Abstract:

Based on the determined levels of iodine in blanching water, rinsing water and blanched kelp, leaching patterns
of iodine were investigated during the process of blanching and rinsing. The iodine concentrations in blanching water and
rinsing water revealed a gradual increase until reaching a stable level with increasing amount of kelp. From the cumulative
extraction curve of iodine in response to blanching and rinsing and the fitted equation, we found that the utilization rate of
iodine in kelp blanched at a solid-to-water ratio of 3 kg/L could be increased to 46% after several cycles of blanching and
rinsing. When comparing the extraction efficiency of iodine from kelp subjected to blanching alone and followed by rinsing,
it can be concluded that the extraction efficiency of iodine can be more than 15% in the effective extraction stage.

Key words: fresh kelp, iodine, blanching, rinsing