Anisyl alcohol is an important spice in flavouring industries. However, its volatility makes it easy to degrade in high-temperature pretreatment, thus limiting its wider application in tobacco industry and food reheating. To develop thermal stable flavour of this spice, a novel flavour precursor anisalcohol-β-galactoside was synthesised by glycosylation reaction, using anisyl alcohol and D-lactose as substrates and recombinant β-galactosidase as catalyst. The thermal decomposition process was determined by thermogravimetric analysis (TGA). TG curves revealed the maximum weight loss of anisyl alcohol reached 75% between 90 and 190 °C, while that of anisicohol-β-galactosidase was only 54% between 240 and 360 °C, which was an even higher range of temperature. The optimisation in thermal behaviour of anisicohol-β-galactosidase made it prospectively available in high-temperature pretreatment and provided a new method for thermal stability improvement of other similar spices.