Mix equal parts soy sauce and citrus juice, add a splash of rice vinegar and a small piece of kombu, and leave it to sit for a day. That is homemade ponzu, a sharp citrus soy sauce used as a dipping sauce and dressing.
Traditional ponzu uses yuzu, a Japanese citrus fruit that is hard to find fresh in the UK. Lemon and lime together get close enough for home cooking.
The basic ratio
Combine equal parts soy sauce and citrus juice, a small splash of rice vinegar, and a small piece of kombu for extra depth. Leave it in the fridge for at least a few hours, ideally overnight, so the flavours meld together.
Which citrus to use
A mix of lemon and lime is the easiest UK swap for yuzu, giving a similar sharp, floral citrus note. Some cooks add a small amount of grapefruit juice too, for extra complexity.
How to use it
- A dipping sauce for gyoza or shabu shabu.
- A dressing for a simple salad or cold tofu.
- Drizzled over grilled fish or vegetables.
Adjusting the balance
A basic homemade ponzu of soy sauce, citrus juice, rice vinegar and a little mirin can be adjusted noticeably by the citrus you use, yuzu gives the most traditional floral sharpness, but lime, lemon or a mix of orange and lime all give a good result if yuzu is not available. Taste and adjust before serving, since citrus acidity varies a lot between fruit and even between batches of the same fruit.
How long it keeps
Homemade ponzu keeps in the fridge for around a week, since fresh citrus juice does not preserve as well as the commercial version, which is typically pasteurised. Make a smaller batch you will use up quickly rather than a large batch for storage.
What is ponzu?
Ponzu is a Japanese citrus sauce. In its simplest form it is citrus juice mixed with vinegar and steeped with kombu and bonito flakes. The version most people buy, ponzu shoyu, also includes soy sauce, so it is salty, sour and savoury at once.
It is thinner and lighter than most dipping sauces and is used to add brightness rather than richness.
Dishes that suit ponzu
- As a dip for gyoza, shabu shabu and hot pot.
- Over grilled fish, steak or chicken.
- As a dressing for salads, cucumber or cold tofu.
- Drizzled on sashimi or seared tuna.
- Mixed with a little oil as a quick marinade.
Frequently asked questions
How long does homemade ponzu keep?
About a week in the fridge in a sealed container. The citrus flavour is at its best in the first few days.
Can I use bottled lemon juice?
Fresh is better, since bottled juice often lacks the brightness that makes ponzu work, but bottled will do in a pinch.
