Miller Katharina, Reichert Corina L, Schmid Markus, Loeffler Myriam
Meat Technology & Science of Protein-Rich Foods (MTSP), Department of Microbial and Molecular Systems, Leuven Food Science and Nutrition Research Centre, KU Leuven Campus Ghent, B-9000 Ghent, Belgium.
Sustainable Packaging Institute (SPI), Faculty of Life Sciences, Albstadt-Sigmaringen University, 72488 Sigmaringen, Germany.
Polymers (Basel). 2024 Dec 17;16(24):3506. doi: 10.3390/polym16243506.
The valorization of potato peel side streams for food packaging applications, especially for the substitution of current petrochemical-based oxygen barrier solutions such as EVOH, is becoming increasingly important. Therefore, potato peel-based films and coatings (on PLA) were developed containing 10-50% (/ potato peel) citric acid (CA). To determine the impact of CA concentration on the structure and physicochemical properties of cast films and coatings, ATR-FTIR spectroscopy, moisture adsorption isotherms, tensile properties, light transmittance, oxygen permeability, carbon dioxide transmission rate, and water vapor transmission rate measurements were performed. The results indicate that an increase in CA concentration from 10% to 30% increased esterification/cross-linking and resulted in minimal values for the oxygen permeability (0.08 cm m d bar) at 50% RH and water vapor transmission rate (1.6 g m d) at 50% → 0% RH, whereas an increase from 30% to 50% increased free CA concentration and resulted in increased flexibility, indicating that CA functioned as a plasticizer within the film/coating at higher concentrations. Overall, potato peel-based coatings containing CA showed comparable barrier properties to EVOH. We assume that an extensive industrial purification or fractionation of potato peel, which was not carried out in this study, could lead to even lower transmission rates.
将马铃薯皮副产物用于食品包装应用，尤其是替代当前基于石化产品的氧气阻隔解决方案（如乙烯 - 乙烯醇共聚物），正变得越来越重要。因此，开发了含10 - 50%（/马铃薯皮）柠檬酸（CA）的基于马铃薯皮的薄膜和涂层（涂覆在聚乳酸上）。为了确定CA浓度对流延薄膜和涂层的结构及物理化学性质的影响，进行了衰减全反射傅里叶变换红外光谱（ATR - FTIR）、水分吸附等温线、拉伸性能、透光率、氧气透过率、二氧化碳传输速率和水蒸气透过率测量。结果表明，CA浓度从10%增加到30%会增加酯化/交联作用，并在50%相对湿度下使氧气透过率达到最小值（0.08 cm m d bar），在50%→0%相对湿度下使水蒸气透过率达到最小值（1.6 g m d）；而从30%增加到50%会增加游离CA浓度并导致柔韧性增加，这表明在较高浓度下CA在薄膜/涂层中起到了增塑剂的作用。总体而言，含CA的基于马铃薯皮的涂层表现出与乙烯 - 乙烯醇共聚物相当的阻隔性能。我们认为，本研究中未进行的对马铃薯皮的广泛工业纯化或分级处理可能会导致更低的传输速率。
