What To Know If You Plan On Stocking Up On Sweet Onions

Avid home chefs can appreciate the unique properties, flavors, and textures that different types of onions bring to various culinary creations. If you're the type of grocery shopper who likes to stock up on onions, given their reasonable shelf life at room temperature, you may want to reconsider that approach when shopping for sweet onion varieties such as Vidalia, Texas, Maui, and Walla Walla. Unlike their pungent cousins and siblings of the Allium genus, sweet onion varieties have a narrower post-harvest window when their sweet flavors can be enjoyed to the maximum. 

The natural sweetness of sweet onions is not necessarily because of extra sugar content, but rather because they have less sulfur and are less pungent than other onion varieties. For this reason, the flavors might not be as potent in your recipes if you're looking for a direct one-for-one swap with stronger onions. The decreased pungency is attributed to less pyruvic acid concentration, which is measured using the pyruvate scale. Pyruvic acid is produced during the biochemical process that forms syn-propanethial-S-oxide, the agent responsible for the tears shed when cutting Alliums that rank high on the pyruvate scale. On a 10-point scale, sweet onions rank low, between one and three, while more potent varieties rank over five. As a result, sweet onions have a less sharp profile, and don't trigger the water works as easily.

Time is of the essence if you want to capture all the glorious flavor that your sweet onions have to offer. Their slightly elevated water content contributes to a shortened shelf life, plus the skins of sweet onions are thinner than others and can bruise more easily. In addition, reduced sulfuric compounds, which play a defensive role in protecting the onion from pesky microbes, contributes to a diminished shelf life when compared to other varieties. Over time, their pungency may also increase, which decreases the sweetness of sweet onions. 

When stored properly at room temperature in a cool, dark, dry space (and not piled on each other), sweet onions can keep well for a week or two or up to two months, depending on the variety. For prolonged storage to the tune of up to six months, the veggie bin in your fridge comes in clutch.

There is no shortage of scrumptious recipes where sweet onions take center stage. The Vidalia variety in particular is recognized as the best choice for an onion casserole owing to its more subtle flavor when compared to standard yellow onions; the delectable sweetness also renders complex flavors to the dish without overpowering the other components. For a nourishing, South Indian-inspired breakfast, you can whip up an onion chutney to pair with your dosai (fermented rice and lentil crêpe) or idli (fermented rice and lentil cake). If you're tuned into the TikTok world of food trends, you may be aware of the viral onion boil hack. By using sweet onions, you get a mouthwatering onion boil that boasts a harmonious blend of aromatic flavors and a delicate, buttery mouthfeel.

Those inspired by fusion cuisine and culinary creativity may also enjoy cooking with sweet onions in ingenious preparations such as a warming, flavor-packed bowl of French onion ramen. For an elegant dinner party, you are guaranteed to please with a caramelized sweet onion pasta with a twist: The trick is to infuse notes of delicate smokiness by adding splashes of whiskey to the onions through the caramelization process. The smoky undertones from the whiskey complement the sweetness of the caramelized onions, producing a sophisticated plate of pasta. Naturally, there's always room for dessert; gear up for a pleasant surprise with a sweet onion and apple upside-down cake and reap the rewards of this coveted onion variety at its peak.