Arrowroot is a fine, easily digested starch obtained from the rhizomes of Maranta arundinacea, a tropical plant of the West Indies. Neutral in flavour, it has long served as a thickener in invalid and infant diets, and it thickens fruit sauces, pie fillings, and desserts while leaving a prized clear, glossy finish rather than the cloudy gel of some cereal starches. The name is also applied to starches from several other tropical rhizomes used in similar ways. Because arrowroot starch contains no gluten and forms smooth, stable gels, it suits gluten-free cooking and delicate sauces, though its relatively high cost compared with corn or cassava starch keeps it a speciality thickener.