Quantification of organic acids using voltammetric tongues

Area of Science:

• Electroanalytical Chemistry
• Food Science and Technology

Background:

• Electronic tongues (ET) are emerging as powerful tools for food quality analysis, offering an alternative to conventional methods.
• ET systems utilize sensor arrays with cross-sensitivity to simultaneously detect multiple analytes in a sample.

Purpose of the Study:

• To evaluate the efficacy of an electronic tongue (ET) employing pulse voltammetry for quantifying organic acids.
• To assess the performance of various electrodes in detecting ascorbic, citric, and malic acids in simple and binary solutions.

Main Methods:

• An electronic tongue system based on pulse voltammetry was developed.
• Experiments were conducted using simple solutions (SS) and binary solutions (BS) containing specific organic acids.
• The predictive capabilities of different electrodes (Ni, Ag, Ir, Rh, Pt, Cu) were investigated using both positive and negative pulses.

Main Results:

• Nickel (Ni) and Silver (Ag) electrodes showed high significance for ascorbic acid prediction in simple solutions.
• Silver (Ag) and Iridium (Ir) electrodes were most effective for ascorbic acid prediction in binary solutions, with positive pulses being optimal.
• Iridium (Ir), Rhodium (Rh), Platinum (Pt), Silver (Ag), and Copper (Cu) electrodes demonstrated suitability for citric and malic acid prediction in both simple and binary solutions, irrespective of pulse polarity.

Conclusions:

• The study validates the potential of electronic tongues with pulse voltammetry for accurate organic acid quantification in food-related samples.
• Specific electrode-material combinations and pulse polarities can be optimized for the selective detection of different organic acids.