Use of polysaccharide-based aerogels in iced tea clarification process

Polysaccharide-based aerogels, particularly those produced from chitosan and xanthan gum, offer a sustainable and efficient alternative for clarifying ready-to-drink (RTD) tea infusions. In this study, the aerogels were applied to black and green teas to reduce turbidity and tea cream formation during 20 days of storage. Key quality attributes were evaluated, including clarity (transmittance, tea cream), color (L*, a*, b*, ΔE), and catechin content. Water mobility assessed by NMR relaxation and diffusion, molecular interactions with tea components examined by FTIR. Chitosan aerogels significantly reduced cream formation and helped maintain color stability in black tea. In green tea, however, they caused more noticeable color changes, reflected by higher ΔE values, though catechin losses remained moderate. FTIR results showed surface-level interactions between aerogels and tea components such as proteins and polyphenols. NMR relaxometry also indicated reduced water mobility after treatment, supporting surface adsorption. Xanthan gum aerogels produced similar clarity improvements, although color shifts were slightly more pronounced in green tea. Despite these effects, both aerogels preserved essential quality characteristics. Overall, food-grade polysaccharide aerogels serve as effective alternatives to conventional adsorbents. Their porous structure allows selective removal of turbidity-related compounds, while their easy handling and biodegradability make them promising options for beverage clarification. • Polysaccharide aerogels clarified ready-to-drink teas by reducing haze • Chitosan aerogels kept black tea clear with minimal color alterations • Green tea showed greater color shifts, while catechins were preserved • Aerogels are eco-friendly, easy to remove, and effective over silica • NMR and FTIR confirmed selective adsorption of haze-forming compounds