They have a tart, sour undertone, and an oxalic acid odor. The taste is difficult to match, but it has been compared to a mix of apple, pear, grape, and citrus family fruits. Unripe star fruits are firmer and sour, and taste like green apples. Ripe carambolas may also be used in cooking.You can add this fruit to your diet in many ways, including: Slice and eat it on its own. Add it to salads or other fresh dishes. Use it as a garnish. Turn it into pies or puddings. Add it to Asian- or Indian-style stews and curries. Cook it with seafood or shellfish dishes. Make jam, jelly, or chutney.