“Biorefining the by-products of plant material processing into valuable functional ingredients by applying various extraction techniques” Doctoral Thesis

Author, institution: Darius Povilaitis, Kaunas University of Technology

Science area, field: Technology Sciences, Chemical Engineering – 05T

The Doctoral Dissertation is available at the library of Kaunas University of Technology (K. Donelaičio St. 20, Kaunas)

Scientific Supervisor: Prof. Dr. Petras Rimantas Venskutonis (Kaunas University of Technology, Technological Sciences, Chemical Engineering – 05T).

Dissertation Defence Board of Chemical Engineering Science Field:

prof. habil. dr. Juozas Vidas Gražulevičius (Kaunas University of Technology, Technological Sciences, Chemical Engineering – 05T)  – chairman,
prof. habil. dr. Gražina Juodeikienė (Kaunas University of Technology, Technological Sciences, Chemical Engineering – 05T)
dr. Paulius Kraujalis (Kaunas University of Technology, Technological Sciences, Chemical Engineering – 05T)
prof. habil. dr. Audrius Sigitas Maruška (Vytautas Magnus University, Physical Sciences, Chemistry – 03P),
dr. Dalija Seglina (Latvia State Institute of Fruit-Growing, Physical Sciences, chemija – 03P).

Annotation:

There is a growing demand for healthy food products, since more and more people are concerned about their health. Consequently, many researchers are searching for new, natural and valuable bioactive compounds. Furthermore, it is crucial to reduce the growing production of industrial waste. Combining novel plant biomass conversion technologies allows to decrease by-product production and develop new promising value-added products and chemicals. This study investigates the valorization of rye and wheat bran and blackcurrant pomace using multistep processes for biorefining the biomass into high value food-grade functional ingredients. Firstly, rye and wheat bran antioxidant activity was evaluated by using pressurized solvent extraction with organic solvents. Then, environmentally friendly supercritical carbon dioxide extraction was optimized using response surface methodology with central composite design for effective isolation of lipophilic fraction. Finally, pressurized liquid extraction and enzyme-assisted extractions were applied to isolate higher polarity substances. Different antioxidant activity assays were applied to determine the best fractions for the value-added ingredient production.