The use of by-products in the preparation of functional products

Nujamee Ngasakul, MSc

Doctoral thesis

Abstract:

Food processing generates substantial volumes of by-products that are frequently discarded despite retaining considerable nutritional and functional value. This dissertation investigates the potential to valorize by-products, such as poppy seed cake, apple pomace, and carrot pomace, for use as functional ingredients in food systems. The thesis focuses on transforming these underutilized materials into functional products while exploring how their incorporation influences the nutritional composition, techno-functional properties, and sensory quality of prototype food products. Additionally, this dissertation is focused on the challenges and opportunities associated with the industrial scale since the utilized by-products are obtained from the Food Technology Center of the Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague. The by-products are examined with emphasis on their sustainable integration into the development of functional foods based on novel colloidal systems, including plant-based ice cream fortified with poppy seed cake, set-type yogurt with the addition of apple pomace, and spreadable bigel incorporated with carrot pomace. Additionally, the basic research on the potential applications of carrot pomace in cosmetic formulations has been provided. The results demonstrate the feasibility of valorizing by-products as a promising natural ingredient alternative to synthetic ingredients, as confirmed by the composition of the materials, which are rich sources of bioactive compounds, dietary fiber, proteins, and micronutrients. Their incorporation into food systems yielded improvements in techno-functional properties and nutritional composition while maintaining acceptable sensory profiles. Furthermore, the study provides preliminary results as basic information for future applications. The findings of this dissertation contribute to knowledge of sustainable development approaches in the food sector and underscore the potential of food by-products for the development of novel foods.

Keywords

Food By-products, Functional products, Colloidal systems, Waste valorization, Sustainable production

Language used: English

Date on which the thesis was submitted / produced: 27. 5. 2026

Thesis defence

• Supervisor: doc. Ing. Iveta Klojdová, Ph.D.
• Reader: Svatopluk Henke, externi, Richardos Nikolaos Salek, externi

Czech University of Life Sciences Prague

Faculty of Agrobiology, Food and Natural Resources

Doctoral programme:
Nutrition and Food