Chitosan was chemically modified in different ways to probe their properties when used in soaping agents for reactive dyeing.The experiments showed that chitosan derivations(N, O-CMCTS & NAOC)could remove effectively the loose color in the reactive dyeing to increase the soaping effect in reactive dyeing.Both of N,O-CMCTS and NAOC had good water-solubility and resistance to hardness of water.The first work of this paper is measuring physical properties of chitosan.Degree of deacetylation(DD)of chitosan determined by acid base titration is about 83%.The MW of chitosan by viscometry is about 1.0×10~5.The effect between chitosan derivatives and hydrolyzed reactive dyes was also studied.The result showed that the stability of micelles composed by NAOC and hydrolyzed reactive dyes was sensitive to its concentration.The soaping effect of both derivatives could hardly be affected by increasing their concentration due to the balance between chitosan derivatives and hydrolyzed reactive dyes.At the same time the conditions affect on the soaping effect of N,O-CMCTS and NAOC,such as the existence of inorganic salt and alkaline, complexation with anionic/nonionic surfactants,have been discussed in detail.The result shows that NAOC had stronger salt-resistance than N,O-CMCTS;the complexation of N, O-CMCTS/NAOC and nonionic surfactant had slightly better soaping effect than that when used separately;while the soaping effect of NAOC was remarkably removed by complexation with anionic surfactant.At last,the concentration of chitosan derivatives,the soaping temperature,time,and pH,et al.were studied when used in soaping agents for reactive dyeing respectively.On the base of experience of above experiment,the reaction conditions of chitosan derivations were systematically investigated through orthogonal design,and then the best conditions were found.N, O-CMCTS:0.50 g/L,90℃,20min,pH=10;NAOC:0.250 g/L,90℃,20min, pH=9.Compared with one of market soaping agents,N,O-CMCTS and NAOC could raise the friction degree and soaping degree by about 0.5 degree.
Handicraft of Light Archive
Studies on Fermentation and Antibacterial Characteristics of Compounded Ferments in the Imitated Mares Milk
Eleven strains of Lactic acid bacteria and four strains of Yeasts isolated from samples of koumiss collected from heardman,s house in Inner Mongolia were studied. Three restore ferments compounded from the same area’s sample and three crossing ferments compounded from the different area’s samples were obtained. The lactose contents of three kinds of imitated mare’s milk (P1:6.0g/100ml, P2:6.5g/100ml and P3:7.0g/100ml) produced by mixing of whole cow’s milk and demineraled whey at proper proportion were similar to that of mares’ milk. Through 72h fermentation by two restore ferments, results suggested four kinds of whey showed antibacterial property.But there were not significant differences of nature of antibacteria among them. Considering cost, two kinds of imitated mare’s milk (P1, P2) were chosen for further study. Inhibit property of three restore ferments and three crossing ferments were screened under the selected culture ( P1 , P2 ) , with culturing temperature of 28 ℃ ~30 ℃. Two restore ferments (a1, a3) and two crossing ferments (b2, b3) were identified from the six ferments. Then through changing culturing temperature to 37 ℃, two crossing ferments (b2, b3) with optimum antibacterial activity were obtained. Study on their inhibit property indicated that the greatest antibacterial activity showed during 48h in P1 by the two crossing ferments fermentation, and showed during 18h~22h in P2.The antibacterial activity of four kinds of whey were affected significantly by concentration, temperature and pH value. The thicker of whey, the stronger their antibacterial activity changed. As pH increasing, the higher temperature, the more the losses of antibacterial activity.
