Abstract:In order to improve the content of linear maltooligosaccharides with specific degree of polymerization in the enzymatic hydrolysis products, the effects were investigated including from the membrane separation, activated carbon adsorption separation, sephadex column chromatography and ion exchange resin column chromatography. The results showed that the membrane separation, activated carbon adsorption separation, sephadex column chromatography and Na⁺/Ca²⁺ ion exchange resins were all not conducive to continuous batch operation. In contrast, K+ ion exchange resins had better effects. Compared with the initial enzymatic hydrolysate, the proportion of G3~G6 and G5+G6 in the permeable solution after separation and purification by K+ ion exchange resin increased by 39.53% and 8.13%, and the recovery reached 78.11% and 63.89%, respectively. In addition, the purity and recovery of G3~G6 and G5+G6 in the end product were further improved by using the simulated moving bed with K+ ion exchange resin as fixed phase adsorbent. This study can provide a reference for the continuous separation and purification of straight malt oligosaccharides in industry.

Abstract:Seven genotype soybean seeds with different protein content were using as the raw material for natto fermentation. The study was focus on the difference of the sensory quality and properties of mucilage on the surface of natto after fermented by Bacillus subtilis natto. Then the relationship between the quality of mucilage and the quality traits of soybean seeds was analyzed. The results showed that, the sensory score and stretch length of natto mucilage fermented from five different genotype soybean except green soybean YSG-10 and black soybean YSB-37 were significantly negatively correlated with seeds protein content respectively (r are 0.953, 0.946 respectively, P＜0.05). Green soybean seed YSG-10 has a relatively low protein content, relatively low sensory score and relatively long stretch length; black soybean seed YSB-37 has the highest protein content, the lowest sensory score and the shortest stretch length, and yellow seed coat with low protein content soybean YSY-102 is suitable for fresh natto while the high protein content soybean YSY-23 is suitable for processing into natto powder, which can provide a reference for the selection and breeding of natto soybean.

Abstract:In order to characterize lipid metabolism of yeasts during sufu manufacture, 23 isolates from sufu pehtze and acidic tofu whey were identified. Ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used to analyse the lipid fingerprints of 7 strains of yeast, after the determination of lipase activities. It is suggested that lipid fingerprint mainly includes 2 kinds of sphingosine, 16 kinds of amide, 22 kinds of ester and 3 kinds of fatty acid. Kluyveromyces marxianus SP-1 and Candida (Pichia) norvegensis SP-5 show highest relative amount of 2-Amino-1,3,4-octadecanetrio and N, N-Dimethylsphingosine, which indicates potential for sphingolipids synthesis. Candida ethanolica ATW-1, Pichia kudriavzeviiSP-4 and Pichia kudriavzevii Y with higher cell-bound lipase activities have more abundant esters. PCA analysis further illustrates the lipid composition of these three strains are more similar to each other. The results indicate that the abundant lipids in yeasts may be closely related to cell-binding lipase.

Abstract:Five kinds of konjac gum from A. guripingensis which molecular weight ranges from 137.8 kDa to 621.5 kDa were obtained by hygrothermal degradation, and the differences of the key performance indicators during the sol-gel transition between them and the κ-carrageenan were compared. The results showed that the gel/sol transition temperature of the compound gel was significantly improved by the partial degraded konjac gum (415.6 kDa), compared with the original one (621.5 kDa), and the transition temperature was increase by 5.98 ℃. Meanwhile, the breaking force, the elongation at break and the water holding capacity of the compound gel were significantly improved (P＜0.05) as well as the storage modulus, the shear stress and the apparent viscosity of the compound was moderately elevated by using the partial degraded konjac gum. Moreover, a dense and ordered structure of the gel was observed by the SEM. A greater hardness and elasticity were showed in the compound gel prepared with the partial degraded konjac gum (233.3 kDa). Our experiments confirmed that the limited degradation of konjac gum from A. guripingensis by using the hygrothermal method, and this is effective way to improve the properties of konjac/κ-carrageenan compound gel.

Abstract:Through intensive sampling of beef during the heating process, the changes of meat quality and all parameters of relaxation signal peaks were studied. The results showed that with the increase of heating time, the semi combined water decreased while the free water increased. In terms of peak shape characteristics, T₂₁ peak width data fluctuated more, T₂₂ peak width increased and height decreased, and the positions of the three peaks shifted left significantly, which reflected that the ordered spatial structure of protein was destroyed and a large number of disordered curls were formed after heat denaturation. The average distance of hydrogen bond between water molecules and peptide chain was shortened and the types were increased. There were extremely significant correlations between peak height, peak width and peak position and meat quality indicators. The mathematical model was established through the nuclear magnetic signal parameters to simulate the changes of physical and chemical indicators of meat products, and the correlation coefficients of water content, cooking loss and b* value reached 0.943, 0.936 and 0.876, respectively. The results confirmed that the information value of shape parameters of LF-NMR was not less than the peak area for food analysis.

