Influence of Selected Factors on Anthocyanin Stability in Colored Potato Extracts

Abstract

Color is considered as an important quality trait of food products. The blue, purple or red colors of several fruits and vegetables are due to the presence of anthocyanins. Scientific evidence suggests that these pigments are health‐promoting compounds and there is some research focused on the development of anthocyanin‐based natural colorants. However, anthocyanins levels can be altered through the action of several factors during food processing and storage. In this study, prevention of degradation of anthocyanins in potato extracts through combining the addition of gallic acid as copigment and the presence or absence of light with different temperatures was investigated. The four studied factors were statistically significant (P ≤ 0.01), but genotype showed the major effect, followed by light, temperature and gallic acid addition. The stability of anthocyanins can be increased throughout the combination of low temperature (T = 4C), absence of light and gallic acid addition (pigment : copigment molar ratio 1:50). Practical Applications Besides having important biological roles, such as antioxidant activity, anti‐inflammatory and anticarcinogenic properties, anthocyanin‐rich plant extracts might have potential as food colorants. In fact, colored potatoes have been suggested to be a great source of anthocyanins and a potential source of natural colorants. The major problem of anthocyanin‐based natural colorants is their instability under nonacidic normal processing and storage conditions. With the aim of preventing the degradation of anthocyanins to colorless phenolics and insoluble brown compounds, there have been several studies conducted through the addition of different additives. In the present study, the stability effect of gallic acid as a copigment was investigated in different conditions, considering two important factors that influence the preservation of anthocyanins (temperature and light) in purple and red‐fleshed potato extracts. Our results contribute to the development of preparation processes of food products and colorants derived from colored potatoes with increased anthocyanin content and color intensity.

Isolation of High Purity Anthocyanin Monomers from Red Cabbage with Recycling Preparative Liquid Chromatography and Their Photostability

“…All tested anthocyanins decomposed rapidly in the simulated solar light irradiation experiments, as shown in Figure 6 C. After 24 h of irradiation, Cy-3-soph-5-Glc and Cy-3(sin)-diGlc-5-Glc decreased to 33% and 44%, respectively, and only a trace level of Cy-3-(glucofer)-diGlc-5-Glc remained after 24 h. These observed results are in agreement with previous reports regarding the photostability of anthocyanins under various conditions [ 31 , 32 ]. Furthermore, the photostability of red cabbage anthocyanin monomers is significantly affected by the number of acylated groups.…”

Natural Pigments: Stabilization Methods of Anthocyanins for Food Applications

“…Various physicochemical parameters influence the stability of anthocyanins, such as pH of the product, light exposure, temperature, and complexation with other compounds in the matrix which may result in the fading or modification of the expected color (Sui and others ; Tierno and Ruiz de Galarreta ). There are reports regarding the use of several compounds (Figure ), such as flavonoids, alkaloids, amino acids, organic acids, nucleotides, polysaccharides, metals, or even other anthocyanins to copigment anthocyanins, all with the purpose of reducing color degradation.…”

Impact of Lignosulfonates on the Thermodynamic and Kinetic Parameters of Malvidin-3-O-glucoside in Aqueous Solutions

“…The low chemical stability of anthocyanins with pH, light, temperature, and exposure to oxygen has been limiting their use in some food matrixes such as colorants. − However, during the last few decades, different strategies have been evaluated to stabilize the red color of anthocyanins, and this includes the use of polymeric compounds (pectins and whey proteins), − gums, cyclodextrins, , phenolic compounds, − metallic ions, and thiol compounds such as glutathione, cysteine, and cysteine derivatives…”