A concentrated fruit juice powder obtained by a convection current vacuum freeze drying process that includes: selecting and preparing fruits by predetermined quality guideline; extracting fruit juice by inserting the fruits into a screw press juicing apparatus having a precutter and a screw press whose body surface varies non-linearly, which is configured to achieve a maximum extraction efficiency; adding probiotics into the extracted fruit juice; freezing the fruit juice mixed with the probiotics in molds using an individual quick freezer (IQF) to obtain frozen fruit juice blocks; and vacuum freezing the frozen fruit juice blocks using a convection current vacuum freeze drying apparatus.