Abstract:Objective: Aiming at the problems of unstable 3D printing quality and low printing efficiency of adipose tissue part of artificial meat based on plant raw materials, studied and improve the intelligent 3D printing trajectory motion algorithm matching with food materials, to reduce the accumulation and corners in the printing path. Methods: A trajectory planning method adapted to the characteristics of artificial meat adipose tissue raw materials was proposed. The complex section layer of the sliced model was divided into several simple polygon sub-partition contours using Bayesian algorithm, and an improved nearest neighbor method was used to determine the optimal motion starting point of each contour. At the same time, the genetic algorithm was integrated into the ant colony algorithm was applied to solve the optimal printing path of the partition contour, and finally the interior of the contour was filled with the improved zigzag scanning algorithm. Results: For the artificial meat adipose tissue in this study, through experimental verification, comparing the existing trajectory planning methods of Cura and Prusa, the established model was printed on a single-layer cross-section, and the printing time and motion path length were reduced, and the quality was good. Conclusion: The proposed trajectory planning algorithm for 3D printing of artificial meat adipose tissue has high feasibility and effectiveness.

Abstract:Objective: This study aimed to explore the differences in the aroma of watermelon seeds under different thermal processes. Methods: The analysis technics such as Headspace-Solid Phase Micro Extraction-Gas Chromatography-Olfactory-Mass Spectrometry (HS-SPME-GC-O-MS) and Electronic Nose (E-nose) were applied. Results: Thermal processing changed the flavor of watermelon seeds from light fragrance to strong roasted flavor; A total of 18 categories including 115 volatile compounds were detected with the help of HS-SPME-GC-O-MS, among which pyrazines, alcohols and aldehydes accounted for 34.25%, 21.07% and 10.99% of the total volatile compounds, respectively; In addition, 63 volatile compounds were discovered in watermelon seeds after microwave treatment, and pyrazines accounted for 53.31% among all these volatile compounds. Conclusion: Thermal processing treatment showed significant influence on the aroma of watermelon seeds, and the aroma of watermelon seeds after microwave treatment was more intense than air-frying and baking treatment.

Abstract:Objective: Building a perfect bioreactor scale-up model provides convenience for enterprise production, and a guidance for reactor manufacturers. Methods: Through the test of 1.5, 5, 20, 200 L scale reactor, the correlation and parameters of the volume dissolved oxygen coefficient kLa and mixing time tm were optimized and explored, the simulation amplification model of bioreactor was established, and the Scaleuper amplification system was built by MATLAB. Results: Compared with the test results, the simulation deviation of kLa was within ±15%. By introducing the definition of critical speed into the correlation of tm, the overall simulation deviation of tm was reduced by 17.4% compared with the original formula. Within ±10%, the simulation deviation of kLa was reduced by embedding BP neural network. The minimum simulation deviation of BP model can reach 0.1% for the training data range. Conclusion: The scale-up model of the reactor based on the empirical correlation has better simulation results after the relevant parameters are measured. It is feasible to use neural network to simulate and amplify the reactor, but it still needs more data training support.

Abstract:Objective: Construction of a simple and rapid method for the analysis of ganoderic acid A （GAA）. Methods: The molecular imprinted polymer （MIP） that can specifically recognize ganoderic acid A （GAA） were prepared by cyclic voltammetric deposition using GAA as template molecule and o-phenylenediamine as functional monomer. The structure, morphology and electrochemical behavior of MIP were characterized by infrared spectroscopy, scanning electron microscopy and electrochemical methods. Using [Fe（CN）₆]^3-/4- as the active indicator, the analytical performance of the sensor for GAA was investigated. Porous MIP for GAA can be prepared on the electrode surface by one-step electropolymerization. Results: The results of quantitative analysis showed that the electrochemical signal of [Fe（CN）₆]^3-/4- had a good linear relationship with the logarithm of GAA concentration in the range of 1.0 pmol/L～1.0 μmol/L, and the detection limit was 0.21 pmol/L. The measured values of GAA in ethanol and water-soluble solution of Ganoderma lucidum powder were 1.15 nmol/L and 3.00 pmol/L, respectively. Conclusion: The MIP-based GAA electrochemical sensor can be used for the rapid determination of GAA in extract solution of Ganoderma lucidum powder.