In this paper, oxidized starch by KMnO4 on the condition of acidityis studied.KMnO4 oxidization method has the advantages of high oxidativedegree, simple operation and low environmental pollution, so oxidizedstarch by KMnO4 has broad prospects.The research finds, in the process of KMnO4 oxidizing starch on thecondition of acidity, that it is activated manganese dioxide but notpotassium permanganate that directly oxidizes starch. This mechanismsuccessfully explains the essence that the color of the emulsion changesin the process of KMnO4 oxidizing starch. Based on that theory, theactivation energy of oxidization process is calculated at 73.83kJ/mol.Meanwhile, a variety of factors that affect oxidized starch byKMnO4 are studied in this paper, including the temperature and theconcentration of KMnO4, H2SO4 and starch milk, and theoretically probesall kinds of influences.The experimentation proves that the speed of the reaction willincrease when the temperature rises, the speed of the reaction willincrease 2～3 times whenever the temperature raises 10℃, and thechanges of temperature have little effect on the carboxyl content ofoxidized starch. If the dose of H2SO4 goes up, the carboxyl content ofoxidized starch will increase, the reaction time will shorten, but the fieldsof the oxidized starch will decrease. If the concentration of KMnO4 rises,the carboxyl content of oxidized starch will increase, the speed of thereaction will increase, but the fields of the oxidized starch will decrease.The higher the concentration of starch is, the bigger the speed of thereaction is, but the concentration of starch has little effects on thecarboxyl content of oxidized starch.The most proper conditions of KMnO4 oxidizing corn starch are thatthe concentration of starch is 35%, that the amount of KMnO4 is 4% ofstarch, that the amount of H2SO4（98%） is 1.28 times of KMnO4, and thatthe temperature of the reaction is 55℃. The time of complete reaction isabout 70 minutes on those conditions. In addition, the analysis method of the carboxyl content of oxidizedstarch is still studied. It finds through experimentation, that thecoordination titration method is more accurate and simpler than thetraditional starch paste method.The oxidized starch has been widely used in many industrial fields,such as paper, textile and food. This paper summarizes its application,and some compared experimentations have been done for the applicationof the oxidized starch by KMnO4 in paper and corrugated paper adhesive.The new development of the application of the oxidized starch isintroduced in this paper.
In this paper, it was reviewed that development tendency of anti-crease finishing agents on natural fabrics at home and abroad. Preparation, finishing condition and effect of environmental fabric finishing agent of silk fibroin on natural fibers are studied emphatically.The silk fibroin can be swelled firstly by CaCl2 , then decomposed by acid or enzyme. The lower molecular weight of silk fibroin after being hydrolyzed can be used with soluble cross – linked agent PU to cotton fabrics and with organic silicon to silk fabrics in order to increase anti-crease property.Comparing the three methods of preparing silk fibroin finishing agent, we concluded that the method with acid is the best. Cotton and silk treated with this kind of finishing agent were analyzed .The results showed.that the treated fabrics with this new agent had better crease resistance than that of the fabrics treated with conventional agents, in addition, showed better strength, softness moisture absorption and so on.Fibroin finishing agent is a kind of finishing agent without pollution and can be decomposed by microorganism. The assistant agents used in this finishing process can also be decomposed by microorganism in some degree. we can conclude that the Fibroin finishing agent is the most competitive agent in the 21 century.
