Last days to make Elderflower Cordial

My Elder has been thrashed by the thunderstorms so last week was my last chance to make Elderflower cordial before the last of the flowers went brown. As an experiment I put half the flower heads in the freezer to see if it would be easier to remove them from their stalks - big mistake. They did come off fairly easily but within minutes went brown and horrible. From now on I'll stick to combing them off with a fork. I put some of the lemon and flower water in a bottle and added hibiscus tea, the colour was so summery. Here they are in bud and flower...