical, thermal, pasting, and in vitro digestibility. The dual modification of APS significantly increased the degree of cross-linked (CLD) to 84.69%, resulting in a rougher surface texture. This process led to the formation of phosphate bonds, the weakening of hydrogen bonds, and a decrease in relative crystallinity, all while preserving the starch's crystalline structure. Additionally, the modification impeded paste formation, reduced swelling power, and lowered pasting enthalpy, while increasing the content of slowly digestible starch and resistant starch. These findings provided a basis to enhance the functional properties of starch-based materials, which could be applied to improve the texture and stability of food products such as sauces, dressings, and desserts in the food industry.
Chlorella vulgaris as a food substitute: Applications and benefits in the food industry
Chlorella vulgaris, a freshwater microalga, is gaining attention for its potential as a nutritious food source and dietary supplement. This review aims to provide a comprehensive discussion on C. vulgaris, evaluating its viability as a food substitute in the industry by exploring the nutritional value and application of C. vulgaris in the food industry. Rich in protein, lipids, carbohydrates, vitamins, and minerals, Chlorella offers substantial nutritional benefits, positioning it as a valuable food substitute. Its applications in the food industry include incorporation into smoothies, snacks, and supplements, enhancing the nutritional profile of various food products. The health benefits of Chlorella encompass antioxidant activity, immune system support, and detoxification, contributing to overall well-being. Despite these advantages, the commercialization of Chlorella faces significant challenges. These include variability in antibacterial activity due to strain and growth conditions, high production costs, contamination risks, and sensory issues such as unpleasant taste and smell. Additionally, Chlorella can accumulate heavy metals from its environment, necessitating stringent quality control measures. Future prospects involve improving Chlorella strains through genetic manipulation to enhance nutrient content, developing cost-effective culture systems, and exploring advanced processing techniques like pulsed electric fields for better digestibility. Addressing sensory issues through flavor-masking strategies and employing environmental management practices will further support Chlorella's integration into the food industry. Although C. vulgaris shows great potential as a nutritious food ingredient, overcoming existing challenges and optimizing production methods would be crucial for its successful adoption and widespread use.
Influence of (ultra-)processing methods on aquatic proteins and product quality
Aquatic products are a high-quality source of protein for humans, and the changes in protein during aquatic product processing are crucial for nutritional value, product performance, and consumer health. With the advancement of science and technology, aquatic product processing methods have become increasingly diverse. In addition to traditional methods such as thermal processing (steaming, roasting, and frying) and pickling, emerging non-thermal processing technologies, such as high pressure, ultrasound, and irradiation, are also being applied. During (ultra-)processing, aquatic products undergo complex biochemical reactions, among which protein oxidation significantly affects the quality of aquatic products. Protein oxidation can alter the molecular structure of proteins, thereby changing their functional properties and ultimately impacting product quality. This paper primarily explored the effects of protein changes under different processing methods on aquatic product quality and human health, as well as techniques for controlling protein oxidation. It aims to provide a theoretical basis for selecting appropriate processing methods, improving aquatic product quality, and controlling protein oxidation in aquatic products, and to offer scientific guidance for practical production.
How ultrasonication treatment drives the interplay between lysinoalanine inhibition and conformational performances: A case study on alkali-extracted rice residue protein isolate
Lysinoalanine (LAL) formed during alkaline extraction of rice residue protein (RRPI), which limited its application in the food industry. In this study, the influence of ultrasonication parameters (acoustic power density, ultrasound duration, and ultrasound temperature) on the inhibition of LAL formation and conformational attributes of RRPI during alkaline extraction was elucidated. The results suggested that the acoustic power density substantially modified the chemical interaction forces between RRPI molecules. At a power density of 60 W/L, the ionic bonds (14.37%) and hydrophobic interactions (49.28%) reached the maximum, while hydrogen bonds (15.29%) and disulfide bonds (21.06%) reached the minimum. Moreover, acoustic power density at 60 W/L caused a decrease of 18.02% and 12.2% in α-helix, and β-turn, respectively, shifting toward β-sheet, random coil, with an increase of 7.31% and 36.16%. Following ultrasonication, the protein particle size distribution curve shifted in the direction of smaller particle size, forming a relatively concentrated and uniform protein distribution. Sonication power, temperature, and time decreased the absolute value of Zeta potential. Furthermore, significant destruction in microstructure was elicited by sonication, which made the structure looser and more microparticles. Pearson correlation analysis suggested that the inhibition in the levels of LAL was most influenced by the increase of sulfhydryl groups and Zeta potential, as well as the reduction of α-helix content, in which the alteration of the total sulfhydryl group content had a great impact on the Zeta potential and the free sulfhydryl group. The principal component analysis demonstrated a notable correlation between the total sulfhydryl group and both the Zeta potential and free sulfhydryl group of RRPI.
