The effects of adding maltdextrin and limited starch enzyme hydrolyzation on spray-dried instant millet powders

In this paper,instant millet powders were produced by spray drying using two methods,adding maltdextrins(MD) and limiting starch enzyme hydrolyzation. The effects of the two methods on the glass transition temperature,recovery rate,moisture content,water activity,bulk density,caking capacity and microstructure of the instant millet powders were studied. The results showed that,relatively lower DE value,higher addition amount of MD and lower degree of starch hydrolysis would result in a higher recovery rate,glass transition temperature and buck density,a lower moisture content,water activity and caking capacity of instant millet powders. When MD was used as drying carrier,DE8 had a better spray drying effect than DE20. Under the condition of same DE value of feeding solutions,properties of the instant millet powders produced by limited starch enzyme hydrolyzation was superior to the powders produced with MD while the recovery rate was lower.In addition,the microstructure of the particles was also influenced by their various producing methods.