Study On Preparation Process And Stability Of Barley Emulsion Beverage

Barley is abundant in nutrients and functional substances which are very healthy.Developing barley beverage can make full use of barley, improve the utilization value. Andthe rice bran oil is high in unsaturated fatty acids, has no special smell, adding the rice branoil into barley beverage can not only decrease the intake of trans-fatty acids but also increasethe nutritional value of barley beverage.Barley rice bran oil beverage, mainly made of barley, is a kind of healthy, nutritionalcereal beverage with unique taste. Which was made through roasting, grinding, enzymatic,mixing, homogenization and sterilization.Firstly, the barley was roasted to produce pleasant flavor, the best roast condition was180℃,15min. The microstructure of barley powder starch before and after roasting werestudied through SEM. The main volatile components before and after roasting were analyzedby solid phase micro-extraction and GC-MS techniques. The main volatile components afterroasting were pyrazines and furans compounds.The roasted barley was grinded and subjected to enzymatic treatment to obtain barleyplasm, the optimum water ratio was1:14through study of the utilization of raw material.Enzymatic reaction conditions were optimized through factorial and response surfaceexperiments: enzymatic temperature90℃, enzymatic time70min, enzyme quantity60U/g.The dosage of sugar was determined through sensory evaluation: Sucrose4%. The rice branoil was chosen through stability experiments and sensory evaluation of different vegetableoils.Secondly, the influence of food additives on the stability of beverage was studied. Theemulsifiers’ effect on the ESI, interfacial tension and PDI of barley beverage emulsion werestudied.The result showed ESI and interfacial tension, PDI were negative correlated, PDI andthe interfacial tension was significantly positive correlated; The effect of different thickenerson ESI, viscosity and rheological properties were studied. Then the main emulsioncomponents were studied using the response surface methodology (RSM). Thephysicochemical properties considered as response variables were zeta potential,emulsionstability(ESI), polydispersity index(PDI).The overall optimum region resulted in a desirablebarley beverage emulsion was predicted to be obtained by combined level of0.2%Citrem,0.1%SMS,0.9%rice bran oil,0.07%xanthan gum and0.3%carrageen.Then the effects of homogenization pressure, temperature and times on the partical sizeand SR were studied. The optimum homogenization condition: first homogenization pressure30MPa, second homogenization pressure40MPa, homogenization temperature50℃. Theeffect of different sterilization methods on color, pH, viscosity, partical size and rheological properties were also investigated. The final sterilization condition was121℃,20min.The content of the trans-oleic acid was measured through GC, the barley rice bran oilbeverage fat has0.13%trans-oleic acid,1.63%trans-linoleic acid, while the content of thetrans-oleic acid and trans-linoleic acid in the fat of barley beverage with non-dairy creamerwere7.75%and0.23%. The main volatile components of barley beverage were analyzed bysolid phase micro-extraction and GC-MS techniques. The main volatile components weresmall alcohols and pyrazines compounds.Finally, the storage stability was studied. During the storage period, barley beverage hadcertain change, but it didn’t affect the quality of the beverage, and the particle size, pH andviscosity had no obvious change, Barley rice bran oil beverage was stable during the givenstorage time.