Abstract:With the application of physiological and multi-omics technologies, they will be able to accurately analyse the mechanisms of salt tolerance and fermentation promotion of fermentation microorganisms under salt stress, which will lay the foundation for the effective regulation of salt brine fermentation and enhancement of the flavour of traditional fermented foods. The article reviews the common salt-tolerant microorganisms in fermented foods, the main salt-tolerant mechanisms, the fermentation-promoting properties in high-salt environments, and the methods to study the salt-tolerant and fermentation-promoting mechanisms, as well as the future direction of their development.

Abstract:[Objective] In order to explore the loss pattern of V_C in kiwifruit pork jerky by twin-screw extrusion and solve the "black box" problem of nutrient loss during the extrusion process. [Methods] In this paper, a twin-screw extruder was used to produce kiwifruit pork jerky, and the V_C content of the material before and after extrusion was determined by high performance liquid chromatography, and the Mean Residence Time （MRT） was used as the reaction time of the material in the barrel, and the V_C loss rate under different extrusion conditions was dynamically analyzed. [Results] Increasing the temperature and moisture content of the barrel, decreasing the screw speed, and increasing the amount of dried fruit added during the extrusion process will increase the V_C loss rate of the extruded material. The variation pattern of MRT and V_C loss rate is basically consistent. Dynamic analysis shows that V_C loss during the extrusion process follows a first-order dynamic model, and the V_C loss rate constant is between 0.003 54 and 0.006 05 s^-1. [Conclusion] MRT is an important factor affecting the variation of V_C loss rate. A predictive model for V_C loss rate can be obtained through multiple regression analysis, which can achieve reasonable prediction of the variation pattern of V_C loss rate under different conditions and reduce production costs.

Abstract:[Objective] This study aimed to explore the mechanism of action between Amomum villosum polysaccharide (AVP) and wheat starch and reveal the dose-effect relationship of AVP on the quality of wheat starch. [Methods] an AVP-wheat starch compound system with different concentrations of AVP was prepared. The effects of different concentrations of AVP on the gelatinization characteristics, rheological properties, thermodynamic properties, crystal structure and digestion characteristics of wheat starch were studied. [Results] The AVP could increase the viscosity and gelatinization temperature of the wheat starch compound system, reduce the leaching of amylose during gelatinization and the damage degree of the crystalline region during wheat starch gelatinization, and delay the gelatinization process. When the concentration of AVP was 1.00%, the disintegration value of the compound system was 299 mPa·s, the retrogradation value was 532 mPa·s, and the gelatinization enthalpy was 666.29 J/g, indicating that the anti-aging effect and the stability were the best. Fourier infrared spectrum analysis showed that there was a hydrogen bond interaction between AVP and wheat, and the bond was the strongest when the mass concentration of AVP was 1.00%. The results of in vitro simulated digestion showed that AVP could inhibit the digestion of wheat starch. [Conclusion] Adding AVP can effectively improve the thermal stability of wheat starch and reduce the digestibility of wheat starch.

Abstract:[Objective] This study aimed to establish a preparation process for starch-lipid complex with high resistant starch （RS） content and to explore the effects of process parameters on the anti-digestibility of the complex. [Methods] Using RS content as the indicator, one-way experimental and orthogonal designs were employed to study the effects of temperature and time parameters during the pretreatment of high amylose corn starch （HA） and its complexation with stearic acid （SA）. The physicochemical properties, anti-digestibility, and hydration characteristics of the HA-SA complex prepared by the optimal process were analyzed. [Results] Increasing pretreatment temperature in the gelatinization temperature range, prolonging the pre-treatment time, and complexing temperature above 75 ℃ all led to a significant decrease in RS content of HA-SA （P＜0.05）. The optimal process was as following: HA being pretreated at an annealing temperature of 85 ℃ for 12 h, and then complexed with SA at 75 ℃ for 90 min. The prepared HA-SA showed the V-type crystalline pattern and entire starch granules shape, and was characterized as the type I complex. It also presented the significantly enhanced thermal stability, bettered anti-digestibility, and lowered swelling power than HA （P＜0.05）. [Conclusion] Annealing temperature pretreatment and optimal complexation temperature favored to prepare the starch-lipid complex with higher anti-digestibility and entire granule structure. Excessive thermal strength during pretreatment causing excessive gelatinization could impede the formation of RS in the complexes. And a complexation temperature over 75 ℃ led to the disassociation of the complexation, decreasing the RS content. Annealing pretreatment preserved the entire starch granule of HA, which was one of the reasons for the higher digestibility of HA-SA.

