Potato flour. According to knowledgeable people, raw flour refers to starch in Chinese food, which is a term that often appears in recipes. It is often used for thickening, hanging pulp and cooking. The raw flour used in Chinese mainland and Taiwan Province provinces of China is potato flour, while the raw flour used in China and Hongkong generally refers to the windmill super raw flour (potato starch) and chestnut flour (corn starch) imported from Europe.