Antioxidant activity and sensory analysis of murtilla (Ugni molinae Turcz.) fruit extracts in an oil model system

Abstract

An oil model system was used to analyze the antioxidant activity of Chilean fruit extracts and to determine their odor sensory effect. Hydroalcoholic extracts from wild and 14-4 genotype murtilla (Ugni molinae Turcz.) fruit were assessed by the Response Surface Methodology. The optimal conditions for producing high total phenolic-content extracts were 49.5% (v/v) ethanol at 30 ºC, which yielded 18.39 and 26.14 mg GAE·g-1 dry matter, respectively. The optimized extracts were added to a lipid model system and evaluated via the Schaal Oven Test. After 96 hours, 150 and 200 mg·kg-1 oil of the wild and 14-4 genotype extracts, respectively, showed an antioxidant capacity similar to TBHQ (200 mg·kg-1 oil) in terms of peroxide values and odor. Thus, murtilla fruit extracts are a natural source of antioxidants for protecting lipidic foods, such as soybean oil.

Keywords

• antioxidant activity
• murtilla
• oil model system
• oil organoleptic characteristic
• response surface methodology
• total polyphenol content