Abstract:Objective: Rapid determination of organochlorine and pyrethroid pesticide residues in tea beverages. Methods: Selecting the non-ionic surfactant PEG-4000 as cloud point extraction, pesticides were extracted with isooctane by ultrasonic back extraction. The upper layer of isoctane solution was analyzed by Gas Chromatography/Mass. The isooctane solution was separated by HP-5 ms UI capillary column and analyzed qualitatively and quantitatively by GC/MS. Results: The eight pesticides showed a good linear relationship between 0.01～2.0 and 0.02～4.0 mg/L, respectively, with the correlation coefficients (R) of over 0.995. The detection limit and quantification limit of this method were 0.003~0.008 mg/L and 0.01~0.02 mg/L, respectively. The average recovery was 78.3%~98.4%, RSD was 2.7%~8.5% (n=6). Conclusion: The method is simple in operation, high in enrichment rate, practical, safe and economical, which is suitable for rapid determination of pesticide residues in tea drinks.

Abstract:Objective： A method based on high-performance liquid chromatography-mass spectrometry was developed for the simultaneous determination of bisphenol A and nonylphenol in food packaging material. Methods: The extraction solvent and extraction method were investigated. Solid-phase extraction （SPE） conditions were optimized. The effects of solid phase extraction column, loading solvent, eluting solvent and elution solvent on the purification effect were systematically analyzed. The samples were ultrasonic extracted with dichloromethaneand cleaned up on a solid-phase extraction （SPE） cartridge equipped with packing material of silicone. The separation was performed on a Venusil MP C₁₈（2）（100 mm×2.1 mm,2.6 μm）by gradient elution with 0.1% ammonia solution and methanol as mobile phase. The analytes were determined with multiple reaction monitoring （MRM） mode under electrospray negative ionization mode and quantified by an internal standard method. Results: The results indicated that good linearities was obtained for bisphenol A and nonylphenol both within the concentration range of 1.0~200.0 μg/L. The average recoveries of each analyte at three spiked levels of 1.0, 10.0, 200.0 μg/kg were in the range of 89.2%~101.2%, with relative standard deviations （RSD） of 3.1%~6.2%. The limits of detection （LODs） and limits of quantification （LOQs） were 0.5 μg/kg and 1.0 μg/kg, respectively. Conclusion: The method was proved to be a simple, accurate and sensitive method and was successfully applied to detect bisphenol A and nonylphenol in food packaging material. It can also provide reference for the determination of bisphenol A and nonylphenol in food.

Abstract:Objective: This study aimed to help with strengthening the monitoring of antiviral drug residues in animal-derived sports nutrition products. Methods: A method for determining the residues of 9 kinds of antiviral drugs in animal-derived sports nutrition was established, by using hydrophilic interaction chromatography tandem mass spectrometry. The samples were extracted by 1% acetic acid-acetonitrile and purified by PRiME HLB column. The mobile phase system of acetonitrile-10 mmol/L ammonium acetate solution (containing 0.1% formic acid) was separated by Sielc Obelisc R column in gradient elution mode to achieve the separation of nine target components. Results: The 9 kinds of antiviral drugs fractions had good linearity in the mass concentration range of 0.1~20.0 ng/mL, and the limit of detection was 0.1~0.5 μg/kg, with the limit of quantification of 0.3~1.5 μg/kg and the spiked recovery of 82.3%~95.7%, and the relative standard deviation was 3.2%~5.9% (n=5). Conclusion: The test method can meet the detection requirements of the residues of 9 kinds of antiviral drugs in the animal-derived sports nutrition.

Abstract:Objective: A solid phase extraction-gas chromatography/mass spectrometry （GC-MS） method was developed for the simultaneous determination of 24 pesticide residues in coffee peel. Methods: The sample was wetted with water, extracted with acetonitrile, the extract solution is concentrated and then purified with ProElut TPC solid phase extraction column, eluted with acetonitrile and toluene=3∶1, after concentration, the sample was determinated by GC-MS and the peak area was measured by internal standard method. Results: The 24 pesticides were separated well within 28 minutes. The residue of pesticide was in the range of 0.016～0.400 mg/kg, the linearity of the method was good, the correlation coefficient r was between 0.997 9～0.999 9, the quantitative limit was between 0.01～0.03 mg/kg, when the concentration of pesticide is 0.03 mg/kg and 0.30 mg/kg, the recovery rate is between 65.2%～108.5% and 81.4%～105.7%, The relative standard deviation of intra day precision is between 3.7%~6.8% and 2.5%~5.9%, and the relative standard deviation of daytime precision is between 4.2%~7.2% and 2.8%~6.4%, compared with acetonitrile∶toluene=3∶1, as eluting solvent and ProElut TPC as purification column, the elution and purification efficiency were the highest, and the recovery was 95%. Conclusion: The performance parameters of the method meet the requirements of national standards, and the determination results are accurate and reliable. It can be applied to the qualitative and quantitative analysis of multi-component pesticide residues in dried coffee peel.