Abstract:Thermodynamic moisture retention properties of microbial polysaccharides and seaweed polysaccharides were investigated as compared with water and propylene glycol. Then three common dynamic models of tobacco were selected to fit the hygroscopic and desorption processes of tobacco. The results showed that the moisture retention of Laminaria japonica polysaccharides and Spirulina platensis polysaccharides was significantly better than that of propylene glycol, and page model was the best. Considering the thermodynamic and kinetic factors according to the moisturizing index, Laminaria japonica, Spirulina platensis and Hericium erinaceus polysaccharides were considered to have better moisturizing effect. Low field nuclear magnetic results showed that the addition of aforementioned three polysaccharides increased the chemically bound water content in tobacco as compared with the addition of water and propylene glycol, thus the moisture in the tobacco is less likely to be lost.

Abstract:Soluble soy polysaccharides (SSPS) with different structure characteristics were obtained by controlling the conditions of acid hydrolysis, alkaline de-esterification and proteolysis. The effect of processing on the structure characteristics of SSPS and its foaming properties were discussed in details. The structure properties of SSPS were characterized by monosaccharide composition, average molecular weight, degree of esterification (DE), and protein content. The foaming properties of SSPS were expressed by the foam expansion rate (FE) and the foam stability (FS). The results showed that the acidic hydrolysis process could degrade the SSPS main chain structure and gradually reduce the molecular weight pf SSPS, but could not affect the DE and protein content. With decreasing of molecular weight, the foam expansion rate (FE) of SSPS increased, while the foam stability (FS) decreased. The alkaline de-esterification process did not affect the molecular weight, but reduced the DE and protein content simultaneously. The FE and FS of the product also decreased simultaneously with the decreasing of the DE and protein content. SSPS with different protein content was obtained by proteolysis. Proteolysis did not affect the molecular weight and DE of the product. The results of FE and FS showed the FE and FS of SSPS decreased simultaneously with the decreasing of protein content. All these data suggested that the protein content and average molecular weight of SSPS played a more critical role in its foaming properties compared with the DE. The findings should be of value for the preparation of SPI with good foaming performance.

Abstract:In order to investigate the difference of the puff-by-puff release of nine major components (tar, nicotine, CO, NNK, B[a]P, phenol, crotonaldehyde, HCN and NH3) in mainstream smoke of slim and normal cigarettes, typical flue-cured cigarette samples from same cut tobacco were smoked by smoking machine under ISO. Results showed that: ① The average puffs of slim and normal cigarettes were 5.49 and 6.72 respectively, which showed there were significant statistical differences. In general, the puff-by-puff and total release of all components from slim cigarette were lower than from normal cigarette. and puff-by-puff release deviations of tar, nicotine, NNK, B[a]P, phenol, HCN and NH₃ in slim cigarette were smaller than normal cigarettes, while the law of CO and crotonaldehyde were opposite; ② With the proceeding of puffing, the puff-by-puff release of tar, nicotine, CO, NNK, B[a]P, phenol, HCN and NH₃ release per puff increased in both slim and normal cigarettes, except the crotonaldehyde release of the first puff; ③ The correlation trend between puff-by-puff yield of nine main components and puff number in normal cigarette were more significant than slim cigarette, while the factor of tar was controlled, the degree of change in correlation was opposite.

Abstract:To determine the nutrients contents in Miichthys miiuy muscle and by-products. The contents of moisture in Miichthys miiuy muscle and by-products were 79.65%, 69.15%; crude protein were 18.65%, 19.36%; crude fat were 0.24%, 3.90%; and crude ash were 1.15%, 3.75%, respectively. Total amino acids (TAA) contents of Miichthys miiuy muscle and by-products were 18.58%, 15.47%, and essential amino acids (EAA) contents were 7.65%, 5.52%, respectively. However, only EAA/TAA (41.17%) and EAA/non essential amino acids (NEAA, 69.99%) of Miichthys miiuy muscle met FAO)/WHO standard for protein profile. According to amino acid score (AAS) and chemical score (CS), methionine was the first limited amino acid in Miichthys miiuy muscle and by-products. The essential amino acids index (EAAI) of Miichthys miiuy muscle and by-products was 89.07, 61.78, respectively. The contents of butyric acid, palmitoleic acid, oleic acid, nervonic acid, docosahexaenoic acid (DHA), magnesium (Mg), calcium (Ca), potassium (K) and iron (Fe) were high in Miichthys miiuy muscle and by-products. Miichthys miiuy muscle and by-products are kinds of nutrition rich food source with high content of protein, low content of fat and high contents of mineral.

Abstract:In order to understand the comprehensive nutritional value of Guangxi chestnut growing in Counties Tiane, Longlin and Longan, the nutritional components, antioxidant components and processing characteristics of raw and cooked chestnut were compared and analyzed. The results showed that the quality of chestnut varies with the place of production and the state of ripeness. The cooked chestnut had a darker color, higher fat, amino acid content and water holding capacity, while the raw chestnut had higher soluble protein and vitamin C (V_C) content, and stronger ability of scavenging free-radical and oil-holding capacity. However, the raw chestnut exhibited the higher content of the soluble protein and V_C, stronger oil-absorbing capacity and DPPH free-radical scavenging ability. Comparing with other regions, the raw chestnut from Tiane had brighter and yellower color. It exhibited the higher content of the soluble sugar, fat, amino acids, essential amino acids and V_C. The cooked chestnut from Tiane exhibited the higher content of amino acids and essential amino acids. The results of cluster analysis showed that the raw and cooked chestnut from Tiane were clustered into one group. All the above results suggested the quality of chestnut from Tiane was better. The raw chestnuts from the three places may be more suitable for foods such as cookies, peach crisps, puffing, etc., while cooked chestnuts are more suitable for products such as chestnut paste and bread.

