[关键词]
[摘要]
该研究以聚对苯二甲酸己二酸丁二醇酯(PBAT)和聚丁二酸丁二醇酯(PBS)对聚乙烯(PE)进行共混改性,通过改善其气体透过性和防雾性,使其适用于草莓的自发气调保鲜包装,为草莓的贮藏以及运输提供更加优质的方法。该研究采用双螺杆挤出流延线制备PE/PBAT/PBS共混薄膜,同时与市售PE膜作对比保鲜草莓并测定其理化指标并分析。通过测定贮藏期间包装内的气体浓度、感官评定、草莓的失重率、可溶性固形物、总酚和黄酮含量等指标,评估PE/PBAT/PBS共混薄膜对草莓的自发气调保鲜效果。结果表明当PE/PBAT/PBS共混薄膜用于草莓包装时,薄膜内的CO2体积分数和O2体积分数从第3 天维持在CO2 5%~7%和O2 3%~5%的范围中,在此条件下,果实在23 d内维持了较好的感官品质,失重率保持在质量分数的5%以下,Vc含量在第23天达到44.72 mg/100 g,硬度下降到2.83 kg/cm2,可溶性糖的质量分数下降到8.47%,色差值维持在10左右,保持了果实中较高的黄酮和总酚含量,证明了PE/PBAT/PBS共混膜可抑制草莓的呼吸作用,为PE/PBAT/PBS共混薄膜可延长草莓保鲜期提供了理论支持。
[Key word]
[Abstract]
For better storage and transportation of strawberries, polyethylene (PE) was modified with poly(butylene adipate-co-terephthalate) (PBAT) and poly(butylene succinate) (PBS) to produce a novel PE/PBAT/PBS blend film with improved gas permeability and antifogging ability suitable for modified atmosphere packaging of strawberries. The PE/PBAT/PBS blend film was prepared by a twin-screw extrusion line and compared with a commercial PE film by analyzing the physical and chemical indexes of strawberries preserved in bags made of both films. The effect of applying the PE/PBAT/PBS blend film for spontaneous modified atmosphere packaging on strawberry preservation was evaluated by measuring the gas concentrations, sensory scores, weight loss rate, soluble solids content, and total phenolic and flavonoid contents of strawberries. At the third day of storage, the CO2 and O2 concentrations in the PE/PBAT/PBS packaging bags were consistent between 5%~7% and 3%~5%, respectively. Under these conditions, the favorable sensory quality of strawberries was maintained for 23 days, with a weight loss below a mass fraction of 5%; on day 23 of storage, the vitamin C content, firmness, and total soluble sugar of the strawberries only decreased to 44.72 mg/100 g, 2.83 kg/cm2, and 8.47%, respectively, with a color difference of approximately ten and consistently high flavonoid and total phenolic contents. These findings demonstrate that the PE/PBAT/PBS blend film suppresses the respiration of strawberries, providing theoretical support for its ability to extend strawberry shelf life.
[中图分类号]
[基金项目]
内蒙古农业大学高层次人才引进科研启动项目(DC1900007017)