Conformation and Functional Properties of Wheat Gluten Hydrolysate/Polysaccharide Conjugates Synthesized by Ultrasound
Wheat gluten is a byproduct of the wheat starch industry. The use in food is limited by its water-insoluble characteristic. The aim of the present study was to modify wheat gluten by graft reaction of gluten hydrolysate and polysaccharide subjected to ultrasound treatment for improving its functional properties and extending utilization. Optimal technological conditions and some rules of functional properties of the modified glutens changing were studied. Relation of composition/structure of the modified glutens to functional properties was analyzed. Moreover, the conjugates were also used in the milk emulsions.Two proteases (Protamex and Papain) were used to hydrolyze gluten protein. The conditions of graft reaction of gluten hydrolysate and polysaccharide were optimized. In single factor experiments, the effects of the degree of hydrolysis, weight ratio of polysaccharide to gluten hydrolysates, reaction time and pH value on the degree of graft reaction (DG) were investigated. Optimal conditions of gluten hydrolysate and Arabic gum for graft reaction were obtained by surface response design. The conjugate with the highest degree of graft(DG=23.56%) using DH8.8% of Protamex hydrolysate and Arabic gum could be obtained, when the most optimum conditions were as follows: the weight ratio of protein to polysaccharide 10:1, time 19min, pH9.2, temperature 80℃.The functionality of conjugates of Protamex hydrolysate and Arabic gum was studied. Solubility, thermal stability, emulsifying and foaming properties of the resultant conjugate were significantly (P<0.05) improved compared the hydrolysate and control. Solubility curve kept relatively plateau at pH3-10. No obvious pI was noticed. Nitrogen Solubility Index (NSI) was about 30% increases in acidic condition compared to the control. Emulsifying Stability (ES) had a clear improvement; it was about 2.7 times of the control when DG is the maximum. Foam Stability (FS) in acidic condition was about 3.2 times of the control when DG is 14.8% and FS reached maximum.In secondary structure based on FT-IR, modification led to decrease and increase inα-helix andβ-structure ratio, respectively. The conjugate had the lowestα-helix/β-sheet ratio and the highest molecular flexibility. Microstructure of the modified glutens had great change based on SEM observation. The conjugates had less edges and corners than control. According to SDS-PAGE analysis, new broad bands of the conjugate subunits compared to control appeared in the upper regions of the separation gel and the glycosyl bands were seen more clearly. These illustrated macromolecular grafts emerged. Change in molecular weight distribution and structure of the modified gluten proteins resulted in improvement of flexibility and surface properties. These changes play an important role in improvement of functional properties.The conjugates were used as partial substitute for sodium caseinate in the imitated neutral emulsions. It was an effective replacer to slow down enlargement of the d3,2 at the top and bottom of emulsions, creaming rate and centrifugal sedimentation rate when replaced about 10%-30% of the sodium caseinate. The imitated acidic emulsions showed low creaming rate and centrifugal sedimentation rate when conjugates were used as skim milk powder replacer in the emulsions to replace about 30% or 40% of the skim milk powder.
Effect of Mild Heat Pre-treatment on Cold Storage Quality in Fresh-cut Chinese Water Chestnut (Eleocharistuberose Schult)
Fresh-cut Chinese water chestnut （Eleocharistuberose Schult） （CWC） is mechanical injuried after minimumlly processed. There will be more physiological and biochemical reactions unbenefited for fruit storage, which can make fruit quality deterioration and shorten fruit shelf-life. Mild heat pre-treatment （MHPT） is non-toxic, efficient, economic, safe and harmless to the human and environment, which may be concerned by more and more people recently.In this paper, the fresh-cut CWC were treated by heat water combined with modified atmosphere package, and a central composite rotation designed combine response surface methodology also used in the experiment design. The effects of heat treatment time, temperature and storage time on storage quality and nutrition content of fresh-cut CWC were studied in the paper. The treatment which can best inhibit fruit browning （58℃, 20 min） were used to anlysis the browning index （BI）, total phenol （TP） and flavonoid content, phenylalamine ammonialyase （PAL） activity, which may explain anti-browning mechanism in fresh-cut CWC by heat treatment. Meanwhile, we evaluated the fruit sensory quality with quantitative descriptive analysis and principal component analysis on the best anti-browning treatment. The results were as follows:1. Effect on fresh-cut CWC quality by MHPT（1）The model of DYI was Y=737．