Abstract:The millet flour, which was treated at different heat treatment temperature, was mixed with wheat flour. The millet flour was 20% in the mixed flour. The optimum process conditions to improve the quality of the mixed flour was determined by detecting the characteristics of the mixed flour and sensory evaluating the steamed bread which was 110℃,15min.The effect of the different proportion of heat treatment millet flour on the mixed flour was studied. The experiment indicated that heat treatment can significantly improve the viscosity of millet flour, significantly reduce the hardness and improve the quality of steamed bread. Sensory evaluation had concluded that the quality of steamed bread can notably improved when adding 10% heat treatment millet flour.

Abstract:The effect of different proportion （0.1%、0.3%、0.5%和0.7 %）of sodium alginate on frozen dough bread baking properties was studied. The results showed that after adding sodium alginate, the water holding capacity of the frozen dough, specific volume and elasticity of the bread was increased, while the proofing time of the frozen dough, the hardness and chewiness of the bread was decreased, showing that it could improve the quality of frozen dough bread. The bread with 0.3% addition of sodium alginate frozen for days had the highest sensory score according to sensory evaluations.

Abstract:The effect of different soaking time on polyphenol, flavone, DPPH scavenging activity, ABTS+·scavenging activity and total antioxidant activity of mung beans soaking solution was studied, and the correlation between polyphenol, flavone and antioxidant activity was also analyzed. The results showed that the contents of polyphenol and flavone increased rapidly and DPPH scavenging activity, ABTS+·scavenging activity increased significantly along with the increase of soaking time within 4~12 h. The increasing rate slowed down gradually till no obvious changes after 12 h. The total antioxidant activity increased rapidly with the increase of soaking time within 4~8 h, then maintaining slow growth and the activity reached maximum when soaked for 24 h. The contents of polyphenol and flavone were significantly correlated to antioxidant activity (P<0.01).

Abstract:Response surface methodology was used to optimize process parameters for the extraction of brown pigment from chestnut shell based on extraction rate. A regression model equation was fitted. The result showed that the optimum extraction condition was, the ratio of material to liquid 1∶30, extraction temperature 73 ℃, concentration of ethanol 40% and extraction time 2.45 h. The extraction rate of brown pigment from chestnut shell was 6.55%. The regression model had excellent fitting, can be used to the actual operation.

Abstract:Cereals bar is a type of new snack food, containing oats, rice and other cereals as main raw materials mixed with nuts, dried fruits and other accessories, conglutinated with high viscosity syrup into sheet or rod shape. The formula and processing technology of cereals bar products were reviewed, and its development trend was prospected in view of the features of cereals bar on the market and consumers hobby.

Abstract:The microwave assisted extraction of phytosterol from rapeseed oil was optimized by orthogonal experiments based on single factor experiments.The results showed that under the condition of microwave temperature 50 ℃, microwave time 1 min, microwave power 200 W, the ratio of material to liquid 1∶12, the extraction amount was the highest, reaching to 2.265 mg/g. The antioxidation of the crude sterol extracted from rapeseed oil under the optimized condition was determined by studying the ability of scavenging hydroxy radicals(·OH). The result showed that crude sterol from rapeseed oil had strong antioxidant activity.

Abstract:The quality change of sunflower oil, which was rich in oleic acid and linoleic acid, during frying process was explored. The results showed that: sunflower oil fried for 24 h at190±5 ℃, the acid value increased from 0.26 mg/g to 0.89 mg/g, peroxide value increased from 4.40 mmol/kg to 8.20 mmol/kg, carbonyl value rose from 8.39 meq/kg to 74.47 meq/kg, the content of malondialdehyde rose from 0.25 mg/100 g to 2.07 mg/100 g, the content of total trans-acids increased from0.45% to 1.40%, the content of vitamin E reduced from 39.52 mg/100 g to 14.23 mg/100 g and polar component rose from 3.80% to 35.30%. Among the results, carbonyl value reached to 44.44 meq/kg when fried for 12 h and the content of polar component reached to 26.70% when fried for 18 h, which was close to the index in GB 7102.1—2003 Hygienic standard for edible vegetable oils during frying. So, sunflower oil is not suitable frying food at high temperatures for a long time. And the frying time should be less than 12 h.