Abstract:[Objective] To realize rapid detection of green tea species identification. [Methods] A rapid detection method based on the combination of electronic tongue and electronic nose combined with CNN-Transformer composite model was proposed. The electronic tongue and electronic nose were used to collect the fingerprint information of taste and smell for five different kinds of green tea. The one-dimensional electronic tongue and electronic nose signals were transformed into two-dimensional time-frequency maps using the short-time Fourier transform （STFT）, which fully revealed the distribution characteristics of the signal energy in the time-frequency domain. A CNN-Transformer combination model was proposed to realize the fusion of the electronic tongue and the electronic nose information and pattern recognition. The model adopted selective kernel convolution and normalized attention in designing convolution module to replace the convolution layer of the traditional CNN to achieve the dynamic extraction of local features from the time-frequency map of the signal. The multi-head self-attention mechanism in the Transformer encoder was used to extract the global temporal information in the features of the electronic tongue and the electronic nose and achieve the weighted fusion of their features. Finally, classification recognition was carried out by the fully connected layer. [Results] The information fusion method based on electronic tongue and electronic nose could effectively extract the deep features of the taste and smell signals from green tea samples and provide richer fused feature representations for the model to achieve highly accurate recognition of different species, with a test set accuracy, precision, recall and F₁-Score of 99.00%, 99.05%, 99.00%, and 99.00%, respectively. [Conclusion] This study provides a low-cost, fast and efficient detection method for green tea species recognition.

Abstract:[Objective] To analyze the differences in volatile components between three kinds of dried L. edoeds. [Methods] Three different drying methods (hot air drying, radio frequency-hot air drying, vacuum freeze drying) were used to determine the volatile substances in L. edoeds by gas chromatogi-ion migration spectrometry (GC-IMS), and the differences of volatile substances in L. edoeds were analyzed according to fingerprint and PCA. [Results] The main volatile components of dried L. edoeds were aldehydes, alcohols, ketones and acids. There were significant differences in the characteristic volatile organic substances of dried L. edoeds in three different drying methods, the contents of aldehyde and alcohol were hot air drying > radio frequency-hot air drying > VD. Fingerprint analysis showed that compared with vacuum freeze drying, hot air drying and radio frequency-hot air drying could significantly improve the fruity flavor of L. edoeds. PCA analysis showed that the contribution rate of PC1 and PC2 was 61% and 29%, respectively, and the cumulative contribution rate reached 90.0%. Hot air drying and radio frequency-hot air drying had high similarity in the flavor composition of L. edoeds. [Conclusion] GC-IMS can realize differential and rapid analysis and identification of volatile flavor components of L. edoeds produced by three drying methods, and provide theoretical reference for high-quality drying of L. edoeds and its product identification.

Abstract:[Objective] This study aimed to screen the excellent lactic acid bacteria strains to construct a special pickle fermentation strain for radish. [Methods] Lactic acid bacteria were isolated from the pickle brines of Laotan sauerkraut collected from different regions by dilution coating method. The species were determined by physiological identification, morphological identification （colony observation, Gram staining）, 16S rDNA gene sequencing and phylogenetic tree construction, and their growth characteristics, tolerance and flavor substances were detected. [Results] Isolation, screening, and physiological identification yielded 120 colonies of round, convex bacteria, which appeared rod-shaped or spherical under the microscope and were all Gram-positive strains. Further 15 strains with high acid production capacity were obtained by acid production capacity test. By molecular sequencing, 1 strain was identified as Bacillus, 13 strains as Lactobacillus plantarum and 1 strain as Pediococcus pentosus. Among them, L. plantarum was the dominant lactic acid fermentation strain screened in Sichuan, Chongqing, Liaoning, Guizhou, Hunan and Nanping of Hubei province, and Bacillus and P. pentosus were screened in Tuanbao area of northern Hubei Province. The growth characteristics of different types of fermentation strains were analyzed, and the growth rate of strains LA-8 and LA-11 was faster than other strains; Strain LA-8 had the highest acid production capacity, and was resistant to 10% salt and 15% sucrose. All four strains had the ability to degrade nitrite. Strains LA-4 and LA-6 were able to produce 15% sucrose, and their growth rate and acid-producing capacity were slightly lower than that of L. plantarum. The initial experiment of radish fermentation showed that LA-8 and LA-11 had stronger fermentation ability and faster acid production. The electronic nose detection technology was used to detect the fermentation flavor of radish, and it was found that the volatile substances produced by four strains of different types of lactic acid bacteria were different. [Conclusion] Three different types of dominant fermentation strains were screened from the mother water of radish laotan pickle in different regions, which could be further used as the source of strains for the production of radish pickle industry.

