Comparative Evaluation of Anthocyanin, Phenolic Compound, and Flavonoid Contents in the Peel and Flesh of Differently Colored Potato Tubers

Abstract

Background and Objective. Pigmented-flesh potatoes are a valuable source of biologically active compounds, including anthocyanins, phenolic compounds, and flavonoids, which exhibit pronounced antioxidant activity. The content of these compounds may vary considerably depending on the flesh color and the anatomical part of the tuber. The objective of this study was to conduct a comparative biochemical analysis of the peel and flesh of potato tubers with different flesh colors in terms of their anthocyanin, phenolic compound, and flavonoid contents.

            Materials and Methods. Potato tubers of Kazakhstani and foreign cultivars with different flesh colors were used as the study material. The peel and flesh were analyzed separately. Total anthocyanin, total phenolic compound, and total flavonoid contents were determined using spectrophotometric methods. The obtained data were statistically analyzed using Microsoft Excel.

            Results. The results demonstrated that, regardless of flesh color, the potato peel contained significantly higher levels of anthocyanins, phenolic compounds, and flavonoids than the flesh. The highest anthocyanin content was recorded in breeding line 17-223-10, reaching 233.1 ± 2.17 mg/100 g dry weight in the peel. The highest total phenolic content was observed in the cultivar Olyushka (21.75 ± 3.08 mg/g dry weight), whereas the highest flavonoid contents were detected in the cultivars Olyushka (28.52 ± 0.28 mg/g dry weight) and Kiru (28.20 ± 0.13 mg/g dry weight). High anthocyanin levels were also found in the cultivars Xisen 8 and Red Rose. In all investigated genotypes, the concentrations of biologically active compounds were significantly higher in the peel than in the flesh.

            Conclusion. The findings indicate that the peel of pigmented-flesh potato tubers is the richest source of anthocyanins, phenolic compounds, and flavonoids. The breeding line 17-223-10 and the cultivars Olyushka, Xisen 8, and Red Rose showed the greatest potential in terms of antioxidant compound content. These results highlight the potential for the integrated utilization of both the peel and flesh of colored potatoes in the food industry, particularly in the production of functional foods and natural antioxidant ingredients.