Sebastian Linnenkugel

Doctor of Philosophy
Study Completed: 2019
College of Sciences


Thesis Title
Prediction of the glass transition temperature of fruit juice powders

Read article at Massey Research Online: MRO icon

Fruits and fruit juices are a common part of our daily diet and a great source of various natural vitamins, minerals, fibres and phytochemicals. Fresh fruit juices only have a limited shelf life. By reducing the juices to a powdered form the juices can be made stable. However, fruit juices are rich in fruit sugars and organic acids, which makes them difficult to dry. Their low glass transition temperatures lead to stickiness problems during drying. In this work a new method of predicting the glass transition temperature of low molecular weight mixtures of carbohydrates was developed on the basis of their chemical composition. This approach was validated for fruit juice powders and mixtures, including high molecular weight components that are often used as drying aids of these mixtures. The ability to predict glass transition temperatures enables the optimization of powder formulations and drying operations.

Professor Tony Paterson
Dr Lee Huffman
Professor John Bronlund