title: Effects of Freeze-dried Mulberry on Antioxidant Activities and Fermented Characteristics of Yogurt during Refrigerated Storage.
abstract: This study investigated the effect of added freeze-dried mulberry fruit juice (FDMJ) (1, 3 and 5%) on the antioxidant activity and fermented characteristic of yogurt during refrigerated storage. A decrease in pH of yogurt and increase in acidity was observed during fermentation. The yogurts with FDMJ exhibited faster rate of pH reduction than control. Initial lactic acid bacteria count of yogurt was 6.49-6.94 Log CFU/g and increased above 9 Log CFU/g in control and 1% in FDMJ yogurt for 24 h. The total polyphenol and anthocyanin content of FDMJ yogurt was higher than that of control due to the presence of phytochemical contents in mulberry. Moreover, antioxidant activity such as DPPH and reducing power was highest 5% FDMJ yogurt. During cold storage, pH decreased or remained constant in all yogurts with values ranging from 4.08 to 4.78 units. In sensory evaluation, the score of 1% FDMJ yogurt was ranked higher when compared with other yogurts. It is proposed that mulberry fruit juice powder can be used to improve sensory evaluation and enhance functionality of yogurt.
authors.affiliation: Food Processing Research Center, Korean Food Research Institute, Seongnam 13539, Korea.
authors.forename: Jung-Min
authors.initials: JM
authors.lastname: Sung
authors.affiliation: Food Processing Research Center, Korean Food Research Institute, Seongnam 13539, Korea.
authors.forename: Young-Boong
authors.initials: YB
authors.lastname: Kim
authors.affiliation: Food Processing Research Center, Korean Food Research Institute, Seongnam 13539, Korea.
authors.forename: Jun-Seok
authors.initials: JS
authors.lastname: Kum
authors.affiliation: Food Processing Research Center, Korean Food Research Institute, Seongnam 13539, Korea.
authors.forename: Yun-Sang
authors.initials: YS
authors.lastname: Choi
authors.affiliation: Food Processing Research Center, Korean Food Research Institute, Seongnam 13539, Korea.
authors.forename: Dong-Ho
authors.initials: DH
authors.lastname: Seo
authors.affiliation: Food Processing Research Center, Korean Food Research Institute, Seongnam 13539, Korea.
authors.forename: Hyun-Wook
authors.initials: HW
authors.lastname: Choi
authors.affiliation: Food Processing Research Center, Korean Food Research Institute, Seongnam 13539, Korea.
authors.forename: Jong-Dae
authors.initials: JD
authors.lastname: Park
keywords: antioxidant activity; polyphenol content; sensory evaluation; yogurt; μ dried mulberry