Agglomeration process of rice protein concentrate using glucomannan as binder: In-line monitoring of particle size

[Display omitted] •Fluid bed agglomeration of rice protein powder was successfully performed.•Glucomannan can be used as a very special binder for application in agglomeration processes.•In-line particle size measurement (SFV probe) meets the off-line values (Mastersizer).•In-line particle size distribution could be monitored and provided valuable insight into the behavior of the process.•The agglomeration process improved flowability and wettability of the rice protein powder. Rice protein has raised interest from food industry due to its singular nutritional value and nutraceutical properties. However, rice protein concentrate powder presents fine particles with moderate flowability and low wettability, limiting its use. The production of large and porous granules with both high wettability and flowability can be performed by agglomeration process. In this work, the fluid bed agglomeration using konjac glucomannan as binder agent was investigated as a potential method to improve the quality attributes of the RPC powder. The influence of binder concentration and binder feed rate on particle size and quality of the product was evaluated. In-line particle size was monitored by a spatial filter velocimetry probe. Agglomeration was successfully performed in a fluid bed, resulting in large granules with low moisture content, short wetting time and improvement of the flowability. In-line particle size data allowed a better understanding of the particles growth, which was influenced by the binder concentration and binder feed rate. The best operating condition was obtained using low binder concentration and low binder feed rate, since this condition provided an instant powder with very good flowability at the highest yield.