Abstract:Cyclodextrins(CDs) are mainly prepared from starch by the catalyzation of cyclodextrin glucosyltransferase(CGTase).In addition to the source of CGTase,many factors influence the ratio and specificity of CDs,such as reaction time,reaction temperature,pH,enzyme quantity,additive,type of substrate,substrate concentration,pretreatment of raw material et al.The CDs preparation processes are also effected by these factors.However,no system reports focused on the influence factors for CDs preparation.In this paper,we described the catalytic mechanisms of CDs preparation,and a review on the influence factors in CDs preparation process was presented,in order to provide reference for CDs preparation.

Abstract:In this paper,the process of enzymatic catalysis for the synthesis of dextrin ester was investigated.The single factor and the orthogonal experiments for the affecting factors of this technology were carried out.Under the optimum conditions of 7 g/L lipase from Novozym 435,and acid/dextrin molar ratio of 4∶1 at 65 ℃ for 60 h,the optimum process was achieved.The results showed that:the emulsification increased with the concentration of dextrin esters.At the same concentration,the emulsification of the dextrin ester is higher than that of maltose ester and starch ester.

Abstract:Benzoylformate decarboxylase gene(mdlC) from Pseudomonas putida ATCC12633 was inverted into Escherichia coli(E.coli) strain BL21(DE3) and was efficiently expressed after induction with IPTG.The recombinant strain together with E.coli/pET30a-mdlB converted successfully(S)-4-hydroxy-3-ethoxymandelic acid(EMA) to ethyl vanillin in the forms of mixed resting cells.Without optimization,all the(S)-EMA was consumed to form ethyl vanillin(1.94 g/L) and no by product was obtained with the initial substrate concentration 5 g/L by after 24 h.The cells could maintain their enzyme activity in repeated utilization at least three times and shortened bioconversion time efficiently.

Abstract:Due to its abundant conjugated double bonds in the molecule,lycopene is highly unsaturated and tend to configuration-changing and/or oxidative degradation during its procession and storage.In this paper,we studied the configuration-changing and total amount changes of lycopene in the process of microemulsion preparation and storage via Cosmosil Cholester-HPLC system.The results indicated that all-trans lycopene would be transferred into 4 different cis-isomers besides all-trans itself in the process of microemulsion preparation,the ratio of all-trans lycopene,9-cis lycopene,13-cis lycopene,x1-cis lycopene and x2-cis lycopene were 43.99%,17.96% 15.65%,7.85%and 9.64%respectively in lycopene microemulsion,while 9-cis lycopene was more stable than 13-cis lycopene during the storage.After storing at 4 ℃ for 40 days,93.4% of trans-lycopene and 80% of total cis-lycopene were retained,however,at 37 ℃ for 40 days,76.4% of trans-lycopene and 21.2% of total cis-lycopene were retained respectively.

Abstract:Effect of treatment with 0.4μL/L,0.8μL/L or 1.2μL/L 1-pentylcyclopropene(1-PentCP),compared with that of treatment with the same concentrations of 1-MCP,on postharvest physiology and storage quality of green mature ’Fentailang’ tomato fruits(Solanum lycopersicum L.) at room temperature(18±2℃) were investigated.The results show that all the 1-PentCP and 1-MCP treatments slowed down the decline of fruit hardness,delayed the occurrence time of super oxygen dehydrogenises(SOD) activity peak,reduced the loss of vitamin C,inhibited the decrease of tannin content and the ascent of soluble sugar content,reduced the accumulation of methane dicarboxylic aldehyde(MDA) and delayed the appearance of its peak.The effect of delaying ripening and senescence of tomato fruits treated with 0.8μL/L 1-MCP or 0.4μL/L 1-PentCP was obviously superior to other concentrations,but treatment with 0.8μL/L 1-MCP was better than that with 0.4μL/L 1-PentCP.

Abstract:A sensory panel was trained to screen a list of texture attributes to evaluate different dried bean curds by Spectrum descriptive sensory analysis method.Panel performance during training sessions including panel agreement,panelists’ discrimination ability and repeatability was studied by the development of signal to noise ratio and Panel Check software.Furthermore,principal component analysis presented a general overview over how the attributes were structured among the dried bean curds.The results showed that the trained panel performed well and the data was reliable.The major texture attributes of dried bean curds were surface oiliness,cohesiveness,hardness,cohesiveness of mass and number of chewing.

