Spray-dried whey protein isolate (WPI) powders were prepared at pilot-scale from solutions without heat (WPIUH), heated (WPIH) or heated with calcium (WPIHCa), which were analysed and compared with a control sample (WPIC). WPIC, WPIUH, WPIH and WPIHCa solutions had whey protein denaturation levels of 0.0, 3.2, 64.4 and 74.4%, respectively. Computerised tomography scanning showed that 52.6, 84.0, 74.5 and 41.9% of WPIC, WPIUH, WPIH and WPIHCa powder particles had diameters of ≤30 µm. WPIHCa and WPIH powders were cohesive, while WPIC and WPIUH powders were easy flowing. Marked differences in microstructure were observed between WPIH and WPIHCa. There were no measured differences in wall friction, bulk density or colour.
Bibliographical noteFunding Information:
This work was supported by the Food Institutional Research Measure (FIRM) project ‘Developing the next generation of high protein spray‐dried dairy powders with enhanced hydration properties’ (DAIRYDRY 15‐F‐679) funded by both the Irish Department of Agriculture, Food and the Marine and the Department of Agriculture, Environment and Rural Affairs in Northern Ireland. The authors would like to acknowledge and thank David Waldron for powder pictures and Agnieszka Furman from Waterford Institute of Technology (Waterford, Ireland) for sample preparation and CT scanning.
© 2021 The Authors. International Journal of Dairy Technology published by John Wiley & Sons Ltd on behalf of Society of Dairy Technology
- Whey protein
- Physical properties