1416-24．844*X1-14．08333*X2+138．5307*X3+0．202121*X1*X1+0．454086*X1*X2- 1．607526*X1*X3-0．231567*X2*X2-0．453299*X2*X3-2．022502*X3*X3 Effects on fresh-cut CWC DYI by MHPT were in a significant impact （0.05 level） in factors X1 （heat treatment temperature） and X1 * X3 （the cross-term of temperature and storage time）. When the fresh-cut CWC treated under 54℃in 20 min, and storage for 3 days, the minimum predictive value of DYI was 211.16.（2）The model of DA was Y=-4．88157+0．265497*X1+0．133329*X2-1．880605*X3-0．002684*X1*X1-0．005903*X1*X2+ 0．029531*X1*X3+0．005049*X2*X2+0．002778*X2*X3-0．038961*X3*X3Effects on fresh-cut CWC DA by MHPT were in a significant impact （0.05 level） in factors X3 （storage time）. When the fresh-cut CWC treated under 52℃in 22 min, and storage for 3 days, the optimital predictive value of DA was -1.03.（3）The model of DB was Y=-563．766+11．8074*X1+9．01506*X2+52．20502*X3-0．104083*X1*X1+0．031273*X1*X2- 0．196042*X1*X3-0．253674*X2*X2-0．103056*X2*X3-1．549728*X3*X3Effects on fresh-cut CWC DB by MHPT were in a significant impact （0.05 level） in factors X3 （storage time）. When the fresh-cut CWC treated under 55℃in 20 min, and storage for 3 days, the optimital predictive value of DB was -0.16.（4）The model of BI wasY=-13．12586-0．501611*X1+0．017973*X2+0．62717*X3+0．004278*X1*X1+0．002562*X1*X2- 0．013511*X1*X3-0．003581*X2*X2-0．004117*X2*X3+0．034815*X3*X3Effects on fresh-cut CWC BI by MHPT were in a significant impact （0.05 level） in factors X1 （heat treatment temperature）, X3*X3 （the square of storage time） and X1 * X3 （the cross-term of temperature and storage time）. When the fresh-cut CWC treated under 58℃in 20 min, and storage for 5 days, the minimum predictive value of BI was 0.03.（5）The model of firmness wasY=-4382．3+187．7405*X1+38．52248*X2+90．67424*X3-1．341601*X1*X1+0．122685*X1*X2- 1．385417*X1*X3-1．265478*X2*X2+0．25*X2*X3-4．307243*X3*X3Effects on fresh-cut CWC firmness by MHPT were in a significant impact （0.05 level） infactors X1 （heat treatment temperature）, X3 （storage time）, X1*X1 （the square of heat treatmenttemperature） and X2*X2 （the square of heat treatment time）. When the fresh-cut CWC treated under 64℃in 20 min, and storage for 4 days, the maximum predictive value of firmness was 2509.09N.（6）The model of fracturability wasY=-5026．33+184．2211*X1-17．27665*X2+218．6314X3-1．63926*X1*X1+0．358796*X1*X2- 1．234375*X1*X3+0．309212*X2*X2-0．861111*X2*X3-7．615962*X3*X3Effects on fresh-cut CWC fracturability by MHPT were in a significant impact （0.05 level） in factors X1*X1 （the square of heat treatment temperature） and X2*X2 （the square of heat treatment time）. When the fresh-cut CWC treated under 56℃in 29 min, and storage for 8 days, the maximum predictive value of fracturability was 996.10N.2. Effect on nutrition content of fresh-cut CWC by MHPT（1）The model of ascorbic acid （AsA） wasY=2．147926+0．042608*X1-0．00388*X2+0．049781*X3+0．000053*X1*X1-0．002088*X1*X2- 0．010756*X1X3+0．0027*X2*X2-0．000397*X2*X3+0．038434*X3*X3Effects on fresh-cut CWC AsA by MHPT were in a significant impact （0.05 level） in factors X1 （heat treatment temperature） and X3*X3 （the square of storage time）. When the fresh-cut CWC treated under 47℃in 20 min, and storage for 10 days, the maximum predictive value of AsA is 2.51mg/100g.（2）The model of total solid soluble content （TSS） wasY=95．46889-0．133824*X1-0．135795*X2-7．736579*X3+0．008338*X1*X1-0．036991*X1*X2- 0．082396*X1X3+0．043303*X2*X2+0．046806*X2*X3+0．751542*X3*X3Effects on fresh-cut CWC TSS by MHPT were in a significant impact （0.05 level） in factors X1 （heat treatment temperature） , X3 （storage time） , X2*X2 （the square of heat treatment time） ,X3*X3 （the square of storage time） and X1*X3 （the cross-term of temperature and storage time）.（3）The model of pH wasY=-4．39873+0．34586*X1+0．04376*X2+0．13277*X3-0．002949*X1*X1+0．001551*X1*X2- 0．004323*X1*X3-0．002646*X2*X2-0．002153*X2*X3+0．007488*X3*X3Effects on fresh-cut CWC pH by MHPT were in a significant impact （0.05 level） in factors X1 （heat treatment temperature） , X1*X1 （the square of heat treatment temperature） and X2*X2 （the square of heat treatment time）. When the fresh-cut CWC treated under 59℃in 22 min, and storage for 3 days, the maximum predictive value of pH was 6.95.（4）The model of the ration of water loss （RWL） wasY=-5．4678+0．14147*X1+0．230417*X2+0．05776*X3-0．001247*X1X1-0．00136*X1*X2 +0．003244*X1*X3-0．003568*X2*X2-0．001611*X2X3-0．