Galliano uses vanillin for flavouring and sugar and glucose syrup for sweetening. It is often sweetened by adding molasses or other sweetening agents. Blue-agave syrup contains 56% fructose as a sugar providing sweetening properties. Sucrose which is disaccharide is usually used as a sweetening agent. Two 2010 review studies found no health concerns with stevia or its sweetening extracts. The major changes include fruit softening, sweetening, decreased bitterness, and colour change. The flavour of Yanjiang dishes is often enhanced by sweetening and smoking. In 1989 a gas sweetening plant and sulfur processing unit were added. Fuels desulfurized by copper sweetening also contain a significant trace amounts of copper. Another product removed during sweetening is carbonyl sulfide. A shorter or longer spacer reduces the sweetening effect. For Genever and Gin, they shall not contain more than two percent sweetening agents. Related processes are known as sweetening. The series was taped in front of a live studio audience with some sweetening.