Abstract:The surface-enhanced Raman spectroscopy (SERS) technology and the two-dimensional correlation spectroscopy (2D-COS) were used to optimize the characteristic variables of the Enrofloxacin in chicken meat. The partial least squares regression method (PLSR) was used to establish Enro the characteristic peak analysis model of sand star was compared with the competitive positive adaptive weighting algorithm (CARS). The results showed that the 2D-COS-PLSR model has the best effect, and its Rc and Rp were 0.979 7, 0.997 2 respectively, which shows that it is feasible to use 2D-COS to optimize the characteristic spectral peaks related to the concentration of enrofloxacin in chicken.

Abstract:In order to establish a double antibody sandwich ELISA method for the rapid, sensitive and specific detection of peanut allergenic protein Ara h 1. Taking Ara h 1 murine monoclonal antibody (mAb) as capture antibody, and Ara h 1 rabbit polyclonal antibody (pAb) as detection antibody, the checkerboard method was used to optimize the antibody working concentration to establish the method, and the detection characteristics were identified, including sensitivity, specificity, accuracy and stability of the method. Results: The optimal working concentrations of mAb and pAb were 1∶10 000 and 1∶8 000 dilution, respectively. The linear range of the ELISA standard curve was 4~256 ng/mL, and the limit of detection was 4.16 ng/mL. The average recovery ranged from 85.9% to 94.5%, and there was no cross reaction with other common allergenic proteins. In addition, the detection results stable within 90 days under the condition of 4 ℃ in the dark and sealed. The established double antibody sandwich ELISA method is sensitive, specific, accurate and stable, which can be used for the rapid screening of peanut allergenic protein Ara h 1.

Abstract:A method of high pressure ion chromatography (HPIC) for quickly determinating bromate and nitrite in drinking water was established. The contents of bromate and nitrite in the sample were determined by using Dionex Integrion high-pressure ion chromatograph, IonPac AS19 high-capacity analytical column and inhibition conductivity detector, with the eluent of KOH produced on-line by automatic generation device. The anions of bromate and nitrite could be separated by the method within 5 min with detection limits of 0.46 μg/L and 0.22 μg/L respectively. In the concentration range of 0~100 μg/L for bromate and 0~50 μg/L for nitrite, a good linear relationship was found. By adding standards to the water, the recovery of bromate and nitrite was 98.6%~101.3% and 100.1%~106.0%, respectively, and the relative standard deviation was 1.26%~4.12% and 1.69%~4.27%. This method was simple, rapid, sensitive, accurate, efficient and environmentally friendly which was suitable to determinate the trace of bromate and nitrite in drinking water.

Abstract:A method for the simultaneous determination of 10 fungicides residues in vegetables by gas chromatography- mass spectrometer (GC-MS/MS) was established. The samples were extracted by ethyl acetate cyclohexane, and the aminosolid phase extraction column purification was preferred. Which were detected by multi-reaction monitoring (MRM), and quantified by external standard method. The results showed that the linear relationship of 10 fungicides in the mass concentration range of 15~500 ng/mL was good, and the correlation coefficient was all greater than 0.999 1, with the detection limit of 0.1~0.5 μg/kg. The actual recoveries of the samples were 84.7%~117.0%, and the relative standard deviation (n=6) was 0.4%~4.7%. This method is suitable for the simultaneous detection of a variety of fungicides in vegetables.

Abstract:Firstly, orthogonal test design was adopted to optimize the best working conditions (acetylene flow, hollow cathode lamp flow, burner height) of atomic absorption spectrometry for the eight kinds of essential elements, including potassium, calcium, sodium, magnesium, iron, copper, manganese, and zinc. Single-factor experimental design was adopted to optimize the best working conditions (ashing temperature, ashing time, atomization temperature, atomization time) of graphite furnace atomic absorption spectrometry for the two toxic elements of lead and cadmium. Thereafter, the standard curve of atomic absorption spectrometry for each element under the best working conditions of the instrument was established, and the detection limit and precision of the method were investigated. The sample pre-treatment conditions were optimized. Under the control of the optimal sample pre-treatment conditions, the sample spiked recovery rate was determined, and flame atomic absorption spectrometry of eight essential elements and graphite furnace atomic absorption spectrometry of two toxic elements that meet the requirements of detection were established. Finally, the corresponding ten elements in eight Jiangxi famous teas were determined by these established methods and further compared. The results showed that these established atomic absorption spectrophotometry methods all had good linear relationship in the corresponding concentration range. The correlation coefficients were 0.991 8~0.999 2, and the precision RSD values ranged from 0.77% to 3.32%, with the detection limits of 0.004~0.050 g/mL and the recovery rates of 99.25%~102.25%. The results showed that some significant differences in the contents of the ten kinds of elements in the eight types of tea were found, with a certain order, i. e. K ＞ Mg ＞ Mn ＞ Ca ＞ Fe ＞ Na ＞ Zn ＞ Cu ＞ Pb ＞ Cd. Suichuan Gougunao tea contains the highest contents of K, Ca, and Fe and Lushan Yunwu tea has the highest Na content. The highest Mg and Zn contents are Jing'an white tea. The highest Mn content is Jinggangshan green tea. Wuyi black tea was found to contain the highest Cu content, while Pb and Cd contents are lower in eight types of tea. These atomic absorption spectrometry methods established in this study are easy to operate, and have less interference and high sensitivity, which also can be used for the determination of the corresponding element content in various other tea. The contents of four kinds of the constant elements of potassium, calcium, sodium, magnesium and four kinds of trace elements of iron, copper, manganese, and zinc, are rich in eight types of famous Jiangxi teas. However, the contents of two kinds of toxic elements, Pb and Cd, are lower than national standards.

