The effects of different heat treatments (80 ℃/LH, 100 ℃/MH, 120 ℃/HH) on the flavor of gonggan (Citrus reticulata Blanco var. gonggan) juice were evaluated using sensory evaluation, E-nose and HS-SPME-GC-MS. Significant volatile differences were observed. D-limonene, linalool, and decanal (high OAVs) were well preserved in control and LH. MH slightly reduced major alcohols/aldehydes, introduced mild sour/herbal flavors, and generated new compounds. HH markedly altered volatiles, producing 24 off-flavor compounds (e.g., p-vinylguaiacol) and sharply decreasing linalool OAV (514.04). Sensory aroma scores: LH highest (83.85 ± 9.16), followed by MH (74.23 ± 13.99) and control (69.23 ± 18.15), HH lowest (24.38 ± 18.91). LH preserved/enhanced citrus-floral aroma, while HH promoted off-flavors. These results guide thermal processing to improve sensory acceptance of heat-treated gonggan juice.

Mango peel, an agricultural byproduct rich in liposoluble carotenoids and pectin, presents challenges for valorization due to the poor bioavailability of carotenoids. This study proposes an innovative strategy termed ‘pectin-pigment co-utilization,’ which employs peel-derived high-ester pectin (DE = 78.58%) as a natural emulsifier to encapsulate endogenous carotenoids. Compared to commercial pectins, mango peel pectin demonstrates superior emulsifying properties, including a lower molecular weight, higher hydrophobicity (water contact angle: 71.86°), reduced surface tension (41.25 mN/m), and an enhanced oil-holding capacity. These characteristics confer excellent stability to the resulting emulsion. In vitro digestion studies revealed that this emulsion increased carotenoid bioaccessibility by 61.09% compared to free carotenoids, significantly outperforming commercial pectin-based systems. When used as a fat replacer in ice cream, the emulsion enhanced viscosity, reduced melting rate, and improved antioxidant activity. Volatile profiling indicated a shift from dairy-dominant to plant-derived aroma, characterized by increased terpene alcohols, aldehydes, and esters. Sensory evaluation indicated optimal overall acceptability at 50% substitution, where enhanced texture and color were balanced with maintained flavor acceptance. This work presents an integrated strategy for valorizing mango peel into a functional delivery system, contributing to the development of nutritious, low-fat ice cream with improved physicochemical and sensory properties.

[This corrects the article DOI: 10.3389/fbioe.2022.989893.].

In this study, we evaluated the effects of microwave (MW), irradiation (IR), and low-temperature plasma (LTP) treatments on the storage quality of mango powder. The results showed that while IR exhibited the strongest antimicrobial effect, LTP demonstrated comparable or superior efficacy to MW in preserving sensory quality, solubility, and bioactive compounds, and it excelled in maintaining flavor complexity. A backpropagation neural network was constructed and could accurately predict sensory changes during storage. Flavor analysis identified 172 key aromatic compounds, with terpenes being dominant. Overall, LTP emerged as a highly promising non-thermal technology, offering a balanced and effective approach for quality retention, without the concerns associated with MW scaling-up for industrial application or residual risks of IR, providing a compelling alternative for the fruit powder processing industry.

Finger Citron (Citrus medica L. var. sarcodactylis Swingle) holds significant potential as both a culinary ingredient and a traditional medicinal remedy; however, its precise molecular mechanisms of action remain largely unexplored. This study investigates the anti-inflammatory properties of Finger Citron extract (FCE) in RAW 264.7 macrophages stimulated by lipopolysaccharide (LPS). Using UPLC-ESI-QTF-MS, we analyzed the extract’s composition, revealing a rich presence of polyphenols and polysaccharides, with hesperidin, melitidin, and hesperetin as the predominant polyphenolic compounds. Additionally, the study elucidated the monosaccharide composition profile of polysaccharides in the extract. Furthermore, Finger Citron extract markedly suppressed the production of key inflammatory mediators, including TNF-α, IL-6, and NO. The inhibition of protein phosphorylation levels of inhibiting the mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) signaling was also observed, indicating that the anti-inflammatory effects of Finger Citron extract may involve the NF-κB and MAPK signaling pathway. Given these findings, Finger Citron extract has the potential to act as a natural product with anti-inflammatory activity.