Abstract:The quality safety risks and quality management issues of traditional fermented meat products were analyzed. This paper put forward suggestions on increasing research and development efforts, accelerating the knowledge benefit transformation process, standardizing the standard system, refining supervision standards, standardizing workshop production, optimizing product markets, strengthening the awareness of social participation, and promoting social co-governance, in order to improve the overall quality and safety level of the traditional fermented meat products industry.

Abstract:Objective: Solving the problem of poor information exchange among the governance subjects will help to improve the governance effect. Methods: By sorting out the typical food safety crisis events of catering services in China in 2021, and analyzing the relationship between blockchain technology and food safety collaborative governance of catering services. Results: Governance information fragmentation, information asymmetry and difficulty in information traceability were realistic dilemma of multi-agent collaborative governance. Blockchain technology and multi-agent collaborative governance had the coupling of information decentralization, security, transparency and traceability. Conclusion: Construct the multi-agent collaborative governance framework enabled by blockchain technology, promote the in-depth integration of blockchain technology and food safety collaborative governance in catering services, construct the technology integration innovation mechanism, and improve laws, regulations and industry standards.

Abstract:Current food safety penalty list positioning fuzzy, content reiterated a lot of the current legislation, to avoid the defects of food safety substance problems. The reason is that the administrative law enforcement excessive list penalty for food safety risk, thus adopted a negative avoidance attitude. It is not only conducive to optimize the business environment, but also will cause adverse effects on food safety in a long-term view. In essence, the formulation of the exemption list is still administrative activities rather than legislative activities. The reconstruction of the food safety exemption list system should replace the current legislation in terms of detailed provisions. The exemption list should be used as the direct basis for administrative law enforcement, and a negative list is established to prevent the risk of the exemption list. By implementing the principle of active, inclusive and prudent regulation, we will balance the relationship between optimizing the business environment and maintaining food safety, so as to give full play to the role of the list of penalty exemptions.

Abstract:Objective: In view of the technical problems such as low efficiency and difficult automatic control of the automatic powder production line for factory rice noodle production. Methods: This research proposed a multi-station automatic powder loading system based on fuzzy control, selecting the deviation E₁ between the detected value of the powder height and the preset value, the deviation change rate EC₁ and the deviation between the current position of the powder loading car and the position to be loaded. The absolute value E₂ was used as the input variable, and the motor speed U₁ and the opening degree of the bin door U₂ of the powder loading system were used as the output variables. The working efficiency of the powder loading system was improved by adjusting the motor speed and the opening of the bin door of the powder loading system through fuzzy control rules. The control system was built on the Siemens S7-1200 PLC platform, and the field test was carried out. Results: The test showed that for the 6-station automatic powder loading and conveying production line, the operation efficiency of this control system was improved by 103.2% compared with the existing control system, and the output of each station per unit time was increased by 31.4%. Conclusion: The number of stations that the system can accommodate 4 points have been raised. The experiment can be used for reference in the design of the control system for realizing high efficiency and automation of the factory rice flour production line.

Abstract:Objective: In order to improve the mixing performance and work speed of a single screw extruder increase. Methods: A coaxial gradual acceleration single screw using planetary wheel assemblies and mixing elements was designed. Using ansys/cfx to conduct the three-dimensional flow field analysis of the flow channel, the macro pressure field, speed vector diagram, speed streaming diagram and axial speed changes, were finished, which was compared to the only traditional pillar. Results: As the speed of the pillar continues to increase, the time for the material to stay in the barrel becomes shorter, and the extrusion efficiency of the gradual acceleration screw can be improved by 20% to 25%, so that the energy consumption is greatly reduced, due to the presence of the kneading block, the material is repeatedly squeezed at the kneading block, so that the gradual acceleration of the single screw in the increase in production capacity at the same time the mixing performance can be guaranteed. Conclusion: The coaxial gradual acceleration of the single screw high-speed rotation of the kneading block can make the material mix more fully, and can shorten the residence time of the material in the screw, improve the output.