Abstract:Using the integrated design concept and a combination of theoretical analysis and simulation, a high-efficiency and flexible pipe chain conveyor with cleaning devices is designed. SolidWorks 3D modeling software is used to model each part of the equipment in blocks, and virtual assembly is carried out to ensure that the design structure is designed reasonably, and that the pipe chain conveyor equipment can complete the functions of conveying materials and cleaning up residue. The simulation results show that the designed pipe chain conveying equipment completes the conveying of materials while the real simulation software simulates and analyzes the key components of the conveying equipment, which verifies the rationality of the design.

Abstract:Based on the movement principle of the crawling worm in nature and the characteristics of its structure and movement, a soft pipe crawling robot is designed with the hexaprism driver and the cylindrical driver as the main body of the robot. Two kinds of motion modes of the robot in the pipeline are analyzed.By using the finite element analysis technology, the deformation of the hexagonal prism driver and the cylindrical driver are verified to meet the robot motion requirements. Finally, the motion parameters of the robot in different motion modes are obtained through experimental tests, and the motion performance of the robot is determined. The results show that the structure and motion mode of the robot are feasible.

Abstract:In this paper, motion formulae of two degree freedom seven-bar mechanism are derived a mathematical model is established for optimal design of the seven-bar leg mechanism of mobile robot. The elliptic trajectory curve with the long half axis of 100 mm and the short half axis of 40 mm is selected as the relative ideal trajectory curve of robot foot endpoint. The two degree freedom seven-bar robot leg mechanism is optimized by using the genetic algorithm. The foot endpoint actual trajectory curve of the optimized seven-bar leg mechanism of robot almost coincides with the ideal elliptic trajectory curve. The maximum and minimum x coordinates of the foot endpoint are respectively 100.035 mm and 100.036 mm, and the maximum and minimum y coordinates are respectively 40.005 mm and 40.009 mm. The maximum relative error with the long axis and short axis radius of the ideal ellipse trajectory is only 0.036%. Applying the optimized two degree freedom seven-bar robot leg mechanism, the hexapod simulation robot is designed. The motion simulation of the optimized seven-bar robot leg mechanism and the hexapod simulation robot are carried out by UG software, and the simulation result are satisfactory.

Abstract:A 9-point distributed thermocouple was used to measure the temperature field distribution of each layer of the oven in real time, and the oven temperature uniformity was determined and analyzed. Moreover, the internal temperature field of the oven was numerically simulated using computational fluid mechanics knowledge. The results showed that the uniformity of the temperature field inside the oven was significantly improved, by optimizing the structure of the rear baffle in the oven, adjusting the distribution of air volume, and changing the layout of the air outlet.

Abstract:The box type hot air dryer with controlled temperature and humidity was designed. The drying machine mainly consists of internal recycle fan, heating system, humidifying equipment, weighing unit, and automatic control system. The experiment result showed that under 60 ℃ and 20% relative humidity, internal temperature and relative humidity were uniform and drying time was consistent in different positions with no significant differences. The material temperature changing curves seemed to be consistent under the same enthalpy value drying condition. Additonally, step-down relative humdity dyring method improve drying efficient a lot.

Abstract:Aiming at the problems of low control precision and slow response speed of the existing food drying equipment thermostatic control system, this paper presents and designs a kind of food drying equipment thermostatic control system based on platinum resistance as temperature sensing device and hardware closed-loop control circuit for constant temperature control. The test results show that the constant temperature error of the system is within ±0.1 ℃, and the average response time of constant temperature is 4 min 56 s, which can effectively improve the system constant temperature control accuracy and response speed.

Abstract:In order to improve the weighing accuracy and realize the automation of batching process, a set of automatic weighing and batching equipment based on PLC is designed. The equipment includes three sets of silo assembly, which can store and supply different solid materials according to the formula. The function of control system includes formula management, parameter debugging, automatic weighing, alarm display and so on. The material feeding process is not only divided into coarse feeding and accurate feeding, but also introduces compensation coefficient,which effectively improves the weighing accuracy. By analyzing the test results, the equipment improves the weighing accuracy, it can reaches 96.7% that the probability of each material weighing error within the range of ±3 g.