High-pressure homogenization (HPH) is a promising non-thermal technology for improving fruit juice quality, but its impact on the complex flavor of Gonggan cloudy juice remains unclear. This study investigated the effects of HPH using E-nose, gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometrymass spectrometry (GC-O-MS). While HPH did not alter basic physicochemical properties including total soluble solids (TSS), titratable acidity (TA) and reducing sugar content, it reduced vitamin C (Vc) content. At 400 and 600 bar, HPH significantly increased total phenol content by up to 23.1% and soluble pectin content by 94.26% via cell wall disruption. HPH simplified the aroma profile, increasing the terpene proportion to 85% while reducing aldehydes by over 85%, and the dominant aroma compound changed from linalool to (+)-limonene. GC-O-MS and ROAV analysis identified decanal, decanol, beta-myrcene, and (+)-limonene as key markers and showed a reduction in key odorants (from 17 to 13-15). Treatment at 400 bar enhanced desirable citrus terpenoids, whereas 600 bar increased off-flavor compounds (e.g., D-carvone). Overall, HPH simplifies and intensifies the citrus character, with 400 bar identified as optimal for flavor enhancement, providing a scientific basis for targeted quality improvement in premium cloudy juices.

This study revealed that during frozen storage of sea bass, reactive carbonyl species from oxidized visceral lipids migrated into the muscle, inducing "lipid-protein co-oxidation." In viscera-containing (CV) samples, myofibrillar protein carbonyl content increased by 108.26%, Ca2+-ATPase activity decreased by 50.9%, and total sulfhydryl content declined by 13.44%. Visceral lipid oxidation also altered free amino acid profiles, elevating bitter-tasting histidine and lysine while reducing sweet proline and glycine, which was consistent with electronic tongue results showing enhanced umami but reduced sweetness. Volatile analysis indicated enriched hydrocarbons and aldehydes in CV group. Proteomics identified 140 differentially expressed proteins, mainly associated with immune and structural functions, with KEGG enrichment highlighting PPAR signaling and immune pathways. Notably, immune proteins exhibited pronounced degradation. This, combined with the breakdown of structural proteins, accelerated muscle quality deterioration.

This study aimed to investigate the bioactive compounds and evaluate the antioxidant and anti-inflammatory properties of juice prepared from whole pomelo fruits (WPJ). Methods: Total flavonoid content, naringin levels, and nutrient composition of WPJ were quantified over the storage period. Flavonoid profiling was conducted using LC–MS. Anti-inflammatory activity was assessed in vitro using LPS-stimulated RAW264.7 macrophages, where dose–response effects on nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) were measured. An in vivo phenol red–induced mouse model was used to evaluate the effects of WPJ on respiratory secretion and pulmonary inflammation, with analysis of MAPK/NF-κB signaling pathways. Results: WPJ exhibited a high total flavonoid content (950.68 ± 7.65 mg/100 g), dominated by hesperidin, tribuloside, baicalin, apigenin 7-O-neohesperidoside, hesperetin, neohesperidin dihydrochalcone, naringenin, naringin, jaceosidin, and pinocembrin. In vitro, WPJ pretreatment significantly reduced NO, IL-6, and TNF-α production in LPS-stimulated RAW264.7 cells in a dose-dependent manner. In vivo, WPJ promoted phenol red secretion in the respiratory tract and attenuated pulmonary inflammatory responses, partly through inhibition of MAPK/NF-κB signaling. Conclusion: The results demonstrate that WPJ is rich in diverse flavonoids and possesses potent anti-inflammatory activity both in vitro and in vivo. Its ability to suppress key inflammatory mediators and modulate respiratory tract responses suggests potential benefits for pulmonary health. These findings support the potential application of WPJ as a functional food for preventing or alleviating cough- and phlegm-related conditions.

