ARROWROOT powder is the ground dried rhizome of the arrowroot plant. It is used as a thickener and has a very neutral flavour. It is good for delicately flavoured sauces, and for clear sauces, as it won't turn cloudy. It also works best at a low temperature, and tolerates acidic ingredients and prolonged cooking. It is not a good thickener for dairy-based sauces, as it turns them slimy. It is a great substitute for flour (arrowroot is gluten free!) in thickening gravy and in a traditional roux.