Abstract:Objective: The fatigue strength of a new type of vertical retort under the cyclic load of heat engine was studied, especially the residual fatigue life of the pot body after the crack appeared and the factors affecting the fatigue crack propagation of the germicidal pot. Methods: The mechanical characteristics of retort under sterilization and three kinds of cyclic loads were analyzed by Workbench, the design fatigue life of the retort under three alternating stresses was studied based on the S-N curve. The effect of the initial crack size, pressure and temperature on the stress strength factor and residual fatigue life of the crack retort were studied based on fracture mechanics. Results: The design fatigue life of this type of vertical retort was calculated to be 5×10⁵ times, which meet the design requirements, and has a certain safety margin. Based on the fracture mechanics analysis, the crack size life curve of the sterilization retort was obtained, and the residual life of the sterilization retort with defects was predicted, which had certain innovation. Conclusion: Attention should be paid to the occurrence and propagation of cracks in the pot during use. The strength analysis and life prediction analysis of crack defects in the sterilization retort can be carried out according to the method proposed in this paper and experiment.

Abstract:Objective: This study aimed to investigate the factors influencing the oil yield of rapeseed during pressing in a double screw oil press. Methods: To simulate the pressing process of rapeseed and to explore the effects of two factors, the speed of the press screw and the porosity, on the oil yield. Results: The oil yield of rapeseed was linearly related to the porosity, and a larger porosity, was associated with a lower oil yield. Moreover, the oil yield was negatively related to the speed of the press screw. Conclusion: The oil yield of rapeseed was highest when the porosity was 0.45 with the speed of pressing screw at 20 r/min.

Abstract:Objective: To solve the problem that the roller is inconvenient to operate and the concept of rolling friction coefficient and sliding friction coefficient is confused. Methods: EDEM software was used to simulate the white milling process. Taking MNAW18 rice mill as a reference and taking Feng Liangyou series brown rice as a sample, a set of method for measuring discrete element simulation parameters of rice mill was established by independently setting up an experimental bench and combining with simulation calibration. Results: Using the self-made collision coefficient experimental device and video motion processing software, the collision recovery coefficients between brown rice and brown rice, roller and screen were 0.34, 0.24 and 0.43 respectively. Based on the relationship between inclined angle and static friction coefficient, the static friction experiment is designed. The static friction coefficients between brown rice and brown rice, roller and screen were 0.467, 0.881 and 0.550 respectively. The rolling friction coefficient was calibrated through the combination of brown rice stacking angle experiment, brown rice inclined plane rolling experiment and discrete element simulation experiment. The rolling friction coefficients between brown rice and brown rice, roller and screen were 0.013, 0.101 and 0.159 respectively. Conclusion: Through the secondary simulation, the error between the simulation results and the measured results is within a reasonable range, which indicates that the parameter calibration data is reliable.

Abstract:Objective: To reduce grain mildew caused by high water content in storage. Methods: The function model of water content and detection frequency is determined by data measurement in multiple sites. A real-time monitoring system of grain moisture value in the dryer was designed based on STM32 microcontroller. Through the design of parallel plate sensor to detect the change value of capacitance of grain with different moisture content, through the hardware circuit to convert the capacitance value into frequency value. Through the single-chip microcomputer calculation can get the real-time moisture content of grain inside the dryer, and then through RS485 communication transmission to the display screen real-time display. Results: This on-line monitoring error of the set is within 0.5%, and the delay time of the real-time moisture value displayed by the upper computer is less than 0.1 s, which fully meets the requirements of engineering application. Conclusion: Through the field installation test, the system is efficient and will not cause a secondary injury to the grain.

Abstract:Objective: The optimal design scheme of box grid magnetic iron-separator in milk powder production process was explored. Methods: In this study, the working principle of the box grid magnetic iron-separator was explored by using the finite element simulation analysis method under real production conditions in a fully simulated milk powder plant. Through the single factor test, the effects of material drop height, the type of metal foreign matter, the field strength, and the net distance of the magnetic bar on the effective interception rate of the box grid magnetic iron-separator were explored, and the design solution was optimized by using matrix analysis. Results: Assuming that the minimum acceptable standard is an effective interception rate greater than 80% for cast iron, 304 stainless steel and 316 stainless steel, the critical design conditions are as follows: ① When the magnetic field strength of the magnetic bar is 1.0 T, the drop height should be less than 100 mm, the number of layers of the magnetic bar should be greater than or equal to 6, and the clearance of the bar magnet is 25 mm. ② When the magnetic field strength of the magnetic bar is 1.4 T, if the falling height of the material is less than 100 mm, the number of layers of the magnetic bar should be greater than or equal to 4, and the clearance of the bar magnet is 25 mm; If the falling height of the material is between 100 and 300 mm, then the number of magnetic rod layers should be greater than 6, and the clearance of the bar magnet is 25 mm. Conclusion: The research results have industrial application value for milk powder and other powdered food materials, such as protein-based raw materials, powdered fats and oils, starch, food additives, etc.

