Kilju () is the Finnish word for fermented water. It is made of sugar, yeast, and water. Historically, it was called sugar wine. It often has additives such as citrus fruits, apples, berry juices, or artificial flavorings for legal reasons. Cultural aspects Kilju is considered to be a low-quality beverage that is consumed mainly for the sake of its alcohol content. It is commonly associated with the punk subculture. The Finnish Alcoholic Beverages Act 1 March 2018 legalized the manufacture of kilju and wine from fruits, berries and other carbohydrate sources, without the pretense of making proper wine. Distilling the produce into pontikka (moonshine) is however still illegal, and can lead to stiff penalties of up to four years in prison if considerable quantities were to be sold. Due to its low cost, unrefined taste and simple production process, kilju is mostly drunk by low-income people. Alternatively it can be made as a carbonated soft drink when served before the fermentation process is complete. Kilju made this way is high in sugar and carbon dioxide (CO2) content, and has little to no alcohol, being similar to a sweet lemon soda. It is a family tradition to many. The simple production process also makes it accessible to underage drinkers. Cf. sima, commonly seasoned with lemon and unpurified cane sugar, leading to a small beer or a light mead. The first commercially produced kilju was introduced in 2022. Production Kilju can be produced by fermenting sugar, yeast, and water, but kilju made exclusively from sugar, yeast, and water was illegal in Finland before March 2018; therefore, grain, potatoes, fruits or berries were used during fermentation to avoid legal problems and to flavor the drink. Oranges and lemons are a popular choice for this purpose. The process is similar to that of homebrewing wine. If done slowly, it requires rigorous hygiene and filtering of the product. If brewed fast, specialized dried yeasts are available in amounts to drive the fermentation process through before bacterial infiltration can take place, in about three days. In Finnish the latter are called pikahiiva (lit. quick-yeast), and they are sold in about a hundred gramme packs dry, as opposed to the live standard pack of brewer's yeast of 50g wet. Properly made kilju is a clear, colorless or off-white liquid with no discernible taste other than that of ethanol. It can be produced by natural settling of the