Grupo de Investigación SIMERQO, Departamento de Química, Universidad del Valle, Calle 13 No. 100-00, Santiago de Cali 76001, Colombia.
Grupo de Investigación Biotecnología, Facultad de Ingeniería, Universidad de San Buenaventura Cali, Carrera 122 # 6-65, Santiago de Cali 76001, Colombia.
Molecules. 2022 Mar 31;27(7):2264. doi: 10.3390/molecules27072264.
The indiscriminate use of plastic in food packaging contributes significantly to environmental pollution, promoting the search for more eco-friendly alternatives for the food industry. This work studied five formulations (T1-T5) of biodegradable cassava starch/gelatin films. The results showed the presence of the starch/gelatin functional groups by FT-IR spectroscopy. Differential scanning calorimetry (DSC) showed a thermal reinforcement after increasing the amount of gelatin in the formulations, which increased the crystallization temperature (Tc) from 190 °C for the starch-only film (T1) to 206 °C for the film with 50/50 starch/gelatin (T3). It also exhibited a homogeneous surface morphology, as evidenced by scanning electron microscopy (SEM). However, an excess of gelatin showed low compatibility with starch in the 25/75 starch/gelatin film (T4), evidenced by the low Tc definition and very rough and fractured surface morphology. Increasing gelatin ratio also significantly increased the strain (from 2.9 ± 0.5% for T1 to 285.1 ± 10.0% for T5) while decreasing the tensile strength (from 14.6 ± 0.5 MPa for T1 to 1.5 ± 0.3 MPa for T5). Water vapor permeability () increased, and water solubility () also decreased with gelatin mass rising in the composites. On the other hand, opacity did not vary significantly due to the films' cassava starch and gelatin ratio. Finally, optimizing the mechanical and water barrier properties resulted in a mass ratio of 53/47 cassava starch/gelatin as the most appropriate for their application in food packaging, indicating their usefulness in the food-packaging industry.
在食品包装中不加区分地使用塑料会对环境污染造成重大影响，因此食品行业正在积极寻求更环保的替代品。本工作研究了五种可生物降解的木薯淀粉/明胶薄膜配方（T1-T5）。傅里叶变换红外光谱（FT-IR）表明存在淀粉/明胶的功能基团。差示扫描量热法（DSC）表明，随着配方中明胶含量的增加，出现了热增强现象，使淀粉纯膜（T1）的结晶温度（Tc）从 190°C 升高到 50/50 淀粉/明胶膜（T3）的 206°C。扫描电子显微镜（SEM）也表明其表面形态均匀。然而，在 25/75 淀粉/明胶膜（T4）中，明胶过多与淀粉的相容性较差，这表现在 Tc 定义较低且表面形态非常粗糙和断裂。随着明胶比例的增加，应变（从 T1 的 2.9±0.5%增加到 T5 的 285.1±10.0%）显著增加，而拉伸强度（从 T1 的 14.6±0.5 MPa 降低到 T5 的 1.5±0.3 MPa）显著降低。水蒸气透过率（WVTR）增加，复合材料中明胶质量增加导致水溶性（WS）降低。另一方面，由于薄膜中木薯淀粉和明胶的比例，不透明度没有显著变化。最后，优化机械和水阻隔性能得到了最适合于食品包装应用的质量比为 53/47 木薯淀粉/明胶，表明其在食品包装行业的有用性。
