Study On Extraction Of Rose Polysaccharide And Preparation Of Funtional Beverage

Rose, a kind of medicinal edible flowers, can be potentially used as a kind of functional food, since it process a lot of beneficial activities. These including anti-aging,free radicals eliminating and antioxidant activity. The main contents and results of this study are listed as follows:Rose was used as the raw material, the rose polysaccharide was extracted by hydrothermal method and ultrasonic assisted hydrothermal extraction method. The extraction condition of these two extraction methods were optimized by single factor and orthogonal experiment. The results showed that, the best extraction conditions of hydrothermal method were extraction temperature of 60℃, extraction period of 3h, the solid to liquid ratio of l:30(g/mL), the ethanol concentration of 70%. Similarly, the optimized extraction condition for the ultrasonic assisted extraction hydrothermal extraction were ultrasonic temperature of 50℃, extraction period of 20min, the solid to liquid ratio of 1:55(g/mL), the ultrasonic power of 300w. According to the yield from the optimum condition, the results indicated that the ultrasonic assisted extraction method (with a yield of 13.48%) was superior to that of the other method (with a yield of 9.21%).The extracted rose polysaccharide was initially purified by ethanol precipitation to removed protein and pigment. The freeze dried sample was further purified by DEAE-A25 column chromatography and G-200. Finally the high purified polysaccharide of 87% was obtained by vacuum freeze drying.The in vitro antioxidation experiment of polysaccharide with various purity was firstly studied. The result showed that the clearance rate of 1,2- diphenyl generation bitter hydrazine free radicals(DPPH-), hydroxyl free radicals(·OH), and ultra oxygen anion were 68.3%, 80.3%, 70.4%, respectively. Subsquently, the internal anti-aging activity of the rose polysaccharide was studied by calculating the half lifespan, maximum lifespan and mean lifespan. The results showed that, with the increase of rose polysaccharide concentration,both the fruit flies maximum lifespan and mean lifespan were prolonged, the activities of SOD and CAT were enhanced and the content of MDA decreased. It could thus be concluded that rose polysaccharide processes with obvious anti-aging capacity.Furthermore,a functional beverage was developed by using the rose polysaccharide and orange peel as raw material. The best formula of beverage was designed by the orthogonal test of single factor. Sensory evaluation was used as the main evaluation indexes.The optimum ratio of ingredients was designed as the rose and orange peel ratio of 4:1, 8%of sugar, 0.2% of the citric acid, 0.1% of the honey. A novel kind of beverage with orange red color, sweet taste and rose and orange fragrance was finally produced.