Antioxidants in Andean food and meals

Sammanfattning: Popular Abstract in English Popular scientific summary Interest in food and plants as sources of antioxidants has increased in recent years, since antioxidants are believed to have major health benefits. Food and plants have complex matrices made up of different compounds (polyphenols, antocyanidin, carotenoids, etc) that individually or jointly can act as antioxidants. Polyphenols and anthocyanidins are relatively small molecules of non-carbohydrate, non-protein, and non-lipid nature. They are commonly colored and have an astringent and bitter taste. Many of the studies of antioxidant activity have analyzed individual foods, but not combinations such as processed food. For this thesis, various kinds of foods and meals were collected in order to analyze antioxidant activity, and to identify and quantify the polyphenolic and anthocyanidin compounds. Antioxidant activity and polyphenolic content were analyzed, using spectrophotometric methods. Polyphenols and anthocyanidins were identified and quantified through the use of high-performance liquid chromatography. High antioxidant activity and high polyphenolic content in the hydrophilic and hydrophobic parts was reported in quinoa, a grain from the Andean region of South America. When Andean tubers such as white potato and a freeze- and sun-dried potato called chuño were compared with colored potato, slightly higher antioxidant activity was found in the colored potatoes, but the polyphenolic content was shown to be similar in both cases. The correlation between gene material and presence of anthocyanidins and polyphenols was investigated. The results showed a correlation, confirming the concept of the link between color and antioxidants. Antioxidant activity in processed food may be increased or decreased depending on the combination of individual food items and the cooking process. In some processed foods, antioxidant activity was slightly higher, and this was associated with higher fiber content. Antioxidant activity was evaluated in approximately 80 samples (individual and processed food). Based on the results it can be concluded that antioxidant activity in individual foods is overestimated in comparison with processed foods.