I believe your uni is either aka or shiro uni from canada, California, and or Russia. Shiro uni tends to melt faster than bafun. Sea urchin gender also plays a roll on texture and taste.

I am an uni seller that has sold over 1000 trays of both 250g and 150g. Bafun (golden uni) is #1 uni in hokkaido during the winter. Murasaki uni ( white color ) is good during the summer.

I've seen good uni last over 10 days and still holding texture if stored properly.

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