Akajiso juice (red shiso cordial)
Bunches of red shiso fill Japanese greengrocers for a few weeks in June and July, mostly bought to colour umeboshi. Gardeners from Kyoto's Ohara valley to Kantō boil the surplus into this cordial and keep it in the fridge for hot afternoons. Simmering pulls a murky purple-brown liquid from the leaves; the magic is the moment the vinegar goes in and the whole pan flushes a brilliant clear magenta. Diluted with ice water or soda water it tastes sweet-sour and herbal, like a cross between blackcurrant, mint and cinnamon. The most common mistake is simmering the leaves too long or with the stems: it turns grassy and bitter. Strip the leaves, boil them for five minutes only, until they have turned green and limp, then lift them out. The cordial is ready when it is jewel-bright and clear. Bottle it in a clean, sterilised bottle and keep it in the fridge for up to three weeks; discard if it fizzes, clouds or grows mould. No fresh red shiso nearby? Japanese and Korean shops sometimes sell it in summer, and it grows easily from seed. Chef's tip: freeze some as ice cubes to drop into sparkling water.
Japanese
