Selective catalysis to convert lignin-rich biomass into clean-label vanillin for plant-based dairy and beverages

The growing demand for soy, pea, oat and other plant-protein matrices to produce dairy and beverage products is driving the need for clean-label vanillin, a natural or nature-identical option that maintains sensory performance and flavor consistency in plant-protein matrices. The global demand for vanilla cannot be satisfied using natural extraction from vanilla orchid pods alone, and catalytic and biotechnological synthesis have become essential, the most important precursor for sustainable vanillin production that does not compete with food use. This review discusses the lignin structure and the yield of vanillin by catalytic routes, such as perovskites, polyoxometalates, metal oxides, LDH-based catalysts, and enzymes, and explores reaction mechanisms, catalyst stability, and industrial feasibility. We believe the key problem in the production of vanillin from food-grade lignin is not only catalytic yield, but also an intractable triangle consisting of vanillin selectivity, the transition metal catalyst residue in the product and compliance with food safety regulations. The most promising path towards industrial use of these systems is a combination of LDH-derived mixed oxides and enzyme-based catalytic systems, and the clean-label plant-based dairy and beverage industry seems to be the testbed for these catalytic systems.