The Tequila Volcano blue mushroom (Lactarius indigo), also called the indigo milk cap, the indigo (or blue) lactarius and the blue milk mushroom, is known in the region by the common names quexque, riricacha, añil, oreja de puerco azul and zuin. Some nicknames relate to its unusual coloring, like "pants mushroom," because the blue is reminiscent of blue jeans.
Lactarius indigo grows in west-central Mexico as well as other parts of North and Central America and eastern Asia. The fruiting body rises 8 centimeters (3 inches) above the ground, with a cap measuring up to 15 centimeters (6 inches) in diameter. A distinctive dark blue color, as it ages it takes on a slightly grayish hue.
The mushroom contains iron, protein and calcium and is low in calories, carbohydrates and fat. Slight laxative properties have been associated with its consumption.
Stir-frying is the best cooking method to preserve its bright color, but the local community mainly eats it in salads, stews and soups. Once dried on rocks in the sun, the Tequila Volcano blue mushroom can be stored for long periods. Even up to a year after harvesting, the mushrooms can be cooked after simply rehydrating them in hot water.
Blue mushrooms are a seasonal delicacy that are harvested on the slopes of the volcano from July to August, during the rainy season. In recent years, interest in the species has increased: Mycotourism has led to an appreciation of the area and local ecological knowledge. Today in Tequila, experienced mycologists work with communities to pass on ancient collecting techniques. In the past, this knowledge was passed down through generations, mainly by women.
The mushrooms used to be frequently cooked by the inhabitants of this area of the Valles region of Jalisco, but over the years their use has become less common. A few passionate locals have kept the traditional recipes alive, however, preserving traditional knowledge and skills.