Effects of Processing and High-Pressure Pasteurization on Quality of Cold-Pressed Vegetable and Fruit Juices and Smoothies

Fruit and vegetable smoothies, without thermal processing, are susceptible to microbial spoilage. Therefore, this study was aimed to investigate the potential of using high-pressure processing technology to prolong the shelf life of smoothies (kale, apple, and pineapple) using high-pressure processing (HPP) with industrial-sized machinery. The smoothie samples were subject to high-pressure processing using an industrial-scale HPP machine with a capacity of 50L. The samples were tested for microbial reduction using pressures of 500 MPa for 3, 5, 7, 10, and 15 minutes, and pressures of 600 MPa for 3, 5, 7, and 10 minutes. The results revealed that the smoothie samples processed using high-pressure technology at 500 MPa for 7 minutes could reduce the tested microorganisms to nondetectable levels. Additionally, this processing condition closely maintained the pH, vitamin C content, and color comparable to the original product without HPP processing. Moreover, the shelf life of the products was extended to 35 days.