Hello, I’m Andrea Castillo and this is Seasonal, a newsletter that connects you to the Bay Area food system, one fruit and vegetable at a time. Each post highlights the most interesting aspects of one seasonal fruit or vegetable grown and harvested around the Bay Area. Seasonal is a public good, and all past and future posts are free to read, but if you want to support my quest to deepen our connection to food and contribute to building a stronger food community, please consider becoming a paid subscriber for $5/month. Find me on Instagram at @seasonalbayarea or e-mail me at seasonal@substack.com to share your feedback and suggestions, I’d love to hear from you. If you’d like to unsubscribe, click the link at the bottom of this post.
This week we nerd out on parsley (available year-round).
aroma clouds
Do you remember the lovely pine aroma the last time you walked in a forest, the woody scent after grinding fresh spices, or the fresh, grassy punch to the nose after chopping a handful of herbs? What you’re smelling is an invisible molecular cloud that trees, spices, and herbs release to either repel unwanted visitors or attract attention. Those molecules can trigger memories, improve our mood, enhance our health, and also entice us to not just smell, but taste. When we eat herbs we taste tiny molecules in leafy plants that deliver big flavor. Parsley, a powerful herb, releases fragrant molecular clouds when cut or torn, overpowering or delighting the curious eater.
This leafy, potent member of the carrot family adds color, enlivens sauces, or dominates by the cupful in salads. Above all, parsley’s greatest contribution to our eating experience is a teensy group of molecules trapped within its essential oils.
rousing oils
Parsley resorts to chemical warfare to keep pests away—a classic defense system in the plant world. When bitten, torn, or cut, parsley’s oil glands release potent chemicals, repelling hungry herbivores. For humans, however, parsley’s defense system is a sensory treasure trove. The oils that work so well against pests deploy molecular compounds that create bright aromas and distinctive, strong flavors for hungry diners. Some of parsley’s flavorful molecules, like phellandrene, are common in all kinds of plants like dill and conifer trees, whereas apiole and 1,3,8-p-menthatriene are rare in edible plants but common and sometimes dominant in parsley.
In fact, the 1,3,8-p-menthatriene molecule is vital to parsley’s taste. But, much like a single piccolo could never deliver an entire symphony on its own, 1,3,8-p-menthatriene needs other molecules to create parsley flavor. In a symphony, the piccolo has its forte—loud—moments while other instruments scale back to a more piano—soft—role. When we taste parsley, we’re tasting different concentrations of dozens of chemical compounds in its oils, some more “forte” than others. Just as a composer determines how each orchestra instrument contributes to the symphony, parsley type and harvest time determine specific molecular concentrations that create distinct flavors.
to curl or unfurl?
There are two main types of parsley—curly and flat-leaf—and even though the molecules we ingest in each plant are similar, their amounts vary depending on whether the leaves are curly or flat.
Parsley is native to Southern Europe where it has been cultivated for 2,000 years. Parsley was used as medicine first, then as horse fodder, and finally in cooking around the middle ages. It took a while for cooks and eaters to trust parsley: the flat-leaf variety looks similar to fool’s parsley, a deadly relative, and a well-founded fear got in the way of enjoying it. But then, curly parsley came to the rescue. The distinct furled leaves in curly parsley were the antidote to fool’s parsley’s trickery and parsley finally made its way into our food.
Over time, the French grew fond of curly parsley. When French cuisine dominated cooking styles in the United States, curly took the center stage as a pretty but tasteless garnish no one ate. But flat-leaf parsley, also known as Italian parsley, challenged the passive and often wasteful role of garnishes, offering something worth eating for a change. The new flat-leaf parsley trend caught on, stealing the show (it’s not a perfect way to gauge popularity, but “Italian parsley” outnumbers “curly parsley” by a long shot in recent Google searches and trends).
For many, flat-leaf parsley delivers a bold taste they prefer over the milder curly parsley taste. Others still prefer curly because it tastes sweeter, does not overpower, and is easier to chop. There are strong opinions in the curly vs. flat-leaf debate (440 upvotes and counting on this curly parsley Subreddit alone!), one side baffled by how the other could enjoy their preferred choice. How did this herb amass its polarizing powers? The invisible treasure troves within parsley’s oil glands have a lot to do with it.
