Profile and levels of bioactive amines in orange juice and orange soft drink

The levels of bioactive amines, pH, soluble solids, acidity, specific gravity, and total sugars were determined in different brands of orange products. Nine amines were detected in orange juice at mean total levels of 53.5 mg l−1. There were significant differences, among orange juice brands, in the levels of spermidine, synephrine, spermine, octopamine, pH and total acidity. Five amines were detected in soft drinks with mean total levels of 3.85 mg l−1. There were significant differences, among orange soft drink brands, in the levels of most amines and the physicochemical characteristics. The predominant amine was putrescine, followed by synephrine and spermidine, in both orange juices and soft drinks. The levels of these amines in the soft drink varied from 5.0% to 7.6% of the mean levels in orange juice, suggesting that less than 10% of orange juice could have been used in the soft drink.