研究聚乙烯(PE)、聚乳酸(PLA)、聚氯乙烯(PVC)、偏氯乙烯–氯乙烯共聚物(VDC/VC)四种材质的保鲜膜对采后生菜常温贮藏期间品质的影响。以无膜包装作为对照，通过定期测量不同保鲜处理下的生菜失重率、可溶性固形物含量、维生素C含量、叶绿素a含量、叶绿素b含量和总叶绿素含量的变化趋势对比出不同保鲜膜对生菜贮藏品质的影响。实验发现VDC/VC材质的保鲜膜能更有效地抑制采后生菜的水分流失及变质腐烂速度，该处理下的生菜在d 6时的感官评分为7分，失重率为2.47%，均优于无膜对照组；PVC及VDC/VC材质保鲜膜能更有效地维持采后生菜叶绿素的含量变化，在第6 d时，PVC处理下的生菜叶绿素a、b及总叶绿素含量分别为0.045 mg/g、0.016 mg/g、0.061 mg/g均高于其余4种不同保鲜处理下的生菜叶绿素含量；PLA材质的保鲜膜能更好地将VC含量保持在较高水平，其中在6 d时，该处理下的生菜VC含量有2.80 mg/g均大于其余3组不同包装材料的实验组；PLA保鲜膜能更有效地稳定生菜可溶性固形物含量的变化，在第4~6 d时，PLA包装组变化幅度均为0.5%小于其余实验组。结果表明有保鲜膜包装比无保鲜膜包装更能延长采后生菜的货架期及商品价值。
The effects of polyethylene
(PE), polylactic acid (PLA), polyvinyl chloride (PVC) and vinylidene chloride-vinyl/chloride
copolymer (VDC/VC) on the quality of postharvest lettuce during room temperature storage were
studied. With no-film packaging as the control, the effects of different
preservative films on the storage quality of lettuce were compared by
periodically measuring the variation trends of weight loss rate, soluble solid
content, vitamin C content, chlorophyll a content, chlorophyll b content and
total chlorophyll content of lettuce under different preservation treatments.
It was found that the VDC/VC fresh-keeping film could more effectively inhibit
the water loss and decay rate of postharvest lettuce. The sensory score of
lettuce under this treatment at d 6 was 7 points, and the weight loss
rate was 2.47 %, which were better than those of the control group without film. PVC and
VDC/VC fresh-keeping films could more effectively maintain the changes in
chlorophyll content of postharvest lettuce. On the sixth day, the chlorophyll
a, b and total chlorophyll contents of lettuce treated with PVC were 0.045
mg/g, 0.016 mg/g and 0.061 mg/g, respectively, which were higher than those of
lettuce treated with four different fresh-keeping treatments. The fresh-keeping
film made of PLA could better maintain the VC content at a high level, and at d
6, the VC content of lettuce under this treatment was 2.80 mg/g, which was
higher than that of the three groups of different packaging materials. PLA
fresh-keeping film could more effectively stabilize the change of soluble solid
content in lettuce. On the 4th-6th days, the change range of PLA packaging
group was 0.5% less than that of the experimental group. The results showed
that the shelf life and commodity value of postharvest lettuce with
preservative film packaging were longer than those
Munesue, Y., Masui, T. and Fushima, T. (2015) The Effects of Reducing Food Losses and Food Waste on Global Food Insecurity, Natural Resources, and Greenhouse Gas Emissions. Environmental Economics & Policy Studies, 17, 43-77.
https://doi.org/10.1007/s10018-014-0083-0
Avinc, O. and Khoddami, A. (2010) Overview of Poly(Lactic Acid) (PLA) Fiber: Part II: Wet Processing; Pretreatment, Dyeing, Clearing, Finishing, and Washing Properties of Poly(Lactic Acid) Fibres. Fibre Chemistry, 42, 68-78.
https://doi.org/10.1007/s10692-010-9226-7
