This study explored the influence of pressure on the flavor quality of the aqueous extract of Agaricus bisporus. By comparing the processes of boiling under normal pressure (BO) and boiling under high-pressure (PO), the effect of pressure differences on flavor substances was analyzed. The results showed that among the non-volatile flavor substances, the total free amino acids (66.79±0.05 mg/g), umami nucleotides (366.38±33.10 μg/g), and equivalent umami concentration value (10600.56±1370.38 mg MSG/G) in the BO group were significantly higher than those in the PO group (P<0.05), but the organic acid content was lower. Electronic tongue analysis further indicated that the BO group had more advantages in the response values of the sweet, salty, and astringent sensors. The analysis of volatile components showed that gas chromatography-mass spectrometry (GC-MS) identified 20 aroma substances in the BO group, mainly acids and alcohols, most of which had pleasant aroma characteristics. The PO group detected 30 substances, mainly aromatics and alkanes. Gas chromatography-ion mobility spectrometry (GC-IMS) detected a total of 28 volatile flavor components, among which the BO group had a higher richness of alcohols, aldehydes, and esters. Electronic nose confirmed that there were significant differences in the aroma profiles between the two boiling methods, indicating that boiling under normal pressure was more conducive to the formation of rich flavor characteristics. This study will provide a theoretical basis and technical support for the optimization of the deep processing technology of flavor substances in Agaricus bisporus and the development of high-value-added products.

This study investigated effect of adding serine, glutamic acid, or glycine to the "cysteine-xylose" system on formation of volatile flavor compounds via the Maillard reaction, aiming to provide guidance for meat animals breeding, meat food processing, and meat flavorings preparation. For the different Maillard reaction systems, their reaction extents were assessed by measurement of UV absorption at 294 and 420 nm, color difference values, pH, and the remaining xylose in the reaction solutions. Volatile flavor compounds generated were comparatively analyzed by solid-phase microextraction/gas chromatography-mass spectrometry (SPME/GC-MS) and aroma extract dilution analysis in gas chromatography-olfactometry (AEDA/GC-O) in combination with partial least squares regression (PLSR) analysis and odor activity value (OAV) calculation. The results showed that addition of each of the three amino acids in four times the molar concentration of cysteine, the reaction extents of the Maillard reaction systems were enhanced. Addition of glycine caused the most browning of the reaction solution, followed by that of serine and glutamic acid. On the other hand, formation of volatile flavor compounds also increased as well with addition of the three amino acids. Especially, addition of glutamic acid produced the highest amount of sulfur-containing meaty compounds, where the odor-active compounds of them had greater dilution factors and the key aroma compounds (OAV≥1) of them exhibited larger OAVs. As the three amino acids were increasingly added to "cysteine-xylose" system, amounts of sulfur-containing key aroma compounds generated in the reaction systems first rose then fell, whereas amounts of the pyrazine key aroma compounds ascended all the way. As serine and glutamic acid each were in four times cysteine concentration, and glycine was in two times cysteine concentration, the sulfur-containing key aroma compounds were maximally yielded in the reaction systems, respectively. In conclusion, among the three amino acids, glutamic acid caused the weakest browning reaction and benefitted generation of sulfur-containing meaty compounds.

Objective: To establish a multiplex real-time PCR assay capable of simultaneously and rapidly identifying bovine, chicken, duck and porcine components in beef products and thus to counteract economically motivated adulteration with cheaper meats. Methods: Species-specific primers and TaqMan probes targeting the mitochondrial cytochrome b (Cytb) gene were designed and screened for cattle, chicken, duck and pig. A single-tube reaction system was constructed and systematically validated for sensitivity, specificity, linearity and adulteration simulation. Results: The assay exclusively amplified DNA from cattle, chicken, duck and pig, with no cross-reactivity against 6 non-target species. The method simultaneously detected four animal-derived DNA with 10⁻⁴ ng/μL sensitivity and a 0.01% (w/w) detection limit. Screening of 100 retail beef samples revealed 24 adulterated products, predominantly containing duck meat and/or pork. All results were fully concordant with those obtained by the national standard method. Conclusion: The developed multiplex real-time PCR protocol is rapid, cost-effective and high-throughput, significantly enhancing the capability to detect meat adulteration and providing robust technical support for food-safety regulation and consumer protection.

