Contact angle and surface energy analysis of soy materials subjected to potassium permanganate and autoclave treatment

- Initial contact angle of soy flour is very low and soy protein isolate, insoluble soy and soy hulls have increasingly higher initial contact angles.
- Soy flour has high polar surface energy fraction which makes them less compatible with non-polar polymers.
- KMnO4 treatment increases the contact angles and decreases the apparent rates of water absorption for most soy products.
- Autoclave treatment shows significant increase of apparent rate of water absorption for soy products with high protein contents.