This book provides new research on fruit juices. Chapter One focuses reports on the validation of an analytical method for the simultaneous determination of citric, malic and lactic acids in fermented passion fruit. Chapter Two analyses citrus pectin as a prebiotic in beverages containing Lactobacillus rhamnosus ATCC 7469. Chapter Three provides a critical review of fruit juices as a nutrient-dense food for health enhancement. Chapter Four examines the role of fruit juice or fruit components in general in the prevention of some of the most relevant neurodegenerative diseases.