A New Method for the Determination of Potassium Sorbate Combining Fluorescence Spectra Method with PSO-BP Neural...

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Chemometrics

Background:

• Potassium sorbate is a widely used food preservative.
• Accurate determination of potassium sorbate concentration is crucial for food safety and quality control.
• Existing methods for potassium sorbate analysis may have limitations in complex matrices like orange juice.

Purpose of the Study:

• To investigate the fluorescence spectra properties of potassium sorbate in aqueous solution and orange juice.
• To develop a novel, accurate method for determining potassium sorbate concentration in orange juice.
• To evaluate the feasibility of a Particle Swarm Optimization-Back Propagation (PSO-BP) neural network for this application.

Main Methods:

• Characterization of potassium sorbate fluorescence spectra in different solutions.
• Two-dimensional fluorescence spectral analysis to understand intensity-concentration relationships.
• Development and application of a PSO-BP neural network model for concentration prediction.
• Validation of the method using relative error analysis.

Main Results:

• Potassium sorbate exhibits a characteristic fluorescence peak at λ(ex)/λ(em) = 375/490 nm in both aqueous solution and orange juice.
• A complex, non-linear relationship exists between fluorescence intensity and potassium sorbate concentration.
• The PSO-BP neural network achieved high accuracy, with relative errors of 1.83% and 1.53% in predicted concentrations.
• The method demonstrated feasibility for measuring potassium sorbate in the range of 0.1-2.0 g·L⁻¹.

Conclusions:

• The characteristic fluorescence peak of potassium sorbate is identifiable across different matrices.
• A non-linear model is necessary for accurate concentration determination due to complex spectral responses.
• The PSO-BP neural network offers a robust and accurate approach for quantifying potassium sorbate in orange juice.
• This method provides a valuable tool for food quality control and preservative monitoring.