Unveiling low-abundance ACE inhibitory peptides in not-from-concentrate orange juice processed by high-pressure processing and pasteurization

Studies on endogenous bioactive peptides in fruit juice, especially concerning the effects of processing methods on peptides, are still lacking. We developed a pseudotargeted method to analyze 150 novel peptides in fruit juice, detecting more peptides at lower abundance than untargeted methods. Among these, 78 angiotensin converting enzyme (ACE) inhibitory peptides were predicted, with 65 identified across orange juice processed by different processing methods. In high-pressure processing (HPP) juice, abundance of cluster 2 containing 61 peptides increased with pressure, peaking at 550 MPa, while abundance of cluster 1 containing 4 peptides peaked at 250 MPa. In pasteurized juice, abundance of cluster 3 containing 13 peptides increased with temperature, peaking at 95°C, while abundance of cluster 1 and 2 containing 52 peptides peaked at 80°C. HPP juice treated at 550 MPa showed a larger area under ACE inhibition activity curve, indicating higher bioactivity compared to pasteurized juice. This study offers insights into how processing affects low-abundance bioactive peptides in juice, paving the way for bioactivity enhancement of fruit-based products.