Irradiation, as a non-thermal processing technology, can effectively improve the quality of dried foods. This study explored the effects of irradiation on flavonoids and volatile flavor compounds in Citri Grandis Exocarpium. The color parameters of Citri Grandis Exocarpium had no significant changes after different doses of irradiation. 11 key flavonoid metabolites in Citri Grandis Exocarpium were obtained by flavonoid-targeted metabolomics, and 9 key flavor-active volatile compounds were analyzed by HS-GC-IMS with the analysis of the relative odor activity values. Moreover, the metabolic pathways of irradiation-induced flavonoid and flavor remodeling in Citri Grandis Exocarpium were finally elaborated, and the irradiation treatments were associated with the pathways of flavonoid biosynthesis, flavone and flavonol biosynthesis, phenylpropanoid biosynthesis, and fatty acid metabolism. The findings could provide a theoretical and research foundation for the application and development of irradiation technology in dried foods, as well as for the enhancement of flavonoids and flavor compounds.

In this study, the structural characterization and hypolipidemic activity in vivo of finger citron polysaccharide (FCP) were investigated. The FCP consisted of [-> t)-Ara(f)-(1 ->], [-> 5)-Ara(f)-(1 ->], and [-> 4)-Gal(p)-UA-(1 ->] with the molecular weight of 46.35 KDa. FCP significantly decreased the levels of total cholesterol (TC), triglyceride (TG), low density cholesterol (LDL-C), phenylpropionate aminotransferase (ALT), and aspartate aminotransferase (AST) and increased the level of high density cholesterol (HDL-C) in the serum of mice (P < 0.05). Besides, FCP could significantly improve the antioxidant enzymes activities and decreased the liver lipid metabolism indexes (P < 0.05). AMPK/ACC and PPAR alpha/LXR alpha were used to investigate the hypolipidemic mechanism of FCP, which indicated that FCP could up-regulate the protein and gene levels of AMPK, acetyl-CoA carboxylase(ACC), PPAR alpha and LXR alpha. This study provides an important basis of FCP for inhibiting the occurrence of metabolic disorders such as hyperlipemia and complications.

Whole-fruit juicing represents a sustainable zero-waste approach for citrus processing, yet it introduces significant stability challenges due to the complex colloidal system. This study investigated high-pressure homogenization (HPH) as a physical intervention to stabilize whole-fruit Gonggan juice. Results demonstrated that HPH treatment above 200 bar significantly improved suspension stability by reducing particle size and increasing aggregation symmetry. Treatment at 400 bar/2 cycles yielded the most negative Zeta potential. HPH effectively released tightly bound pectin. Water-soluble pectin (WSP) content increased by 1.46 times, while chelate-soluble pectin (CSP) first rose then fell, and sodium carbonate-soluble pectin (NSP) remained stable. HPH increased RG-I branching , especially in WSP treated at 400 bar for 2 cycles ((Gal+Ara)/Rha ratio reached 28.70 ± 0.24). the Atomic force microscopy (AFM) revealed WSP backbone degradation under high pressure, while CSP and NSP chains exhibited enhanced aggregation. HPH promoted aggregation in high molecular weight pectins (CSP, NSP), with low molecular weight fragments likely converting to WSP. This study identified the appropriate HPH parameters for whole-fruit Gonggan juice, providing a scientific basis for optimizing this key processing step.

Fresh-cut lotus root is highly susceptible to quality deterioration, primarily due to enzymatic browning and microbial growth. This study investigated the efficacy and mechanism of 60Co-γ irradiation in preserving the quality of fresh-cut lotus root. The results demonstrated that irradiation effectively controlled total bacterial numbers within 5 log10 CFU/g throughout the storage period. Irradiation significantly inhibited browning, reducing the browning index by 19.6%, 25.3%, and 28.6% at 1, 2, and 3 kGy, respectively, compared to the control. This inhibitory effect was attributed to the delayed degradation of total phenolics and the suppressed accumulation of soluble quinones, the direct browning precursors. Irradiation induced a dose-dependent inhibition of polyphenol oxidase (PPO) activity, with the 3 kGy treatment exerting the strongest suppressive effect; however, the activities of phenylalanine ammonia-lyase (PAL) and peroxidase (POD) remained unaffected. Circular dichroism (CD) and fluorescence spectroscopy revealed three kGy irradiation induced rearrangements in the secondary structure, and disruption of the tertiary structure of PPO. Specifically, CD analysis definitively characterized conformational changes in PPO, showing a dramatic reduction in the α-helix content from 35.4% to 18.4%. Meanwhile, fluorescence spectra of PPO exhibited a 12 nm redshift accompanied by significant fluorescence quenching. This phenomenon provides direct evidence that the enzyme's tertiary structure was disrupted, which in turn lead to the exposure of its hydrophobic core and ultimately resulted in functional inactivation. 60Co-γ irradiation is a highly effective technology for maintaining the quality of fresh-cut lotus root, primarily through direct microbial inactivation and the suppression of the PPO-mediated browning pathway.