Abstract:[Objective] In order to solve the issue of excessive redundant information in near-infrared spectroscopy, enhance the accuracy of wine quality evaluation models, a rapid and non-destructive method was established for wine quality evaluation. [Methods] A wine quality evaluation model was proposed based on competitive adaptive reweighting sampling method for feature wavelength screening and extreme learning machine improved by whale optimization algorithm. Various feature wavelength screening methods such as competitive adaptive reweighting sampling was used, and the most suitable method for wine spectral feature wavelength screening was determined. In response to the problem of initial value and hidden layer bias in ELM, the whale optimization method was used to optimize the initial value and hidden layer bias of ELM, and an wine quality evaluation model based on extreme learning machine improved by whale optimization algorithm was constructed. [Results] Compared with GA-ELM, PSO-ELM, and the traditional ELM model, the accuracy of WOA-ELM was the highest, reaching 0.944 5, which was better than GA-ELM (0.929 0), PSO-ELM (0.906 1) and traditional ELM (0.817 7). [Conclusion] The parameters of the ELM model optimized by intelligent algorithms can effectively improve the accuracy of wine quality evaluation.

Abstract:[Objective] Achieving a rapid, sensitive, and visual detection of 6-benzylaminopurine （6-BA） residues in vegetables. [Methods] Based on the peroxidase-like activity and specific recognition of Fe₃O₄ magnetic molecularly imprinted nanoparticles （Fe₃O₄ MMIP NPs）, a simple, rapid and highly selective colorimetric method was established to detect 6-BA residues in vegetables. [Results] Fe₃O₄ MMIP NPs exhibits optimal peroxidase-like catalytic activity at pH 4.0, 0.02 mol/L TMB, 0.02 mol/L H₂O₂ and a reaction time of 5 min. 6-BA showed a good linear relationship with the difference between the blank and the sample absorbance value in the mass concentration range of 1~300 ng/mL with a limit of detection at 0.697 ng/mL. The method was successfully applied to the detection of 6-BA residues in vegetables （cucumber, tomato, bean sprouts, mung bean sprouts）. The recovery rate was 83.47%~106.76%, with a relative standard deviation of 0.37%~5.66%. In addition, Fe₃O₄ MMIP NPs could still maintain good catalytic activity after 60 days of storage at 4 ℃. [Conclusion] The colorimetric method for the detection of 6-BA based on Fe₃O₄ MMIP NPs has the advantages of simplicity, rapidity, economy, and can be used for the detection of 6-BA residues in vegetables, which has certain reliability and practicability.

Abstract:[Objective] To achieve good internal quality control of determination of decamethylammonium chloride and benzalkonium chloride residues in drinking water by high performance liquid chromatography tandem mass spectrometry, and to promote the improvement of detection methods. [Methods] A mathematical model and fishbone diagram were established to evaluate the introduced uncertainty components, and the combined standard uncertainty and expanded uncertainty were calculated. [Results] Under the inclusion factor k=2, and the decamethylammonium chloride and benzalkonium chloride residue in drinking water samples was 4.3 μg/L and 4.7 μg/L and their expanded uncertainty U was 0.52 μg/L and 0.48 μg/L, respectively. [Conclusion] The uncertainty in determining the two disinfectants with high performance liquid chromatography tandem mass spectrometry mainly comes from the preparation of the series standard solutions, determination repeatability, and instrument calibration, etc.

Abstract:[Objective] To deal the technical difficulties in further realizing the automation of de nucleating production of fresh peach slices. [Methods] A new type of fresh peach slicing and coining machine was designed. The cutting tool for slice kerning was simplified and analyzed by Mathematical analysis, and the motion characteristic equation and curve of the mechanism were obtained. The motion simulation analysis of the slicing and core-removing tool mechanism was carried out by using SolidWorks Motion software, and the motion characteristic curve of the mechanism was obtained.The correctness of the mathematical analysis was verified, and the rationality of the design of the cutting tool was also verified. [Results] The machine uses PLC control, including fresh peach conveyor chain feeding, fresh peach positioning, slicing tool movement, etc. Through the analysis of the field test results, the average cutting rate of fresh peach slicing and coiling machine reached 99.39%, the average coiling rate reached 99.15%, and the average breakage rate was lower than 0.12%. [Conclusion] The new type of fresh peach slicing and coiling machine can realize the automatic positioning, cutting and coiling of fresh peach, etc.

