Effects of concentration methods on the characteristics of spray-dried black soybean cooking water

Abstract

Legume cooking water (CW) is a food by-product with the potential of becoming a plant-based egg white replacement; however, limited research has been performed on processes to propel its industrialisation. Consequently, this study assessed the impact of concentration methods (thin-film evaporation; cryoconcentration [CC]; and stove-top boiling [BL]) on the composition and characteristics of spray-dried CW powders. CW was concentrated from 6.8 to 22 degrees Brix. Subsequent analyses showed that the powder characteristics were an outcome of their particle size and composition. CC powders with 18.56 +/- 0.85% protein and D-50 = 0.14 +/- 0.01 mu m presented the lowest-performing functionality. Conversely, BL powders (25.13 +/- 0.50% protein and D-50 = 3.70 +/- 0.47 mu m) displayed enhanced emulsification and foaming. Hence, the properties of CW improved with thermal concentration. These results lay the ground for selecting and optimising a concentration procedure aiming to industrialise the production of CW.