Green Walnuts: an elegantly bitter harvest
Story, recipes, and photos by Kristen Rasmussen
Most of us are familiar with the taste of dried walnuts. We crack them open by hand for a snack, toast them to toss into a salad, or delight in finding them baked into our brownies. Fresh green walnuts, on the other hand, offer a taste that few have enjoyed, the primary reason being that they are incredibly bitter. Fortunately, we can use simple processes to remove the tannins from these acrid green gems and transform them into something dark, deeply flavored, and refined.
California has an indigenous black walnut tree (Juglans californica), but the walnut species we’re most likely to cultivate locally is the English walnut, Juglans regia, which is thought to have originated in Persia. Most historic documented uses of the English green walnut are from Europe, where cooks have used them through the centuries to make chutneys, pickles, liqueurs, and infusions. The recipes below both take time, but you wind up with a rich and luscious Italian liqueur and a pungent and sharp English-style pub pickle that are well worth the effort.
Walnuts for the Italian liqueur called nocino are traditionally harvested on June 24, the feast day of St. John the Baptist. The work and the festivities always include a tasting of the previous year’s nocino production. Not a bad way to go about it!
Walnut trees in the Bay Area are usually found in hot, dry climates, so it’s best to harvest the green walnuts in late May through the end of June before they have matured. I have harvested green walnuts as late as September, using them to make a less elegant (but still tasty) nocino and pickled walnuts with a hard, inedible center where the shell has begun to form.
Foraging is easy. Simply pick the walnuts from the tree as you would any fruit and drop them into a bag. They can be held in a cold, dark space for up to a week prior to processing. Remember that foraging on most land is illegal, so if you happen to have a friend with a walnut tree, that is the way to go. Keep your eyes open at the farmers’ market and you might find some nut farmers selling green walnuts, or you can contact the farms directly to inquire about purchasing some.
Processing and Pickling Green Walnuts
Be aware that green walnuts produce an inky stain, so wear black or old clothing while processing, and if you don’t want to show off inky fingers for a week as a badge of honor, be sure to use gloves.
When green walnuts are cured in a brine and sun-dried, they become something akin to fleshy, tart-flavored olives. Be sure to use walnuts harvested early enough that they are easy to cut through, otherwise the inner shell will not be edible.
Pickled Green Walnuts
My favorite way to enjoy these pickles is on crostini with a sharp cheese, such as cheddar. Garnish with fresh herb, such as chervil, for a bit of brightness.
Yields about 2 quarts.
- 30 green walnuts
- ¼ cup kosher salt
- 1 quart water
- 1 quart apple cider vinegar
- ½ cup granulated sugar
- 1 tablespoon dark molasses
- 1 tablespoon black peppercorns
- 1 tablespoon allspice berries
- 5 cloves
Wash a half-gallon jar well with hot soapy water, rinse, and air dry.
Add salt and water to jar and stir to dissolve the salt. Stab each walnut with a fork a few times to help the brine penetrate the flesh, then submerge and let them ferment for 10 days at room temperature.
Remove walnuts from the brine, place them on a baking sheet or other tray, and let them sit in the sun for 24 to 48 hours, or until they turn completely black.
Wash 2 quart jars well with hot soapy water, rinse, and air dry. Divide the walnuts evenly into these jars. Bring the vinegar, sugar, molasses, and spices to a boil then pour over the walnuts. Try to leave little headspace in the jars (if you need more liquid, add a bit more vinegar). Seal jars and let rest in a cool, dark place for at least a month.
Pickles can be eaten for up to 1 year.
Anyone can magically transform incredibly tannic walnuts and clear, sugary alcohol into this “black gold” Italian liqueur. I like to keep my nocino pure so I can taste the walnut-y goodness but have successfully experimented with adding vanilla bean and cinnamon. Try pouring nocino over vanilla ice cream, using it in a Manhattan cocktail in place of vermouth, or drinking it on its own as a digestif.
This recipe makes about 2 liters, but you can multiply it as necessary according to the amount of walnuts that you have on hand.
- 4¼ cups granulated sugar
- 1.75 liters Everclear (Vodka can also be used, but I strongly prefer the strong stuff, as it leads to a more robust flavor.)
- 50 green walnuts, cut in quarters
- Optional flavorings: citrus peel, cinnamon sticks, black pepper, vanilla bean, etc.
- 4 half-gallon jars with lids, washed well with hot soapy water, rinsed, and air dried
- Smaller bottles with lids
Divide the quartered walnuts, Everclear, and sugar evenly into the cleaned jars, then screw on the lids tightly and shake the jars vigorously. Over time the nocino liquid will darken. It happens quite fast and it’s pretty impressive! Allow jars to sit for 6 weeks in a cool dark place, shaking occasionally to dissolve sugar.
Using a cheesecloth or fine mesh strainer, strain the liquid and discard the walnuts. Add any optional ingredients (vanilla bean, orange peel, etc.) and pour nocino from the jars into smaller bottles with tops, which you have washed well with hot soapy water, rinsed, and air dried. Close bottles and allow the liqueur to mature for another 6 months to 1 year. Feel free to taste the nocino as it rests to learn about the flavor changes, then begin drinking once you find it to your liking.
What could be better that a scoop of vanilla ice cream with chopped walnuts, drizzles of nocino and extra virgin olive oil, and a sprinkle of sea salt? We can’t think of anything.