ObjectiveThis study aims to investigate the characteristics of protein components and the types of cloudy proteins in Tribute citrus turbid juice.MethodsProteomics was used to analyze the proteomic features of the supernatant proteins and precipitated proteins in Tribute citrus turbid juice.ResultsThere were significant differences in the electrophoresis bands of the supernatant proteins and precipitated proteins in Tribute citrus turbid juice. Compared with the supernatant proteins, precipitated proteins contained 2 897 differential proteins, including 2 487 up-regulated differential proteins and 410 down-regulated differential proteins. The up-regulated differential proteins in Tribute citrus turbid juice were mainly enriched in metabolic pathways including tyrosine metabolism, fatty acid degradation, and phagosome, mainly from cellular components such as chloroplasts, cytoplasm, and nucleus. Six types of cloudy proteins were screened from up-regulated differential proteins in Tribute citrus turbid juice, including one pathogenesis-related protein and five glycoproteins.ConclusionProteomics can be used to explore the protein differences in Tribute citrus turbid juice.

This study investigated three key stages of cold-chain logistics-chilling, supercooling, and freezing-to evaluate their effects on the physicochemical properties of squid (Uroteuthis edulis). During chilling, sulfhydryl groups showed increased oxidation and Ca2+-ATPase activity declined markedly in the later storage-stage. Proteomic analysis indicated that prolonged cold-chain duration led to original proteins cleavage, resulting in increased number of differentially expressed proteins (DEPs). Chilled group exhibited a greater number of altered Gene Ontology terms and DEPs than supercooled and frozen groups. Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated that higher storage temperatures activate apoptosis- and proteolysis-related pathways, thereby accelerating quality deterioration. Correlation analysis identified 61, 27, and 25 DEPs that were significantly associated with key quality indicators during chilling, supercooling, and freezing, respectively. This study clarifies the molecular mechanisms underlying squid quality deterioration and offers a theoretical basis for developing targeted preservation strategies and optimizing cold-chain process parameters.

This study developed nanostructured lipid carriers (NLCs) using edible beeswax and flaxseed oil to encapsulate β-sitosterol. Structural analysis revealed the formation of a less ordered lipid matrix with reduced crystallinity compared to pure beeswax, contributing to a high encapsulation efficiency of 92 %. Optimal formulation (beeswax: flaxseed oil 3:2, Tween 80: Polyglycerol fatty acid(PGE) 4:1 totaling 7 % emulsifier) and processing parameters (10 min homogenization, 200 W ultrasonic power for 4 min) yielded stable nanoparticles maintaining physical stability for 40 days across varying pH and temperature. In vitro digestion demonstrated that the NLCs effectively protected β-sitosterol from gastric degradation and enabled controlled intestinal release, achieving significantly higher bioaccessibility (43.9 %) compared to free β-sitosterol (12.1 %). These results highlight beeswax-flaxseed oil NLCs as a promising delivery system for enhancing the bioaccessibility of hydrophobic bioactive in functional foods.

Compared to conventional pharmacological therapies, xanthine oxidase (XO) inhibitory peptides offer a potentially safer approach for managing hyperuricemia. In this study, a good XO-inhibitory fraction was separated from chicken hemoglobin hydrolysate and 11 peptides were screened by in silico screening. Subsequent synthesis and activity validation revealed that three peptides, WPDNGFPGPQ, PPNSDIGWRV, and NGPAHW, significantly inhibited XO activity via non-competitive or mixed-type inhibition, with IC₅₀ values of 3.95, 4.85, and 6.39 mM, respectively. Molecular docking and dynamic simulations indicated that these peptides binded tightly to XO primarily through hydrogen bonding and hydrophobic interactions. Furthermore, optimization studies on WPDNGFPGPQ demonstrated that an optimal chain length is critical for effective XO inhibition, with the nonapeptide derivative (WPDNGFPGP) exhibiting the strongest activity. These findings suggest that chicken hemoglobin represents a promising natural source of bioactive peptides for the potential treatment of hyperuricemia.

