Affiliations: [a] Ing. Biológica, Laboratorio Ciencia de los Alimentos, Facultad de Ciencias, Universidad Nacional de Colombia – Sede Medellín. Medellín, Colombia
| [b] Ing. Química, Línea Colorantes, Tecnas S.A. Itagüí, Colombia
| [c] Ciencias Químicas, Laboratorio Ciencia de los Alimentos, Facultad de Ciencias, Universidad Nacional de Colombia-sede Medellín. Medellín, Colombia
Corresponding author: Tania Rocío Jaimes Gualdrón, Universidad Nacional de Colombia-sede Medellín, Carrera 65 # 59A-110, Colombia. Tel.: +57 4 4309381; E-mail: [email protected].
Abstract: BACKGROUND:Oxidation is a deteriorating process in foods that affects sensorial quality and nutritional value. As a result, there has been a tendency to develop and consume functional antioxidant foods which delay oxidative processes. Anthocyanins are polyphenols which have been associated with high antioxidant activity. OBJECTIVE:To study the protection effect of corozo and grape extract with high anthocyanin content, on the oxidation time of yogurt. METHODS:Colorimetric and fluorimetric assays were used to determine anthocyanin content and antioxidant capacity in the extracts over time. For the yogurt, total phenol content was evaluated and antioxidant capacity by ABTS and ORAC. Also, the pH and color parameters (CIELAB - L*a*b*) were determined for the extracts and the yogurt. Finally, the oxidation of lipids and proteins in the yogurt were determined. RESULTS:A mixture of extracts from corozo and grape had good oxidative stability during the first month of study. There was also protection from oxidation in proteins and lipids during the 21 days of study in a yogurt prepared with the mixture of extracts. CONCLUSIONS: The extracts prepared from corozo and grape are adequate to be used as protectors of oxidation of macromolecules in yogurt.