Making green vanilla

Despite increasing consumer demand for more ‘natural’ foods, less than 1% of vanilla flavour produced globally comes from its original natural source, the vanilla orchid. The rest is synthesised from a petroleum-derived precursor called guaiacol, tree lignin and other substances such as cow faeces.

Making vanilla flavour synthetically creates a stream of wastewater that requires treatment before it can be released into surface waters. So researchers have developed an improved method to make vanillin, the primary flavour compound in vanilla.

As reported in ACS’s journal Industrial & Engineering Chemistry Research, Ganapati D Yadav and Shivaji L Bhanawase created a catalyst by encapsulating copper-aluminium hydrotalcite in silica. Testing showed that it efficiently spurred the separation of vanillin from other compounds. The catalyst worked in water under ambient air pressure and eliminated the need for a polluting step involving hydrochloric acid that current techniques require. The catalyst could also be recovered and re-used, unlike current catalysts that can only be used once.

The researchers say that their process could be economically scaled up for a more environmentally friendly approach to making commercial vanillin.