Abstract:The global development trend, chemical composition and characteristics of rice bran oil were reviewed. The content changes of γ-oryzanol, tocopherol and other micronutrients, and their distribution in residues during rice bran oil refining were reviewed. The influence of γ-oryzanol, tocopherols, phytosterol and their complexes on oxidation stability of rice bran oil was discussed.

Abstract:In order to evaluate the appearance quality of cooked rice accurately，the appearance eigenvalues of cooked rice was measured by image processing technology, the correlativity between eigenvalues and sensory evaluation was investigated. The results showed that the difference in variety of indica rice was bigger than japonica rice,and the subjectivity existed by sensory evaluation. There was a good correlation between test indicators based on image processing technology and sensory evaluation of cooked rice. The regression equations and the regression coefficients which were built by various sensory evaluation indices(as dependent variables) reached significant level, and the predicted results were consistent with the results from sensory evaluation, the fitting degree between predicted value and sensory score was high up to 97.6%. So appearance sensory evaluation can be replaced partly by image processing technique to evaluate the appearance of cooked rice accurately.

Abstract:The extraction of polyphenols from B. blakeana Dunn leaves by ultrasonic-assisted extraction was optimized. Based on single factor experiments, ratio of liquid to solid, ethanol concentration and pH were selected as independent variables，and the yield of polyphenols as response value, the experiment method was designed according to Box-Behnken central composite design with 3 factors and 3 levels, the effects of each independent variables and their interactions on the yield of polyphenols were studied. The mathematical regression model of the yield of polyphenols and each factor was established by using the Design-Expert software and the optimum condition was determined. The results showed ethanol concentration was the most significant factor to affect response value. The modified optimum extraction condition was ratio of liquid to solid 37∶1, ethanol concentration 74%, pH 6. Under the condition, polyphenols yield was 1.47%, which was basically the same as predictive value of 1.49% by the model, which meant the optimization of the extraction of the polyphenols from B. blakeana Dunn leaves by response surface methodology was reasonable and practicable.

Abstract:Vitamin B2 microcapsule was prepared by spray-drying technique using arabic gum as wall material and vitamin B2 as core material. The effects of technological parameters, including ratio of wall to core, wall material concentration, inlet temperature and feeding rate, on microencapsulation efficiency were investigated. The optimal microencapsulation condition was obtained by single factor and orthogonal experiments which was ratio of wall to core 10∶1, the concentration of wall material 20%, inlet temperature 170 ℃, and feeding rate 3 mL/min. Under the optimum condition, the vitamin B2 microcapsule embedding rate reached to 86.12%.

Abstract:The detection methods of elements in grain and related standards in our country were sorted out. The sample pre-treatment and detection methods were compared and analyzed. The problems in detection methods were discussed. The further development on pre-treatment in detection of elements in grain was prospected. The purpose was to help related inspector realize the detection methods and providing a reference for the recension of the related standards.

Abstract:The aflatoxinsB1（AFB1）in agricultural products was treated by low temperature radio frequency plasma and the degradation rate of AFB1 was analyzed by HPLC. The results showed that the effect of plasma treatment on degradation of AFB1 in agricultural products was significant. The degradation rate of AFB1 in peanut and corn reached to 88.3% and 92.2% respectively, by plasma treatment of 150 W for 500 s. AFB1 could be degraded more completely with transmit power and radiation time increasing. There was considerable difference in the degradation of AFB1 with different particle size of poisonous products under the same plasma conditions. The degradation rate of AFB1 in granular mixed peanut and corn sample were lower than that in powder.

