Comparative Study on the Quality of Different Varieties of Dendrobium officinale

This study compared the quality of different varieties of Hongxin Dendrobium officinale (D. officinale) (Hongxin No.1 green pole, Hongxin No. 1 red pole, hongxin no. 5 red pole), such as the hardness, shear force and shear displacement, viscosity and consistency, sensory score, color difference value;the content of polysaccharide, molecular weight, monosaccharide, flavonoids and alkaloids. Meanwhile, this study explored the relationship between the quality and texture of D. officinale before and after pulping. The results showed that the hardness, shear force, the molecular weight of polysaccharide, consistency and color difference of three D. officinale samples were significantly different. The polysaccharide was a heterogeneous component, which was heteropolysaccharide. The content of polysaccharide in Hongxin No.1 red pole was the highest, followed by Hongxin No.1 green pole and Hongxin No.5. The monosaccharide composition of polysaccharides was basically the same, mainly composed of 4 six-carbon sugars (mannose, glucose, galactose, rhamnose) and 3 five-carbon sugars (ribose, arabinose, xylose), among which the content of mannose and glucose was the highest, followed by arabinose, but the relative content was different. Among them, the relative content of mannose in hongxin NO.1 red rod was the highest (46.71%), while that in hongxin no.1 green rod was 36.52%, and that in hongxin NO.5 red rod was 35.92%. There was no significant difference in moisture content, shear displacement and the sensory score of three D. officinale samples. The content of polysaccharide in dry D. officinale before beating was positively correlated with its texture (the hardness, shear force and shear displacement), while the content of polysaccharide in D. officinale was positively correlated with its consistency. The results showed that the quality of D. officinale was significantly different from that of D. officinale from the place of the the same origin, the same series, and different varieties.