Two distinct flavor bundles exist in the parsley world: in the first group, 1,3,8-p-menthatriene molecules dominate while in the second, a volatile compound known as myristicin reigns (there’s a third, smaller bundle that’s apiole dominant). Typically, flat-leaf parsley belongs in the first group, while curly parsley belongs in the second.
Flat-leaf parsley can have as much as 10 times the amount of 1,3,8-p-menthatriene—the “parsley flavor” compound—compared to curly parsley. On the other hand, myristicin, an aromatic, nutty chemical compound in nutmeg, can make up to 40% of the compounds in curly parsley’s oils. Sometimes myristicin isn’t even detected in flat-leaf parsley and apiole, another “parsley-flavor” molecule, can account for half the essential oils in flat-leaf but only less than 1% of the oils in curly. If you’re a fan of strong parsley flavor explosions and the nutmegy bites from curly parsley fail to meet your expectations, you’re experiencing parsley’s polarizing superpowers! Still, curly and flat-leaf parsley differences are not always so pronounced: in the parsley universe, timing can be everything.
like clockwork
Parsley qualities—strong, fresh, sweet, mild—also vary depending on the age of the parsley being eaten. The quantity of the volatile molecules in parsley’s oils change throughout the life of the herb. Younger flat-leaf parsley, for example, generally tastes stronger because there is a higher concentration of chemicals within the plant’s oils. When harvested on day 78, the unique 1,3,8-p-menthatriene molecule can make up to 48% of the essential oils in flat-leaf parsley but reduces to 38% when harvested on day 144. As 1,3,8-p-menthatriene wanes with time, so do the majority of flat-leaf parsley’s oils, deteriorating parsley’s taste (in a Spanish study, a panel of trained food quality experts agreed that the younger flat-leaf parsley was much more desirable than the more mature one). Curly parsley, on the other hand, starts mild but its flavors intensify when harvested later: levels of myristicin increase over time, in some instances from 25% to 76% in one month—a transformative change in such a short time! In addition to chemical changes over time, there’s a seasonal aspect to parsley flavor.
The mild climate in Monterey and Ventura Counties in California is a haven for parsley and both counties grow most of the state’s parsley year-round. Despite ‘round the clock availability, parsley won’t always taste the same throughout the year. California, with its Mediterranean-style climate, does not experience extreme changes in a way that Vermont would with below-freezing winters and hot and humid summers. Nevertheless, California parsley crops do experience changes in moisture, temperature, and amount of sunlight throughout the year. Seasonal variations, in turn, alter parsley’s internal chemical make-up. Like a stock market reacting to external events, parsley’s aromatic molecules respond to environmental changes by reaching new highs or free-falling, resulting in new flavor offerings. For example, parsley grown in Greece, a country with a similar climate to California, had a higher concentration of apiole when harvested in spring than in winter. In Spain, curly parsley picked during droughts tastes stronger: the lack of water concentrates the oils in the furled leaves.
From a recent trip to my other home: a Colombian chef’s flat-leaf parsley ready for chimichurri.
tiny and mighty
Types of parsley and harvesting schedules play a big role in determining parsley flavors. In addition, the amount of water, frequency of irrigation, type of fertilizer, soil chemistry, storage temperature, or time in storage could also tweak the molecular concoction that makes parsley taste like… well, parsley. But no matter the reason, it’s fascinating that a minuscule component of a humble herb can awaken our senses so powerfully. And, while strong, those mighty molecules taste best in a group setting. Parsley by the spoonful with nothing else isn’t that pleasant—no judgment if that’s your thing! But once parsley’s grassy, hereby, and woody elements join garlicky, fatty, and acidic ingredients, they add a wonderful intensity to a meal.
by the bunches
Instead of dishes that call for one or two tablespoons of parsley, I want to highlight ways to use the whole bunch. I find it easier to prevent food waste when cooking this way. Plus it’s a great way to get all the vitamin A, K, and C you need!
Make a sauce and a condiment with one bunch. With half a large bunch of parsley, try Francis Mallmann’s Argentinian classic, chimichurri: a parsley and oregano sauce served with steak that also goes well with grilled vegetables. With the other half, try making a simple Italian gremolata with lemon, mandarin, or orange zest, especially in late fall, winter, and early spring when citrus is at its peak in California. Sprinkle this condiment on most meats and roasted vegetables.
