The extraction, identification, and encapsulation of phenolic compounds from Prunus domestica subsp. institia towards their incorporation into a functional milk product : a thesis presented in partial fulfilment of the requirements for the degree of Master of Food Technology at Massey University, Manawatū, New Zealand. EMBARGOED until 29 July 2024.

Embargoed until 29 July 2024Damson plums are rich in bioactive compounds such as polyphenols, flavonoids, and anthocyanins, which are potent antioxidants with proven health-promoting properties. However, to date, there is no systematic publication/report about the type and concentration of various bioactive compounds in damson plums or using this type of plum as a food ingredient in the food industry. This study aimed to: 1) optimise the extraction of the bioactive compounds from Prunus domestica subsp. Institia (damson plums) grown in New Zealand using efficient extraction methods such as accelerated solvent extraction (ASE), ultrasound-assisted extraction (UAE), enzyme-assisted extraction (EAE), and their combined (E+UAE) extraction, in water or ethanol as the solvents; 2) analyse the total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC), and total antioxidant activities of the damson plums extract; 3) encapsulate the above-mentioned extract to protect the bioefficacy of its phenolic compounds; 4) compare the physical and chemical stabilities of the manufactured encapsulated ingredient in freeze-dried or liquid form during storage; and 5) assess the behaviour of the encapsulated plum extract after its incorporation into a functional milk product. Fresh New Zealand damson plums were freeze-dried and ground into a powder and extracted with different methods explained above. The freeze-dried damson plum powder (FDDPP) was then encapsulated in liposomes made of soy lecithin granules using high-shear homogenisation and/or microfluidisation. The encapsulation efficiency (EE) was assessed by the determination of various phenolic compounds using high-performance liquid chromatography (HPLC) before and after the application of Sephadex filtration to separate free phenolics and encapsulated phenolics. Finally, the encapsulants containing damson plum powder were incorporated into milk (whole/full-fat) as a functional beverage, and the effect on the physiochemical properties of the milk product was assessed.—Shortened abstrac