Cola by citric or other isolated acids. Coca-Cola's recipe is maintained as a corporate trade secret. A variety of different sweeteners may be added to cola, often partly dependent on local agricultural policy. High-fructose corn syrup (HFCS) is predominantly used in the United States and Canada due to the lower cost of government-subsidized corn. In Europe, however, HFCS is subject to production quotas designed to encourage the production of sugar; sugar is thus typically used to sweeten sodas. In addition, stevia or an artificial sweetener may be used; "sugar-free" or "diet" colas typically contain artificial sweeteners only. In the 1940s, Coca-Cola
Coca-Cola with Lime Ireland along with the Diet version; however, now only the Diet Coca-Cola with Lime variety remains on sale in that country. Coca-Cola Citra is available in Japan. Coca Cola with Lime was briefly available in Australia, but proved quite unpopular with some larger retailers such as Woolworths and Coles, who bought in bulk, having to reduce the price considerably (50c for a 1.25 L bottle compared to around A$2 for all other varieties) in order to clear the product out. Diet Coke with Lime was discontinued in the United Kingdom, as was Diet Coke with Lemon in the beginning of