Tessaro Larissa, Pereira Ana Gabrielle R, Martelli-Tosi Milena, Sobral Paulo José do Amaral
Department of Food Engineering, Faculty of Animal Science and Food Engineering, University of São Paulo, Av Duque de Caxias Norte, 225, Pirassununga 13635-900, SP, Brazil.
Food Research Center (FoRC), University of São Paulo, Rua do Lago, 250, Semi-Industrial Building Block, São Paulo 05508-080, SP, Brazil.
Foods. 2024 May 10;13(10):1480. doi: 10.3390/foods13101480.
Biopolymer-based films can be activated by the incorporation of active compounds into their matrix. Plant extracts are rich in phenolic compounds, which have antimicrobial and/or antioxidant properties. The aim of this study was to produce gelatin-based active films and nanocomposite films incorporated with "pitanga" ( L.) leaf extract (PLE) and/or crystalline nanocellulose extracted from soybean straw (CN), and to study the physicochemical, functional, microstructural, thermal, UV/Vis light barrier, and antioxidant properties of these materials. PLE enhanced some film properties, such as tensile strength (from 30.2 MPa to 40.6 MPa), elastic modulus (from 9.3 MPa to 11.3 MPa), the UV/Vis light barrier, and antioxidant activity, in addition to affecting the microstructural, surface, and color properties. These improvements were even more significant in nanocomposites simultaneously containing PLE and CN (59.5 MPa for tensile strength and 15.1 MPa for elastic modulus), and these composites also had lower moisture content (12.2% compared to 13.5-14.4% for other treatments) and solubility in water (from 48.9% to 44.1%). These improvements may be the result of interactions that occur between PLE's polyphenols and gelatin, mainly in the presence of CN, probably due to the formation of a stable PLE-CN-gelatin complex. These results are relevant for the food packaging sector, as the activated nanocomposite films exhibited enhanced active, barrier, and mechanical properties due to the presence of PLE and CN, in addition to being entirely produced with sustainable components from natural and renewable sources.
基于生物聚合物的薄膜可以通过将活性化合物掺入其基质中来激活。植物提取物富含具有抗菌和/或抗氧化特性的酚类化合物。本研究的目的是制备掺入“针叶樱桃”（番樱桃）叶提取物（PLE）和/或从大豆秸秆中提取的结晶纳米纤维素（CN）的明胶基活性薄膜和纳米复合薄膜，并研究这些材料的物理化学、功能、微观结构、热学、紫外/可见光阻隔和抗氧化性能。PLE除了影响微观结构、表面和颜色性能外，还增强了一些薄膜性能，如拉伸强度（从30.2MPa提高到40.6MPa）、弹性模量（从9.3MPa提高到11.3MPa）、紫外/可见光阻隔性能和抗氧化活性。在同时含有PLE和CN的纳米复合材料中，这些改善更为显著（拉伸强度为59.5MPa，弹性模量为15.1MPa），并且这些复合材料的水分含量也较低（12.2%，而其他处理为13.5 - 14.4%）以及在水中的溶解度（从48.9%降至44.1%）。这些改善可能是PLE的多酚与明胶之间相互作用的结果，主要是在CN存在的情况下，可能是由于形成了稳定的PLE - CN - 明胶复合物。这些结果与食品包装行业相关，因为由于PLE和CN的存在，活性纳米复合薄膜表现出增强的活性、阻隔和机械性能，此外还完全由天然和可再生来源的可持续成分制成。
