Abstract:Poly(butylene succinate) (PBS)/starch film was prepared by in situ plasticization of glycerol and H2O, then blending PBS with corn starch wetly, and finally extrusion casting. SEM observation showed the starch using the mix of water and glycerin as plasticizer could be dispersed evenly in the matrix of PBS, the compatibility between starch and PBS was improved evidently due to the in situ plasticizing of starch, and the comprehensive mechanical properties of the film were enhanced comparing with dry starch packing modification. The highest tensile strengths both in length and breadth of the film could be observed when starch content was 115% and the ratio of glycerol to H2O was 1∶2. Comparing with the neat PBS film, elongation at break in length and breadth increased by 1472% and 513%, and the right angle tear strength in length and breadth increased by 1608% and 573%, respectively. Both the tensile strength and angle tear strength decreased with the increase of starch content. The highest break elongations both in length and breadth could be obtained with a starch content of 30%. The biodegradable films were suitable for practical application and could meet the requirement of GB/T 4456-1996 even with the high starch content of 25% and 30%.

Abstract:The changes in the properties of food packaging materials under high-pressure processing (HPP) in recent years were reviewed in this paper. The properties of packaging materials including structure, barrier property, mechanical property, sorption behavior, and migration of components were described. The development trend and research emphasis in future were also briefly discussed.

Abstract:The volatile components of beef flavor were extracted by thermal desorber (TD), solid phase micro extraction (SPME) and simultaneous distillation extraction (SDE), respectively, and then analyzed by GC/MS. The results indicated that the selectivity of the three extraction methods was different. Therefore, the three methods should be combined to obtain the entire information of the flavor components.

Abstract:The conditions of bio-transformation of methionol by Saccharomyces cerevisiae SC408 were studied. The optimal culture conditions were obtained as follows: amino acid of 40g/L, KH2PO4 of 80g/L, K2HPO4 of 60g/L, MgCl2 of 001g/L, FeCl2 of 002g/L, ZnSO4 of 003g/L, yeast extract of 08g/L, glucose of 300g/L, NaCl of 20g/L, temperature of 30℃ and shaking rate of 200r/min. The maximum yield of aimed product under the optimal conditions reached 16g/L at 132h and the transformation rate was 72%.

Abstract:Propolis has strong antimicrobial activity, and is often used as drugs or health products. Twenty nine different propolis from 23 provinces of China were selected and studied in this paper, which were further classified into five groups according to the climate zone where collected. The size of inhibition zone and minimum inhibitory concentration (MIC) of 9 different strains (Staphylococcus aureus, Bacillus subtilis, Aerobacter aerogenes, Escherichia coli, Proteus, Penicillium, Aspergillus, Mucor, Rhizopus) by the ethanol extract of different propolis (EEP) were measured. The results showed that EEP had good antimicrobial activity against Gram-positive bacteria, Gram-negative bacteria and fungi. The average inhibition zone diameter of Gram-positive bacteria, Gram-negative bacteria and fungi were 988mm±147mm, 875mm±156mm and 1001mm±065mm, respectively. EEP exhibited the highest antimicrobial activity against fungi, while the lowest activity against Gram-negative bacteria. The results indicated that the antimicrobial activity of EEP had no significant correlation with their climate zone.

Abstract:The effects of substrate concentration, pH, temperature, enzyme dosage, accelerant of enzymatic hydrolysis and time on the hydrolysis of soybean powder by the combined enzymes of Alcalase and papain were studied in this paper. The optimal conditions of enzymatic hydrolysis were obtained by using one-factor and orthogonal design, which were as follows: substrate concentration of 45%, combined enzyme dosage (the ratio of Alcalase to papain 2∶1) of 2640U/g, 5mmol/L of Mn2+, pH 85, 60℃, and reaction time of 180min. Under the optimal conditions, the degree of hydrolysis (DH) could reach 178%.

Abstract:The structure of konjac, konjac-graft-acrylic acid (AA), and regenerant of graft were studied with scanning electron microscope(SEM). The effect of grafting, regenerating and urea loading on konjac structure were discussed. The results showed that the konjac’s piece structure were transformed into grafter’s dense network structure by grafting, the grafter’s dense network structure was transformed into regenerant’s tussocky structure by regeneration, and the grafter’s structure was transformed into thick network by urea loading and the urea was filled in the hole. The urea absorbility of grafter was not influenced by the concentration of urea solution. The urea content of the swollen gel showed a linear relationship with the concentration of urea solution (R2=09998).

Abstract:Total volatile basic nitrogen (TVB-N) value is a recognized national standard for evaluating physical and chemical indicators of meat freshness. In this paper, the measurement uncertainty for the amount of TVB-N in fresh meat was evaluated using semi-micro method of Kay’s fixed nitrogen in order to accurately measure the volatile basic nitrogen content of the fresh meat and assess the freshness of meat objectively. The evaluation result indicated that the major factors of uncertainty were the actual consumption volume of hydrochloric acid for sample solution and the repeatability of measurement outcome.

