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The genus Vanilla belongs to the family Orchidaceae, which is one of the largest families of flowering plants in the world comprising 788 genera and 18 500 species. The genus itself contains over 100 species (Mabberley, 1997). V. planifolia is the only orchid that is of direct economic importance because it is the main source of the vanilla aroma. This aroma is widely used in the pharma, food, and cosmetic industry. V. planifolia has its origin in Mexico, where it was already brought by Spanish to Europe in 1520 and it became very popular. V. planifolia is still the only natural source of the vanilla aroma. In some other plants (narcissus, hyacinth, potato) traces of vanillin occur (Havkin‐Frenkel et al., 1999). Vanillin normally present in conjugated form as β‐D‐glucoside at a concentration of 1.0–2.0% of dry matter in cured vanilla pods (Westcott et al., 1993). The vanilla aroma develops in the pods or beans through a quite labor‐intensive process called curing. This process for aroma development is carried out to dry the vanilla beans and to allow chemical and enzymatic reactions to occur. Curing process aims to arrest the vegetative growth and induces the changes responsible for aroma formation. Generally, curing comprises three stages such as killing/scalding, sweating/sunning, drying, and conditioning/packaging. During curing process, conjugated glycoside molecules accumulated in the green pods are hydrolyzed enzymatically by induced β‐D‐glucosidases through drying and heating. Further packaging of processed pods by storing in closed boxes for few months facilitates various biochemical reactions such as esterification, etherification, oxidative degradation, etc. that results in desired aroma and flavor formation (Rao and Ravishankar 2000; Converti et al., 2010). Conventionally by curing process very less (1–2%) vanillin is produced naturally (Sinha et al., 2008). Moreover, natural vanillin production using plant sources is laborious, time consuming, and also expensive. With the increasing interest in producing natural vanillin and the insufficiency of plant‐derived natural vanillin production to meet the demand, alternative processes are developed to produce vanillin from a natural raw resources through many biotechnological approaches including enzyme catalyzed conversions, microbial bioconversions, the development of tissue cultures, and genetic/metabolic engineering.