Correlating the natural color of tropical fruit juice with its pH

• Published in: Color research and application Vol. 46; no. 2; pp. 467 - 476
• Main Authors: Muhammad Zahir, Siti A. D., Yahaya, Ommi K. M., Omar, Ahmad F.
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.04.2021; Wiley Subscription Services, Inc
• Subjects: carambola; CIELAB; Color; color analysis; Fruit juices; Fruits; Juices; mango; Mangoes; Pigments; Quality management; Red pigments; Regression analysis; RGB color model; Ripening
• ISSN: 0361-2317; 1520-6378
• DOI: 10.1002/col.22575

Color analysis is a critical approach used to analyze the quality properties of fruits, particularly in tracing the ripening stage through the peel color of the fruits. In this study, the color features of natural and untreated tropical fruit juice images (ie, B10 Averrhoa carambola L. and Sala mango) were correlated with the pH of the juice samples. The CIELAB color characteristics of the fruits showed that the mango juice had darker features than the carambola juice. The cause may be due to the higher soluble solid content and denser yellow and red pigments in the mango juice. For carambola juice, multiple linear regression (MLR) performed on red‐blue (RB) components generated the best prediction of pH with the highest coefficient of determination and lowest root mean square of error. For mango juice, MLR performed on normalized red‐green‐blue (RGB) components generated the best prediction of pH.