聚乳酸/茶多酚复合包装膜的制备及性能  

Preparation and Properties of Polylactic Acid/Tea Polyphenol Composite Packaging Film

作　　者：陈婕 梅林玉[1] CHEN Jie;MEI Lin-yu(School of Mechanical Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学机械工程学院,太原030051

出　　处：《包装工程》2021年第23期100-108,共9页Packaging Engineering

基　　金：山西省研究生教育创新项目(2020SY346);中北大学自然科学研究基金(XJJ201924)。

摘　　要：目的对比不同制备方法对复合包装膜性能的影响,以获取具有优良保鲜性能的食品包装膜及其制备方法。方法以可降解生物材料聚乳酸(PLA)为基材,掺杂茶多酚(TP)活性物质,分别采用静电纺丝法和流延法制备不同质量比的PLA/TP复合包装膜,通过扫描电镜、接触角测试、溶胀性测试、水蒸气透过性测试及抗氧化性测试分析薄膜的形貌和理化性能,并对2种方法制备的复合膜的TP释放行为和草莓保鲜性能进行对比分析。结果流延膜呈致密多孔结构,纺丝膜呈多层纳米纤维叠加结构;2种复合膜的接触角均随TP质量分数的增加而减小,当TP质量分数从0%增加至20%时,流延膜的接触角从62.70°±3.09°减小至44.08°±2.24°,呈亲水性,纺丝膜的接触角从124.39°±1.69°减小至112.90°±2.42°,呈疏水性,且流延膜的水蒸气透过量随TP质量分数增加而增大,当TP质量分数为20%时,水蒸气透过量增大至(396.93±16.36)g/(m^(2)·d);纺丝膜的溶胀性远高于流延膜,当TP质量分数为20%时,纺丝膜的溶胀率高达347.63°±5.36°,流延膜的溶胀率仅为13.36°±0.56°;随着TP质量分数增加,流延膜和纺丝膜的1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除率均逐渐提高,最高分别达(89.76±1.4)%和(97.26±1.25)%;2种膜中TP的释放行为均符合先快后慢的规律,且随着TP质量分数增加而增大,不同流延膜在720h后累积释放百分比范围为50%~85%,纺丝膜在240h后基本释放完全,累积释放百分比为75%~95%;流延膜比纺丝膜对草莓的保鲜效果更优,分别将草莓的货架寿命延长至18 d和9 d。结论流延法制备的复合膜具有亲水性、高水蒸气透过性、高抗氧化性能和优异缓释性能,能有效延长草莓的货架寿命至18 d;纺丝膜制备的复合膜具有疏水性、高溶胀率、优异抗氧化性能,但释放速率快,能有效延长草莓的货架寿命至9 d。The work aims to compare the effects of different preparation methods on the properties of composite packaging film so as to obtain food packaging film with excellent fresh-keeping performance and its preparation method.PLA/TP composite packaging films with different mass ratios were prepared by electrospinning and tape casting,with biodegradable material polylactic acid(PLA)as substrate and tea polyphenol(TP)as active material.The morphology and physical and chemical properties of the films were analyzed by SEM,contact angle test,swelling test,water vapor permeability test and oxidation resistance test.The TP release behavior and the fresh-keeping properties of strawberry of the composite films prepared through the aforementioned two methods were compared and analyzed.The casting film had a dense porous structure and the electrospinning film had a multi-nano-fiber superimposed structure.The contact angle of the two composite films decreased with the increase of TP mass fraction.When the TP mass fraction increased from 0 to 20%,the contact angle of casting film decreased from 62.70°±3.09°to 44.08°±2.24°,which was hydrophilic.The contact angle of electrospinning film decreased from 124.39°±1.69°to 112.90°±2.42°,which was hydrophobic.The water vapor transmittance increased with the increase of TP mass fraction.When the TP mass fraction was 20%,the water vapor transmittance increased to(396.93±16.36)g/(m^(2)·d);The swelling rate of electrospinning film was far higher than that of casting film.When the TP mass fraction was 20%,the swelling rate of electrospinning film was 347.63°±5.36°,and the swelling rate of casting film was only 13.36°±0.56°.With the increase of TP mass fraction,the 1,1-diphenyl-2-trinitrophenylhydrazyl(DPPH)radical scavenging rate of casting film and electrospinning filmgraduallyincreased up to(89.76±1.4)%and(97.26±1.25)%respectively.The release kinetics of TP in the two films were first fast and then slow,and increased with the increase of TP mass fraction.The accumulative

关 键 词：茶多酚 聚乳酸 静电纺丝 流延法 保鲜性能 

分 类 号：TS206.4[轻工技术与工程—食品科学]