Toxic compounds in fried food products attract increasing attention, but studies regarding the levels of common toxins, such as malondialdehyde (MDA), 4-hydroxy-2-hexenal (4-HHE), and 4-hydroxy-2-nonenal (4-HNE), in fried starch-based food (FSBF) are scarce. Herein, we investigated the formation and distributions of these aldehydes in FSBF, and the frying oil and FSBF retained higher levels of low-molecular-weight aldehydes. The highest aldehyde concentrations were observed in French fries. Simulated frying experiments revealed that the distributions of the toxic aldehydes in FSBF were mainly determined by the amylose content. Molecular dynamics simulations indicated that amylose interacted strongly with 4-HNE, but its interactions with MDA and 4-HHE were weaker. The migration of MDA, 4-HHE, and 4-HNE into FSBFs was primarily attributed to the interactions between the toxic aldehydes and amylose. This study should provide a novel basis for the control and elimination of toxic aldehydes in fried food.

A gold nanoparticle-based colorimetric assay was developed for patulin, a mycotoxin, detection in fruit juice. Eight patulin-specific aptamers were rigorously screened using molecular docking and specific binding analyses to select the optimal candidate. The optimized assay exhibited a wide linear detection range of 5.0–200.0 ng/mL in the buffer reaction system and high specificity for patulin. Its reliability for real-world samples was validated by achieving good recoveries (83.6

Alternaria alternata is a common fruit-decaying fungus that is potentially hazardous to fruit quality and human health. In this study, volatile and non-volatile compounds in cherry quality after artificial inoculation with A. alternata during cold storage were investigated using HS-GC-IMS and LC-MS. After fungal exposure, cherry samples exhibited significant changes in fungal counts, fruit firmness, and total soluble solid. A total of 36 volatile compounds, including 15 alcohols, 9 aldehydes, 5 esters, 4 ketones, 2 sulfur compounds, and 1 hydrocarbon were detected in the cherries by HS-GC-IMS. Changes in various aldehydes and sulfur compounds occurred in the early and middle storage stages, and changes in alcohols, esters, and ketones occurred in the middle-later storage stages. Seven types of non-volatile compounds were identified as key differential metabolites including 2-hydroxyphenylacetic acid O-b-D-glucoside, 2-O-benzoyl-D-glucose, gluconic acid, D-glucuronic acid, malonic acid, portulacaxanthin II, and altenusin, which are involved in the biosynthesis pathways of glucose, glycoside compounds, betalain, and fungal metabolites. This study provides further understanding of the relationship between the contamination of A. alternata and the quality of cherry fruit and lays the foundation for preservation technology for fresh fruit.

Fermented-litchi polysaccharide (Lzp) has been demonstrated to enhance the production of exopolysaccharides (EPS) in Weissella confusa in our previous study. To elucidate the underlying mechanisms, the resulting EPS was identified as a homopolysaccharide primarily composed of →6)-α-d-Glcp-(1→. Integrated metabolomics and transcriptomics analyses identified 19 differential metabolites and 60 differential genes associated with the effects of Lzp. Specifically, 13 extracellular metabolites were enriched in ABC transporters, starch and sucrose metabolism, and glycerophospholipid metabolism, while 6 intracellular metabolites were linked to aminoacyl-tRNA biosynthesis and pyrimidine metabolism. Transcriptomics revealed upregulation of key genes in the ABC transporter pathway (msmX, ugpA, ugpE, and pstS) and sucrose synthase-dependent pathway (sacA and sucA), facilitating the transport of EPS precursors and their extracellular assembly. Notably, Lzp-derived galactose and arabinose were transformed into UDP-glucose via the Leloir pathway and the pentose phosphate pathway, respectively, thus enhancing the availability of UDP-glucose for EPS synthesis. Validation via qRT-PCR confirmed the regulatory roles of these genes. Furthermore, genes involved in pyrimidine metabolism (pyrB, pyrE, etc.) were modulated to regulate nucleotide synthesis, indirectly supporting EPS polymerization. This study unveils Lzp's multi-target mechanism, coordinating carbohydrate metabolism, transporter activity, and transcriptional regulation to enhance EPS production, offering a foundation for industrial optimization using natural polysaccharides.