Mirin
Often misunderstood in the West, mirin is a sweet rice wine that's essential for achieving that characteristic Japanese glaze and balanced sweetness. There are important distinctions to know:
Hon-mirin (True Mirin) - Contains around 14% alcohol and is naturally sweet from the fermentation process where the starches in glutinous rice are converted to sugars. This is what Japanese chefs use. It adds lustre to food, helps proteins retain moisture during cooking, and masks fishy odours. The alcohol content means it's sometimes sold alongside wines rather than in the Asian section, and you may need to show ID if you look under 25.
The fermentation takes around 40 to 60 days, during which koji mould breaks down the rice whilst alcohol develops. This creates a complex sweetness quite different from simply adding sugar—there's depth and subtle umami alongside the sweetness.
Aji-mirin or Mirin-fu Chomiryo - These are "mirin-style" seasonings with less than 1% alcohol, often with added corn syrup or glucose. They're more readily available in UK supermarkets (Tesco, Sainsbury's) but lack the depth of true mirin. If you're using these, you may need to adjust the quantity as they're often sweeter and more one-dimensional.
Shin-mirin - A newer style with around 8-9% alcohol, sitting between hon-mirin and aji-mirin in both alcohol content and quality.
In cooking, mirin is typically added towards the end to preserve its aromatic qualities. It's a key component in teriyaki sauce (literally "teri" meaning lustre, "yaki" meaning grilled), sukiyaki broth, and countless glazes. The alcohol burns off during cooking, leaving behind that characteristic glossy finish you see on yakitori or glazed salmon.
Once opened, store hon-mirin in a cool cupboard where it'll keep for three to six months. The alcohol acts as a preservative. If you see any crystallisation around the cap, don't worry—that's just sugar, perfectly normal.
