Ms Kleih successfully defended her doctoral thesis titled „Fresh fruit and vegetable branding: Investigating consumer behavior with visual and mixed methods“ on July 12th, 2022 at Hochschule Geisenheim University.
The cooperative Doctorate was supervised by Prof. Dr. Kai Sparke, Department of Fresh Produce Logistics, Hochschule Geisenheim University and Prof. Dr. Rainer Kühl, Faculty 09, Department of Business Administration of the Agricultural and Food Sector, Justus-Liebig-University Giessen. 
The doctoral thesis was jointly evaluated together with Prof. Dr. Jasmin Godemann-Herzig, Faculty 09, Department of Consumer Research, Communication and Food Sociology, Justus-Liebig-University Giessen.