Abstract:A closed microwave digestion- ICP-MS method was established to determine simultaneously As, Pb, Hg, Mg, Al content in nuts and fruit and vegetable seed kernel. The samples were digested with microwave digestion instrument and analyzed by inductively coupled plasma mass spectrometer, 72Ge as an internal standard of As, 209Bi as an internal standard of Pb and Hg, 45Sc as the internal standard of Mg and Al to control the dynamic drift of the analytical signals, As, Pb, Hg, Mg, Al content in nuts and fruit and vegetable seed kernel were determined simultaneously. The results showed that the recoveries of As, Pb, Hg, Mg, Al between 95%~105%; the detection limits of them were 0.005 mg/Kg, 0.005 mg/Kg, 0.001 mg/Kg, 0.01 mg/Kg, 0.005 mg/Kg; all of the linear correlation coefficient more than 0.999 9; RSD less than 2%. The results, recovery, detection limit, accuracy and precision, met the requirements of the determination of As, Pb, Hg, Mg, Al content in nuts and fruit and vegetable seed kernels, which provided a basis for quality standards of nuts and fruit and vegetable seed kernel.

Abstract:The method for determing methenamine in yuba was set up. The sample was extracted by acetonitrile. Methenamine was hydrolyzed into formaldehyde by hydrochloric acid. The formaldehyde can be reacted with 3-methyl-2-benzothiazolinone ketone hydrazone hydrochloride (phenol reagent) and ferric ammonium sulfate to form a blue-green compound, which can be measured by spectrophotometry at 630 nm after degreasing by neutral alumina. Some effect factors of experimental conditions were investigated like the amount of hydrochloric acid, hydrolysis temperature, adsorbent category and adsorption condition, reaction time and so on. The result showed that the determination was not interfered by fat, sugar, protein and phenylalanine, while slightly interfered by sulfite, which did not affect the determination conclusion. The method showed a good linearity at the range of 0.6～6.0 μg/mL of methenamine. The average recovery was 88.2%. The method is sensitive, and can be used to detect methenamine in yuba.

Abstract:According to the different samples using different extraction methods, fat-free food samples were extracted by n-hexane, oil samples by ethyl acetate: cyclohexane (V/V=1), fat- containing samples by petroleum ether, ethyl acetate and cyclohexane jointly. Each extract was concentrated to 2mL, determined by gas chromatography-mass spectrometer. The result showed that the recovery rate of rapid determination of phthalates plasticizer was 85.9%~110.2%, RSD was 1.87%~5.89%.

Abstract:The research progress in detection of toxicity of phthalic acid ester was summarized, including the reproduction and development toxicity, embryo toxicity, tumours and carcinogenesis, sample treatment and instrument analytical method.

Abstract:The effects of 3 kinds of pretreatment, acid hydrolyzation, enzymatic hydrolyzation and acidification enzymatic hydrolyzation, on the detection of the content of premna microphylla leaves pectin by ion chromatography were studied. The esterification of galacturonic acid with different amount of acidic solution was also studied. 26% galacturonic acid was remained after reacting in 2 mol/L HCl for 12 h. The result was a little low by acid hydrolyzation with 2 mol/L HCl. The pectin accounting for 1.06%~3.78% of the total weight of the leaves was remained without being hydrolyzed after enzymatic hydrolysis with 400 mg pectinase for 4 h. The leaves were acidified with 0.05 mol/L HCl, and the dilute acid extract liquid and the residues were enzymatic hydrolyzed with 10 mg pectinase respectively. The result using acidification enzymatic hydrolyzation was 29.34% higher than that using the acid hydrolyzation, and 12.45% higher than that using the enzymatic hydrolysis, without esterification and with less amount of pectinase. The ion chromatography had good linearity with a correlation coefficient of 1.000 0, while the detection limit for galacturonic acid was 4.05 μg/L. The recovery of pectin in different premna microphylla leaves was above 95%, and the relative standard deviation (RSD) was less than 5%.

