Department of Industrial Engineering, University of Catania, Catania, Italy.
J Food Sci. 2012 Oct;77(10):E264-72. doi: 10.1111/j.1750-3841.2012.02905.x. Epub 2012 Sep 4.
This work reports an experimental study on the permeability and thermal behavior of commercial polypropylene (PP) film used for fresh-cut potatoes packaging. The permeability was tested using oxygen, carbon dioxide, nitrogen, mix of these 3 gases, normally used for modified atmosphere packaging (MAP) and Air, to understand if it would be possible to extend the shelf life of this food product designed for the catering field in respect to the packaging behavior. The temperature influence on permeability data, from 5 to 40 °C, was analyzed, before and after 4, 8, 12, 15, and 20 d of food contact, pointing out the dependence between temperature and gas transmission rate (GTR), solubility (S), diffusion coefficient (D), and time lag (t(L)) parameters. The activation energies (E) of the permeation process were determined with the different gases used in the experiments. The thermal behavior of PP film was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) to well understand its thermal stability. Fourier transformed-infrared with attenuated total reflectance (FT-IR/ATR) spectroscopy was also performed in order to study the influence of the food contact on the chemical characteristics of the polymer film. The results obtained were discussed and compared each other. Studied samples showed, for all investigated gases, an increase of gas permeability and S values at higher temperature. Heat resistance classification among the sample as it is and stored in modified atmospheres was made. Finally all performed experiments have showed good polymer stability for the shelf-life storage potatoes under study.
Study of packaging material was performed in a range of temperature, which can simulate the service condition to assess the suitability of a commercial polymer film for modified atmosphere packaging of fresh-cut potatoes minimally processed designed for catering purpose.
本工作报道了一项关于商业聚丙烯（PP）薄膜用于鲜切土豆包装的渗透性和热行为的实验研究。使用氧气、二氧化碳、氮气、这 3 种气体的混合物以及空气对渗透性进行了测试，以了解是否有可能延长为餐饮领域设计的这种食品的保质期，同时考虑到包装行为。分析了从 5 到 40°C 的温度对渗透性数据的影响，在食品接触前和接触后 4、8、12、15 和 20 天进行了分析，指出了温度与气体传输率（GTR）、溶解度（S）、扩散系数（D）和滞后时间（t（L））参数之间的关系。用实验中使用的不同气体确定了渗透过程的活化能（E）。通过差示扫描量热法（DSC）和热重分析（TG）研究了 PP 薄膜的热行为，以充分了解其热稳定性。还进行了傅里叶变换衰减全反射（FT-IR/ATR）光谱法，以研究食品接触对聚合物膜化学特性的影响。对得到的结果进行了讨论和比较。对于所有研究的气体，在较高温度下，研究样品显示出气体渗透性和 S 值的增加。对原样和储存于改性气氛中的样品进行了耐热性分类。最后，所有进行的实验均表明，在所研究的保质期储存土豆中，该聚合物具有良好的稳定性。
在温度范围内对包装材料进行了研究，该温度范围可模拟使用条件，以评估商业聚合物薄膜是否适合用于最小化加工的鲜切土豆的改性气氛包装，目的是为餐饮。
