Sol-gel microencapsulation of odorants and flavors: opening the route to sustainable fragrances and aromas.

The sol-gel approach to encapsulate fragrance and aroma chemicals in porous silica-based materials has the potential to afford odorant and flavoured materials with novel and unique beneficial properties. Amorphous sol-gel SiO2 is non-toxic and safe, whereas the sol-gel entrapment of delicate chemicals in its inner pores results in pronounced chemical and physical stabilization of the entrapped actives, thereby broadening the practical utilization of chemically unstable essential oils. Reviewing progress in the fabrication of diverse odorant and flavoured sol-gels, we show how different synthetic strategies afford advanced materials suitable for practical application with important health and environmental benefits.