Considering that only a small amount of fruit and vegetables are consumed in their raw state, the evaluation of influence of food processing on naturally occurring antioxidants is a key factor in finding those technological conditions necessary to preserve or improve their original activity and bioavailability. The aim of the present research was to make a preliminary study on the effects of freezing and freeze-drying on the antioxidant activity of two types of tomato cultivars. in clusters and oblongs. Results showed that a polyphenolic fraction is mainly present on the fruit skin in both types of tomatoes. It seemed that oblongs tomatoes had better percentage of polyphenols than those in clusters after freezing; the differences between the two types seemed to disappear after freeze-drying. About AAT, the results showed that the antioxidant activity was quite low, even if tomatoes in clusters were better than oblongs: technological treatments increased, in comparison with raw material, this quality parameter. On the other hand, DPPH radical scavenging activity was stable.
Lante A., Lomolino G., Spettoli P., Sambo P., Gianquinto G. (2006). Effect of freezing and freeze-drying techniques on antioxidant activity of tomato fruits. INDUSTRIE ALIMENTARI, 45(464), 1270-1272.
Effect of freezing and freeze-drying techniques on antioxidant activity of tomato fruits
Gianquinto G.
2006
Abstract
Considering that only a small amount of fruit and vegetables are consumed in their raw state, the evaluation of influence of food processing on naturally occurring antioxidants is a key factor in finding those technological conditions necessary to preserve or improve their original activity and bioavailability. The aim of the present research was to make a preliminary study on the effects of freezing and freeze-drying on the antioxidant activity of two types of tomato cultivars. in clusters and oblongs. Results showed that a polyphenolic fraction is mainly present on the fruit skin in both types of tomatoes. It seemed that oblongs tomatoes had better percentage of polyphenols than those in clusters after freezing; the differences between the two types seemed to disappear after freeze-drying. About AAT, the results showed that the antioxidant activity was quite low, even if tomatoes in clusters were better than oblongs: technological treatments increased, in comparison with raw material, this quality parameter. On the other hand, DPPH radical scavenging activity was stable.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.