USE OF ORGANIZED VIABLE VANILLA PLANT AERIAL ROOTS FOR THE PRODUCTIONOF NATURAL VANILLIN

A novel process for producing natural vanillin flavour from ferulic ac id precursor has been developed based on the use of vanilla plant aeri al roots as the biocatalyst. The charcoal used in the process acts as a product reservoir for the vanillin produced, thus relieving possible product inhibition and/or further metabolism. The vanillin is then re moved from the charcoal by selective solvent extraction. Remaining unr eacted ferulic acid remains adsorbed to the charcoal and can be recycl ed for further reaction. The aerial root tissue can be reused several times, although its activity gradually declines with reuse. Vanillin p roductivities of 400 mg kg(-1) dry wt tissue day(-1) and concentration s of 7 g kg(-1) of root tissue can be regularly obtained. This concent ration is ca 35-fold greater than the concentrations of vanillin origi nally present in the aerial root tissue and is about 40% of that prese nt in matured vanilla beans. Using aerial roots supplied with ferulic acid, vanillin is produced 5-10 times faster than its normal synthesis in vanilla beans, or in aerial roots that have not been supplied with precursor. The composition of the vanilla flavour produced using the aerial root method is comparatively close to that of vanilla beans; in particular it contains p-hydroxybenzaldehyde, at a vanillin:pHB ratio of 7.8:1, as compared to a ratio of 12.8:1 for bean-derived vanilla. This may impart a superior organoleptic value and make the product of this aerial root process more valuable.