The effects of 200 W (UC200), 300 W (UC300) and 400 W (UC400) ultrasound assisted vinasse-curing on the formation of characteristic flavor in vinasse-cured beef were studied using beef as the fresh raw materials. The sensory quality, structure and morphology of myofibrillar proteins, fingerprint and odor-active values of volatile compounds were investigated to reveal the changes of ultrasound assisted vinasse-curing on the conformation of myofibrillar proteins and characteristic flavor in vinasse-cured beef. The correlation analysis was further employed to identify the correlation between the changes of myofibrillar proteins and the formation of characteristic flavor in vinasse-cured beef. The results demonstrated that 200 W (UC200), 300 W (UC300) and 400 W (UC400) ultrasound assisted vinasse-curing were able to improve flavor quality of vinasse-cured beef. Specifically, the ester aroma scores in the UC200, UC300, and UC400 groups increased from 0.50 in the control group (CK) and 6.25 in the non-ultrasonic fermentation group (NUC) to 7.23, 8.00, and 7.02, respectively (P<0.05), with the UC300 group showing a higher score than the UC200 and UC400 groups. Conformation analysis revealed that, the UC300 group exhibited the highest intrinsic fluorescence intensity and surface hydrophobicity of myofibrillar proteins compared to other groups, reaching 2293.55 and 22.54 μg, respectively. Meanwhile, its α-helix content, average particle size, and surface roughness were the lowest, at 24.91%, 1.64 μm, and 0.43 nm, respectively. SPME-GC-MS results showed that a total of 43 volatile compounds were identified in the vinasse-cured beef. Esters, aldehydes, and alcohols accounted for 75.96% of the total flavor compound content. The ester compounds content of UC300 group increased from 50.18 mg/kg of NUC group to 58.53 mg/kg (P<0.05). Partial least squares regression analysis and odor-active values indicated that ethyl caprylate, ethyl decanoate, phenethyl acetate, phenylacetaldehyde, nonanal, ethyl valerate, ethyl butyrate, ethyl benzoate, ethyl nonanoate, and ethyl phenylacetate were the key odor-active substances responsible for the increased characteristic flavor in the UC300 group. Spearman correlation analysis indicated that key odor-active compounds such as ethyl valerate and ethyl benzoate were negatively correlated with the α-helix of myofibrillar proteins, and positively correlated with the ester and alcohol aroma. Therefore, this research can provide critical references for the application of ultrasound in improving the aroma quality of vinasse-cured meat products.

An integrated strategy that combining untargeted metabolomics based on ultrahigh performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS), targeted amino acid analysis and chemometrics was developed to achieve the metabolic profiling analysis of different parts (pileus and stipe) of Pholiota adiposa fruiting body. The HRMS data of Pholiota adiposa were acquired in positive ion mode and directly analyze by AntDAS-DDA, a recently developed automatic data analysis software in chemometrics. In addition, the contents of 16 free amino acids in the samples were quantified according to the national standard methods. The metabolomics characteristics across different parts of the Pholiota adiposa fruiting body were investigated using heatmap analysis, radar chart analysis, hierarchical cluster analysis (HCA) and principal component analysis (PCA). The results indicated that a total of 73 involatile differential metabolites were identified, encompassing amino acids, nucleotides, purines, alkaloids, terpenoids, lipids, etc., 12 of those compounds were further verified by standards. Except for tryptophan, which was more abundant in the stipe, contents of lysine, histidine, arginine, tyrosine, phenylalanine, vitamin B5, and vitamin B2 were consistently slightly higher in the pileus than in stipe. Nucleotides such as adenosine and guanosine, along with purines like guanine and hypoxanthine, also showed higher content in the pileus. Umami amino acids were the most abundant category across all parts of the Pholiota adiposa fruiting body, constituting over 30% of the total free amino acids. Notably, the content of umami amino acids in the pileus was significantly higher than in the stipe. the pileus, stipe and whole fruiting body of Pholiota adiposa could each be clearly clustered and distinguished. This research provides a scientific basis for the identification of nutritional characteristics and resource utilization of different parts of Pholiota adiposa, while offering a novel analytical strategy for studying chemical components in other edible fungi.