000192*X3*X3Effects on fresh-cut CWC RWL by MHPT were in a significant impact （0.05 level） in factors X1 （heat treatment temperature）, X3*X3 （the square of storage time） and X1 * X3 （the cross-term of temperature and storage time）. When the fresh-cut CWC treated under 58℃in 19 min, and storage for 3 days, the minimum predictive value of RWL was 0.81%.3. The experiment of anti-browning indicated that CWC fruit BI and PAL activity in control and heattreatment were increased during the storage. The BI, PAL activity, TP and flavonoid content of control fresh-cut CWC fruit were always higher than that of heat treatment.4. The main sense of fresh-cut CWC:（1） Color description language was white, yellow-green and brown; Texture description language was wetting, rough, fibrous and brittle; Flavor description language was fresh, com flavor, faint scent, alcohol flavor and taste moldy.（2） Quantitative descriptive analysis （QDA） showed that the heat treatment could effectively delay the discoloration of CWC slices, flavor and texture.（3） Principal component analysis （PCA） showed that there were three main components. The weight of the first principal component was 24.81%, and major features were milky white, yellow-green, brown and rough. The weight of the secend principal components was 22.33%, and major features were fresh, faint scent and mildew. The weight of the third principal components was 13.74%, and major feature was fibrous.
As economic and technological development, increasing people’s living standards, packaging cartons have more and more variety and style. The requirements of decoration, structure and quality are also increasing. Relying on the traditional manual design methods could not meet the needs of community and market, and is also unable to adapt to the pace of the times. How to combine the national standard to the carton packaging design is related to the carton production and the packed goods compete with other countries for world market. So it is particularly urgent and important.AutoCAD is one of wide used softwares in packaging industry, but it is not professional packaging design software. In order to more easily applied to packaging design, AutoCAD is often secondary developed. The AutoCAD software, VBA development environment, China’s Corrugated Box Standard and the status of China’s corrugated box were analyzed in this study. Features of the AutoCAD software used in corrugated packaging design were also summarized. Moreover, AutoCAD ActiveX technology was used for the secondary development of corrugated box design system.The content of design are as follows:1. The carton design features were studied and practice experience was used for reference, conversion formula between the corrugated box size was concluded: inner dimension; manufacturing size = inner dimension + the thickness of paper + constant; outer dimension= manufacturing size + thickness of the paper + Constant, “size optional module” and “correction coefficients module” were designed.2. In accordance with various box features in national standards, identifying common features on size, the key parameters to control carton shape could be selected. Three size parameters: length (L), width (W), high (H) were selected as the constrained parameters for parameters design to design “parameter input module”. And according to types of carton box in national standards, “cartons choice module” was designed. 3. Different corrugating paperboard has different thickness, which is very important to the dimension of carton design, so, according to this, I designed a “material option module”.4. In practical production, we always need to use engineering templet when protracting AutoCAD graphics, so I designed an “engineering templet module” to save the time that takes user to protract engineering templet, and improve efficiency.5. In AutoCAD visual development environment of VBA was started, the corresponding project documents were established, and various modules, form, control, definition of the object attributes were added, and the procedure codes corresponding to objects were written to complete the whole design project.Compared with other packaging design software, the advantage of my search is that:1. The data of this system is based on national standards of corrugating paperboard and corrugating carton, which impenetrated the whole course of design.2. Using is more simple and convenient, interface is more friendly.3. The system has openness to offer a further exploitation to user and base exploitation to professional designers.4. The system supplies demonstration courseware for section of Packaging Engineering in university, and new thought in packaging engineering application for students.This system data use China’s corrugated boxes national standards for reference, to achieve parameters ichnography drawing on corrugated packaging design, it greatly facilitate the mapping work, and play a role on promotion of the China’s corrugated box production standardization.
