To address the issue of fishy odor in farmed sea bass, this study investigated the effects of seasoning treatments using extracts from three medicinal and edible plants—oregano, citronella, and moringa oleifera—and their compound mixture, on fish flavor profiles. Flavor characteristics were analyzed via electronic nose, electronic tongue, free amino acid analysis, and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS). Results demonstrated that all seasoning solutions applied at a concentration of 0.3 g/100 mL effectively improved the flavor quality of sea bass fillets. Notably, the compound treatment group (oregano:citronella:moringa oleifera=1:1:1) exhibited a synergistic effect. Seasoning treatments significantly reduced (P<0.05) thiobarbituric acid (TBARS) values in fish muscle, indicating effective retardation of lipid oxidation. Concurrently, increased total color difference (ΔE) values resulted in visibly darker coloration. E-nose analysis revealed that seasoning treatments significantly attenuated sensor response values for W1W (sulfides), W2W (organosulfides), and W1S (methyl groups), corresponding to reduced levels of sulfur-containing compounds and methyl-derived off-flavors associated with fishiness. Principal component analysis (PCA) effectively discriminated among the five sample groups. E-tongue detection indicated significantly reduced acidity and bitterness values in all treatment groups compared to the control (P<0.05). The compound treatment significantly increased the total free amino acid content from 357.94 mg/100 g to 418.96 mg/100 g (P<0.05), with a marked increase in umami-related amino acids. This suggested that the seasoning treatments effectively promote amino acid release, thereby enhancing nutritional value. GC-MS analysis demonstrated a significant increase in the diversity of volatile compounds in seasoned fish. Specifically, the number of volatile compounds in the compound seasoning treatment group increased from 19 (control) to 45 types, with notable increases in alcohols and terpenes. Aldehyde content decreased, and the primary fishy odor compound, hexanal, was substantially reduced from 3207.03 μg/kg to 317.67 μg/kg. The study demonstrates that these three natural extracts, particularly in combination, can reduce the generation of fishy odor substances through multi-pathway synergistic effects, providing theoretical support for the application of natural substances in flavor enhancement of aquatic products.

This study was dedicated to developing a visualization technique based on loop-mediated isothermal amplification (LAMP) with novel molecular targets, aiming to simultaneously, rapidly, and sensitively detect Flavobacterium spp. in fresh fish meat. The whole-genome sequencing and pan-genome analysis techniques were employed to systematically mine the candidate target of the Flavobacterium genus. Five Flavobacterium strains and forty-four non-Flavobacterium strains were prepared for specificity verification of candidate target. LAMP primers were designed based on the target sequence and then the amplification system was optimized. The specificity and sensitivity of novel LAMP assay and LAMP based lateral flow dipstick (LFD) visualization method were evaluated. Finally, the anti-interference capability and the accuracy in detecting actual samples were determined. These results showed that the menB target mined in this study exhibited good specificity, and the newly established LAMP method had no cross-reactivity against 12 non-target bacteria trains in optimal conditions. The detection limits for Flavobacterium in pure cultures and mixed spiked fish meat samples were 3.3×10² CFU/mL and 3.3×10³ CFU/g, respectively. Meanwhile, the detection sensitivity and specificity of LAMP-based visualization technique in pure cultures and mixed spiked fish meat samples were comparable to those of the traditional LAMP method. Moreover, it maintained excellent detection performance even under the interference of high concentrations of contaminant bacteria and spoiled fish sample. The detection results of the LAMP-LFD visualization methods for 24 actual samples were consistent with those of the traditional culture method. The novel LAMP visualization technology established in this study provides an efficient and reliable detection method for the prevention and control of Flavobacterium contamination in food, which has important application value and promotion prospects.

