Quote: The Romanian ciorbe are soups with a characteristically tangy tart aroma and taste due to the addition of a souring agent. Traditionally, a sour base called bors (not to be confused with the Russian borscht, which is a red beet soup) was used. Bors is made from fermented wheat bran, and can be prepared at home or bought at Romanian grocery stores. However, in recent years it is less frequently used because it requires too much time to prepare. Instead, the most common souring agents for the ciorbe are lemon juice and sauerkraut juice. Other souring agents are vinegar, sour grape leaves or green sorrel leaves. From Taste Of Romania by Nicolae Klepper