When days of summer are over and basil is no longer abundant, Italian parsley pesto uses at least a bunch of parsley and is a great alternative to go with your pasta or toast. Fanny Singer’s take on another Italian classic, salsa verde, makes for a versatile sauce that’s excellent chicken, fish, roasted winter squashes, potatoes, or boiled eggs. Grab another bunch for a Moroccan chermoula sauce—a beautiful mix of herbs, olive oil, lemon, and garlic that will bring any roasted, braised, or blanched vegetable medley to life. I like Paula Wolfert’s recipes in her The Food of Morocco book and this chermoula recipe from Nada Kiffa.
Before we hop off the sauce train, there’s one more sauce that’s worth making: zhoug! Zhoug, a spicy chutney from Yemen, is often made with cilantro, but there are variations with parsley, like Ottolenghi and Tamimi’s version from their Jerusalem cookbook. Zhoug is a wonderful green kick for your veggie bowls, meats, or sandwiches.
If you’ve got two or more bunches of parsley, the deep green kuku sabzi, a Persian dish that is mostly herbs held together with just a little egg has your back. It’s a great fall and winter dish, especially if using seasonal pomegranates and walnuts as toppings. Similarly, the popular tabbouleh salad is a great way to use up a bunch or two of parsley, especially the style of tabbouleh that’s parsley-heavy with a little bulgur. Tabbouleh uses tomatoes, making it an excellent choice for salad in the summer. Another simple salad I learned to make from friends is a protein powerhouse with ingredients available throughout the year. To make it, mix the following in a bowl: 2 cups cooked chickpeas (canned and drained works as well), 1 to 2 cups chopped parsley, lots of grated parmesan, squeezed lemons (4 or so), 3 long pours of extra virgin olive oil, and salt and pepper to taste. It freezes well and is great to bring on camping trips as an edible ice pack!
If you don’t intend to cook with the parsley you purchased earlier in the day, make sure to store it in a jar with water like a bouquet in the fridge with a bag on top so it stays fresh longer (change the water every three days or so). When you are ready to cook with it, use a sharp knife: parsley leaves are delicate and a blunt blade will smash the leaves instead of slicing them, dulling their color and flavor. If you’re only using the leaves, don’t toss the stems! Save them in a bag in the freezer so you can make a savory stock later.
Experiment a little with different parsley as you explore this potent herb. Take a moment to explore your preferences and keep them in mind as you put parsley’s oils to work next time. What works is what you like, a recipe is a simple guide. I’ve seen plenty of tabbouleh recipes, for example, that call for curly parsley but my Lebanese godmother would never use curly in her tabbouleh. I happen to agree with her, but it’s because I go for strong, bold flavors in everything (I always quadruple cinnamon quantities in recipes, for example). If you can’t stand parsley, maybe that 1,3,8-p-menthatriene does not agree with you and that’s okay: parsley isn’t for everyone. If parsley is too overpowering to eat by the cupful, perhaps a young curly parsley with low levels of essential oils would be more appealing. On the other hand, if a tablespoon of parsley in a recipe is laughable because there’s no way that’s powerful enough, maybe you’d enjoy the extra oomph from a young flat-leaf or a more mature summer curly parsley.
escape artists
Essential oils account for a tiny fraction of parsley, weighing in at a mere 0.3% of the total plant mass. Tiny as they may be, the chemical compounds in those oils sweep us off our feet the second we free them from their confined space. However, their volatile nature means that once they’re free, they really want to escape and don’t linger for too long. As they disappear into the ether, they take their aroma and flavor away with them.
Flavor is a huge reason why parsley, like arugula and other delicate greens, is best fresh. Unlike hardy vegetables that keep well for weeks—think onions or winter squashes—the sooner you eat parsley after farmers harvest it, the more you’ll be able to taste its essential oils. To make the best of what these mighty molecules have to offer, locally grown parsley will be one of your best bets. Local parsley won’t have to travel too long or too far to get to your cutting board. Better yet, give an herb garden a go if it’s available to you. You can optimize for your personal parsley preference, growing your favorite type and harvesting it when you want to. Honor those tiny chemical escape artists and chop, tear, or mince fresh parsley right before adding it to a sauce, condiment, or salad. Your tastebuds will thank you for the impermanent but healthy and delightful treat!
Liked parsley? Nerd out on makrut limes, radishes, or puntarelle next.
Thank you for nerding out with me, and a special thanks to paid subscribers for your support! If this email was forwarded to you and you'd like to sign up for the newsletter, click the button below:
Andrea Castillo is a food nerd who always wants to know the what’s, how’s, when’s, and why’s of the food she eats.