Use of Smartphone and Image Analysis in the Quantification of Vitamin C in Golden Berry (Physalis peruviana L.) Juice

Conventional methods used to quantify vitamin C require expensive equipment; however, the image analysis method has proven to be effective in quantifying various bioactive compounds and could be useful for small industries due to its low cost. In this sense, the objective was to evaluate the use of a Smartphone and image analysis in the quantification of vitamin C in golden berries juice. Calibration curves were elaborated with ascorbic acid standards (2.5-20 mg L-1) and the Folin-Ciocalteu chromophore reagent (10%). Fifteen color parameters (analytical responses) were obtained from images obtained with a Smartphone and the ImageJ program of the colored samples using four backlight colors, to which a principal component analysis was applied using the integrated development environment for R, RStudio. Subsequently, one-way ANOVA and mean comparisons by Tukey's method (α = 0.05) were applied to the best-scoring analytical response's. Ultimately, the quantification of vitamin C in golden berry juice was performed using the image analysis method, which exhibited superior linearity and sensitivity (R2 = 0.9941 and m = 4.91). A comparative assessment was conducted against a spectrophotometric method utilizing the t-Student test for independent samples (α = 0.05), demonstrating no statistically significant difference between the two methods (p > 0.05).