Alkaline fruits include oranges, bananas, cherries, mangoes, longan, peaches, cantaloupes, papaya, apples, watermelons, strawberries, blueberries, guava, grapes, lemons and plums. The main components of alkaline fruit (calcium, sodium, potassium and magnesium) are four essential elements for human exercise. Although the taste of these fruits is mostly sour, they will become alkaline during metabolism in the body.