The paper studied on preparation of protein hydrolysate from fish waste of hairtail, deodrization and utilization of hydrolysate which will provide reasonable and scientific basis.The results showed as follows:1.The content of total protein from fish waste of hairtail was 16.44%,fat was 17.83%,moisture was 75.50%,ash was 13.85%.2.Single Enzyme hydrolytic experimentsIn the experiment,papain,pepsin, flavor enzyme, Neutral Proteinase, trypsin were used to hydrolyze fish waste of hairtail.The effect of temperature,time,enzyme amount,pH value and solid/liquid ratio on hydrolysis were studied through the method combining orthogonal.Through the analysis of experimental data,the optimal proteases were determined.They were papain and trypsin.3.Compound enzyme hydrolytic experimentsIn the experiment,The best compound enzyme were used to hydrolyze fish waste from hairtail, The effect of temperature, the amount of enzyme,pH value and time on hydrolysis were studied through the method combining orthogonal.Through the analysis of experimental data,the optimal condition were determined. The temperature 55℃,time 6h,the amount of enzyme 4%,pH value 7.5.It showed that the temperature and the amount of enzyme was remarkable factor in the test through the variance analysis.4.Acid hydrolysisThe experiment of acid hydrolysis was studied in order to compare the effect of hydrolysis method on hydrolysis impact.The effect of temperature ,the concentration of acid,time and acid amount on hydrolysis were studied through the method of orthogonal trials.Through the analysis of experimental data,the optimum condition of acid hydrolysis was determined,the temperature 95℃,the concentration of HCl 6mol/L,time 6h,HCl solution/substrate ratio 6:1.The degree of hydrolysis at this condition is very high. the condition of acid hydrolysis was rigor, But the nutrient content of product was nearly destroyed,and the colour of hydrolysate was chocolate brown. So the main purpose of this paper is to compare with enzymatic hydrolysis. 5.Degreasing treatmentIsopropanol,hexane,Ethyl Acetate were used as extractant to degrease and compare with these degreasing effect respectively. The optimum degreasing reagent was Ethyl Acetate.6.Deodorizing treatmentThis research was mainly to study on fishy smell of protein hydrolysate of fish waste from hairtail by sensory evaluation, respectively using theβ-cyclodextrin,Gelatin,Starch and Activated Carbon in order to dedorizethis smell,investigated the protein loss rate and fishy smell and the optimum was Activated Carbon,adopted single factor and orthogonal experiment method,the temperature 65℃,time 40min,the content of Activated Carbon was 0.3%. Under this condition,not only reduce the protein loss rate,but also make the hydrolysate became light.It showed that the Activated Carbon can make the colour of hydrolysate became clear and can be debitterized and decolored.The quanlity of protein hydrolysate was improved.7.The paper studied on the emulsifying property,foamability and foam stability from protein hydrolysate of fish waste from hairtail which will provide proper research basis.And the antioxidation capacity of hydrolysate used in grease system was preliminarily studied.It showed that compound enzyme of hydrolysate used in grease system exhibited antioxidative activity.8.The proportion of lactic acid bacteria Streptococcus thermophilus:Lactobacillus bulgaricus= 1:1,seeding amount 2%,sugar concentration 1%,fermented for 36h unnder 42℃,the flavor of the fermentation liquid was the best.The fishy smell were removed.
