Identification of white scale formation in pineapple juice concentrate

Abstract

© 2019 Elsevier B.V. White scale formation in pineapple juice concentrate product has caused the loss of export value. Therefore, it is very interesting to identify chemical components of white scale formation and investigate the root cause of white scale formation for prediction and finding the method to prevent this problem. White scale was separated from pineapple juice concentrate and analyzed by using inductively coupled plasma mass spectrometry (ICP-MS), microwave plasma atomic emission spectrometry (MP-AES), powder X-ray diffraction analysis (XRD), and Fourier transform infrared spectrometry (FTIR). From the analyses, white scale contains organic component which is cellulose and inorganic compound which is calcium carbonate (CaCO 3 )in calcite form. Furthermore, the cause of white scale formation was investigated by considering pH and acidity of pineapple juice (intermediate product). With the acidity lower than 0.65% and pH higher than 3.80, white scale might form in pineapple juice concentrate (final product), suggesting that the industry can predict and prevent this problem by controlling pH and acidity level.