A pile of oranges in the wholesale market in Chiang Mai.
One of the first tastes a new visitor gets of Thailand is the mildly sweet flavor of fresh orange juice with their morning breakfast. Thai oranges are sweet and low on acid, which makes for a smooth and sweet drink.
The most common type of Thai oranges aren't much to look at, but their common Thai name, which translates to "sweet green orange", pretty much says it all. The rather smooth and thin skin is typically greenish in hue with yellow blotches, or yellow-orange with green blotches, depending on how you look at it. Thais are less obsessed with the outer appearance of fruits and other foods than westerners. Oranges don't have to have a perfectly unblemished skin, they just have to taste good.
Also easily found is a fruit with a bright lime green skin that nonetheless has orange flesh and a strong sweet orange taste. All citrus fruits originated in South-east Asia, although exactly where each strain comes from is lost in the mists of time. Citrus was already a part of traditional Chinese medicine by the first century A.D.
Perhaps even more so than in the west, Thais generally juice their oranges rather than eating the fruit directly. Thais prefer their juice fresh squeezed, rather than processed, packaged or frozen. You can find packaged juice in the supermarket, but just about everyone agrees that it doesn't taste the same.