Siti Nadjiha Mohd Rozali

Doctor of Philosophy, (Chemical and Process Engineering)
Study Completed: 2019
College of Sciences

Citation

Thesis Title
Atomization of fruit juice with fibres as drying aid: Nozzle

Read article at Massey Research Online: MRO icon

Spray drying fruit juices to convert them from liquid to powder is desirable as the powders are easier to handle, especially for storage and transportation. Commercially, maltodextrin is added to the juices as a drying aid to increase the efficiency of the spray drying process. Ms Siti trialled an alternative drying aid, which was pomace fibres. The main attraction of this drying aid was that the pomace fibres were originally derived from the fruits themselves, which ensured the clean labelling of the final juice products. Ms Siti explored the rheology (the branch of physics that deals with the deformation and flow matter, especially the non-Newtonian flow of liquids) of juice-fibre suspensions inside a nozzle and found that the shear and extensional properties of the juice-fibre suspensions were the limiting factors affecting the atomization and spray drying process. She concluded that a two-fluid nozzle system, operating at high atomizing air velocity, was required to successfully atomize and spray dry the juice-fibre suspensions converting them from liquid to powder.

Supervisors
Professor Tony Paterson
Dr Lee Huffman
Professor Jim Jones
Dr Jason Hindmarsh