Abstract:Objective: In order to solve the problems of low automation level and low efficiency of the control system in the current automated production line of hickory shell breaking. Methods: On the basis of the existing automatic production line of hickory shell breaking, a control system of hickory shell breaking automatic production line based on PLC control technology is proposed. With PLC as the core, the control of the whole hickory shell breaking automatic production line was completed, including shell breaking machine, air separator, shell breaking separator, color sorter and other equipment. The feasibility of the method was verified by testing the prototype of a walnut with a diameter of 18~22 mm. Results: Compared with that before the control system was put into operation, after the implementation of the control system, the shell breaking rate of hickory was increased and the damage rate of walnut was reduced. For hickory with a diameter of 18~22 mm, the shell breaking rate was 100%, and the damage rate of walnut was 5.02%, meeting the production requirements. Conclusion: The control technology based on PLC meets the requirements of walnut automatic production line.

Abstract:Objective: The study aimed to improve the storage quality of frozen cooked crawfish tail meat. Methods: Crawfish tail meat were immersed in different proportions of complex phosphate, trehalose and sorbitol antifreeze agents. The thawing loss rate, water content and distribution, water retention, salt-soluble protein, total thiol content, texture properties of crawfish tail meat after freeze-thawed were measured, and the microstructure changes were observed to evaluate the effect of each antifreeze agent. The antifreeze agent with better effect was selected as horizontal factor to design orthogonal experiment, so as to optimize the appropriate recipe of antifreeze agents. Results: 1.5% complex phosphate, 8% trehalose or 10% sorbitol had better cryoprotective effect; The compound antifreeze agent group （1% compound phosphate +6% trehalose +6% sorbitol） had the best cryoprotective effect, and the thawing loss rate was 9.97% under this condition, which was significantly lower than that of the single antifreeze agent group （15.95%, 17.44%, 16.78%）.The combined antifreeze agent group could significantly improve the binding ability of shrimp meat with water and inhibit the damage of ice crystals to muscle tissue during the freeze-thaw process. Conclusion: The combination of antifreeze agents （1% compound phosphate +6% trehalose +6% sorbitol） could effectively improve the cryoprotective ability of cooked crayfish tail meat.

Abstract:Objective: To determine the key points of pear quality formation and deterioration of different Pyrus pyrifolia pears during cold storage. Methods: Zaoshengxinshui, Hujingli18, Hujingli67 were used as materials, the fruit of three varieties with the same ripeness were stored in cold storage at （1.0±0.5） ℃ and relative humidity of 85%~90% for 60 days, fruit texture, total soluble solids, titratable acid, sugar and acid contents and 10 sensor values were determined every 10 days. Results: Hujingli18 and Zaoshengxinshui were the typical type of fructose accumulation,Hujingli 67 was the type of sorbitol accumulation, and all three varieties were the type of malic acid accumulation. During cold storage, the fruit of Hujingli67 can maintain higher firmness with peel, firmness of pulp, crispness and chewiness; Higher content of glucose, sorbitol and total sugar; Stable content of titratable acid and malic acid; The storage flavor is less controlled by the cold storage time; Through the cold storage technology, it shows rich in storage. Hujingli18 is superior to Zaoshengxinshui in peel characteristics, compactness and crispness. Hujingli18 has high fructose, malic acid content and fructose/total sugar, which can keep high sweetness and acidity, and has strong flavor in storage. Zaoshengxinshui is easy to be softened, the content of titratable acid shows a sharp decline trend, the comprehensive flavor is regulated by the storage time, and is less resistant to cold storage. The volatile compounds in fruit of Zaoshengxinshui and Hujing pear 67 were obviously changed, especially the volatile compounds such as nitrogen oxides, methane, sulfur compounds and ethanol. Conclusion: The safe cold storage periods of Zaoxinshui, Hujing pear 18 and Hujing pear 67 are 30,40 and 60 days, respectively.

