Olive oil regulation and adulteration phenolphthalein as a pH indicator dye. The base stock solution was titrated to neutralize an equal quantity of the acid, so without the presence of vegetable oil it would require 40 milliliters of acid to cause a color change, but in the pure oils tested (almond, benne, cottonseed, cod liver oil, linseed oil, and olive oil, only 6 milliliters were required. In accordance with this, olive oil adulterated with 10% mineral oil required 8 milliliters, and with 20% 11 milliliters. The adulterated oil tested in 1887 required 14 to 17 milliliters to neutralize, so it might have been 30-40% mineral
Narva Oil Plant Narva Oil Plant Narva Oil Plant (), a subsidiary of Eesti Energia, is a producer of shale oil from oil shale. It operates a commercial scale shale oil retorting plant, located in Auvere near Narva, Estonia. The oil shale retorting plant (the UTT-3000 refinery) was built in the late 1970s next to the Eesti Power Plant to provide shale oil as a start-up fuel for the power plants. The plant was commissioned in 1980. Since the beginning of the 1990s, the oil plant operated as a part of the Narva Power Plants. In September 2007, the oil plant was separated