Beer-Lech Karolina, Skic Anna, Skic Kamil, Stropek Zbigniew, Arczewska Marta
Department of Mechanical Engineering and Automatic Control, University of Life Sciences in Lublin, 28 Głęboka St., 20-612 Lublin, Poland.
Institute of Agrophysics, Polish Academy of Sciences, 4 Doświadczalna St., 20-290 Lublin, Poland.
Materials (Basel). 2022 Jun 24;15(13):4459. doi: 10.3390/ma15134459.
The research subject was the analysis of the microstructure, barrier properties, and mechanical resistance of the psyllium husk (PH)-modified thermoplastic starch films. The tensile tests under various static loading conditions were not performed by researchers for this type of material before and are essential for a more precise assessment of the material's behavior under the conditions of its subsequent use. The film samples were manufactured by the casting method. PH addition improved starch gelatinization and caused a decrease in failure strain by 86% and an increase in failure stress by 48% compared to pure films. Fourier transform infrared spectroscopy results showed the formation of additional hydrogen bonds between polysaccharides in starch and PH. An increase in the number of hydrophilic groups in the modified films resulted in a faster contact angle decrease (27.4% compared to 12.8% for pure ones within the first 5 s); however, it increased the energy of water binding and surface complexity. The modified films showed the opacity at 600 nm, 43% higher than in the pure starch film, and lower transmittance, suggesting effectively improving barrier properties to UV light, a potent lipid-oxidizing agent in food systems.
研究对象是对车前子壳（PH）改性热塑性淀粉薄膜的微观结构、阻隔性能和机械抗性进行分析。此前研究人员未对这类材料在各种静态加载条件下进行拉伸试验，而该试验对于更精确评估材料在后续使用条件下的行为至关重要。薄膜样品通过流延法制造。与纯薄膜相比，添加PH改善了淀粉糊化，使断裂应变降低了86%，断裂应力提高了48%。傅里叶变换红外光谱结果表明，淀粉中的多糖与PH之间形成了额外的氢键。改性薄膜中亲水基团数量的增加导致接触角下降更快（在前5秒内，与纯薄膜的12.8%相比下降了27.4%）；然而，这增加了水结合能和表面复杂性。改性薄膜在600纳米处呈现不透明度，比纯淀粉薄膜高43%，且透光率更低，这表明其有效改善了对紫外线的阻隔性能，紫外线是食品体系中一种强大的脂质氧化剂。
