Pineapple ripened or off-green. A plant growth regulator, Ethephon, is typically sprayed onto the fruit one week before harvest, developing ethylene, which turns the fruit golden yellow. After cleaning and slicing, a pineapple is typically canned in sugar syrup with added preservative. A pineapple never becomes any riper than it was when harvested. The fruit itself is quite perishable and if it is stored at room temperature, it should be used within two days; however, if it is refrigerated, the time span extends to 5–7 days. Mimi Sheller writes: "The pineapple entered European iconography as a symbol of welcome and hospitality,
Hospitality service Servas International, the first hospitality service, as a volunteer-run international nonprofit organization advocating interracial and international peace. In 1953, several European teachers who wanted to travel internationally during their summer breaks founded Intervac International, a home exchange network. In 1965, John Wilcock set up the Traveler's Directory as a listing of his friends willing to host each other when traveling. In 1988, Joy Lily rescued the organization from imminent shutdown, forming Hospitality Exchange. In 1966, psychologist Rubén Feldman González created Programo Pasporto, a hospitality service for Esperanto speakers in Argentina. In 1974, with the help of Jeanne-Marie Cash, it became