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,
Heart (symbol) depicted in ecclesiastical heraldry, and hearts representing love appearing in bourgeois coats of arms. Hearts also later became popular elements in municipal coats of arms. There has been some conjecture regarding the link between the traditional heart symbol and images of the fruit of Silphium, a (probably) extinct plant known to classical antiquity and belonging to the genus Ferula, used as a condiment and medicine, (the medicinal properties including contraceptive and abortifacient activity, linking the plant to sexuality and love). Silver coins from the ancient Libya of the 6th - 5th BC bear images strongly reminiscent of the heart symbol,