Abstract:[Objective] To improve the design efficiency of the mechanical structure of the rotor system of a rubber roller husker. [Methods] An auxiliary calculation system for the rotor system design parameters of a rubber roller husker （RRHRSPD） that can be independently installed and operated under the Windows system was developed using VB and Matlab platforms. Based on the equivalent design method and the traditional mechanical design method, the coupling relationships among the technological parameters, dynamic parameters and structural parameters of the husker were established, and the calculation principle of the structural parameters of the rotor system was also explored. VB was used to develop the software operation interface and to quickly call the Matlab dynamic link library, which formed the core computing mechanism of the system, and the system was packaged and released. [Results] A set of auxiliary calculation system for structural parameters of the rotor system of rubber roller husker was developed. [Conclusion] The calculation results of the system are accurate and reliable, which can be used not only for the design and calculation of the rotor system structure of the rubber roller husker, but also for the virtual test platform for the performance analysis of the rubber roller husker.

Abstract:[Objective] To solve the problem of poor manual detection accuracy of traditional grain and chaff separator and improve production efficiency. [Methods] An image detection method based on machine vision was proposed, which realized the feature recognition and separation of grain rough through multi-stage progressive fusion of different image algorithms. The acquired images were selected in the ROI region and enhanced by Retinex algorithm. The Otsu algorithm was used to segment the image, and then the median filtering wwas combined with morphology to remove the image noise. The improved Canny algorithm was used to detect edge features of binary images, and the position information of the contour of the valley rough image was extracted by combining the Hough transform. Finally, the state estimation of the position information was performed by using the Kalman filter, and the best predicted value of the separated position was obtained, while the position offset error was reduced. [Results] The average detection error of the system was 3.14 mm, a decrease of 1.82 mm compared to before filtering, and the average standard deviation of filtering error was 0.8 mm. [Conclusion] This method can effectively detect the grain rough feature information and improve the separation accuracy.

Abstract:In response to the current situation of packaging design for local food, this study extracts structural features, decorative element features, color features, and cultural features from spatial art based on Meishan culture, and deconstructs them into local food packaging design. It explores the design ideas and strategies of integrating the spatial artistic essence contained in Meishan culture with local food packaging, enhancing food-added value, showcasing regional characteristics, enhancing cultural connotations, assisting local economic development and cultural dissemination, promoting the inheritance of ethnic culture, and innovating local food packaging.

Abstract:The paper summarizes and analyzes the progress of research on the use of intangible cultural heritage in food packaging design through the number of articles, keywords, research objects, research perspectives and ideas. The study analyzes the application of intangible cultural heritage in food packaging design from three aspects: principles, strategies, and methods. It also explores the future development directions, suggesting that future research can guide design practice through theoretical studies and validate design practice using big data models.

Abstract:[Objective] This study aimed to reveal the reasons of different varieties for sweet cherry's storability and provide theoretical support and technical guidance for edible coating in its postharvest preservation. [Methods] Four representative sweet cherry varieties （Red Light, Rainey, Red Agate, and Friendship） were selected as research objects. The surface morphology of different varieties of sweet cherry skin, the contact angle of skin to different solutions, the changes of surface morphology, contact angle and critical surface tension of Red Agate sweet cherry during storage were investigated. [Results] There were differences in the distribution and morphology of wax on the epidermal of the four varieties of sweet cherry, and the contact angle of the skin to the same solution was significantly different. The wax content of the Red Agate epidermis decreased during storage. Due to the hydrophobicity of sweet cherry skin, adding Tween-20 as a surfactant to the coating liquid can significantly improve its surface wettability. The contact angle of the Red Agate epidermis to deionized water decreased during storage, and the critical surface tension increased with the extension of storage time. [Conclusion] The storability of different varieties of sweet cherries may be correlated with their skin characteristics. Adding 0.1% Tween-20 to the coating solution can make the solution more evenly coated on the surface of the sweet cherry.

Abstract:[Objective] To improve the accuracy of online measurement of sugar content of grapefruit by near infrared spectroscopy. [Methods] The pomelo online non-destructive testing equipment developed by ourselves was used to collect diffuse transmission spectrum data of pomelo in three light regions. In the wavelength range of 650~950 nm, orthonormal variable transformation （SNV）, multiple scattering correction （MSC）, Normalize, Savitzky-Golay first order derivative, SG-1st preprocessed the original data, used the adaptive weighting algorithm （CARS） to screen the spectral characteristics of the grapefruit sugar content, and established a partial least squares regression （PLSR） model. 30 grapefruit samples that were not involved in the modeling were used for online verification. [Results] The modeling effect of light region C combined with SNV-CARS-PLSR method was the best. The coefficient of determination of the prediction set was 0.95 and the root-mean-square error was 0.30 °Brix. In online verification, the coefficient of determination was 0.90 and the root mean square error was 0.58 °Brix. The model had a strong ability to detect the sugar content of grapefruit on line. [Conclusion] The prediction model based on the spectral data collected under the condition that the light spot diameter is 70 mm and the light region C is 20 mm above the equator of the grapefruit can realize the online prediction of the sugar content of the grapefruit more effectively.

