Effects of four different drying methods on the carotenoid composition and antioxidant capacity of dried Gac peel

BACKGROUND Gac fruit (Momordica cochinchinensis Spreng.) is a rich source of carotenoids for the manufacture of powder, oil and capsules for food, cosmetic and pharmaceutical uses. Currently, only the aril of the Gac fruit is processed and the peel, like the other components, is discarded although it contains high level of carotenoids, which could be extracted for commercial use. In the present study, four different drying methods (hot-air, vacuum, heat pump and freeze drying), different temperatures and drying times were investigated for producing dried Gac peel suitable for carotenoid extraction. RESULTS The drying methods and drying temperatures significantly affected the drying time, carotenoid content and antioxidant capacity of the dried Gac peel. Among the investigated drying methods, hot-air drying at 80 °C and vacuum drying at 50 °C produced dried Gac peel that exhibited the highest retention of carotenoids and the strongest antioxidant capacity. CONCLUSION The hot-air drying at 80 °C and the vacuum drying at 50 °C are recommended for the drying of Gac peel

Influence of pretreatments on quality parameters and nutritional compounds of dried galega Kale (Brassica oleracea L. var. acephala)

The objective of this work was to evaluate the effect of six pretreatments on quality and nutritional contents of sliced Galega kale submitted to convective drying. Among all treatments, steam blanching was the most favourable, allowing improvements in retention of vitamin C, total antioxidant capacity and chlorophylls in comparison to the absence of pretreatment. Total phenolic losses were not reduced by steam blanching, but the retention was improved by combining this approach with a previous immersion in a metabisulphite solution. Moreover, steamblanching improved the colour parameters and appearance, providing a final dried product more similar to the fresh sample.info:eu-repo/semantics/publishedVersio