PhD student (Food Science) at Stellenbosch University, Graduation date: December 2020


  Study leaders: Professor Elizabeth (Lizette) Joubert; Magdalena (Nina) Muller & Dr Erika Moelich


"I am developing a sensory toolbox to evaluate and communicate honeybush sensory quality."

Tea for the senses

In my research, I focus on developing Qquest, a sensory toolbox for quality control of honeybush tea. This toolbox will include a revised sensory lexicon for honeybush, a scorecard and validated rapid method for assessment of sensory quality. The revised lexicon includes universally available and stable chemical-based reference standards that can be used by researchers, processors, and marketers alike. This research built on a broader research programme of the ARC Infruitec-Nietvoorbij and Stellenbosch University (SU) focussing on the development of a set of sensory tools to define, communicate and evaluate the sensory characteristics of honeybush. These tools will be used to train role players in the industry in aromas associated with high and poor quality tea. The aim is to ensure that honeybush tea of a consistent quality reaches the consumer.

Why this matters

Currently, no standardised sensory language is used for honeybush. Commercial honeybush processors, packers, blenders and marketers all use different ways to evaluate and communicate about sensory quality of tea products. South African government regulations also do not specify sensory standards for honeybush. Tea of variable quality is, therefore, released on the market. Such quality differences could be detrimental to the industry. It is important to create a single standardised set of measures to evaluate the sensory aspects of honeybush tea products. Sensory characteristics are closely linked to the quality of honeybush tea. This toolbox will, therefore, help processors, blenders, packers and marketers negotiate the price of their products. Should their products be of good quality, according to the developed sensory quality standard, determined by the developed sensory quality assessment method, this would aid price negotiation with buyers.

BRIGITTE_DU_PREEZ-small.jpgAbout the student

From a young age, Du Preez was fascinated by the science of aromas and flavours. She completed her BSc degree in food science at Stellenbosch University (SU) in 2002. After working as a research and development technologist and trainee flavourist at an international flavour house, Du Preez returned to the academic world. She participated in a research project on the value-addition of herbal teas at the ARC Infruitec-Nietvoorbij (Post-harvest and Wine Technology Division). Du Preez completed her MSc degree in food science (cum laude) at SU in 2014. Du Preez is currently a doctoral student at SU. She wants to develop and apply her skills to support the emerging honeybush industry.

Brigitte du Preez, a doctoral student at the Department of Food Science at Stellenbosch University, is developing a quality grading system for honeybush to define and evaluate its sensory characteristics.