Abstract:[Objective] Refining the accuracy and intelligence of passion fruit quality assessment. [Methods] The study used the capabilities of OpenCV along with a compact neural network architecture, MobileNetV3_large_ssld, to accurately determine the fruit's diameter, ripeness, and the degree of its wrinkling. The diameter measurement was achieved by analyzing the short side of the fruit's minimum bounding rectangle. The ripeness assessment was based on the pixel ratio of H component values within specific ranges （H∈[0,10]∪[156,180], [11,25], [26,34], [125,155]） in the HSV color space. Furthermore, the study developed a MobileNetV3_large_ssld model to evaluate the wrinkling of the fruit's skin. Leveraging these three key indicators, a comprehensive fruit quality evaluation model was established using a rating scale approach, and an online detection and sorting system was subsequently developed. This system employed KNN background subtraction to extract the fruits target, excludes stems, and used interval frame sampling method to capture single image for each fruit from the video. The comprehensive evaluation model was utilized to assess the quality of passion fruits, which were then sorted into their appropriate grade channels through a sorting mechanism. [Results] The test results indicated a high degree of consistency between the system's sorting and manual sorting, with an overall accuracy of 97.02%. The consistency rates for top-grade fruits, first-grade, and second-grade fruits were 95.51%, 97.84%, and 100%, respectively. [Conclusion] This system could be used for online detection and sorting of passion in different quality grades.

Abstract:[Objective] To meet the practical requirements for comprehensive grading based on the appearance quality and size of apples, and to address issues such as low efficiency of manual sorting, complex structure, and high cost of sorting equipment for Chinese apples. [Methods] A YOLOv5s-apple model was proposed. The transformer module and CBAM attention module were introduced into the backbone network, and the weighted Bidirectional feature pyramid network (Bi-FPN) was added to improve the neck network. Then, combined with HALCON software, a self-designed intelligent apple damage detection system was used to carry out damage sorting and size classification. [Results] The experimental results showed that compared with the original YOLOv5s model, the mAP of the YOLOv5s-Apple model was improved by 6.2%, and the accuracy of apple sorting system could reach 97.5%, the processing speed of the system was 5 s/apple. [Conclusion] The system can effectively carry out apple grading and sorting, and provide a reference for the intellectualization and low cost of Apple detection equipment.

Abstract:[Objective] To improve the detection accuracy of early apple spoilage zone. [Methods] An apple spoilage detection method was proposed based on generative adversarial network and convolutional neural network. The Pix2PixHD model was used to generate near-infrared imaging data of stored apples in the early postharvest metamorphic area. The Mask R-CNN model was used to segment the generated near Infrared image to detect the deterioration zone in the apple. Based on generative adversarial network and convolutional neural network technology, the early deterioration region segmentation and prediction of postharvest apples were implemented by using the generated near-infrared imaging data on a low-cost embedded system with artificial intelligence function. [Results] The average accuracy of this method was 1.825%～10.435% higher than that of the other nine methods. The Pix2PixHD generated a visible NIR image from an RGB image at 17 frames per second, and the Mask R-CNN was able to segment spoilage areas in an apple image at 4.2 frames per second. [Conclusion] The proposed method is expected to facilitate the development of low-cost food quality controllers.

