| In the present study, two application patterns ofβ-cyclodextrin (β-CD) in antimicrobial food packaging were investigated using the volatile antimicrobial cinnamaldehyde (CIN).One is to prepare the antimicrobial inclusion complex withβ-CD and then incorporate the inclusion complex directly into polymers material. The other way is to covalent immobilization ofβ-CD onto polymers to obtain the antimicrobial functional material by the complexation of the fixedβ-CD with antimicrobial agents. Finally these two functional packaging materials were used in chiffon cake to anti-mildew .Cinnamaldehyde (CIN) has strong activity in inhibiting molds and food spoilage bacterium. In the present study, packaging systems that release volatile antimicrobials was simulated by entrapping CIN withβ-CD or fixedβ-CD in fabrics. At first the controlled-releasing inclusion complex was prepared by cinnamaldehyde andβ-cyclodextrin as raw material through sealed-thermal control method .The parameters and controlled-release properties of inclusion complex were also obtained. The results showed that the optimum conditions for inclusion were established by one factor and response surface methodolody as follows: The inclusion time and temperature were for 2.5h and at 100℃, oil:β-cyclodextrin was 1:1.75.At the same, the inclusion complex was validated by IR. And through molecular modeling software packages chemoffice2008 identified the inclusion form. Release rate of cinnamaldehyde from theβ-CD-CIN complex is correlated with environmential relative humidity (RH),not with the temperature.Specific migration studies were performed for CIN using polylactic acid membrane matrix filled with food stimulant. The result showed that the migration behaviors were influenced by the type of food stimulant .In the low-alcohol food system, the CIN didn't migrate in polylactic acid membrane, but did in high-alcohol solution .when inclusion complexes of antimicrobials were added into the membrane ,the migration had been much improved due to their impact on the membrane structure properties , and more the migration rate was also affected by the control release mechanism of cyclodextrin. In 50% ethanol solution or 60% glycerol system CIN moved faster from membrane , while in 10% ethanol solution the release become slow obviously and release level is very low in hexane .It could be concluded that the antimicrobial membrane withβ-CD complexes had longer-lasting effect in high-water-activity foods.β-cyclodextrin(β-CD) was grafted onto cellulose fibers used citric acid (CA) as crosslinking agent ,the process parameters were studied. The antimicrobial cinnamaldehyde was complexed with fiber-reactiveβ-CD ,the release properties of the obtained inclusion complex were investigated, it was observed thatβ-CD could be grafted onto fibers by CA method , graft technical parameters, heating time is 5～7 min; heating Temperature is 160～ 180℃; molar ratio (CIN :β-CD) is 5:1～7:1 when the grafting yield ofβ-CD was between 12% and 14%,the inclusion rate of cinnamaldehyde was about 8～9μL/g .Release rate of cinnamaldehyde from the functional fiber was increased as environmential relative humidity (RH) increased.Finally, the cinnamaldehyde polylactic acid membrane and cinnamaldehyde functional fibers were used in the chiffon cake packaging system, the test proved that they own a good anti-mildew effectiveness, which can effectively improve their security and to extend shelf life.
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