Here are some steps and suggestions to address the issue:

Homogenization of the Mixture

• Pre-homogenization: The thick texture at the bottom might be due to curd aggregation. To ensure a uniform mixture before spray drying, you can homogenize the fermented soymilk at high pressure (e.g., 100–200 MPa). This will help break down the curd particles into smaller sizes, reducing thickness.
• Sonication: Alternatively, ultrasonication can help break up the curd particles, making the mixture more fluid.

Adjusting the Solids Content

• Dilution: The ratio of 1:10 (soymilk to water) sounds reasonable, but if the product still thickens, you might want to dilute it further to reduce the viscosity. Check the total solids content (targeting around 20% for better spray drying).
• Enzymatic Treatment: Adding proteolytic enzymes (like protease) can help reduce the thickness by breaking down the proteins causing curd formation.

Heating and Stabilizing the Suspension

• Thermal Treatment: Heating the FSM at around 85–90°C for a few minutes before homogenization can help to denature proteins and stabilize the suspension.
• Stabilizers: You can add food-grade stabilizers like lecithin, gum arabic, or maltodextrin to prevent curdling and improve flow properties during spray drying.

Spray Drying Conditions

• Atomization: Use a suitable nozzle type (e.g., rotary atomizer) to prevent clogging, which is common when drying thick mixtures.
• Inlet/Outlet Temperature: Adjust the inlet (e.g., 180–200°C) and outlet temperature (e.g., 80–90°C) depending on the moisture content and heat sensitivity of the soyproteins.

Post-Drying Considerations

• Powder Reconstitution: After spray drying, ensure the powder has good reconstitution properties in water. If curds still form after rehydration, additional process optimization may be needed (e.g., further reduction in solid content).

Dear Mr Deribe Mengistu, Thank you for the detailed answers and guide man, i really appreciate it. The next batch will be done in a few weeks so it will be i while until i update again. Thanks a lot !