The characteristic flavor compounds in five types of sour bamboo shoots from northern Guangdong were analyzed using ultrasonic assisted solvent extraction-gas chromatography-mass spectrometry (UASE-GC-MS), odor activity value (OAV), and the 3-AFC method. Principal component analysis (PCA) was applied to compare differences among fermentation processes. A total of 78 volatile compounds were detected, including 16 alcohols, 7 phenols, 9 aldehydes, among others. Thresholds were determined for 14 compounds using the 3-AFC method, and their OAVs were calculated. Sixteen compounds had OAVs ≥ 1, among which p-cresol (The highest OAV among the five samples was 20951.30, and the lowest was 2153.03), decanal (The highest OAV among the five samples was 241.44, and the lowest was 45.40), and 1-octen-3-one (The highest OAV among the five samples was 1958.36, and the lowest was 614.59) showed the highest OAVs and were identified as key flavor compounds. PCA indicated that the sample fermented in large tanks (SGNX-D) had the highest total flavor content (7264.74 μg/g), with its distinctive flavor associated with compounds such as ethyl palmitate, decanal, and phenol. Moreover, this study revealed for the first time the essential role of decanal (highest OAV among aldehydes) and ethyl cinnamate (only ester with OAV > 10) in enhancing the complexity of the flavor profile of sour bamboo shoots.

To investigate the effect of Weissella jogaejeotgali SL7 (W.jogaejeotgali SL7) on the quality and flavor of fermented sausage, fermented sausage without SL7 was used as the control group. The dynamic changes and differences in physicochemical properties (pH, moisture content, water activity), total bacterial count, nitrite content, peroxide value, thiobarbituric acid (TBARS), carbonyl, sulfhydryl groups, and volatile flavor compounds during the fermentation process were analyzed. The results showed that the pH, moisture content, water activity (a_w), and total bacterial count of fermented sausage with W. jogaejeotgali SL7 added were significantly (P<0.05) lower than those of the control group (CK), and the nitrite content (1.71 mg/kg) was significantly (P<0.05) lower than that of the CK group. The peroxide value (POV), TBARS, and carbonyl content of W. jogaejeotgali SL7 fermented sausage were significantly (P<0.05) lower than those of the CK group, while the total sulfhydryl content was significantly (P<0.05) higher than that of the CK group. The HS-SPEM-GC/MS method was used to determine the content of volatile flavor compounds in W. jogaejeotgali SL group, which was 7668.93 µg/kg, including 89 types of volatile flavor compounds such as alcohols, terpenes, aldehydes, and ketones. The quantity was much higher than that of other groups. Adding W. jogaejeotgali SL7 to fermented sausage can significantly reduce its nitrite content, effectively inhibited fat and protein oxidation, and promote the formation of flavor compounds.

