Preparation And Optimization Of Soybean Lecithin-mint Essential Oil Emulsion And Its Application In Blueberry Juice

Soybean phospholipid is mainly produced from soybean wool oil.Soybean lecithin,as the highest component of soybean phospholipid,has the advantages of low price,wide source and rich nutrition of natural phospholipid,and has been widely used in medical,chemical,food and other industries.Peppermint essential oil has a unique aroma and refreshing characteristics,in the food industry is often used as a beverage seasoning.However,because of its volatile properties,soybean lecithin can be used as emulsifier to embed it and form a relatively stable O/W emulsion.Blueberry juice is one of the product directions of deep processing of blueberry.It has strong antioxidant activity and has certain health care effects in improving vision,protecting cardiovascular health and improving immunity.Combining soybean lecithin with peppermint essential oil and then adding it to blueberry juice to make a drink with unique flavor can make people enjoy delicious food and get health benefits at the same time,and also provide some ideas for developing drinks that give full play to the function of peppermint essential oil.(1)In this experiment,soybean lecithin was used as emulsifier and peppermint essential oil was used as oil phase to prepare O/W emulsion.First,the single factor test was set to determine the general range of various process parameters.Then,through the process optimization test,the state of all the samples under different process conditions was observed during the test period,and several soybean phospholipid-peppermint essential oil emulsion samples in the best state were selected by comparing with each other.Finally,the particle size,stability index,shear viscosity and Zeta potential values were measured respectively and compared with each other.In order to select the best preparation technology of soybean lecithin-peppermint essential oil emulsion.The preparation process was as follows: the concentration of soybean lecithin was 7 %,the concentration of peppermint essential oil was1 %,the homogenizing speed was 6000 r/min,the homogenizing time was 1 min.Soybean lecithin-peppermint essential oil emulsion prepared under this process condition did not show any unstable phenomena such as precipitation,flocculation,water out during the 21 d test period,and can show light yellow color like soybean.(2)In this experiment,the best soybean lecithin-peppermint essential oil emulsion obtained after optimization process was added to blueberry juice,in order to obtain a stable,functional and special flavor of the new drink.Based on the appearance,fragrance and taste,the optimal amount of soybean lecithin-peppermint essential oil emulsion was about 1%.Then the sample was prepared by reducing the gradient,and the stability index and sensory evaluation score were measured respectively.Finally,the optimal emulsion addition process of 1% was determined.The thermal stability test results showed that under the process conditions,after pasteurization at 85 ℃,15 min,standing at 25 ℃,adding soybean lecithinpeppermint essential oil emulsion blueberry juice has better stability and comfortable flavor.(3)The flavor characteristics of blueberry juice,soybean lecithin-peppermint essential oil emulsion,and blueberry juice with added soybean lecithin-peppermint essential oil emulsion were analyzed by electronic tongue,electronic nose and GC-IMS,and compared with each other.It was concluded that soybean lecithin-peppermint essential oil emulsion and blueberry juice had unique and significant flavor.And adding appropriate amount of emulsion to blueberry juice can enrich the flavor of blueberry juice.As can be seen from the above results,soybean lecithin-peppermint essential oil emulsion was prepared under the conditions of soybean lecithin concentration of 7%,peppermint essential oil concentration of 1%,homogenizing rotation speed of 6000 r/min,homogenizing time of 1 min,and was added into blueberry juice according to the mass ratio of 1%.After pasteurization at 85 ℃ and 15 min,the blueberry juice with soybean lecithinpeppermint essential oil emulsion has good flavor and stability,which has certain reference value for the application of soybean lecithin-peppermint essential oil emulsion in food.