The paper mainly discussed the interaction of NaClO3 with H2SO4 under the condition of H2O2 as catalyst to produce chlorine dioxide gas and then identified its purity and concentration using five steps iodimetry and colorimetry.Also the stability of chlorine dioxide gas was studied.Through the fresh-keeping experiments of three representative samples using chlorine dioxide as a food preservative,the best preserve condition and the most suitable concentration of chlorine dioxide has been identified.And during the preserving time,we emphasized on the quality evaluation of the samples.The results are below:1.Preparation of ClO2:Under the condition of 1mL H2O2 as catalyst and maintained the reaction temperature at 95℃using water heating,20%NaClO3 interreaction with 30%H2SO4 can produce ClO2 whose purity can reach 96.9%.Theλmax at 360nm was identified thought spectrum scan from 200nm to 700nm and the Standard curve about concentration of ClO2 to ABS was settled at 360nm.2.The stability of ClO2:The most suitable pH for preservation of ClO2 is about 6,higher or lower can accelerate its decomposition and decrease its stability.With the increasing of the temperature,the rate of decomposition becomes faster and faster.Results showed us:The concentration of ClO2 was 70mg/L under the condition of 5℃and aviod light after 30 days’preservation compared to 12.8mg/L and 2.54mg/L which was under 15℃and 25℃respectively.Avioding light is good for the stability of ClO2.Under the condition of derectly sunshining for 4.5 h,ClO2 reduced 92.1%of its concentration compared to only 5.2%under avioding light condition.3.Preservation of chilled meat:ClO2 can effectively prolong the shelf life of chilled meat by reducing the original CFU and after dealing with ClO2,CFU of chilled meat decreased with the increase of the concentration of ClO2.The results showed us:Dealing with 50mg/L ClO2 1 min can low the CFU 1.2 lg.And the shelf life of chilled meat can be prolonged almost 6 days more and TVB-N sustained about 16.40mg/100g which is 31.76mg/100g less compared to the contrast’s 48.16mg/100g which was preserved under 3±1℃through dealing with 150mg/L ClO2 at the same time.Through POV and TBARS tests the results showed us:ClO2 had nothing to do with fat oxidation directly.However the unpleasure odor、color fade、unique flavor disappear causing by using higher concentration of ClO2 were seriously devalued the quality of cattle stomach.4.Preservation of cattle stomach:The optimal combination we got from preservation of cattle stomach was A1B3C1,the concentration of ClO2 was 250mg/L,immersion time was 1 min and preservation temperature is 1℃.And primary-secondary factor were:preservtion temperature＞concentration of ClO2＞time of immersion.5.Preservation of duck intestine:ClO2 can effectly reduce CFU and TVB-N during the preservation.CFU、TVB-N and pH were decreased with increase of ClO2,while shelf life prolonged with increase of ClO2 either.The results showed:Packed with pallet and freshing keeping film covering and stored under the temperature of 3±1℃,s,etting the contrast at the same time,the 9th day’s testing and compared to the contrast,CFU was decreased 13.74%、38.32%and 44.27% respectively,TVB-N was decreased 39.24%、69.48%and 75.12%respectively,pH was decreased 17.72%、17.72%and 20.25%respectively.ClO2 can promote the water losing at the start of the preservation.And at the same time the unpleasure flavor and color fade、water losing which bringed by dealing with ClO2 seriously devalued the sensory evaluation.
