Effect of SO₂ Treatment on Stability of Anthocyanin Pigments in Berries

Anthocyanins are natural pigments widely distributed in nature. Anthocyanin color molecules are a subclass of flavonoids. They are responsible for the reds, purples and blues in many flowers, fruits and vegetables. Fruits and berries are the most sample sources of anthocyanins in nature. Berries and fruits are an important part of the Finnish diet. In many researches the positive effect of fruit and berry intake on human health has been reported. Anthocyanins are considered to contribute to the healthiness of fruits and berries for their antioxidant, anti-carcinogenic, anti-inflammatory and anti-angiogenic properties for example. Anthocyanins can also improve the nutritional value of processed foods by preventing oxidation of lipids and proteins in the food products. However, the stability of anthocyanins becomes most significant also in this case, as in the case of color quality. In this study the anthocyanin pigment was extracted from the three different berries (Morus nigra L., Morus alba var. nigra and Fragaria L.). Using the soaking and wetting in ethanol (1% acidified). The extracted anthocyanin pigments then were exposed to three different concentration of SO2 (25, 50, 100 ppm). Three groups of anthocyanin solutions keeping in darkness and refrigerator for 63 days and per 3 week, the quantity of anthocyanin absorbance recorded in 520 nm.