Abstract:Objective: This study aimed to investigate the effect of slaughtering methods on the muscle quality of eels. Methods: Two slaughtering methods （including mechanical slaughter and manual slaughter） were used to analyze the energy metabolism and physicochemical properties of eel meat slices during storage. Results: Duringstorage at 4 ℃ for 48 h, the glycogent and lactic acid content of eelfillets subjected to mechanical slaughter were lower than those of manual slaughtered samples generally. During 7 d-storage, the sensory deterioration of eel meat samples was retarded by mechanical slaughter, and the TVB-N and TBARS content were lower than those of manual slaughtered samples, while the water holding capacity was higher than that of manual slaughtered samples. Conclusion: Mechanical slaughter is beneficial to maintaining the muscle quality of eels compared to manual slaughter.

Abstract:Objective: In order to expand the scope of cherry sales and achieve rapid grading of cherries under industrial conditions. Methods: Firstly, the YOLOX network was used to detect the defective fruit, in order to solve some problems where the defect was not obvious. The detection accuracy of the inconspicuous defect was improved by setting the appropriate fusion factor for the feature pyramid network, and in order to solve the problem of imbalance between various types of real samples, Focal Loss was integrated into the loss function. Then, the intact fruit was graded using the YOLOX network, and the attention mechanism CBAM was introduced to enhance the network feature extraction. Results: Experimental results showed that 97.59% of the mAP detected for cherry surface defects and 95.92% of the mAP of size and color grading. Conclusion: The accuracy of cherry defects and grading has been significantly improved by the improved YOLOX network.

Abstract:Objective: The study aimed to explore a fast and accurate method to detect brown spot and damage decay in grape bunches. Methods: Colour images （RGB） and near-infrared images （NIR） of red globe grapes bunches were captured by a near-infrared industrial camera. The edges of the samples and the edges of the defective parts were first extracted by applying the Sobel algorithm to the NIR images （NIR）, and then the images were binarized by the adaptive thresholding algorithm to achieve the segmentation of the images. Then the sample edges and fruit stalks were removed by the normalized supergreen method and the finding large connected domain algorithm to extract the shape feature parameters such as roundness, rectangularity and external rectangular aspect ratio of the defective part of red globe grapes bunches and fruit edges, respectively. Finally, a classification model based on BP neural network and support vector machine was developed to discriminate the defective parts and fruit edges. The model enables the rejection of kernel edges to obtain image information of brown spots and damage decay. Results: Using the above-mentioned testing method to verify 60 samples, the accuracy of discriminating red globe grape bunches with intact appearance was as high as 90.00%, those with defects reached 93.33%, and the overall discriminating accuracy reached 91.67%. Conclusion: The study established a method to detect brown spot and damage decay images to enable grading and selection of red globe grapes.

Abstract:This paper reviewed the changes of main components such as chlorophyll, volatile oil, numbness substances and amide substances related to the quality deterioration of Zmnthoxylum schinifolium Sieb. et Zucc during storage. The fresh-keeping technologies of Zmnthoxylum schinifolium Sieb. et Zucc, such as high-temperature steam instantaneous treatment, air-conditioned refrigeration and chemical reagent treatment, were analyzed, and it was pointed out that the comprehensive fresh-keeping technology combining various fresh-keeping methods could be studied in the future.

Abstract:Objective: Optimizing the extraction conditions of polysaccharides from Dendrobium officinale under ultra-high pressure, improving the yield of polysaccharides, and studying its basic properties and antioxidant activity in vitro. Methods: Using D. officinale dry powder as raw material, orthogonal experiment was used to optimize the extraction conditions of polysaccharide from D. officinale by ultra-high pressure technology. The relative molecular weight and monosaccharide composition of polysaccharides extracted from D. officinale by traditional hot water extraction method and ultra-high pressure extraction method were determined, and their antioxidant activities in vitro were compared. Results: Under the optimal conditions of 200 MPa, solid-liquid ratio of 1∶25 （g/mL） and treatment time of 5 min, the polysaccharide yield of D. officinale was 33.3%, which was 128% higher than that of the traditional hot water extraction method. The protein content and relative molecular weight of the extraction method were decreased, while the mannose content was increased. The scavenging ability of DPPH and other free radicals was improved. Conclusion: The polysaccharide extracted from Dendrobium officinale under ultra-high pressure has high yield and good antioxidant activity in vitro.