In this research,a novel chromatographic analysis method is established to analyze polycyclic aromatic hydrocarbons（PAHs）in smoking meat products by combining solid-phase extraction technology（SPE）with high performance liquid chromatography（HPLC）,aiming to overcome the defects in general method detecting PAHs in smoking meat products analysis such as:solvent toxicity,bio-hazard.this method is proved to meet the basic demand of PAHs analysis and possesses high recovery rate,less-time cost,good repeatability and feasibility.By using SPE to pre-treat for smoking meat products,then using diode array detecter（PDA）to detect the PAHs in the sample,the result showed that this method is feasible,exact and precise.The conclusions in this paper were mainly as follow:（1）In this thesis,used commercial SPE column,filling with C18,Florisil,alkali aluminum oxide and silica gel,by comparing the recovery rate of the four absorbent,the recovery rate of C18is 80.7%～100.5%,the other three absorbent is 24.2～58.4%,20.5～52.5%,10.6～39.4%respectively. The total absorbent rate of C18to sixteen PAHs is 98.2%.and the tatal absorbent rate of other three SPE columns to sixteen PAHs is 54.7%、48.9%、37.2%respectively.The coefficienr of variation of the four SPE columns is 1.17%～3.07%、0.63%～3.02%、1.09%～3.12%respectively.So,C18 column have more rxtraction effect for PAHs in smoking meat products.（2）When using C18pole to pre-treat the PAHs,the eluting effects among dichloromethane, methanol,acetonitrile and tetrahydrofuran have been compared.The recycle rate is 85.0%～98.7%、15.9%～87.9%、56.0%～77.3%、11.0%～39.3%respectively.So the dichloromethane have most eluting effect for PAHs in C18,and the eluting effect of tetrahydrofuran is the poorest.The volume of elute is 10 ml.（3）The operating condition of chromatogram has been optimized.The chromatogram pole is Hypersil BDS 250mm×4.6mm×5um C18reversed phase High-efficiency Liquid Chromatography column.The mobile phase is acetonitrile and water,The detector is PDA;the quantificational wavelength is 254 nm,;the velocity of flow is 1.0mL/min;the volume of injection sample is 20μl; the temperature of pillar is 30℃.when the range concention is 0.01～2μg/mL,the correlation coefficient is 0.9962～0.9997,The all relative standard deviation is less than 1%.（5）The feasibility of SPE-HPLC method are validated by standard appending 60ng/mL, 100ng/mL,and 1μg/mL respectively in smoking meat products,in this way,when the concentration is 60ng/mL,the recovery rate is between 69.5%and 95.4%,correlation coefficient is between 2.1% and 4.1%;when the concentration is 100ng/mL,the recovery is between 70.8%and 97.4%, correlation coefficient is 1.4%to 4.8%;and when the concentration is 1μg/mL,the recovery is 77.2% to 102.5%,correlation coefficient is 1.6%to 4.0%,Based on those experiment results,showed that the exact,precise and sensitive of the method of soxhlet extraction,cyclohexane extraction and SPE-HPLC can meet the PAHs in smoking meat products analytical demand.（6）The analysis of the PAHs in smoking meat products:Using the method of SPE-HPLC to detect the PAHs in smoking pig’s meat products,the results showed that 15 kinds of PAHs have been detected in the sample from GUIZHOU,the kinds of PAHs was less in the sample from CHONGQING,many mixed apex have been detected in the sample from SICHUAN and HUNAN,which would absorbed other substance in fumigate process.In the 16 samples,the content of naphthalene was high,account for 29.46%of the total contention of its,fluorene and phenanthrene accounted for 11.67%and 11.16%respectively.Considering the structure of the PAHs, the three-ring PAHs accounted for 44.7%of the total PAHs,and the two-ring PAHs was second which accounted for 27.7%.The analysis to five carcinogenic PAHs,showed that the average content of benzo[g,h,i]anthracene was the highest,which is 0.99125μg/kg,dibenz[a,h]anthracene was second,which is 0.895625μg/kg,benzo[a]pyrene was lowest,which is O.019375μg/kg,all lower the regulated the most content 5μg/kg by china,and lower contention of benzo[a]pyrene 1μg/kg which is regulated lowest standard in meat products by foreign countries.Using the method of SPE-HPLC to detect the PAHs in smoking banger’s meat products also, which came from four different area in CHONGQING.In smoking banger meat products,fourteen kinds of PAHs have detected.In the four samples,the content of naphthalene was high,account for 28.9%,benza[a]anthracene and benza[b]fluoranthene can detected in three samples,and their average content is 1.065μg/kg and 0.22μg/kg respectively.Only one smoking banger meat products contained benzo[a]pyrene,its content is 0.024μg/kg,all lower the regulated the most content 5μg/ kg by china.