To investigate whether curcumin as a polyphenol can delay the quality deterioration of ready-to-eat sea cucumber during cold storage, and the impact of adding curcumin on the ready-to-eat sea cucumber, sea cucumber was used as raw material, the weight loss rate and volume loss rate of sea cucumber during the hot processing process were determined, and the moisture content, texture characteristics, microstructure, free hydroxyproline content, free ammonia nitrogen content, soluble protein content and SDS-PAGE of ready-to-eat sea cucumber during the cold storage were measured. The secondary structure of ready-to-eat sea cucumber protein was observed by infrared spectroscopy. At the same time, the volatile substances and sensory flavor were analyzed to explore the effects of adding curcumin on the quality and flavor of ready-to-eat sea cucumber. The results showed that the addition of curcumin during thermal processing had no significant effect on the weight loss rate and volume loss rate of ready-to-eat sea cucumber. After cross-linking with curcumin, the hardness of ready-to-eat sea cucumber increased by 53.92%, the chewiness increased by 64.03%, and the moisture content decreased by 5.14%. The 35 kDa band disappeared from the protein relative molecular mass, increasing to 100, 48 kDa bands. The vibration band of secondary structure amide Ⅰ band and amide Ⅱ band shifted from 1654.1 cm⁻¹ and 1549.5 cm⁻¹ to 1657.6 cm⁻¹ and 1549 cm⁻¹, increase of β-folding, decrease of random coil, decrease of α-helix, increase of β-turn. During cold storage, the protein degradation indexes such as free hydroxyproline content, free ammonia nitrogen content and soluble protein content of ready-to-eat sea cucumber showed a significant upward trend, but after curcumin cross-linking treatment, the protein degradation rate of ready-to-eat sea cucumber was significantly slowed down. When cold storage for 40 days, the ready-to-eat sea cucumber treated with curcumin had a relative increase in volatile substances such as caramel, fruity, and smoky flavors, and the relative content of volatile substances with antibacterial and antioxidant properties increased. In conclusion, curcumin can interact with the body wall protein of sea cucumbers, thereby delaying the degradation of the body wall during refrigeration and improving its flavor.

Objective: To investigate the storage characteristics and quality evolution of fresh Radix Astragali under low-temperature of 4  ℃ and dark storage conditions. Methods: The storage characteristics and quality changes of fresh Radix Astragali at 4  ℃ were analyzed by monitoring its physiological parameters and storage quality during storage. Results: The moisture content of fresh Radix Astragali decreased from 57.92% to 48.19%, accompanied by a steady increase in weight loss, which reached 9.76% at 60 days. Respiration intensity showed a rise-then-fall trend, peaking at 15 days (15.17 CO₂ mg·kg⁻¹·h⁻¹), indicating active metabolism in the early storage stage. In the initial 30 days, overall quality remained stable; however, in the later period, sensory quality and b^* value declined significantly (P<0.05), with surface browning and texture softening. The b^* value of the cross-section decreased by 33.07% at 60 days compared to 0 day. Total flavonoid content slightly increased initially, peaking at 0.56 mg/g at 15 days, then declined markedly to 0.34 mg/g by 60 days (P<0.05). Calycosin content continuously decreased, reaching 0.0175 mg/g at 60 days. Antioxidant capacities (DPPH, ABTS⁺, and hydroxyl radical scavenging) also peaked at 15 days, but dropped by 54.81%, 17.5%, and 23.40%, respectively, at 60 days. Superoxide anion content increased significantly (P<0.05), reaching 3.92 μmol/g by 60 days. Both acid value and peroxide value increased over time, reaching 39.36 mg/g and 4.86% at 60 days, reflecting severe oxidative deterioration. With prolonged storage, decay rate and disease index increased notably. Mold appeared after 30 days, with decay rates of 8.83% and 12.57%, and disease indices of 7.34% and 10.59% at 45 and 60 days, respectively. Conclusion: A storage duration of up to 30 days at 4  ℃ under dark conditions was found to effectively preserve the sensory quality and biological activity of fresh Radix Astragali, with flavonoid levels, antioxidant capacity, and metabolic status remaining relatively stable. Beyond this period, decay became progressively severe, accompanied by a rapid decline in overall quality and antioxidant function. This study provides a theoretical foundation for optimizing postharvest storage strategies and quality control of fresh Radix Astragali.

To investigate the effect of low voltage electrostatic field (LVEF) treatment on Alternaria rot in apricot fruit, 'Chuanzhihong' apricots were used as the experimental material. The fruits were wound-inoculated with Alternaria alternata and stored under a 1500 V LVEF environment at 25±1 ℃ and 80%~85% relative humidity. Physiological and biochemical parameters were measured to evaluate the inhibitory effect of LVEF treatment on Alternaria rot development during storage. The results demonstrated that LVEF treatment significantly inhibited the infection process of the pathogen. Compared to the control (CK) group, LVEF treatment reduced the disease incidence by 41.18% and the lesion diameter by 31.20% (day 6). In terms of oxidative stress, the contents of malondialdehyde (day 2) and hydrogen peroxide (day 6) were significantly lower in the LVEF group than in the CK group, decreasing by 29.41% and 19.75%, respectively. Additionally, the production rate of superoxide anion (day 6) was also decreased significantly, showing a reduction of 5.42%. Furthermore, LVEF treatment suppressed the activity of polyphenol oxidase while increased the content of reduced glutathione by 1.81% (day 4). Regarding antioxidant enzyme activity regulation, LVEF treatment significantly enhanced the activities of catalase and ascorbate peroxidase, while peroxidase and superoxide dismutase activities were also increased. In terms of disease resistance, the activities of phenylalanine ammonia lyase and chitinase significantly increased by 5.86% and 1.17% (day 6), respectively, while the contents of total phenols and flavonoids increased by 1.75% and 4.35% (day 6). In conclusion, LVEF preservation technology could effectively inhibit the disease occurrence of Alternaria rot and showed promising application potential for controlling postharvest diseases in apricot fruit.

