Preparation,properties Andapplication Of Stearate Rice Starch By Drum Dryer

Stearate rice starch(SRS) is prepared by drum drier with rice starch as raw material,stearic acid as esterifying agent.Based on it's physical and chemical properties,it was applied in low-fat mayonnaise as fat replacer. At the same time,we studyed the sensory attributes of the low-fat mayonnaise and it's stability during storage.It showed that:SRS can be used in low-fat mayonnaise as fat replacer.Firstly,the process conditions of stearate rice starch prepared by drum drier were studyed.By single factor experiment,we studyed the effect of the steam pressure, drum speed, concentration, addition of stearic acid and HCL on the degree of substitution(DS).According to the results of single factor experiment,orthogonal test L9(34)was designed and the optimum process conditions of stearate rice starch prepared by drum drier were determined:100g rice starch,starch concentration 35%,drum speed 50r/min,steam pressure 0.7MPa,stearic acid 3%,HCL0.116%.Then we studyed the properties of the stearate rice starch such as viscosity,emulsifying ability,freeze-thaw stability, rheology and texture.At the same time,we detected the group?structure ,crystal structure and molecular weight distribution respectively with FTIR ,XRD and HPGFC.It is showed that:-OH of rice starch was linked up with–COOH of stearic acid during reaction, crystal structure was destructed and molecular weight reduced.Stearate rice starch prepared by drum drier has good emulsifying ability,and its'G'and hardness value become smaller as DS is bigger.By comparing with preliminary application of stearate rice starchs with different DS in mayonnaise,we can find that the stearate rice starch with largest DS was more suitable for mayonnaise as fat replacer.Prepare different fat-substitution of mayonnaise with stearate rice starch which has the largest DS as fat replacer and discuss its'rheological and textural properties.At last the fat substitution of low-fat mayonnaise was determined as 40% by sensory evaluation.Lastly,with the full-fat mayonnaise selfdone and low-fat mayonnaise buyed in market as comparison, we investigated the stability of mayonnaise with 40% of oil substitution during storage.By detecting rheological and textural properties,particle size,color, peroxide value and the total plate count of mayonnaise,we can find the good preservativity effect of stearate rice starch as fat replacer on the low-fat mayonnaise.