Abstract:The effects of temperature, pH, substrate concentration, enzyme concentration on soy protein hydrolyzed by papain were researched with the degree of hydrolysis as indicator through single-factor and orthogonal experiment. The condition was optimized. The result showed that the order of the factors effecting the hydrolyzation was temperature, pH, enzyme concentration and substrate concentration. The optimized parameters were temperature 60 ℃, pH 7.5, enzyme concentration 3.5%, substrate concentration 5%. Hydrolysis for 40 min under the optimized condition，the degree of hydrolysis of soy protein by papain could reach to 6.58%, the average number of amino acids of soybean peptide was 15, and the average molecular weight was 1 875.

Abstract:The soybean milk beverage was prepared by fermentation of fibrinolytic enzyme strains with soybeans. The parameters of the beverage were determined preliminaryly by single factor experiments, they were : inoculum size of 7%, fermenting for 72 h at 37℃. The optimal blending parameters were, by orthogonal experiment, sugar 9%, mixed emulsifier (monoglyceride: sucrose ester=1∶1) 0.15%, carboxymethyl cellulose(CMC) 0.1%, propylene glycol alginate (PGA) 0.2%, the beverage had the best taste when it was stored at 4 ℃ for less than 5 days.

Abstract:Exopolysaccharides (EPS) are natural biological polymers which are excreted outside the cell wall and infiltrated into the medium during lactic acid bacteria(LAB) growth and metabolism. It has been becoming a research hotspot recently because of its important physical properties and physiological functions, such as reducing cholesterol, antitumor, promoting thalli adhesion to intestinal mucosa, immune response and being used in foods as thickener and stabilizer. It is extremely significant to study its biosynthetic pathway, structure and structure-activity relationship for improving the EPS yield and understanding the correlative mechanism. The classification and biosynthesis mechanism of EPS, as well as their structure- activity relationship and biological activity were summarized.

Abstract:The quality change of rice with high moisture content during store at low temperature was studied by the test with japonica rice from northeast China. The results showed that the rice with the initial moisture content 17.54% would maintain moisture content of 16.0%, fatty acid value less than 25 mg KOH/100g when it was stored at below 15 ℃, relative humidity 60%~70% for 10 months, which had no obvious quality deterioration and was in the range of suitable storage. During the storage, L value was reduced, b value increased, a value had no obvious regularity. The analysis of TPA quality and structure for cooked rice showed that the hardness increased, the viscosity and elasticity descended, cohesion increased. After 6 months, the indicators changed obviously. In summer the rice with high moisture content stored for 1 month mildewed after removed from low temperature. The moisture content, fatty acid value and color difference altered obviously. The result determined by scanning electron microscopy showed that along with the extension of storage time the crack on the surface of the rice kernel was enlarged, starch grains were exposed and embryo part formed hollow. The pores on the endosperm cell surface increased in size and number, the boundaries between the wrapped composite amyloid become blur and protein membrane obviously cocked.

Abstract:The formula for operation condition of mechanical ventilate was established based on atmospheric saturation absolute humidity, grain temperature, equilibrium relative humidity and the related data of grain moisture. It provided mathematical basis for real-time monitoring of mechanical ventilation work.

Abstract:The insecticidal effect of domestic developed mobile duster and food-grade inert dust on five major species of stored grain imago, Rhizopertha dominica (Fabricius)，Sitophilus zeamais (Motschulsky)，Oryzaephilus surinamensis (Linné)，Tribolium castaneum (Herbst)，Cryptolestes ferrugineus（Stephens）, operating empty grain storehouse, was tested in order to solve the problems, such as poor effect，insect resistance，and harm to operators. The results showed that the duster possessed good spraying effect with uniform dispersion of dust without obvious difference inside of the grain storehouse, the mortality rate of the store pests in the test reached 100% in 3 days．

Abstract:Trapping technology as one of the important non-chemical means had been broadly used in pest monitoring and control, which was received widespread attention at home and abroad. The research progress in trapping technology based on the physiological characteristics and habits of pests, such as sight, smell and pheromones was summarized, which provided help for further research on trapping technology and their application.