Anyone who regularly visits my Instagram feed knows that I am a ridiculous uni (sea urchin) addict. But I wasn’t always like that. Decades ago, when I first started eating sushi (which is how I first encountered sea urchins), I was very turned off. That’s because if uni isn’t super fresh, it can take on a rather pissy smell and the taste can similarly have an ammonia-like flavour that is rather off-putting.
Fortunately, thanks to better and more regular air freight, it’s become easier to enjoy ultra fresh and thus very delicious sea urchin. I’ve previously posted some ways to cook with or serve this marvelous ingredient, so today, instead of yet another recipe, I thought I would offer you some food trivia.
So, here are 10 things you probably didn’t know about sea urchins.
1. These spiky little sea creatures used to be called sea hedgehogs.
2. There are over 200 types of sea urchins but only a small handful are consumed by us humans.
3. The five plates that surround the mouth and the innards are called “Aristotle’s Lantern’. This is because Aristotle wrote a book entitled, “The History of Animals”. In the book, he describes the mouth a sea urchin looking much like a lantern.
4. Uni is the Japanese name for the edible part of the sea urchin, not the sea urchin itself. In other words, uni refers to the edible orange lobes.
5. These lobes are actually the animal’s gonads, which produce roe/eggs. Each sea urchin contains five ‘lobes’.
6. Uni is graded based on color, texture, and freshness. The highest grade is a bright yellow/gold (Grade A) with a firm texture and is a some sweetness. Grade B uni is a more muted yellow and has a softer texture and is less sweet. Grade C uni is referred to as ‘vana’ and is often the parts left over from uni that has broken apart during processing or handling. Obviously, the higher the grade, the higher the price.
7. Most uni that is served to us in better Japanese restaurants is Bafun uni. This is bright orange. Other popular uni used in sushi and sashimi restaurants include Murasaki uni (pictured above) and Aka uni. But the most highly prized uni is that from Chile, which the Japanese just call Chili-uni.
8. Uni is actually very healthy. A 100g portion of sea urchins contains 172 calories and very little fat. The fat is also almost all unsaturated fat. For every 100g of sea urchin, there are only 1.75 grams of polyunsaturated fat. And, we all know that eating polyunsaturated fats in place of saturated fats can help lower your cholesterol levels. Sea urchins also contain omega-3 fatty acids, which can help lower blood pressure and reduce the risk of an abnormal heart beat.
9. In the past, it was believed that sea urchins wee powerful aphrodisiacs
10. Scientists have discovered that uni contains an “euphoria-causing chemical” ingredient (albeit in very small quantities) similar to what you find in marijuana. Said ingredient is a chemical neurotransmitter called an anandamide, also known as arachidonoylethanolamide or AEA. Some say that this is why uni tastes so damned good.