Abstract:The orthogonal experiment was used in this paper to study the influence of different cold wind drying conditions on the sensory quality of smoked chicken.The results showed the optimum cold wind drying conditions were temperature:16 ℃,relative humidity:65%,wind speed:4 m/s,time:72 h.Finally,the characteristics of product’s quality were valued by Texture analyzer,and the results were,hardness:(2 235.813±17.841) g,chewiness:(1 366.467±29.543) g.s,cohesiveness:(0.717±0.004)%,springiness:(0.852±0.016)%;then the color of products with different temperature of cold wind drying were valued by Chroma meter,and the results were as the temperature rised,L* value rised,a* value declined,b* value rised;and also Volatile flavor compounds of product were extracted with solid phase micro-extraction(SPME) apparatus and analyzed and identified by GC-MS.

Abstract:Semi-dried noodle is a new type of instant food,and has a good development prospect.Drying is one of the most important processes in the production of semi-dried noodle,and has a great impact on its quality and preservation.In this work,ultraviolet-microwave drying and electric drying were used to dry the fresh noodle and to comparatively investigate their effects on the preservation and quality of semi-dried noodle.The experimental results show that the efficiency of electric drying is lower than that of ultraviolet-microwave drying,in the later stage of drying,the sterilizing effect of electric drying is not obvious while the number of bacteria of noodle dried by ultraviolet-microwave drying continue to decline.Both of the drying means can make the initial number of bacteria of semi-dried noodle reduce obviously.For electric drying,125 ℃ is the suitable drying temperature.At this temperature,the number of bacteria decreased significantly,but the texture and cooking quality of semi-dried noodle is not notably deteriorated.For noodle dried by ultraviolet-microwave,its number of bacteria is distinctly lower than that of electric drying.When microwave power is set at 2 000 W,semi-dried noodle can keep relatively high quality,hence 2 000 W is the suitable drying power.

Abstract:The deep processing of Chicken bone which is rich in nutrients can improve comprehensive utilization of protein.In this article,chicken bone was hydrolyzed by Flavourzy meand Protamex which ratio is 2∶1,which is determined by the comparison different hydrolysates.Theresult showed that optimal conditions for hydrolysiswere:temperature 55 ℃,pH 6.5,and 5 hours,enzyme dosage 0.8%,solid-liquid ratio1∶2.Under these optimal hydrolysis conditions the hydrolysis degreewas 23.69%.The protein hydrolysates will be used for the analysis of the effect of different hydrolysis degree on the Maillard reaction.

Abstract:The conditions of extraction and separation and the dissolution characteristics on the pigment of fusarium are studied.The results of Experimental show that the best extraction solvent of the pigment is pure acetic.The pigment only can dissolve in organic acids and acidic organic solvents.The best high-performance liquid separation conditions of the pigment are the followings:the column is Phecda C18(4.6 mm×250 mm,5 μm).The temperature of the column is 25 ℃.The detection wavelength of the DAD detector is 254 nm.The flow rate is 1.0 mL/min.The injection volume is 1μL.The mobile phase A is acetonitrile containing one-thousandth of trifluoroacetic acid.The mobile phase B is distilled water containing one-thousandth of trifluoroacetic acid.The gradient elution program is that:mobile phase A,0~3 min,2%~6%;3~3.1 min,6%~45%;3.1~28 min,45%~70%;28~32 min,70%~80%.Eight kinds of pigments are obtained,and four kinds of pigments are red,three orange,one yellow in acidic acetonitrile.In accordance with the order of the peaks,their maximum absorption peaks are 508、458、456、498、510、456、454、506 nm respectively.

Abstract:With ultrafine grinding process,an ultrafine powder of Garnoderma lucidum powder was obtained.Charactering and detecting results of the ultrafine powder,general powder(60 mesh) and superfine powder of Ganoderma showed that the particle diameter size distribution of the ultrafine powder was is 2.92~6.03 μm,the 50% particle diameter(D50) and the 100% particle diameter(D100) of the ultrafine powder were 3.18 μm and less than 9.96 μm,and showed unimodal distribution and well uniformity.The specific surface area of ultrafine powder with 3.63 μm/g is 15 times and 2 times of the general powder and superfine powder,respectively.Meanwhile,all cell walls of the ultrafine powder was completely broken.The leaching rate in water of polysaccharide,the main functional component within 20 minutes reached the level of the superfine powder at 2 hours which suggested that the bioavailability of the ultrafine powder of Garnoderma powder was effectively increased.The results will provide a new knowledge for developing new products with Garnoderma powder.

Abstract:The raw materials and microbial changes in different periods of production process of canned marine products were investigated,using Skipjack Tuna production as an example in this paper.The effects of processing factors on the total bacterial population and histamine content were also studied.The crucial control points of entire production process were established including the raw material examination,defrozen cleaning,precooking,ingredients and can sealing.A HACCP plan was established,meanwhile the monitoring program and rectification measures were set up.The total bacterial population and histamine content of tuna in the canning processing were compared by adopting the HACCP plan established.The results showed that the bacterial population reduced about 30% in the phase of defrost by HACCP procedure.It also reduced by 49% for the final product.The histamine content of the final product is also reduced from the 3.5 mg/kg to 1.5 mg/kg.These results demonstrated that the hygiene quality and preservation period of the Skipjack Tuna product have been improved.

