Optimization Of Rhodiola Active Ingredient Extraction Technology And Development Of Yogurt Products

Rhodiola plants have strong anti-hypoxia,anti-oxidation,anti-fatigue,anti-inflammatory,anti-viral,anti-cancer,anti-tumor,anti-radiation effects.There is a good development trend in medicine,cosmetics,functional products,health products and so on.At present,the extraction technology of salidroside in Rhodiola adopts more complicated extraction process,and the extraction rate is not high.Optimization of a simple and efficient extraction technology provides technical support for the effective application of Rhodiola plants.In addition,there is little research on Rhodiola yoghurt at home and abroad,and there are more technical and safety issues to be considered.For example,fermenting Rhodiola yoghurt with different strains may cause the water retention,acidity,Viscosity,which in turn affects the texture characteristics and drinking taste of Rhodiola yoghurt,may also cause the nutritional value of Rhodiola.In view of the above problems,this paper optimizes the extraction technology of salidroside,screens the starter of Rhodiola,and optimizes the fermentation process of Rhodiola,which has certain significance for improving the development and utilization of Rhodiola.The specific results are as follows: 1.Optimization of extraction technology of salidrosideBy comparing the extraction effects of salidroside with three extraction techniques including ultrasonic-assisted ethanol extraction,reflux extraction,and ethanol extraction,the optimal extraction method was determined to be a combination of extraction and ultrasound.Taking the content of salidroside as an index,the single factor method was used to explore the influence of extraction conditions such as ultrasonic time,ethanol concentration,material-liquid ratio and extraction temperature on the extraction effect of salidroside.Through the optimization and verification of response surface test,the optimal extraction conditions of salidroside were determined as follows: ethanol concentration 60 %,extraction temperature 30?,ultrasonic time 2h,material-liquid ratio 1:80(g/m L).Under this condition,the content of salidroside in the extract is 2.35 mg/g.2.Screening of Rhodiola yoghurt starter strainsComparison and screening of four groups of starter strains S 4.30(Streptococcus thermophilus + Lactobacillus bulgaricus),Lb S 22.70(Lactobacillus acidophilus),LC 58(Lactobacillus casei),Lb S 22.11(Lactobacillus plantarum),through An analysis of the curd time,acidity,and sensory scores of yogurt during fermentation revealed that the optimal starter strain was a combination of S 4.30 and LC 58;S 4.30 and LC 58 were mixed in different proportions to make a mixed starter strain pair After fermenting the yoghurt,combined with the total number of lactic acid bacteria,acidity,p H,water holding capacity,viscosity and sensory evaluation results,the optimal starter strain and the ratio were determined to be S 4.30:LC 58=1:3.3.Study on fermentation technology of RhodiolaThe Rhodiola yoghurt stabilizer was screened by a single factor combined with response surface method,and the optimal formulation and ratio of the stabilizer were determined as follows: single fatty acid glyceride addition amount: gelatin addition amount: pectin addition amount=4:3:3.Under these conditions,the effects of Rhodiola extract,fermentation temperature,starter inoculum and white granulated sugar on the fermentation efficiency of Rhodiola were studied.The results showed that the best fermentation technology of Rhodiola was: the addition of Rhodiola extract was 4%,the addition of white granulated sugar was 6%,the inoculation amount of starter was 3.7%,and the fermentation temperature was 41 ?.The recovery rate of salidroside in Rhodiola yoghurt prepared under the optimal fermentation process is 80%.This paper optimizes the extraction technology of salidroside,the main active ingredient in Rhodiola,and applies the extract to the development of yogurt products.The strains of Rhodiola starter were screened,and the fermentation conditions of Rhodiola were studied,which provided a theoretical basis for the effective utilization of Rhodiola resources and the research and development of yogurt.