I still remember the fantastic aroma and taste of my very first homemade Yuzu Koshou. For those who have never heard about this Japanese product, yuzu koshou (sometimes written “kosho”) is a slightly bitter, slightly tangy and definitely hot paste made with chilli and yuzu citrus, which gives it a unique fascinating aroma. It is used as a condiment in soups, with tempura or for example grilled meat. Personally I appreciate its scent and mixture of flavours especially in ramen soups and was of course very proud and happy my homemade version proved excellent. Unfortunately, I am unable to buy yuzu fruits here, but instead of going back to the very expensive commercial version, I decided to experiment with other citrus fruits, trying to reproduce the combination of bitter and hot flavours I am so fond of.
Lime zest was my first attempt and, even though its scent is not as strong and as complex as yuzu’s, the paste does smell beautiful and has a similar hot taste, with a slight touch of bitterness. It works perfectly in my ramen soups, giving them a refreshing kick, particularly welcome in the middle of winter. In short, I think this is a more than acceptable substitution for all those who cannot get fresh yuzu zest.
Apart from the yuzu replacement with lime, I have followed here Nancy Singleton Hachisu’s recipe from Hachisu’s Japanese Farm Food.
If you are one of those lucky people who have access to yuzu, check the homemade Yuzu Kosho recipe here:
TIP: The jar contents taste better after several days in the fridge and then keep up to one month (it can be frozen too).
You can use any chilli peppers of any colour, green one being slightly more pungent.
Preparation: 10 minutes + several days in the fridge
Ingredients (yields one 150 ml jar):
zest from two limes (chopped or grated, but make sure you don’t take the bitter white pith)
10 heaped teaspoons chopped chilli peppers (seeded or not)
2 flat tablespoons salt
Mix everything in a food processor (baby food processor is perfect here) or grind in the Japanese mortar (suribachi).
Put into a jar, cover and refrigerate.
Start eating after several days.
Raimu koshou keeps for at least a month in the fridge.