Abstract:Objective: This study aimed to investigate the effect of Cili extracts in the treatment of enteritis and diarrhea. Methods: The RAW 264.7 cells were treated with different concentrations (1.25, 2.50, 5.00, 10.00, 20.00 μg/mL) of Cili extracts, and then the cell viability was determined by MTT method. RAW264.7 cells were treated with different concentrations of Cili extracts, and then lipopolysaccharide (LPS) was used to induce the cell inflammation model. The content of NO in cell culture supernatant was detected by Griess method. The UC mice model was induced by 3% DSS. The changes of signs during the modeling and drug treatment were observed, and the disease activity index (DAI) was evaluated. The colon length, colon wet weight index and spleen weight were measured. HE staining was used to observe the pathological morphology of colon. The protein expression of Keap1 and Nrf2 in colon tissues were detected by western blot and immunohistochemistry. Results: The concentration of Cili extract ≤10 μg/mL had no significant effect on cell viability (P>0.05). Cili extract inhibited the release of NO, and the inhibitory effect was more obvious with the increase of drug concentration (P<0.05 or P<0.01). Compared with the model group, the colon length of Cili extract group was longer, and the colon wet weight index, spleen weight and DAI fraction were decreased (P<0.05 or P<0.01). HE staining showed that Cili extract had a better protective effect on the intestinal mucosa of UC mice. Western blot and immunohistochemistry showed that Cili extract down-regulated the expression level of Keap1 and up-regulated the expression level of Nrf2. Conclusion: Cili extract had good anti-inflammatory activity in vitro and expressed therapeutic effect on UC mice.

Abstract:Objective: In order to reuse the Areca catechu by-product—A. catechu pedicle, and improve the quality of mycelium of edible fungi, the effect of the pedicle aqueous extract on the liquid fermentation of edible fungi was investigated. Methods: Pleurotus ostreatus, Pleurotus citrinopileatus Singer, and Flammulina velutiper were selected as the test strains, and the effects of the addition of A. catechu pedicle aqueous extract on the quality of mycelium and the activity of enzymes related to the growth and metabolism of the three strains were investigated, by using mycelial growth rate, biomass, mycelial active ingredients and antioxidant activity as indicators. Results: The best growth effect was observed on the P. ostreatus, P. citrinopileatus and F. velutiper when 6.4, 4.8 and 4.8 mg/mL A. catechu pedicle aqueous extract was added, respectively. Compared with the control group, when adding 4.8～6.4 mg/mL A. catechu pedicle aqueous extract, the mycelium active ingredient content was significantly increased, and the mycelium triterpene content of P. ostreatus, P. citrinopileatus, and F. velutiper were increased by 95.24%, 70.91% and 75.00%, respectively. Moreover, A. catechu pedicle aqueous extract increased the antioxidant activity of mycelium, and the antioxidant capacity of mycelium was in the following order: P. citrinopileatus＞F. velutiper＞P. ostreatus; A. catechu pedicle aqueous extract increased the activities of amylase, cellulase, xylanase and laccase of the three strains to some extent, but the effect on the trend of enzyme activity was not significant. Conclusion: Adding the proper amount of aqueous extract of A. catechu pedicle can effectively improve the mycelial quality and the antioxidant activity of the three strains.

Abstract:This review summarized the domestic and abroad research progress of Zizania latifolia in recent years, from the aspects of its nutritional components, health effects, bioactive mechanisms and future research priorities. Moreover, the further research, development and comprehensive utilization of Z. latifolia were also prospected.

Abstract:Objective: This study aimed to explore the effects of selenium-enriched fermentation broth of Armillaria luteo-virens and Tremellodon gelatinosum （Scop.） Pers. on the physicochemical properties and nutritional components of yogurt. Methods: The pH value, acidity, water holding capacity, protein, fat and mineral element contents in yogurt were determined by acidity meter, titration method, weighing method and spectrophotometry, respectively. Results: The sensory scores and acidity of yogurt at a dose of 5 mL/100 mL in two edible fungi fermentation broths were equal to the control group. Except for the 30 mL/100 mL A. luteo-virens fermentation broth, the acidity of the yogurt made from the mixed bacteria under the other fermentation broths was in the range of 70~110 °T. Compared with the control group, 5 mL/100 mL fermentation broth of T. gelatinosum （Scop.） Pers. and 25~30 mL/100 mL fermentation broth of A. luteo-virens significantly improved the water holding capacity and protein contents of yogurt, respectively, and 5~15 mL/100 mL of the fermentation broth of T. gelatinosum （Scop.） Pers. increased the potassium and calcium contents of yogurt. Compared with single bacteria yogurt, 30 mL/100 mL fermentation broth of A. luteo-virens significantly increased the potassium and calcium contents of yogurt with increased by 12% and 54% respectively, while the water holding capacity, protein and phosphorus contents in mixed bacteria yogurt were significantly higher than that of single bacteria yogurt at a dose of 15~20 mL/100 mL A. luteo-virens fermentation broth, rose by 10%~22%, 120%~224% and 52%. Under the condition of 30 mL/100 mL T. gelatinosum （Scop.） Pers, fermentation broth of the sensory score, water holding capacity and fat content of mixed bacteria yogurt were significantly higher than those of single bacteria yogurt, with the rate of 6%, 17% and 41%, respectively. 25 mL/100 mL T. gelatinosum （Scop.） Pers. fermentation broth significantly increased the potassium and iron contents by 34% and 416%, respectively. Conclusion: The low dosage of selenium-rich fermentation broth of A. luteo-virens and T. gelatinosum （Scop.） Pers. could improve the sensory score, pH, acidity, water retention, protein, fat and mineral elements （P, K, Ca, Fe） contents of yogurt.

