The Special Oranges You Need For Copycat Costco Mimosas
Costco's Kirkland Signature Mimosa seems to have amassed a fan club: While some commenters on the retailer's Instagram dismissed the affordable cocktail as "too orange," that's technically how a mimosa should look. After all, a classic mimosa is made from equal parts orange juice and sparkling wine (like Champagne, if you have it). In Costco's case, the secret to its store-brand mimosa is listed proudly on the label: Sicilian blonde oranges. If you were to try to make your own in that style, what does "Sicilian blonde oranges" mean?
Specifically, the drink is made from Ribera oranges, or officially Arancia di Ribera DOP (Denominazione d'Origine Protetta or "Protected Designation of Origin," which means any oranges called "Ribera" must be grown in Ribera, Sicily). Ribera oranges are mostly seedless oranges with a very bright, intense color — you can see that bright "blonde" color reflected in the mimosa, which is very, very orange. Perhaps befitting that color, they're known to taste very sweet. So you would need similar bright, seedless types of oranges for your own version.
Blonde oranges and you
It would be difficult to recreate the Costco mimosa perfectly without importing ingredients, since Ribera oranges are specific to that part of Sicily. The drink uses a mix of oranges grown around that region, which are primarily Washington navel oranges. These get their name from a small dent in the rind, which vaguely resembles a belly button, which is actually caused by a mutation where a second fruit is supposed to grow. They're always seedless, which means they have to be cut or grafted to reproduce. Ribera oranges also include Navelina oranges, which are similar except for a smaller "navel."
While "blonde orange" isn't an especially common term, it generally includes pale, sweeter oranges like navels and Valencia oranges, compared to darker-colored citruses like Mandarin oranges or blood oranges. Valencia oranges are similarly bright-colored and sweet, although they do often have seeds. Your copycat mimosa would probably benefit from navel oranges, even if they're a type that's more local to your town than Sicily.
The Kirkland Signature Mimosa
Costco's Kirkland Signature Mimosa mixes that Sicilian orange juice with sparkling wine made from white Glera grapes. It's a lighter cocktail at 6% ABV (alcohol by volume), but as a trade-off, it's cheap: Only $7.99 for a 750-milliliter bottle that's designated as "ready to drink." It has a few servings and seems to be designed with brunch in mind, because often mimosas are brunch drinks. According to the bottle's label, the mimosa is produced and bottled in Italy before being imported to U.S. Costco stores.
Late in 2023, Costco briefly pulled them off the shelves due to quality control issues and offered refunds to customers who purchased them. It didn't appear to be a full recall and there wasn't a specific reason given, although one viral Reddit post from that time appears to show a dead bug in a Costco mimosa bottle. But, as of March 2024, Costco's official Instagram account responded to commenters saying the matter "has been resolved" and the bright orange Kirkland Signature Mimosa is back on the market.