Abstract:[Objective] In order to study the effects of geosynclinal ventilation on the temperature of tall bungalow warehouse. [Methods] The numerical simulation software COMSOL was used to conduct numerical simulation of temperature field under mechanical ventilation for 96 h for tall bungalow warehouse with size of 60 m×24 m and loading height of 6 m. By establishing the mass conservation equation, momentum conservation equation and energy conservation equation, the variation of temperature field in the warehouse under different ventilation modes was analyzed, and the numerical simulation of different unit ventilation conditions was extended. [Results] After mechanical ventilation for 36 h, most of the grain pile below the grain line in the warehouse had dropped to 15 ℃, and after mechanical ventilation for 96 h, the temperature of the grain pile had dropped to below 15 ℃, the grain layer temperature at the distance of 1~6 m from the bottom of the warehouse all dropped below 15.2 ℃. By changing the unit ventilation rate [q=3 m³/(h·t) to q=8 m³/(h·t)], the cooling rate of the grain pile became faster. [Conclusion] The temperature of the grain pile decreases gradually from the bottom of the bin and spreads in an arc shape under the geosynclinal ventilation condition. The grain layer 1 m and 2 m away from the bottom of the warehouse is affected by the fluctuation of external environment temperature, and the temperature gradually decreased in the fluctuation. With the increase of the distance between the grain layer and the bottom of the warehouse, the temperature fluctuation gradually disappears. The temperature change of grain pile in the bin appears a certain lag, and the cooling rate of grain layer temperature decreases with the increasing distance from the bottom of the bin, and the increase of the unit ventilation rate makes the grain pile get better cooling effect.

Abstract:[Objective] This study aimed to investigate the effects of Yam Polysaccharide (YP) on ulcerative colitis (UC) mice. [Methods] The study included a blank group, YP group, DSS group, and DSS+YP group. The UC model was established by administering DSS water solution, and the treatment group received oral administration of YP for 7 days. Measurement of body weight, DAI score, inflammatory factors in the colon, NLRP3 inflammasome, and HE staining were conducted to evaluate the effects. RAW 264.7 macrophages were treated with 1 μg/mL lipopolysaccharide (LPS) for 24 h to establish the cell inflammation model in vitro. A certain concentration of YP solution was added to the culture medium and incubated with LPS for 24 h. The contents of IL-1β, IL-6 and TNF-α in the cell culture supernatance were detected by enzyme-linked immunosorbent assay. The expression level of NLRP3 inflammator-related protein was analyzed by Western blotting. [Results] Compared to the blank group, the DSS group showed weight loss, extensive ulceration in staining, increased DAI score, and elevated levels of inflammatory factors. Compared to the DSS group, the DSS+YP group showed significant improvement in intestinal damage, and the expression of IL-1β, IL-6, TNF-α, and activation of NLRP3 inflammasome signaling were significantly inhibited in intestinal tissues. In the cell inflammation model, YP pretreatment significantly suppressed the secretion of IL-1β, IL-6, TNF-α induced by LPS, as well as the expression of NLRP3 protein. [Conclusion] YP can improve DSS-induced UC in mice by inhibiting the activation of NLRP3 inflammasome.

Abstract:[Objective] This study aimed to investigate the chemical constituents of walnut leaves. [Methods] The volatile components of walnut leaves were analyzed by head-space solid micro-extraction and coupled with GC-MS. The chemical composition of ethanol extract was identified using ultra-high performance liquid chromatography coupled with quadrupole Orbitrap high resolution mass spectrometry (UPLC-Q-Exactive). [Results] 88 kinds of volatile compounds were identified in walnut leaves, mainly terpenoids, of which sesquiterpenoids account for 78.35%. 30 kinds of active components were identified from ethanol extracts, including twenty kinds of polyphenols (twelve kinds of flavonoids), four kinds of phenylpropanoids, three kinds of pentacyclic triterpenoids, two kinds of essential amino acids and 1 tricarboxylic acid compounds in the ethanol extract in walnut leaves. [Conclusion] The combined use of SPME-GC-MS and UPLC-Q Exactive technology can determine and analyze the chemical composition of walnut leaves systematically, accurately and rapidly.

Abstract:[Objective] This study aimed to investigate the correlation between taste substances and flavor presentation intensity of Shuixian Wuyi rock tea from different storage years. [Methods] The main taste substances, including tea polyphenols, flavonoids, free amino acids, soluble sugars, catechins and other components, were detected in several years of Narcissus (2022, 2018, 2016, 2014, 2012, 2010, 2008, 2006 for storage 1, 3, 5, 7, 9, 11, 13, 15 years, respectively) by using chemical methods and high-performance liquid chromatography, and the reasons for the change of the two and their correlation were analyzed by combining with the sensory evaluation of the electronic tongue. [Results] With the increase of storage year, the contents of tea polyphenols, soluble sugars, and catechins in Narcissus showed a decreasing trend, the total flavonoids and free amino acids showed an inconspicuous trend, and the contents of caffeine, gallic acid, and theaflavin increased in general. Its freshness showed an increasing trend, richness, bitterness, astringency, and its aftertaste showed a decreasing trend, while the salty and sweet tastes fluctuated up and down within a certain level. [Conclusion] EGCG of Shuixian in different years showed a strong positive correlation with a bitter taste, astringent aftertaste, and richness, while EGC showed a strong negative correlation with sourness, TF, and astringency.

