Phytochemical composition and nutritional characterization of qamgur (Brassica rapa L.) in different forms

Abstract

The purpose of this paper is to determine the phytochemical composition and evaluate the nutritional value of qamgur (Brassica rapa L., a characteristic crop in Xinjiang). The fresh qamgur was processed with hot air drying and freeze drying and then sliced into FD qamgur slices and ground into qamgur powders. The results show that qamgur powders and FD qamgur slices are rich in the nutrients essential for human health, such as total sugar (41.4 and 44.8 g/100 g), polysaccharide (16.3 × 10 3 and 20.4 × 10 3 g/100 g), Vitamin C (39.3 and 46.5 g/100 g), flavonoids (45.0 and 33.0 g/100 g) and total saponins (46.0 and 30.0 g/100 g) compared with the fresh qamgur. Moreover, major elements and micro elements analysis were measured by inductively coupled plasma atomic emission spectrometry (ICP-AES), and the results showed that an abundant number of mineral elements (e.g. K, Na, Ca, Mg, Cu, Fe, Zn and Mn) were found in qamgur. The content of Ca was 4.5×10 3 mg/kg, 15.7 mg/kg for Zn, and 81.1 mg/kg for Fe. Similarly, the highest protein value was observed in the qamgur powders (12.4 g/100 g), whereas the fresh samples contained only 2.78 g/100 g. In addition, the proportion of essential amino acids (EAA) and nonessential amino acids (NEAA) of the powders were 59.7% and 40.3%, whereas for the FD slices, they were 61.0% and 39.0%. Overall, the nutritional value of qamgur was significantly improved through processing. So, in this paper, we provide the theoretical basis for the study on the nutritional value of qamgur and the development of medicinal foods and functional foods.