Processing of whey protein-pectin complexes: Upscaling from batch lab scale experiments to a continuous technical scale process

Whey protein-pectin complexes can be applied as fat replacers contributing to creaminess, while adding a source of protein and fiber. Production of these complexes was previously conducted via thermomechanical treatment (90 degrees C, 675 s-1, 19.5 min) on lab scale in small batches (-130 mL). To apply these fat replacers in food products a continuous large scale process at a scraped surface heat exchanger (90 degrees C, 675 s-1) at a throughput of 130 Lxh-1 was established. Process stable whey protein-pectin complexes were achieved, whereas broader complex size distributions were obtained in technical scale process due to differences in residence times and temperature profiles. However, the influence of representative shear rate on complex size could be predicted for technical scale application by pre-experiments on lab scale. In both scales particle size decreased with increasing representative shear rate from 105 to 675 s-1 making it possible to tailor complex size.