2.1. Pineapple juice
Fresh natural pineapple pulp (Ananas comosus L., Perola variety)
was purchased from the local market. The juice was prepared by
dissolving 100 g of pulp in 100 mL of potable water and the mixture
was then homogenised by sonication at 376Wcm2 for
10 min in a 500Wultrasonic processor (Unique DES500, São Paulo,
Brazil) with a 1.3 cm probe tip. Samples were processed at a
constant ultrasonic frequency of 19 kHz.