Abstract:Objective: Improvement of the baking quality of the multi-grain pre-blent bread flour. Methods: On the basis of the previous study on the preparation of low glycemic index multi-grain pre-blent bread flour with oat flour, chickpea flour and wheat flour as the main raw materials, this study employed single factor experiment and response surface methodology to optimize the formula of the pre-blent bread flour. Results: The optimal concentration of xanthan gum, gluten, maltose amylase and ascorbic acid were 0.78 g/100 g, 3.42 g/100 g, 200.00 mg/kg and 171.70 mg/kg, respectively. The specific volume and hardness of the prepared bread were （2.21±0.03） mL/g and （15.97±0.69） N, respectively, which were closed to the bread made with pure wheat flour. The sensory evaluation results （including odor, internal structure, taste and overall acceptability） of the bread prepared from the multi-grain pre-blend flour were better than that of bread made from pure wheat flour. Conclusion: The formula of multi-grain pre-blent bread flour optimized by this study can be used in industrialization.

Abstract:Objective: The main objective of this study was to optimize the soaking and gelatinization process of semi-dry rice noodles. Methods: Taking semi-dry rice noodles as the research object, the effects of soaking temperature, soaking time, gelatinization temperature, gelatinization time and water addition amount on the cooking loss rate and texture characteristics were analyzed, and the better soaking process and gelatinization process were obtained. Results: Soaking temperature 40 ℃, soaking time 2 h, gelatinization temperature 90 ℃, gelatinization time 8 min, water addition 70% were the best process conditions. The semi-dry rice noodles prepared under the optimal process has better cooking quality and texture characteristics. Conclusion: The quality of semi-dry rice noodles can be improved by optimizing the soaking process and gelatinization process.

Abstract:Objective: This study aimed to analyze the peptide composition and evaluate the reproducibility of the soybean oligopeptides. Methods: High performance liquid chromatography tandem high resolution mass spectrometry was employed for peptidomic analysis of the soybean oligopeptides prepared at the same condition at different batches. Generality and individuality of the samples were also discussed based on the heat map analysis and principal component analysis （PCA）. Results: About 1 000 peptides were identified from each of the materials and most of them were short peptides. From the set analysis, 101 peptides were found of detectability from all samples, but there were also many peptides that could be only detected from part of the samples. Moreover, differences between the fifth sample and other samples were evidently observed from the principal component analysis. Conclusion: Though prepared at the same conditions, commonalities and differences coexisted across the samples from different batches. In practical production of oligopeptides, efforts should be made to narrow the differences and increase the commonalities, so that the reproducibility of the products can be improved.

Abstract:This review summarized the technical route and development process of matrix reference materials in China, and the current research progress of steroid hormone matrix reference materials were also introduced. The problems existing in the development and production of matrix reference materials in China and the future development are prospectsed.

Abstract:This paper introduces the low-carbon quantitative index and energy consumption evaluation standard of cold storages, then systematically summarizes the novel low-carbon technologies and their application in cold storages from three aspects: refrigeration technology, cold thermal energy storage and air distribution optimization and finally prospects the development of cold storages in the future.

Abstract:This paper summarized the latest research progress and achievements of electronic nose technology in fruits and vegetables postharvest diseases, including single pathogen infection and multiple pathogens infection. The shortcomings of current E-nose were analyzed, and the development direction of E-nose in fruit and vegetable disease was predicted.

Abstract:The evaluation indicators of fruit wine including sensory evaluation, physicochemical indicator, safety indicator, flavor composition and efficacy are summarized, and the impact of each index on fruit wine quality and research progress are also introduced. Moreover, the quality improvement and the relative quality evaluation system of the fruit wine is prospected.