Abstract:[Objective] This study aimed to analyze the differences in volatile compounds between the mature green and mature yellow fruits of guava. [Methods] The volatile compounds in 4 kinds of guava fruits during the mature green and mature yellow were detected by gas chromatography ion mobility spectroscopy (GC-IMS). [Results] 130 volatile compounds were detected in 4 kinds of guava fruits ("Yanzhihong", "Sijihong", "Baizhenzhu" and "Siji"). Qualitative analysis showed that the fruit flavored ethyl trans-2-butenate, the grass flavored 2-hexenal and hexanal were the volatile compounds with the highest content among the 4 kinds of guava fruits. The content of volatile components in the mature green and mature yellow fruits of "Baizhenzhu" showed the largest changes, while the content of volatile components in the mature green and mature yellow fruits of "Siji" showed the smallest changes. Compared with the mature green fruits, (E)-2-hexenyl acetate and acetic acid ethyl ester (dimer) showed a significant increase in content in the mature yellow fruits of "Siji", while only alpha-Pinene (monomer) showed a significant decrease. [Conclusion] There are significant differences in volatile components during the mature green fruits of 4 kinds of guava. The volatile components of "Yanzhihong" and "Sijihong" during mature yellow fruits were very similar, but they had significant differences from "Baizhenzhu" and "Siji".

Abstract:[Objective] This study aimed to investigate the effects of two pre-freezing methods (vacuum freezing and atmospheric pressure freezing) and two dipping methods (sucrose impregnation before pre-freezing and sucrose impregnation during freeze-drying) on the quality of freeze-dried apple slices. [Methods] The freeze-drying process was divided into six groups: vacuum pre-freezing without sucrose immersion (VFFD), atmospheric pre-freezing without sucrose immersion (CFFD), vacuum pre-freezing with sucrose immersion (BSVFFD), vacuum pre-freezing with sucrose immersion (MSVFFD), atmospheric pre-freezing with sucrose immersion (BSCFFD) and atmospheric pre-freezing with sucrose immersion (MSCFFD). The main quality indexes of freeze-dried apple slices in each group were analyzed. [Results] The color ΔL^* of the MSVFFD group samples is relatively lower, while Δa^* and ΔE are relatively higher, presenting a deep red color. Sucrose impregnation significantly increased the yield of freeze-dried samples, with the highest in the MSVFFD and MSCFFD groups, followed by the BSVFFD and BSCFFD groups, and the lowest in the two control groups of VFFD and CFFD (P<0.05). Sucrose impregnation significantly reduced the deformation rate of freeze-dried samples, and there was no significant difference among the deformation rates of the four groups with sucrose impregnation, but they were significantly lower than the two control groups of VFFD and CFFD (P<0.05). Sucrose impregnation significantly enhanced the puncture hardness and work of freeze-dried samples. The MSVFFD group had the highest hardness, while the two control groups of VFFD and CFFD had the lowest hardness. Besides, the hardness of the three groups with vacuum freezing treatment was higher than that of the three groups with atmospheric freezing treatment, and the hardness of MSVFFD and MSCFFD groups was significantly higher than that of BSVFFD and BSCFFD groups, respectively (P<0.05). The dried samples of MSVFFD and MSCFFD groups had the lowest moisture absorption rate, while CFFD group had a significantly higher moisture absorption rate than the other groups (P<0.05). [Conclusion] The methods of vacuum freezing and sucrose impregnation during freeze-drying are more helpful in improving the quality of freeze-dried apple slices, and the MSVFFD group endows freeze-dried products with better overall quality.

Abstract:[Objective] This study aimed to improve the water solubility of propolis, and expand the application of propolis in food industry. [Methods] By utilizing the film dispersion method, propolis liposome was prepared with cholesterol and soy lecithin as the wall material and propolis as the core component. The optimal preparation process for propolis liposome was optimized through a combination of one-factor experiments and response surface methodology with the encapsulation rate as the test index, and its antioxidant activity was also analyzed and evaluated. [Results] The optimal process for preparing propolis liposome consisted of 2.5 g/100 mL soy lecithin, a cholesterol to soy lecithin ratio of 1∶10.3, and a cholesterol to propolis ratio of 1∶3.8. These optimized conditions resulted in a high encapsulation rate of 93.09% for propolis liposome. In addition, it was found that the scavenging efficiencies of the 50 μL/mL propolis liposome were 88.60%, 60.53%, and 82.25% for clearance of DPPH radicals, ABTS⁺ radicals, and hydroxyl radicals, respectively. [Conclusion] The prepared propolis liposome has high encapsulation efficiency, good water solubility and good antioxidant capacity.

