易腐食品在运输过程中的大量浪费极大地促进了温室气体的排放,加剧气候危机。为了减轻水果的快速腐败,使用天然蛋清(EW)开发了一种环保双层膜,直链淀粉(Am),和单宁酸(TA)。EW/Am-TA双层膜具有两亲性EW的主要层,确保疏水性水果表面的均匀涂层,以及由Am和TA组成的第二层,赋予显著的拉伸强度(5.3±0.5MPa)和断裂伸长率(28.5±4.1%)。这种双层膜有效地保护水果免受UV-B和UV-C辐射(在280和330nm下的〜0%透射率),并由于TA的存在而表现出抗氧化和抗菌性能。水果如香蕉,鳄梨,还有樱桃番茄,当浸涂优化的EW/Am-TA双层时,保持他们的新鲜度,颜色,体重,和质地长达七天,证明这种双层涂层在食品保存中的有效性。涂膜中的天然材料是可食用的,可以在室温下在<10s内用自来水安全去除,不存在食品安全风险。因此,所提出的双层涂层为全球食物浪费问题提供了重要的解决方案。
The substantial waste of perishable foods during transportation significantly contributes to greenhouse gas emissions, intensifying the climate crisis. To mitigate the rapid spoilage of fruits, an eco-friendly bilayer film was developed using natural egg white (EW), amylose (Am), and tannic acid (TA). The EW/Am-TA bilayer film features a primary layer of amphiphilic EW, ensuring a uniform coating on hydrophobic fruit surfaces, and a secondary layer composed of Am and TA, imparting notable tensile strength (5.3 ± 0.5 MPa) and elongation at break (28.5 ± 4.1 %). This bilayer film effectively shields fruits from UV-B and UV-C radiation (~0 % transmittance at 280 and 330 nm) and exhibits antioxidant and antibacterial properties due to the presence of TA. Fruits such as bananas, avocados, and cherry tomatoes, when dip-coated with the optimized EW/Am-TA bilayer, maintained their freshness, color, weight, and texture for up to seven days, demonstrating the effectiveness of this bilayer coating in food preservation. The natural materials in the coated film are edible and can be safely removed with tap water at room temperature in <10 s, posing no food safety risks. Thus, the proposed bilayer coating presents a significant solution to the global problem of food waste.