Discrimination of Bottled Mineral Waters using Dip-Type Colorimetric Paper-based Sensor array and Pattern Recognition Methods

Mineral water is natural water that originated from an underground water table, a well, or a natural spring and is microbiologically intact [1]. In this sense, Bottled mineral water has a specific and consistent chemical composition that is determined by the local geology and hydrology [2].moreover, the revenue of the bottled mineral water industry will be USD 342.40 billion in 2023, and it is expected to grow at a compound annual growth rate (CAGR) of 5.24% [3]. Consequently, the discrimination of original bottled mineral water from adulteration (filled with Tap water) is an important issue. In this work, we have developed a Dip-Type colorimetric paper-based sensor array with three organic dyes (Bromothymol Blue, Bromophenol Blue, and Methyl Red) using chemometrics’ pattern recognition methods (PCA and LDA) for discrimination of original bottled mineral waters from adulterated ones based on differences in ion variety and ion quantity. Almost 40 brands of mineral water and 26 Tap water from different regions of Shiraz and other cities were analyzed by this sensor. Moreover, these experiments were performed in two steps to check the period effect on water. This sensor array was able to discriminate these two water types from each other with an accuracy of 92 %.