Abstract:[Objective] This study aimed to develop a method for extracting volatile oil from green-orange peel by reduced-pressure steam distillation. [Methods] A volatile oil tester was combined with a vacuum device for the extraction of volatile oil from green-orange peel, and a regulating valve in the device controlled the vacuum level. The composition and content of volatile oil under reduced pressure and atmospheric pressure were determined by gas chromatography-mass spectrometry (GC-MS), and the in vitro antioxidant activity was evaluated. [Results] The optimum process for the extraction of volatile oil by reduced-pressure steam distillation was: particle size of 8 mesh, solid-liquid ratio of 1∶7 (g/mL), vacuum of 0.082 MPa, time of 40 min, yield of 1.769 mL/100 g. 163 kinds of components were identified in the volatile oil of green orange peel extracted by reduced-pressure steam distillation, which was 33 kinds more than that by atmospheric pressure steam distillation, and the content of major components was increased. The scavenging ability of the volatile oil extracted under vacuum to superoxide anion free radical and hydroxyl free radical was significantly higher than that extracted by atmospheric steam distillation. [Conclusion] The reduced-pressure steam distillation volatile oil extraction has the characteristics of low temperature, short time, high yield, simple operation, and high operability. The obtained volatile oil has a good antioxidant effect, and the method is suitable for the extraction and separation of heat-sensitive substances.

Abstract:[Objective] The construction of limonin-albumin nanoparticles provides a theoretical basis for the further application of limonin. [Methods] Limonin-albumin nanoparticles were prepared by desolvation-chemical crosslinking method using bovine serum albumin as nanocarriers. The optimal preparation process was determined by single factor experiment and response surface test with embedding rate as index, and the nanoparticles were characterized. [Results] When the amount of bovine serum albumin was 64 mg, the amount of lemon bitter was 4 mg, the specific volume ratio of alcohol to water was 5∶1, and the amount of crosslinker was 125 μL, the average particle size and polydispersion index of limonin nanoparticles were (152.2±0.5) nm and 0.196±0.026 respectively. The embedding efficiency was (79.21±0.36)%. The limonin-albumin nanoparticles observed under low-pressure transmission electron microscopy showed a spherical shape. Infrared spectroscopy and X-ray diffraction results showed that limonin was successfully encapsulated in albumin in an amorphous or disordered state. The limonin-albumin nanoparticle suspension has good storage stability. [Conclusion] The limonin-albumin nanoparticles prepared by desolvation-chemical crosslinking method had good storage stability.

Abstract:Carboxymethyl pachymaran （CMP） is a carboxymethylated modification product of the water-insoluble polysaccharides from Poria cocos. It has many biological activities such as immune regulation, antibacterial, anti-inflammatory, anti-tumor, anti-oxidation, liver damage protection and intestinal flora regulation. It has a wide application prospect in functional food, active molecular carrier, medicine and other fields. In this paper, the research of CMP at home and abroad in recent years was focused, the biological activity, preparation, identification and application development of CMP were reviewed, and the future development direction of CMP was prospected.

Abstract:Cultivated meat, as an innovative substitute for conventional meat, is widely recognized as an effective solution to challenges such as meat supply shortages, environmental impacts, and animal welfare concerns. Based on the production technology used, cultivated meat can be categorized into three types: plant-based meat, cell-cultured meat, and microbial protein meat. This review explores the production processes and sensory quality enhancement techniques for these three types of cultivated meat, analyzes their respective technological advantages and challenges, and provides a forecast on the future development trends of cultivated meat products.

Abstract:Ganoderma lucidum has anti-tumor, antioxidant, and immune enhancing effects. This review summarized the latest research progress on the main nutritional components and biological activities of G. lucidum and the current comprehensive utilization status of G. lucidum in medical and health fields, analyzed the existing problems, and prospected the future development direction of G. lucidum.

Abstract:The natural vegetable oil known as Korean pine seed oil is well-known for its high content of being various unsaturated fatty acids, including oleic, linoleic and pinopuric acid. It has been proved that Korean pine seed oil has several physiological benefits such as lowering blood lipids, enhanceing immunity, anti-inflammation, anti-oxidation, enhancing insulin sensitivity, and anti-tumor. This review summarized the extraction methods and pharmacological effects of Korean pine seed oil in recent years, and put forward good suggestions for its application in edible oil and industrial production.