Utilization of phenolic compounds extracted from different agricultural wastes through various encapsulation methods

Çilek Tatar, Betül
The main objective of this dissertation was to encapsulate the phenolic compounds extracted from strawberry pomace and olive leaf waste with different coating materials (maltodextrin, gum Arabic, chickpea flour and lentil flour) by using various techniques namely, high-speed homogenization (HSH), high-pressure homogenization (HPH), primary and double emulsion methods (PE and DE). This study was mainly divided into three parts. In the first part of the study, phenolic compounds extracted from strawberry pomace were encapsulated by using different concentrations of maltodextrin and gum arabic mixture. HPH caused to have higher efficiencies (85.99-91.32%) than HSH (81.88-88.15%). Besides, addition of Gum Arabic to maltodextrin increased efficiency. In the second part of the study, another source obtained from olive leaf waste: olive leaf extract (OLE) was encapsulated by using HSH and HPH with lentil and chickpea flours. Efficiencies after HPH treatments (81.87-85.09%) were higher than those after HSH treatment (80.78-80.26%). In the third part, encapsulation of OLE through emulsification methods showed that DE (95.45%) was a better encapsulation technique than PE (72.05%) and entrapment techniques (80.26-91.32%). DE with chickpea flour was found to have higher storage stability and lower release rate than DE with lentil flour. Encapsulated OLE was found to be more heat stable than uncoated OLE during baking. Besides, encapsulation prevented the release of the phenolic compounds in simulated gastric fluid. Release of phenolic compounds in intestinal fluid were found to be higher than the gastric fluid. As a result, DE was found to be the most efficient encapsulation method.


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Citation Formats
B. Çilek Tatar, “Utilization of phenolic compounds extracted from different agricultural wastes through various encapsulation methods,” Ph.D. - Doctoral Program, Middle East Technical University, 2018.