According to the Italian food company Barilla, orzo can be substituted with Arborio rice. The word orzo means barley in Italian, but orzo pasta does not contain barley; it is usually made with Durum wheat flour, also referred to as semolina.
Orzo is shaped like a grain of rice; it has a firm texture. The natural color of orzo is off-white. Often served in soups or chilled in salads, some orzo uses vegetable extract to change its natural color. Gluten-free orzo made with quinoa, lentil and other flours are also available. Other substitutes for orzo are fregola pasta and couscous, depending on the dish being prepared; these pastas and grains are interchangeable.