SPI (soybean protein insolate) is usually extracted from soybean
defatted meal which is from normal hexane solvent extraction
workshop. The used soybean is high quality, cleaned and husked.
This defatted meal is called white flake” in industry. Isolating
soybean protein removes various nonprotein ingredients, retain
protein and make dry basis protein content up to more than 90% (
There are mainly nine steps to produce SPI.
The first step is alkaline water extraction. Water temperature, PH
value and dwell time is very important in this step.
The second step is separating extracted white flakes from solvent
with the help of machines.
The third is acid precipitation with hydrochloric acid.
The fourth is separating whey from stick.
The fifth is adjusting to get multiple different functional protein
The sixth is neutralization with NaOH.
The seventh is heat treatment and stick adjusting.
The eighth is dehydration with spray drying.
The ninth is weighing and packing.
We use intermittent extraction, acid precipitation and continuous
isolating technology. PH value is under manually controlled system.
Besides guaranteeing extraction and acid precipitation effect, it
can make technical process and parameters stable. So the SPI
quality can be stable and consistent.
With double-dip extracting, it can extract good protein in white
flakes fully and effectively.
Energy saving and consumption reducing are always important part in
Sterilizing technics is going to use direct steam sterilization and
flash dehydration cooling. On the one hand, it can kill bacteria in
curd effectively. On the other hand, it can remove beany flavorand
peculiar smell in soybean milk.
It is considered to use enzymolysis technology to produce injected
protein isolate. It can increase product variety.