Components, Processing Characteristics and Aroma of Xinjiang Qiamagu (Brassica rapa L.) Powder Prepared by Different Drying Methods

Qiamagu (Brassica rapa L) is a plant that can be used both as an edible and medicinal plant. Qiamagu powder is a common form of processed product, which can be used as an ingredient in direct edible products or other products. In order to understand the influence of different drying methods on the quality of Qiamagu powder, this paper took Qiamagu produced in Pamir Plateau of Xinjiang as raw material, and used five drying methods: Natural drying (ND), cold air drying (CD), hot air drying (HD), vacuum drying (VD) and freeze-drying (FD) to dry Qiamagu slices, and then mashed them to Qiamagu powder. The main nutritional components, physical properties and processing characteristics of Qiamagu powder were analyzed and tested. The aroma components of the powder were analyzed by electronic nose and GC-MS. The results showed that the FD powder maintained completely all nutrient components of Qiamagu, especially V_C and protein content, followed by CD powder. The color of FD powder was milky white with brightness L^* being 90.31. The browning of FD powder was the least, followed by CD powder. The solubility of FD powder was the lowest (0.055 g/g), and its stability was good (0.068%). The types and relative contents of aroma components in FD powder were the most, followed by CD powder. Therefore, FD had better retention of the Qiamagu flavor. In summary, FD could be used as the preferred drying method for producing high-quality Qiamagu powder. Considering the cost of industrial production, CD could be used as a better alternative drying method.