Know your Pearl Onion
Know your Pearl Onion - Introduction
Pearl Onions are small pearl-shaped bulbs that are usually 2 to 3cm (¾ to 1¼ inches) wide.
Their taste is sweet and mild, and they are grown mostly for pickling as a cocktail onion.
However, because of its unique diminutive appearance and much sweeter taste than a bulb onion, it has been used in dishes ranging from middle 20th century American casserole dishes such as succotash to sweetly-flavored onion relishes in Indian cuisine.
Know your Pearl Onion - Varieties
They are grown from many different varieties of onions, most of which would normally grow into regular-sized onions.
Species Allium cepa
Most pearl onions are produced from the species Allium cepa.
They are encouraged to grow small in several ways.
They can be planted closely together so that they grow small.
They can be harvested when still small.
A grower might plant short-day varieties in northern areas.
Species Allium ampeloprasum var. sectevum
In Europe, a common variety used for Pearl Onions (Allium ampeloprasum L. var. sectevum) produces a clump of small onion bulbs with white skins.
The plants form a clump of small daughter bulblets that may be used as pearl onions.
These are grown mainly in gardens in the east of Germany and, until recently, were grown commercially in the Netherlands.
The small bulbs can be grown from seed, but more typically are produced from bulblets.
At maturity each plant forms a cluster of short-stalked bulblets with silvery white skins.
These are traditionally pickled.
Know your Pearl Onion - Cultivation
White Pearl Onions are the most common, and the cheapest.
White varieties include Crystal Wax (aka White Bermuda). These have a very small neck, are mostly round, and are ready to harvest from seed in 90 days.
Producers allow them to dry a bit first before shipping them, so that they will store better.
You can buy them fresh, pickled or frozen (frozen will already be skinned.)
Fresh ones are usually packaged in small mesh bags, or in boxes, though sometimes they are sold loose.
Fresh ones should be heavy for their size.
Know your Pearl Onion - Cocktail Onions
Cocktail onions are pickled pearl onions.
They are small white mild flavored onions.
Few bars stock cocktail onions because they are only used to make a Gibson (classic Martini with onions instead of olives).
High end bars will stock them.
For the Gibson, one un-speared cocktail onion or two speared cocktail onions is proper.