| dc.description.abstract | Ulva species are green seaweeds belonging to the order Ulvales (Chlorophyta), rich in proteins, ash, fatty
acids and essential amino acids, and compounds with antioxidant activity. However, their chemical
composition is affected by environmental conditions, geographic location and processing. Drying is the
traditional process that has been used for many centuries to preserve seaweed. However, the selection of
suitable drying methods and conditions are of great importance to produce quality-drying seaweed.
Therefore, a characterization of Chilean Ulva spp. was done to describe the effect of drying (freeze-,
vacuum-, solar- and convective-drying) on its potential as functional food. The method and drying
conditions were: freeze-drying (FD) at a vacuum pressure of 200 mTorr for 73 h; vacuum drying (VD) at
Amino acid profile was determined
by a HPLC equipped with a UV detector and a post-columnn ninhydrin derivatization, whereas fatty acids
were determined as methyl esters (FAMEs) by gas chromatography. Antioxidant activities were assessed
by DPPH and ORAC assays. The results in this study showed that the highest degradation ratio of amino
acid with respect to FD sample was found in CD product (31.9 %) followed by SD (24.6 %) and VD
healthy diet. Different trends were obtained for antioxidant capacity by DPPH and ORAC assays, both
reduced antioxidant capacity compared to fresh samples, but DPPH presented a mean reduction close to
80 % while ORAC reduction was only 10%. Consequently, dried Ulva spp. could be used as a functional
ingredient. | |