Abstract:In order to improve the automatic filling level of multi particle oil capsicum materials, a new generation of oil capsicum filling machine control system is developed by using PLC control technology in combination with the physical characteristics of oil capsicum materials and the filling process requirements of the enterprise. The control system is debugged and filled with 210, 220 and 280 g bottles of Laoganda oil capsicum series products. The results showed that the qualified rate of the control system was 100%, the filling speed was about 411 bottles/hour, and the average solid content of each bottle was about 63.6%. It can realize the high-speed and accurate automatic filling of multi particle oil and pepper materials, meet the production demand of the enterprise.

Abstract:For the problem that the actual flow detection value of the screw feeder differs greatly from the calculation value of the traditional calculation formula, an RSM eperimental design is used to modify the flow calculation formula of the screw feeder. Considering the complexity of the actual test, the ratio of the flow value measured by the discrete element simulation and the value calculated by the calculation formula is used as the response, and the RSM experimental design is designed by taking the screw pitch, speed, and pipe diameter that significantly affect the flow difference as the factors. The second-order regression equation between the factors and the response value, from which the flow calculation formula of the screw feeder is further obtained. In order to verify the feasibility of the flow calculation formula, the SolidWorks software was used to establish a three-dimensional model according to the design requirements, and the EDEM software was imported for discrete element simulation. The flow value obtained from the simulation was found to be 1.258 t/h. The error of the calculated flow value of 1.210 t/h with the correction formula is 3.97%, indicating the rationality of the flow correction calculation formula and providing a reference for the design calculation of the screw feeder.

Abstract:The multi-sensory packaging design is made through establishing channels outside of the visual senses, which can enhance the sensory stimulation for consumers, and promote the emotional communication between products and people. It is more fun and interactive, in line with the humanization design concept. The multi-sensory packaging design is different from general packaging design, which make the customers not only from the visual sense experience, but pay more attention to the value of the tactile experience, deepen the sensory experience emotional impact, and improve the product identification from the multi-sensory experience. It is pointed out that multi-sensory packaging design should follow the principles of integrity, practicability and innovation.

Abstract:Aiming at the obvious reality of the homogenization phenomenon, the significance of the defamiliarization expression in the local food packaging design was expounded. The multi-dimensional expression was carried out, including the defamiliarization of the local food packaging design in terms of concept presentation, visual stimulation, function expansion, and situation creation. The direction of the future local food innovation design was also prospected.

Abstract:With air filled in the box as a control group, three groups of different atmosphere-packaging atmosphere ratio, pre-treated four mixed fresh cut fruits and vegetables of carambola, Dangshan pear, cucumber, wheatgrass, stored at 4 ℃, Determine and analyze the quality of mixed fresh-cut fruits and vegetables by measuring and analyzing its physical and chemical indicators. The results showed that the mixed fresh-cut fruits and vegetables treated with 5% O₂+5% CO₂+90% N₂ had higher sensory quality after 8 days of storage, lower weight loss rate, good color and hardness, and lower soluble solids content. Growth is inhibited. It shows that the modified atmosphere packaging has good fresh-keeping effect on 4 kinds of fresh-cut fruits and vegetables mixed with carambola, Dangshan pear, cucumber and wheatgrass, among which the freshness-preserving effect is the best under the atmosphere ratio of 5% O₂+5% CO₂+90% N₂ With air filled in the box as a control group, the fresh-cut fruits and vegetables including carambola, Dangshan pear, cucumber and wheat grass were packaged and stored at 4 ℃. The quality of fresh-cut fruits and vegetables was determined by measuring and analyzing their physicochemical indexes. The results showed that the mixed fresh-cut fruits and vegetables treated with 5% O₂+5% CO₂+90% N₂ had higher sensory quality, lower weight loss rate, good color and hardness, and slow decrease of soluble solid content, with the inhibition of microbial growth after 8 days of storage. The results showed that the fresh fruit and vegetables mixed with carambola, Dangshan pear, cucumber and wheat grass were kept fresh by gas conditioning packaging, among which 5% O₂+5% CO₂+90% N₂ was the best.

Abstract:Aiming at the problems of complexity and minuteness of egg crack detection, the improved particle swarm optimization algorithm is proposed in order to improve the detection effect. Firstly, the inertia weight was adjusted with cosine function, having the large value in the early stage and small value in the later stage. Secondly, particle reverse learning was prevented from falling into the extreme value trap, and the optimization was improved efficiently. Thirdly, adaptive threshold was segmented the egg image, variable median filter window was removed the dark spots on the egg image surface, and incomplete Beta function was enhanced the image. Finally, the process was given. The experimental simulation shows that improved particle swarm optimization algorithm would detect the reticular crack and linear crack, and the edge of the cracks are clear, with correct detection rates of obvious linear and reticular cracks of 96.4% and 94.7%, and correct detection rates of non obvious linear and reticular cracks of 89.2% and 87.5%, respecitiveley which are higher than other algorithms.