To investigate the effects of different manufacturing processes on the quality formation of Huangshan Maofeng tea, fresh leaves (one bud and one leaf) from the tea cultivar 'Wancha 4' (Camellia sinensis var. sinensis) were processed into five types of green tea using distinct manufacturing processes. These included striping fixation at 230 ℃ coupled with striping shaping process (L), rotary fixation at 400 ℃ coupled with striping shaping process (GL), rotary fixation at 400 ℃ followed by rolling and then striping shaping (GRL), rotary fixation at 340 ℃ coupled with striping shaping process (G2L), and rotary fixation at 340 ℃ followed by rolling and then striping shaping (G2RL). A systematic study was conducted on the quality characteristics and differences in metabolite profiles of five types of Huangshan Maofeng tea by sensory evaluation, metabolomics and multivariate statistical analysis. Sensory evaluation results indicated that GL achieved the highest overall quality, followed by GRL, both exhibiting superior refreshing aroma and mellow, umami tastes. Metabolite analysis revealed that the total free amino acids contents in GL and GRL reached 63.34±0.80 mg/g and 65.21±0.47 mg/g, respectively, which were significantly higher than those in others. In contrast, metabolites contributing to bitterness and astringency, such as caffeine, proanthocyanidins, flavonoid glycosides, and phenolic acids, were lowly concentrated in GL and GRL. Volatile analysis revealed that a total of 44 aroma components were identified in five types of Huangshan Maofeng tea. Among them, alcohols were major volatile classes (28%~49%). 11 differential compounds (VIP value>1, P<0.05) were identified by partial least squares discriminant analysis, including dimethyl sulfide, geraniol, benzyl alcohol, phenylethyl alcohol, (Z)-3-hexen-1-ol, etc. Notably, the content of dimethyl sulfide with corn-like and sweet flavor was significantly higher in GL and GRL, which could be the critical factor leading to their prominent aroma quality. This study provides a theoretical basis for the high-quality production of Huangshan Maofeng tea.

Hemerocallis citrina Baroni (daylily) is a medicinal and edible food with flavonoids as its core active ingredient. Daylily showed significant differences in flavonoids across varieties, thereby impacting their health benefits. This study selected four daylily varieties in the Datong, namely Datong (DT), Mallian (ML), Mengzi (MZ), and Huaiyang (HY), for metabolomics to unravel their flavonoid composition. DT exhibited the highest total flavonoid content (TFC), while MZ demonstrated the strongest antioxidant potential. There were ten highly differential flavonoid metabolites in four daylily varieties that had a significant positive correlation with their antioxidant activity. Notably, the levels of these metabolites in MZ were the highest, corresponding to its strongest antioxidant activity. Network pharmacology analysis revealed that antioxidant targets associated with key flavonoids in daylily were primarily focused on PI3K-AKT signaling pathway, identifying AKT1 and EGFR as the core antioxidant targets. Molecular docking results demonstrated their interaction mechanisms, suggesting that daylily flavonoids might attenuate the oxidative stress. This research provides critical insights for selecting and cultivating daylilies with enhanced health benefits.

This study examined the effect of various packages on the quality and shelf-life of purple sweet corn stored at ambient temperature, providing a theoretical foundation for the e-commerce logistics and shelf-life sales of purple sweet corn. Fresh purple sweet corn was harvested and packaged using three methods: commercial low-density polyethylene bags (CK), MP30 spontaneous modified atmosphere packaging bags (MP30), and MP30+PVA double-layer composite bags (MP30+PVA). All packaged samples were stored at 25±1 ℃ and 80%±5% relative humidity. The changes in internal gas concentration in different bags, and quality of sweet corn were monitored and analyzed during storage. The results showed that both MP30 and MP30+PVA effectively modified the storage microenvironment, establishing a low-O₂ and high-CO₂ atmosphere within the five days of storage. The color difference values (L^*, a^*, and b^*) of husk leaves increased by 5%~14%, with ΔE values reaching 24.29% and 29.17% of the CK group, respectively, delaying the husk yellowing. On the 5th day of storage, the respiration intensity of the MP30 and MP30+PVA groups decreased by 25.59% and 12.13%, respectively. Compared to CK, the weight loss rate decreased by 26.65% and 36.54%, respectively. Additionally, the reduction in the total soluble solids content in the two treatment groups was 23.71% and 20.78% lower than that of the CK group, respectively. Meanwhile, vitamin C content increased by 93.58% and 126.68%, and anthocyanin content exhibited a slight upward trend. Most measured indices showed no significant difference between MP30 and MP30+PVA, though MP30 offered greater cost efficiency. In conclusion, MP30 spontaneous modified atmosphere packaging extends the freshness of purple sweet corn to five days at room temperature while effectively preserving its sensory and nutritional quality. These findings provide a practical solution for room-temperature e-commerce logistics and shelf-life management of fresh sweet corn.