Abstract:There is no national standard yet for measuring anthocyanins of purple tea leaves. The methods for determining Anthocyanins of tea leaves by single-pH and pH-Differential spectrophotometry were compared in this paper. The results indicated that anthocyanins content measured by single-pH was much more than that measured by pH-Differential spectrophotometry. The two methods had good linear relation (R2=09927). The effects of interfering substances on quantitative analysis of anthocyanins could be eliminated by using pH-Differential spectrophotometry. The results provided a reliable basis for the measurement of anthocyanins.

Abstract:The microwave-assist extraction of pectin from potato starch residue was studied in this paper. The effect of the ratio of liquid to material, pH values, microwave heating time, microwave power and the dosage of aluminum sulfate on the pectin extraction were investigated. The optimized extraction conditions were obtained as follows, the ratio of liquid to material of 15∶1, pH 2, microwave heating time of 5min, microwave power of 04kW, and the dosage of aluminum sulfate of 7mL. The extraction rate of pectin was 18537% under the optimal conditions. The microwave-assist extraction showed many advantages over the traditional method in shortening time, saving solvent and the high yield.

Abstract:The close-loop control in the MSG wastewater treatment system based on three-phase biological fluidized bed was studied in this paper. A nonlinear model predictive control method based on ANN was established considering the characteristics of large time-delays and complex nonlinearity. First the chemical model of MSG wastewater treatment process was built up. Next the model was modified by using the nonlinear model predictive control method. Then the sequential quadratic programming method was employed to tackle the constrained high nonlinear programming problems. Finally the close-loop optimal control system was realized. Simulation experiment results showed that this method was effective and could realize the closed-loop real-time control which would have a broad prospect of application.

Abstract:A food safety surveillance model based on the Internet of things technique was constructed from the perspective of food processing. The model was used to test and monitor the toxic materials which were harmful to human life, and also used to evaluate comprehensively the possibility of risk causing unsafe factors in food production. By analyzing the food safety surveillance model, an effective food safety surveillance system was established to diminish the hazard of food safety problem to the highest extent in order to ensure the safe food supply.

Abstract:The current situation of Chinese food safety regulation was analyzed in this paper. Chinese food safety regulation was faced with dual challenges of the traditional and unconventional food quality and safety problems, such as the food regulatory interest subjects’ out-of-control behavior, the uneven development of food industry, genetically modified food, environment pollution, and so on. However, at present, the segmented food safety regulation system in China, the weak food safety monitoring infrastructure, the relatively backward inspection means, and the rapidly aging team are not adapted to the requirements of food safety regulation. The urgent need of the food safety regulation in China is to establish a national special food safety regulation department, perfect the legal system of food safety regulation, set up the food industry trade credit archives, and implement the food quality and safety traceability system as fast as possible.

Abstract:Xylanases have drawn attention widely in recent years as they play important roles in food, feed, and paper industry. Efforts on costs reduction of xylanase preparations have been directed towards increasing enzyme production by developing better microbial strains, suitable xylanase inducers and efficient fermentation techniques. Thus many microbes which can produce xylanases directly on lignocellulose have been selected. The research status of xylanase-producing microorganisms from lignocellulose materials available was reviewed in this paper.

Abstract:Mutton is a kind of common food in the world which has no religious and cultural taboos. Mutton industry has developed rapidly and commercial production of mutton essence has been carried out in China. In this paper, the precursors of meat flavor, chemical reaction for producing the flavor, the mutton flavor compounds, basic production model of mutton essence were reviewed, which would provide the reference for further research and application of mutton flavor.

Abstract:The cam-gear-linkage combination mechanism was used in the new model thread-taking-up mechanism of computerized embroidery machines. The calculation model of the thread-taking-up location accuracy analysis was established by using mechanism analysis method. The thread-taking-up accuracy of the thread-taking-up mechanism was analyzed in detail. The numerical differentiation formula for thread-taking-up accuracy was obtained, the MATLAB computer program is developed, and a practical calculation has been made of the new thread-taking-up mechanism. The rule of thread-taking-up accuracy along with the change of the crank angle was presented, which has provided a very important reference for mechanism kinematics design in thread-taking-up mechanism of computerized embroidery machines as well as for enhancing the embroidery quality.

Abstract:The structure characteristics of high speed motorized spindle for wood-working machines are introduced and the mechanism of thermal deformation of motorized spindle is analyzed. The finite element analysis model of high speed motorized spindle for wood-working machines thermal characteristics is built. The static temperature field is calculated using software ANSYS. The real working conditions are simulated by step loaded transient thermal analysis and the temperature rising trend is got which can be used for temperature control of motorized spindle. By the result of simulation, the main measures to improve the thermal characteristic of the high speed motorized spindle for wood-working machines are put and references to structure design of motorized spindle are offered.