Abstract:Plum fruits was used to evaluate the effects of biological preservative paper, soaked with natamycin and ε-polylysine separately, on their storage quality at 20 ℃. To reveal the mechanism, the decay ratio, weight loss rate, respiratory intensity, ethylene production rate, hardness, malondialdehyde, total soluble solids, titratable acid, V_C content, and number of mold and yeast colonies were measured during the plum storage. The results showed that comparing with control, natamycin and ε-polylysine preservative paper could obviously inhibit the increase of fruit decay ratio, weight loss rate, and malondialdehyde content, and reduce the respiratory intensity, ethylene production rate, and the number of mold and yeast colonies. Moreover, the treatments could also maintain the fruit hardness, total soluble solids, and the contents of titratable acids and V_C. In summary, the natamycin treatment was better than that of ε-polylysine, which could maintain good storage quality and delay plum fruit senescence.

Abstract:In order to realize the visible/near infrared spectroscopy nondestructive testing of the internal quality of orange fruits, Trace pro software is used to carry out optical simulation analysis on the designed orange fruit online testing and conveying tray model. referring to the luminance/illuminance value in the simulation result, the tray model with higher value is processed in kind, and is tested and verified by combining with the actual spectrum testing platform.The simulation results show that the optimal shape parameters of the achievement transfer tray were: outer diameter 80 mm, inner transverse diameter 55 mm, inner longitudinal diameter 50 mm, and thickness 20 mm. Different materials were used to process the tray for the detection of soluble solids content (SSC) of actual orange fruits. After the spectral data were preprocessed, the partial least squares regression (PLSR) prediction model was used, among which acrylic tray had the best prediction result. In order to further optimize the detection model, genetic algorithm (GA) and stability competition adaptive re-weighted sampling (SCARS) algorithms are used to extract spectral characteristic bands respectively, and a prediction model of PLSR of orange SSC is established. The SCARS algorithm has the best feature extraction method, and the prediction decision coefficient R is 0.920 9. The predicted rms error (RMSEP) is 0.468 3.

Abstract:In view of the problem that it is difficult to predict the inner pulp defect of banana, the machine vision technology is employed to recognize the image of banana peel and pulp, and then fits the recognition parameters to get the prediction model of pulp defect. The collected image, grayed and filtered, is recognized by double threshold and morphological analysis to extract banana peel, banana pulp, banana peel black spot and banana pulp defect. Thereafter, the total number of pixels in the extracted region is calculated, and the total number of pixels is taken as the area of the region. The ratio of the total area of banana peel / total area of banana pulp to the area of black spot of banana peel / defect area of banana pulp is used to define the degree of black spot of banana peel and defect of banana pulp. Using polynomial fitting method, the prediction function of pulp defect is obtained according to the training samples, and the residual analysis is carried out. The accuracy of banana grading was 88.9%. Compared with the other method to predict the defection of class by peel of banana, the accuracy of prediction mathematic is better, indicating the more practice value of predicting by flesh of banana in this study.

Abstract:The peptide ferrous chelate was prepared using tilapia scale collagen peptide and ferrous chloride salt as raw materials, and its optimal chelating conditions and chelate structure were investigated. Using chelate yield as an indicator, the chelation conditions were optimized by single factor and response surface methods; The structure and amino acid composition of the chelate were analyzed by scanning electron microscope, Fourier infrared spectroscopy, X-ray diffraction and amino acid analysis. The results showed that the optimal reaction conditions for preparing the chelate were pH 5.30, peptide concentration 3.00%, and peptide to iron mass ratio 3.2∶1.0. Under these conditions, the chelation rate was 82% and the chelate yield 65.43%; The analysis of amino acid composition showed that the amino acid composition accorded with the composition characteristics of collagen polypeptide, and the content of aspartic acid, glutamic acid, lysine, histidine and arginine increased after chelation; Diffraction and other results showed that the peptide and ferrous salt were combined by a coordination bond to form a peptide ferrous chelate.

Abstract:The Vigna umbellata lectin as the research object, based on the results of single factor experiments, the extraction process is optimized by response surface experiments. Further purification was made by using ammonium sulfate fractionation precipitation method,Q Sepharose XL anion exchange chromatography, phenyl FF HP hydrophobic chromatography and Sephadex G-50 gel filtration chromatography, and the protein was analyzed by SDS-PAGE electrophoresis. The results showed that the optimum extraction parameters were as follows: PBS is used as the extracting solution, the ratio of material to liquid was 1∶23 (g/mL), pH value was 7.8, and the duration was 14 h and the agglutination activity of lectin was (37.18±0.18) HU. The agglutination activity of the purified lectin reached 127 HU. Identification of purified lectin has two subunits and the molecular weights were around 55 kDa and 27 kDa.

