In the rolling hills and sun-soaked fields of Tuscany, cheesemaking is not only an art but also a deeply rooted tradition. From the elegant city of Florence to the historic streets of Siena (both cities are part of our Herbal Tuscany 2025 trip!), Tuscan cheesemakers have cultivated a unique process that sets their cheeses apart. Unlike most cheese varieties that use animal-derived rennet, some Tuscan artisans have turned to an unlikely source: the wild thistle flower. This plant-based rennet alternative gives Tuscan cheeses a distinct taste, reflecting the region’s commitment to heritage, sustainability, and respect for the land.

Thistle Rennet: A Plant-Based Tradition in Tuscany

Using thistle instead of animal rennet is not a recent trend. The practice dates back centuries, particularly among shepherd communities in the Mediterranean. Thistle is known locally as cardo, and it can mean any of a variety of thistles. In western herbal medicine, Carduus marianum (now called Silybum marianum) has traditionally been used as a liver “cleanser” and used for jaundice and hepatitis, while Cnicus benedictum, commonly called milk thistle or blessed thistle, has been traditionally valued as a galactagogue or breastmilk-supporting herb. They spread quickly and are covered in sharp and prickly spines, therefore they are not welcomed in most fields, though the flowers are favored by honeybees and butterflies, and the seeds have many uses.

Cardo has natural enzymes that coagulate milk, and Tuscan cheesemakers have perfected this method, harnessing its properties to create unique textures and flavors especially when making cheese from sheep’s milk. The stamens of the thistle flower are used to make thistle rennet. To make thistle rennet:

1. Grind dried thistle stamens into a powder using a mortar and pestle
2. Add the ground stamens to a bowl and steep in warm water for 10 minutes
3. Strain and reserve the liquid rennet 

Use one cup of thistle rennet per gallon of warmed milk.  As it ages, thistle rennet will break down proteins and give the cheese a softer and more yielding texture, at the same time supporting its mild and floral flavor since the rennet imparts slightly herbal, floral notes to the cheese. These qualities contrast thistle-rennet cheeses from the sharper, earthier profiles usually found in animal-rennet cheeses. As a result, cheeses made with thistle rennet have a softer, more delicate taste.

 Sometimes Tuscan cheese makers use other locally-grown or harvested herbs in their cheese craft, creating complex flavors that evolve over time. Examples include:

Rosemary (Rosmarinus officinalis, scientifically changed in 2017 to Salvia rosmarinus)  

Known for its earthy and slightly piney aroma, rosemary grows abundantly in Tuscany and is often rubbed onto the rind of cheeses. This adds a woody, slightly resinous character that becomes more pronounced as the cheese ages.

Thyme (Thymus vulgaris)  

Thyme, particularly wild thyme, has a delicate and slightly minty flavor. When included in cheeses, it complements the floral notes of thistle rennet, making the flavor profile more nuanced.

Sage (Salvia officinalis)  

This herb lends a savory, peppery quality and is sometimes added to the milk during the cheesemaking process or rubbed onto the cheese’s surface. Sage adds depth and balances the mildness of thistle rennet.

Lavender (Lavandula spp.)

Found especially around Siena, lavender is used sparingly to add a subtle, floral aroma that pairs beautifully with the softer textures of thistle-based cheese.

Fennel (Foeniculum vulgare)  

Fennel seeds or wild fennel are added for a sweet, licorice-like note. This herb is especially popular in the Maremma area, where it’s sometimes infused directly into the cheese.

Popular Thistle-Rennet Cheeses in Siena and Florence

While we are in Siena and Florence and other ancient towns of Tuscany on our 2025 trip (register here), we’ll have the opportunity to sample some of the region’s specially made local cheeses. Tuscany boasts an array of cheeses, many of which are made with thistle rennet. Though some thistle cheeses are relatively unknown outside Italy, several varieties have garnered a following among both locals and visitors to Tuscany. Here are a few beloved options from Siena and Florence:

• Pecorino Toscano: While Pecorino Toscano is typically made with sheep’s milk and can be produced with animal rennet, some artisanal versions use thistle rennet. This variety is especially popular in Siena, where cheesemakers create Pecorino Toscano with a more delicate, grassy flavor that’s less intense than the rennet-based versions. Aged varieties develop a firmer texture and pair well with local honeys and jams.
• Marzolino di Lucardo: Originally from the village of Lucardo near Florence, Marzolino is a mild, creamy cheese traditionally made with thistle rennet in the spring when the thistles bloom. The young cheese is soft with a slightly floral aroma. Often flavored with olive oil and rosemary, Marzolino has a delicate balance that pairs well with local Chianti wines.
• Cacio di Fossa: While not exclusively Tuscan, this cheese is loved in Siena and Florence. Traditionally aged underground in pits or fosse, Cacio di Fossa is sometimes made with thistle rennet, which imparts a lighter flavor to this otherwise intense cheese. The unique aging process adds earthy, nutty notes, and the thistle rennet version offers a subtler aroma.

Enjoy Tuscan Cheeses with these Local Wines

Definitely try your cheeses with wines!

Thistle-based cheeses from Tuscany are versatile, with flavors that can range from mild and grassy to nutty and herbaceous. Locals enjoy these cheeses on their own, with a drizzle of honey or fig jam, or paired with crusty Tuscan bread. When it comes to wine, thistle-rennet cheeses pair well with some of the region’s best-known wines:

• Chianti Classico: This red wine is a classic pairing for Pecorino Toscano. Its fruity notes bring out the sweetness in the cheese, while its acidity balances the creaminess.
• Vin Santo: Often paired with the region’s baked biscotti or with Marzolino di Lucardo, Vin Santo’s slight sweetness enhances the floral notes imparted by the thistle.
• Vernaccia di San Gimignano: This white wine from the San Gimignano region pairs excellently with thistle-rennet cheeses. Its crispness and mineral undertones work well with the herbal qualities of the cheese, creating a refreshing contrast.

Herbal Tuscany 2025

As of late October 2024, our Herbal Tuscany 2025 trip has room for more participants and you are invited to join us. We will be a group of herbie-and-foodie loving travelers who are eager to explore all Tuscany has to offer, led and curated by our co-hosts Richard Liebmann, former executive director of United Plant Savers and me, herbalist and author Holly Bellebuono.

Our adventure will include hot springs, botanical gardens, ancient herb gardens, essential oil farms and production sites, palace gardens and grottoes, Etruscan tunnels and wine tastings, and much more especially around Florence, Siena, Chianti, Montepulciano, and Assisi. Go here for more details and to register.