Abstract This study presents the valorization of the Gelidium sesquipedale seaweed for the development of bioactive aerogels with interest in food packaging applications. The raw seaweed was used to extract cellulose, highly crystalline (Xc∼70%) and high aspect ratio (∼40) nanocellulose and an agar-based extract, rich in polyphenols and with antioxidant capacity. Subsequently, pure PVA and hybrid aerogels containing cellulose and nanocellulose were produced by a physical cross-linking method. The presence of hydroxyl groups provided by the high aspect ratio of nanocellulose promoted the interactions with water and facilitated the accessibility of moisture towards the interior of the aerogels, hence generating high water sorption capacity materials. The agar-based extract was then incorporated into selected formulations and the release in hydrophobic and hydrophilic food simulant media was investigated. Pure PVA aerogels dissolved in aqueous media, resulting in an immediate release of the bioactive. Interestingly, the hybrid aerogels containing cellulose and nanocellulose preserved their integrity and provided a more gradual release. Although the hybrid aerogels presented similar release profiles during the first 48 h, the presence of nanocellulose led to greater release values after more prolonged times. This shows the promising properties of hybrid PVA/cellulose/nanocellulose aerogels as matrices for the controlled release of bioactive compounds in food systems, which could be of interest for the development of bioactive packaging structures.

中文翻译：

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通过石花菜海藻的价值开发食品包装生物活性气凝胶

摘要 本研究介绍了 Gelidium sesquipedale 海藻的价值，用于开发对食品包装应用感兴趣的生物活性气凝胶。生海藻被用来提取纤维素、高度结晶（Xc~70%）和高纵横比（~40）的纳米纤维素和一种琼脂提取物，富含多酚并具有抗氧化能力。随后，通过物理交联方法制备了纯 PVA 和含有纤维素和纳米纤维素的混合气凝胶。纳米纤维素的高纵横比提供的羟基的存在促进了与水的相互作用，并促进了水分向气凝胶内部的可及性，从而产生了高吸水能力的材料。然后将基于琼脂的提取物掺入选定的制剂中，并研究在疏水性和亲水性食品模拟介质中的释放。纯 PVA 气凝胶溶解在水性介质中，导致生物活性物质的立即释放。有趣的是，含有纤维素和纳米纤维素的混合气凝胶保持了它们的完整性并提供了更渐进的释放。尽管混合气凝胶在前 48 小时内表现出相似的释放曲线，但纳米纤维素的存在导致更长时间后更大的释放值。这显示了混合 PVA/纤维素/纳米纤维素气凝胶作为用于食品系统中生物活性化合物受控释放的基质的有希望的特性，这可能对生物活性包装结构的开发感兴趣。