Abstract:In order to determine the nutritional quality and antioxidant activity of melon seed oil, the oil was extracted from the dried Leping melon seeds seed by solvent method, and its basic physical and chemical indexes were measured. The fatty acid composition, triglyceride, tocopherol, and sterol composition of melon seed oil were analyzed by the method of GC(gas chromatography) and LC(liquid chromatography), and its antioxidant activity was evaluated. The results showed that the basic physical and chemical indexes of Leping melon seed oil met the national standard of edible oil; fatty acid analysis revealed that the content of unsaturated fatty acid was 83.16%, of which the content of oleic acid and linoleic acid were 12.8% and 69.9%, respectively, and the content of polyunsaturated fatty acids reaches 70.277%; the triglyceride composition was determined with 16 kinds of triglycerides, of which unsaturated fatty acid triglycerides, namely LLL, OLO, OLL, and PLO, accounted for about 85% of the total triglycerides. The sterol content reached 4 154.49 mg/kg, with the highest content of sitosterol; the tocopherol content was 951 mg/kg, mainly α- and γ-tocopherols, and rich in mineral elements; and the ability of DPPH free radical scavenging was 92.31%, which showed it had good oxidation resistance ability.

Abstract:In this study, the water-extracted ethanol precipitation method was used to extract Polysaccharides in Pyropolyporus Formentarius (PFPS), and the capacities of scavenging DPPH and ABTS were analyzed. Different concentrations of PFPS were used to detect the resistant abilities against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, and Micrococcus tetragenus, and the relative minimum inhibitory concentration (MIC) were also determined. The results showed that PFPS could eliminate DPPH and ABTS. When the concentration of PFPS was 1.0 mg/mL, the ability of scavenging DPPH and ABTS exceeded that of the BHT control, while was weaker than the VC reference substance. The antioxidant activity of PFPS with different concentrations was significantly different. PFPS had inhibitory effects on the four tested bacteria and there were significant differences, and the strongest inhibitory activity was resistant against E. coli. The minimum inhibitory concentrations of E. coli, S. aureus, B. subtilis, and M. tetragenus were 1.25, 1.25, 2.50, 5.00 mg/mL, respectively. In summary, PFPS had good antioxidant and antibacterial activities, with gradually increasing associated with the polysaccharide concentration.

Abstract:To study the physicochemical properties and antioxidant activity of ethanol-graded polysaccharides of Glehnia Radix. Four kinds of polysaccharides of Glehnia Radix (GLP-30, GLP-50, GLP-70, GLP-residual) were fractionated and purified by water extraction and alcohol precipitation. Fourier transform infrared spectroscopy, high performance liquid chromatography, and gel permeation chromatography, scanning electron microscopy, and differential scanning calorimetry-thermogravimetric analysis were used to evaluate the physicochemical properties and structure characteristics of polysaccharides. The antioxidant activities were also studied. The four polysaccharides of Glehnia Radix have the typical groups of polysaccharides, but the results of differential scanning calorimetry are quite different, which may be due to the differences in the sugar chain spatial structure. The molecular weight of each polysaccharide were decreased with increasing ethanol concentration. The yield and monosaccharide content were different among different polysaccharides. The yield (5.43%) and the content of galacturonic acid (2.03%) of GLP-50 were the highest. It also has the highest oil-retaining property, and the highest antioxidant activities in DPPH and hydroxyl free radical scavenging. The ethanol fractionation method can be used to fractionate and purify the polysaccharides of Glehnia Radix. The final concentration 50% ethanol was more suitable for the preparation of Glehnia Radix polysaccharides for its stronger antioxidant activity.

Abstract:In this study, ultrasound-assisted extraction of polyphenols from paeonia ostii oil peony seeds was used. On the basis of a single factor test, the material-liquid ratio, ultrasonic time, extraction temperature and ultrasonic power were set as independent variables, and the polyphenol yield was response value, optimize the extraction process of peony seed polyphenols by Box-Behnken response surface method. The results showed that the best conditions for extracting polyphenols from peony seeds were the ratio of material to liquid 1∶14 (g/mL), ultrasonic power 160 W, ultrasonic time 98 min, extraction temperature 57 ℃. Under the best technological conditions, the extraction rate of polyphenols in peony seeds was 33.38 mg/g. According to in vitro antioxidant experiments, peony seed polyphenols can effectively remove DPPH free radicals and ABTS free radicals, have a certain degree of antioxidant capacity, and can become a new natural antioxidant. This study is a comprehensive development of peony seed provide theoretical basis and reference.

Abstract:The large yellow croaker liver was used as the raw material, and the optimal protease was used to extract and extract the large yellow croaker liver oil. Taking the large yellow croaker liver oil extraction rate as an evaluation index, the best enzymatic extraction process was determined through single-factor experiments and response surface experiments. The extraction rate, quality, and fatty acid composition of the large yellow croaker liver oil were compared with those obtained by light alkali method. The results showed that the best enzymatic extraction conditions were as followed: for large yellow croaker liver was using neutral protease, the ratio of material liquid ratio was 1∶2, the amount of enzyme added was 2.5%, the value of pH was 7.3, the hydrolysis time was 4 h, and the hydrolysis temperature was 50.3 ℃. Under the conditions, the extraction rate of large yellow croaker liver oil was 78.39%, and the quality was better than that of light alkali method. The oil was clear, the acid value was (5.83±0.15) mg/g, the iodine value was (142.65±0.22) mg / 100 g. There were 13 kinds of fatty acids, 5 more than that of light alkali method. There are 8 kinds of unsaturated fatty acids, including 19.71 g/100 g saturated fatty acids, 62.63 g/100 g monounsaturated fatty acids and 17.62 g/100 g polyunsaturated fatty acids. The extraction rate, quality and fatty acid composition of liver oil from large yellow croaker by enzymatic method were better than those by alkali method.