Abstract:The investigation was conducted to determine the efficacy of DSC as a browning inhibition agent of fresh-cut and canned Agaricus bisporus.DSC and other anti-browning agents as well as the new compound color fixative ware used in pretreatment and canned Agaricus bisporus.Residual activity of PPO and the browning degree(BD) were measured as performance figures.DSC played an important part in enzymatic browning inhibition,compared to other anti-browning agents such as phytic acid,citric acid and VC.The sliced Agaricus bisporuss pretreated with mixed liquor containing 0.2% citric acid,0.03% DSC,0.02% phytic acid,0.03% VC were effectively kept from enzymatic browning and then blanched.In addition,the products with DSC resulted in better performance than those with sodium metabisulphite as well as other anti-browning agents.The best compound color fixative of anti-browning agents in the cans was to be 0.03% DSC,phytic acid 0.02%,citric acid 0.1% and 0.3% CaCl2,which leaded to a similar effect of browning inhibition,as compared with 0.02% of sodium metabisulphite.In general,DSC proves to be able to take the place of sodium metabisulphite and act as a new safe and effective anti-browning agent used in canned Agaricus bisporuss.

Abstract:The influencing factors in the enzyme solution process of Rana skin collagen peptide(LWT) were optimized by using the mathematical statistics and data fitting analysis method.And the relationship between the influencing factors and hydrolyzing degree in the enzyme solution process of LWT was established.And the best value hydrolysis degree(peak) was forecasted.Used polyacrylamide gel electrophoresis method to determine the molecular weight of LWT which was under 3 500.High performance liquid chromatogram showed that the purity was in the high level.In the antioxidant effect of LWT on liver damage of bromobenzene mice were studied.The results showed that LWT have the remarkable effect on reducing MDA content and the obvious effect on rising SOD vitality in mice liver tissue and have antioxidant effect.

Abstract:Based on the index of crude protein content,the optimum medium of protein feed of milk thistle meal by solid-state fermentation was determined by using single factor experiment and the Box-Behnken response surface analysis.The optimized compositions of medium were as follows(w/w):mass ratio of milk thistle meal,wheat bran and corn flour in the basic materials was 8∶1.5∶0.5;glucose,urea and phosphate monobasic potassium were accounted for 1.11%,1.40% and 0.56%,respectively.Under these conditions,crude protein content of fermented sample was reached 38.43%.In vitro digestibility of the fermented product was measured under the optimum conditions.The result showed that in vitro digestibility of crude protein of fermented product was 88.92%,which was decreased by 18.80% compared to that of unfermented milk thistle meal(70.12%).from the 3.47 mg/kg to 1.45 mg/kg.These results demonstrated that the hygiene quality and preservation period of the Skipjack Tuna product have been improved.

Abstract:Maltotetraose is a key sugar in maltooligosaccharide family.It has quite some unique physical and chemical properties,such as low sweetness,low osmotic pressure,high viscosity,acid resistant and so on,which results in its wide application in food industry.Maltotetraose-forming amylases have been reported before,but few of them could be industrialized.The less thermostability and acid stability of the enzyme properties,and the cost of the enzyme make commercial production of the sugar less viable.A new acid stable and thermostable maltotetrasoe-forming amylase is introduced in this paper,and its operational process is optimized.The results showed that this new amylase could be operated at pH4.0~8.0,temperature from 55~70 ℃.At the same time,more than 50% maltotetraose syrup could be obtained with the presence of pullulanase.The new enzyme makes the production of maltotetraose more competitive.

Abstract:The effects of tempering temperature were evaluated on the physical behavior of palm oil-based margarine during various storage conditions.The physical properties were characterized based on hardness,rheological property,instant solid fat content,microstructure,thermal stability and polymorphic forms.The samples tempered at 20 ℃ had poor spreadability and post-hardening occurred during storage.Though the spreadability of the samples was best at 30 ℃;however,the samples were ingeneral too soft with also poor thermal stability;while sandiness happened and the β form crystal became the mass crystallization forms after three weeks storage under temperature cycles.When the tempering temperature was 25 ℃,the samples had a proper solid fat content profile,hardness,and spreadability,with also a stable crystallization network,mean while the stability is better and the crystals mostly present as β’ form under temperature cycles during storage.The study also indicates that the stable tempering temperature is critical.Slight temperature variation such as up to 5 ℃ can lead serious difference of the product properties.