Chartreuse (liqueur) was not a secret but well known. At the death of the pharmacist, his heirs returned the manuscript to the monks who had been back at the Monastery since 1816. In 1838, they developed Yellow Chartreuse, a sweeter version of the Green Chartreuse, 40% alcohol liqueur (80° proof). The monks were again expelled from the monastery following a French law in 1903, and their real property, including the distillery, was confiscated by the government. The monks took their secret recipe to their refuge in Tarragona, Catalonia, and began producing their liqueurs with the same label, but with an additional label
Lemon liqueur proof neutral spirits to extract from it the lemon oil (an essential oil). The extraction is then diluted with simple syrup. Different varieties of lemon are used to produce different flavors. The variety of lemon used is usually dictated by region. Various alcohols can be used to give distinct flavors. A higher proof alcohol maximizes extraction of the lemon flavor, whereas darker alcohols add complexity of flavor. Many commercial brands of lemon liqueur are produced in Italy, in several styles (see Italian liqueur). In Italy, especially in Campania, lemon liqueur is consumed as a chaser ("ammazzacaffè") to coffee. Lemon liqueur