Abstract:In order to study the effect of processing technology on the volatile flavor components of Zhijiang duck, SPME combined with GC-MS spectrometry was used to detect the types and types of volatile flavor substances in the four stages of raw meat, fried, fried, and sterilized. Relative content. The results showed that the number of volatile flavor components after the four processing stages of raw meat, deep-fried, fried, and sterilized were 44, 19, 39, and 39, respectively. Among them, aldehydes, terpenes, alcohols, and ketones are the main flavor substances, followed by esters, alkanes, and other heterocyclic compounds. Principal component analysis showed that the substances that had a greater effect on the flavor of the Zhijiang duck were methylheptenone, linalool, benzaldehyde, 2-heptanol, eucalyptol, n-octaldehyde, nonanal, and bromocyclopentyl Alkane, 1-nonanol and terpenes, etc... The sterilization process had the greatest influence on volatile flavor substances in each process.

Abstract:Nutritional components of highland barley flour were analyzed, including protein, fat, ash, moisture and amino acids. The processing parameters for highland barley chips was studied, including extrusion puffed, pre-drying and roasting. The results showed that, in the highland barley flour, the protein contents of protein, fat, moisture and ash were 10.23 g/100 g, 2.51 g/100 g, 8.41 g/100 g, and 1.86 g/100 g respectively. Highland barley flour contained 17 amino acids, and the contents of total amino acid were 9.471 g/100 g. The optimum preparation of extrusion puffed conditions were determined as follows: barrel temperature of T2 to T6 were 60, 140, 140, 80, 50 ℃, feeding rate 50 kg/h, screw speed 280 r/min, and moisture content 23%. The optimum preparation of pre-drying conditions was determined as follows: drying temperature 60 ℃, air volume 12%, drying time 16 min, material thickness 30 mm. The optimum preparation of roasting conditions was determined as follows: surface fire 180 ℃, bottom fire 220 ℃, time 70 s. Under the control of these conditions, the gelatinization degree of extruded puffing highland barley flour was 98.73%, and highland barley chips had good quality with good taste, color, aroma and appearance.

Abstract:In order to explore the quality change characteristics of sweet potato leaves during salinization, ultrasonic, and their combined pretreatment, the physicochemical properties of sweet potato leaves during heat pump drying under different pretreatment processes were studied. The results showed that when the POD enzyme after drying was low in suitability and strong in antioxidant capacity, with 4% of salt concentration, Under the control of these conditions, the rehydration of sweet potato leaves was generally higher than that of others. Moreover, the drying time was the shortest and the comprehensive score was the highest.

Abstract:In order to solve the problem of poor sensory quality caused by the high content of starch and protein in tobacco leaves, a method for degrading starch and protein without affecting the workability of tobacco leaves was investigated. In this study, formic acid was used as catalyst to spray proper amount on tobacco leaves. The hydrolysis of starch and protein in tobacco leaves catalyzed by formic acid, which played an effective role in regulating and reducing the starch and protein content. When the concentration of formic acid ranged from 5% to 10% at 50 ℃, with the sprinkling rate of 0.2 mL/g formic acid solution to the tobacco leaves, the appearance quality and microstructure of tobacco leaves were unchanged significantly, and the workability was still fine. The results of FTIR spectrum presented that the peak intensity of characteristic functional groups of starch and protein in tobacco leaves decreased obviously after formic acid treatment. The starch and protein of tobacco leaves could be effectively degraded by formic acid, and the degradation rate was positively correlated with the concentration of formic acid. The hydrolysate of protein is polypeptide and amino acid, and the hydrolysate of starch is polysaccharide and monosaccharide, which can transform into aroma components by Maillard reaction. The results of sensory evaluation showed that the tobacco treated by appropriate concentration of formic acid had less taste impurity, more aroma and better quality.

Abstract:The influence of cargo stack, air supply velocity, air supply form, the fan position and other factors on the temperature distribution of refrigerated containers is reviewed, and the spatial distribution characteristics of the temperature field in the container are also expounded. The relevant factors affecting the temperature distribution in the container are compared and analyzed, and its future development direction is prospected.

Abstract:This review summarizes the latest research of chitin in food field, including the application of chitin film as food packaging materials, the application of chitin microspheres in immobilization, adsorption and separation of macromolecules, the preparation of nano chitin and its application in emulsification, regulation of food texture, antibacterial function, and health promoting effect, the new method for preparing chitin oligosaccharides.

Abstract:In this paper,the extraction and application of protein, polysaccharide, polyphenol and tea saponin from Camellia oleifera cake were reviewed. It is found that Camellia oleifera meal has high processing and utilization value, which can be used as new food raw material or feed, chemical industry, light industry and other important raw materials. On the whole, the by-products of Camellia oleifera have certain potential in the development and application direction of special medical food and health food.