Antioxidant peptides from silver carp steak by alkaline protease and flavor enzyme hydrolysis: Characterization of their structure and cytoprotective effects against HO-induced oxidative stress
Silver carp steak is a rarely utilized silver carp processing byproduct. This study aimed to optimize a dual enzymatic method to extract antioxidant peptide components from silver carp steak and characterize their structure and in vitro antioxidant activity through ultrafiltration purification, response surface methodology, molecular docking, and radical scavenging activity analysis. The optimal extraction conditions for silver carp steak antioxidant peptides (SCSAP) were determined as 1:6 solid-liquid ratio, 1500 U/g alkaline protease addition, 4 h alkaline protease hydrolysis time, 1946 U/g flavor enzyme addition, and 2.5 h flavor enzyme hydrolysis time. The <3 kDa SCSAP component (SCSAP-3kDa) showed the strongest antioxidant activity, with its 1,1-diphenyl-2-trinitrophenyl hydrazine (DPPH) radical scavenging rate, ABTS radical scavenging rate, hydroxyl radical scavenging rate, metal ion chelating rate, and reducing capacity reaching 88.75%, 91.21%, 67.02%, 69.07%, and 0.985, respectively. Moreover, the three peptides (PF-7, GP-8, and YF-10) of 100 µg/mL could protect HepG2 cells from oxidative stress damage by reducing the oxidative damage level and activating Keap1-Nrf2-ARE pathways, enabling an increase of superoxide dismutases (SOD) activity, and a decrease of malondialdehyde (MDA) content and reactive oxygen species (ROS) level. The integrated results indicate the enormous potential of SCSAP-3kDa as a functional food ingredient in the food industry. PRACTICAL APPLICATION: This study selected the antioxidant capacity of silver carp steak peptides as the index and developed a facile dual enzymatic hydrolysis method to obtain three antioxidant peptides (PF-7, GP-8, and YF-10) with biological activity, providing a theoretical basis for bioavailability of antioxidant peptides from silver carp steak and contributing to their application in new functional foods.
A nonlinear association between total selenium intake and blood selenium concentration: An analysis based on the National Health and Nutrition Examination Survey 2011-2018
Diets are the major sources of selenium (Se) and biomonitoring Se is used for the assessment of Se status. The present study explored the association between Se intake and blood Se concentration from the National Health and Nutrition Examination Survey 2011-2018 data for optimizing Se reference intakes among American adults and interpreted the data in the context of exposure guidance values. Weighted linear regression models were conducted to evaluate the association between Se intake and blood Se concentration. Restricted cubic spline models were employed to explore the dose-response association between total Se intake and blood Se concentration. Blood Se concentrations were compared to biomonitoring equivalents established for exposure guidance values. For gender, race, educational status, poverty income ratio, body mass index, smoking status, dietary Se intake, and total Se intake, significant differences were observed among quartiles of blood Se concentration. There was no significant difference for age and alcohol use. There was a positive association between dietary Se intake and blood Se concentration although the association was not statistically significant following the adjustments for covariates. When the associations between total Se intake and blood Se concentration were assessed, no statistically significant relationship was found. The restricted cubic spline supported a significant nonlinear association between total Se intake and blood Se concentration with/without the adjustments of covariates. The present work displayed a baseline for Se exposure among American adults. Considering the sex difference in dietary Se and blood Se concentration, it is necessary to establish gender-based Se reference intakes.