Soy sauce powder is spray dried from liquid soy sauce and mixed with other auxiliary ingredients. Here is a formula of soy sauce powder:
Natural fermented soy sauce 45%-50%
Salt, sugar and MSG 7%-9%
Yeast extract, guanylic acid, inosinic acid, spices, etc. 1%-3%
To produce good quality soy sauce powder, you need use good quality materials. The liquid soy sauce need to be natural fermented soy sauce and smells good, the color of the liquid soy sauce should be red and brown, and taste should be umami, the concentration of amino acid should be above 0.8g/100mg. The filler used in soy sauce powder should be free flowing, no bad smell and taste, many manufacturers would use malt dextrin as filler. Yeast extract can obviously prove the umami flavor of soy sauce powder, according to the quality, it can be added properly. The proportion of guanylic acid and inosinic acid is 1:1 and then blended with MSG as the proportion of 5:95.