Effect of thermal treatment and addition of olive oil on the antioxidant properties of tamarillo puree.

The study intended to determine the effect of temperature (100-200 °C), time (2-6 min), and oil on the bioactive properties and colour parameters of tamarillo puree. The increase in heating temperature (up to 175°C) and time increased the phenolic content, flavonoids content and antioxidant activity. Carotenoids were found to increase from 0.65 to 1.06 (mg β carotene/ g) in puree with oil heated at 200°C for 6 min. In puree with oil, the lightness (L*) and redness (a*) values of puree were found to be reduced, but yellowness (b*), hue angle and chroma improved with treatment temperature and time. Addition of oil exhibited positive influence on retaining the bioactive compounds in comparison to puree without oil, which can be attributed to their enhanced extractability. In conclusion, the desirable effect of heating temperature and time, and addition of virgin olive oil will be helpful in canning of oil enriched tamarillo puree.