The development of the rosa rugosa syrup and its antioxidant and bacteriostatic activity

Rosa rugosa was used to produce rose syrup.On the basis of single factor experiment,using materialliquid ratio,extraction time and extraction times as experimental factor,the optimum process parameters were determined by L_9(3~4) orthogonal experiment.Scavenging effects of 2,2'-Azino-bis-( 3-ethylbenzothiazoline-6-sulfonic acid) diammonium( ABTS) radicals of rose syrup was investigated to study its anti- oxidation activity in vitro,and filter- paper method was used to study the bacteriostatic activity. The results showed that the optimum process parameters of rose syrup was determined as follows: material- liquid ratio 1 ∶ 40,extraction time 2 h,extraction times 4,white granulated sugar 45%,citric acid 0.15%. Under this condition,the rose syrup tasted moderate sour and sweet with rose aroma and fresh palate,the DE was 14.94%,moisture was 54.27%,relative sweetness was 4,viscosity was 500 m Pa·s,p H was 3.43,flavonoids content was 1.95 g / L and density was1.15 g / m L. It also had stronger antioxidant in vitro and bacteriostatic activity: the half inhibitory concentration( IC_(50))on ABTS~+· was 186.1 μL/L,and the rose syrup had good antibacterial activity on Staphylococcus aureus and Escherichia coli,the diameters of antibacterial circle were( 1.37 ± 0.09) cm and( 1.67 ± 0.14) cm.