Anthocyanin composition in grape skin: a comparative analysis of the Moldovan varieties Feteasca Neagra and Rara Neagra

Abstract

This study focuses on the anthocyanin composition of grape skin powder (GSP) derived from two grape varieties native to the Republic of Moldova: FeteascA NeagrA and RarA NeagrA.

The analysis aimed to quantify and compare the anthocyanin profiles of these grape skins, emphasizing their potential applications in functional foods and nutraceuticals due to their bioactive properties. Among the ten analyzed anthocyanins, malvidin-3-glucoside emerged as the predominant compound in both grape varieties, constituting 67.63% of total anthocyanins in FeteascA NeagrA and 63.84% in RarA NeagrA. This significant presence highlights the role of this compound in influencing the color and antioxidative properties of the grape skins. FeteascA NeagrA grape skin powder demonstrated higher concentrations of several anthocyanins, including petunidin-3-glucoside (12.06%), delphinidin-3-glucoside, malvidol diglucoside, and peonidin-3-

glucoside, suggesting a richer anthocyanin profile that may contribute to stronger antioxidant potential and desirable color attributes in food applications. On the other hand, RarA NeagrA displayed higher levels of compounds such as peonidin-3-acetylglucoside, cyanidin-3-glucoside, malvidin-3-acetylglucoside, peonidin-3-coumarylglucoside, and malvidin-3-coumarylglucoside.

These differences indicate unique anthocyanin compositions that can impart distinct sensory

attributes and functional benefits, depending on their application. The abundance of specific anthocyanins in each variety underscores the potential for selective use based on desired product characteristics, such as color intensity and health benefits. Similar findings have been reported in the literature, where malvidin-3-O-glucoside is often the dominant anthocyanin in red grape varieties, highlighting its significance in the pigmentation and potential health benefits of grape-derived products. The diverse anthocyanin profile in these grape varieties suggests their promising use in developing functional foods that capitalize on their antioxidant properties while promoting the principles of a circular economy and sustainability by utilizing grape by-products as valuable ingredients.