**6.1 Stability and preservation**

The stability of polyphenols during processing, storage, and in the presence of other food components is one of the greatest obstacles to utilising polyphenols to enhance lipid quality. Polyphenols are susceptible to degradation and oxidation, which result in diminished efficacy and bioactivity. Strategies to improve polyphenol stability, such as encapsulation techniques and the development of protective delivery systems, require investigation [35, 36].

Although numerous extraction techniques have been devised, achieving high extraction yield and efficiency remains a challenge. Optimal polyphenol extraction necessitates the optimization of extraction parameters, the selection of suitable solvents, and the investigation of innovative extraction techniques [37].

The selective extraction of particular polyphenols from complex food matrices is a challenge that must be addressed. Different polyphenols exhibit distinct bioactivities, and the extraction selectivity of these polyphenols can affect the final product's desired functional properties. It is of interest to develop extraction methods that target specific polyphenols while preserving integrity [27, 37].

### **6.2 Standardisation and quality control**

Standardisation of polyphenol extraction protocols and the establishment of quality control measures are required to ensure consistent and reliable extraction results. The development of analytical methods and the establishment of quality standards will contribute to the reproducibility and comparability of research findings [38].

### **6.3 Sustainability and green technologies**

As the demand for sustainable and environmentally benign practices increases, it is necessary to develop green extraction technologies that minimise energy consumption, solvent usage, and refuse production. The investigation of alternative solvents, such as supercritical fluids and natural deep eutectic solvents, can provide environmentally preferable alternatives for polyphenol extraction [39].
