These are invaluable when making flower jellies, and I have often used other than cooking apples. Granny Smiths are ideal, as they are tart but do not burst. Bramleys can be a problem, because they cook to such a soft mass that some of this escapes into the extracted liquid used when making jellies, although they are fine in jams and chutneys. One of the most unusual cooking apples I have used is the White Transparent, a Russian variety, which produces a very pale extract, and therefore a pale jelly; this is particularly useful when using pale flowers such as pink roses or carnations, elderflower or jasmine.