To improve the edible quality of ready-to-eat tangerine peel-flavored eel, this study optimized key processing parameters and established a shelf-life prediction model. First, single-factor experiments were conducted to optimize frying time, tangerine peel powder content in seasoning, and sterilization method. Then, the quality changes of eel products during storage at different temperatures (37, 25, 10 ℃) were monitored, Finally, the shelf-life prediction models were developed based on the kinetic equations and the Arrhenius equation. Results showed that the optimal frying time was 4 minutes, the content of tangerine peel powder in seasoning was 10%, and the sterilization method was the combination of high-temperature and irradiation sterilization. With the extension of storage time, the total viable count (TVC), total volatile basic nitrogen (TVB-N), and thiobarbituric acid (TBA) values of eel products gradually increased, while sensory scores gradually decreased. The pH exhibited a trend of direct decrease when samples stored at 37 ℃, while decrease followed by increase when samples stored at both 25 and 10 ℃, indicating progressive quality deterioration. Shelf-life prediction models for TVC, TVB-N, and TBA, respectively, were established. Validation results showed that the prediction model based on TVC had the minimal relative error (all below 5%), therefore, the TVC model was recommended as the suitable shelf-life prediction mode for ready-to-eat tangerine peel-flavored eel.

To investigate the effects of ultra-high pressure sterilization on the quality of low-fat walnut sauce and predict its shelf life, the optimal ultra-high pressure sterilization conditions were selected. Moreover, multivariate statistical analysis was employed to comparatively evaluate the impacts of ultra-high pressure sterilization (HPP), high temperature steam sterilization (HPST), and pasteurization (PS) on the multi-dimensional quality indices of low-fat walnut sauce, so as to screen out the appropriate sterilization method. Furthermore, based on the Arrhenius equation, shelf life prediction models under different storage conditions (4, 25 and 35 ℃) were constructed. The research results showed that HPP could better retain the original quality of low-fat walnut sauce. The low-fat walnut sauce treated by HPP (500 MPa, 4 min) had the best color, relatively high adhesiveness, moderate hardness, cohesion, chewiness, and good stability. Through the application of gas chromatography-ion mobility spectrometry (GC-IMS) combined with Orthogonal Partial Least Squares Method (OPLS-DA), 26 key volatile compounds were identified from low-fat walnut sauce. ROAV analysis revealed that 3-methylbutyral was the dominant flavor compound, primarily contributing mushroom and fruity aromas. The HPP group exhibited (E)-2-heptenal as its primary flavor component, mainly presenting grassy and cucumber-like notes. Principal component analysis demonstrated that HPP-treated low-fat walnut sauce achieved optimal overall quality (comprehensive score 1.52), serving as the most effective sterilization method. Additionally, shelf life predictions indicated 118 days under 4 ℃ storage conditions. This study provides theoretical references for quality improvement in low-fat walnut sauce production.

In order to investigate the optimal extraction process of sulforaphane from broccoli seeds and evaluate its immunomodulatory activity, broccoli seeds as the raw material, the effects of parameters including solid-liquid ratio, ethanol concentration, extraction time, extraction temperature and extraction times on the yield of sulforaphane were examined. The parameters were optimized by orthogonal experimental design. The immunomodulatory activity of its extract contains sulforaphane was explored based on the immunodeficiency zebrafish model. The results indicated that the highest yield of sulforaphane was 18.24 mg/g under the conditions of a 1:22 g/mL solid-liquid ratio, ethanol concentration of 10%, 1 h of extraction time, 40 ℃ of extraction temperature and two extraction circles. The immunomodulatory activity tests showed that the extract contains sulforaphane had strong immunomodulatory activity and could significantly enhanced macrophage phagocytosis in zebrafish at high dosage (200 μg/mL) and medium dosage (100 μg/mL), improve T cell reduction at medium dosage (100 μg/mL) and low dosage (50 μg/mL), and improve neutropenia at high dosage (200 μg/mL), medium dosage (100 μg/mL) and low dosage (50 μg/mL). By optimizing the extraction process of sulforaphane from broccoli seeds and evaluating its immunomodulatory activity, the study provided a theoretical and practical basis for the research and application of the extract contains sulforaphane.

