Reverse osmosis is a promising alternative for the concentration of fruit juice, but the potential is limited due to a lack of studies in pilot and industry development. Moreover, there is scarce information on the development of the reverse osmosis system in terms of design and fabrication at the lab scale. Therefore, this book discusses the application of a high-pressure reverse osmosis system aimed at fruit juice concentration. Optimization techniques using Response Surface Methodology (RSM) and quality analysis of the pineapple juice are also highlighted.