This study aimed to investigate the effect of steam-exploded insoluble dietary fiber from Flammulina velutipes root (SE-IDF) on blood lipids and liver protection. The insoluble dietary fiber was prepared using an enzymatic method, and its chemical composition and fundamental physicochemical properties were characterized. A hyperlipidemia model was established in C57BL/6J male mice (n=40) induced by high-fat diet feeding. Mice were randomly divided into five groups: Normal diet group (ND), high-fat diet group (HFD), and three SE-IDF treatment groups with low (SE-IDFL, 50 mg/kg), medium (SE-IDFM, 100 mg/kg), and high doses (SE-IDFH, 200 mg/kg). After 10 weeks of intervention, serum and hepatic levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were measured. In addition, serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lipopolysaccharide (LPS), and interleukin-6 (IL-6) were assessed. Hepatic oxidative stress markers, including total superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and malondialdehyde (MDA), were also determined. Hepatic steatosis and lipid distribution were assessed by hematoxylin-eosin (HE) and oil red O staining to evaluate pathological changes in liver tissue. The results indicated that the contents of cellulose, hemicellulose, and lignin in Flammulina velutipes root were significantly reduced by steam explosion treatment. Compared with IDF without steam explosion treatment, the oil holding capacity and cholesterol binding capacity of SE-IDF were obviously improved, resulting in good oil adsorption capacity. Animal experiments demonstrated that, compared with the HFD group, the SE-IDFH group significantly reduced serum and hepatic TC, TG, and LDL-C levels (P<0.05), and increased HDL-C levels (P<0.05). All SE-IDF treatment groups enhanced SOD and CAT activity as well as GSH levels, while decreasing MDA, LPS, and IL-6 concentrations, thereby alleviating inflammation and oxidative stress induced by a high-fat diet. SE-IDFM and SE-IDFH groups markedly improved liver histopathological structure, reduced hepatic lipid droplet area, vacuole formation, and inflammatory infiltration. These findings suggest that SE-IDF can effectively improve dyslipidemia in hyperlipidemic mice, reduce hepatic lipid accumulation, and exert hypolipidemic, hepatoprotective, and anti-fatty liver effects.

A novel swim bladder glue (SBG) was prepared with reference to the traditional processing technology of E'Jiao. The changes in its physicochemical properties and Maillard reaction products during preparation were systematically analyzed, and compared with unprocessed swim bladder collagen (SBC) and commercial EJ. An ovariectomized (OVX) osteoporosis mouse model was established to evaluate therapeutic efficacy, with femoral bone density assessed via micro-computed tomography (Micro-CT) and hepatic histopathology examined through H&E staining. Results demonstrated that SBG predominantly contained low-molecular-weight peptides (<5 kDa), with disrupted microstructure, altered secondary structure, and increased free amino acid content. In contrast, EJ and SBC exhibited dense microstructures and higher molecular weight distributions (>10 kDa). In terms of Maillard reaction, during the preparation of SBG, the contents of mid-stage Maillard reaction products (Maillard fluorescent substances, 5-hydroxymethylfurfural [HMF]) and late-stage product melanoidins all showed an upward trend, with a marked increase, particularly during the concentration stage. The reaction process was dominated by the mid-stage Maillard reaction. In contrast, EJ contained a high level of melanoidins and was mainly in the late stage of the Maillard reaction, while the Maillard reaction degree of SBC was low. SBG significantly increased femoral bone mineral density (BMD) in ovariectomized mice, with the high-dose SBG group (SBGH) exhibiting the most pronounced effect (206.44±17.65 mg/cm³). Moreover, SBG significantly alleviated liver inflammation, whereas neither EJ nor SBC significantly increased BMD or ameliorated liver inflammation. This study systematically analyzed the evolution of physicochemical properties and dynamic changes of Maillard reaction products during the preparation of SBG, and evaluated its bone density-improving function. The findings provide a theoretical basis for promoting the deep exploitation of swim bladder resources and elucidating the material basis of the medicinal efficacy of gelatinous traditional Chinese medicines.