There are more than two hundred different species of truffles known today. However, only two are considered culinary treasures:Â Â
- White Truffle (Tuber magnatum)
- Black Winter Truffle (Tuber melanosporum)
Truffle cultivation is relatively modern in terms of agricultural practices, despite truffles themselves having been valued as a delicacy since ancient times, mentioned by Classical authors such as Pliny the Elder. However, they were only harvested from the wild, with no known cultivation methods.
From the Classical period right through to the 19th century truffles continued to be foraged from forests throughout Europe. Over time the demand for truffles grew among the European nobility and bourgeoisie. As demand for truffles grew so too did the desire to find a way to cultivate them.Â
Notably, as early as 1808, successful attempts to cultivate truffles were made. It was well known that truffles grew among the roots of certain trees. Inspired by this, Joseph Talon from Apt in the Vaucluse department of southern France, undertook a pioneering experiment. He transplanted seedlings from beneath oak trees, which were recognized for hosting truffles in their root systems. This method, though primitive, laid the groundwork for what would become a more systematic approach to truffle farming.
It wasn't until the 20th century that the science behind truffle cultivation began to unfold with techniques to inoculate tree roots with truffle spores in a nursery context. This innovation significantly improved the success rate of truffle production and the idea of the truffle plantation was born. This technique, first developed in France, spread in Europe then across the world to the United States, Australia, New Zealand and beyond.
Truffles are a type of underground mushroom known as the fruiting bodies of subterranean fungi, from the genus Tuber. They develop through a symbiotic relationship with the roots of certain trees like oaks and hazelnuts, forming a structure called a mycorrhiza.Â
In this relationship, truffles help the tree absorb water and nutrients more effectively, while the tree provides the fungus with sugars from photosynthesis. This nutrient exchange is vital for the growth and health of both the tree and the truffle.Â
The mycelium of the truffle extends through the soil, connecting with a network of tree roots to gather nutrients over a wide area. Under the right conditions, the mycelium aggregates and starts to form truffles, typically 10-30 cm below the soil surface.Â
Various factors such as soil chemistry, temperature, and moisture influence this process. Mature truffles contain spores that need to be dispersed to new locations for the cycle of growth to continue. In Europe, animals like wild boars and rodents are attracted to the truffles' strong smell, eat them, and then help spread the spores through their faeces.Â
In Australia, several native animal species are similarly attracted to the aroma of truffles. Notably, marsupials such as bandicoots and potoroos have been observed to seek out and consume truffles. Like the wild boars and rodents of Europe, these animals play a crucial role in the ecosystem by dispersing truffle spores, aiding in the propagation of truffle fungi.Â
Perhaps the most important thing to note is that the development of truffles is highly sensitive to specific environmental conditions, making their cultivation challenging and restricting natural growth to certain areas.
Truffles are cultivated through a careful process. Here’s a brief overview:
Choosing the Right Environment: Truffles require specific soil conditions and climates to thrive. The soil must be well-drained, with a high lime content, and the climate should have cold winters and hot summers with adequate rainfall. The ideal environments are to be found in regions like western, central and southern Europe, although truffle cultivation has spread to other parts of the world including, notably, Australia, New Zealand, Chile, Argentina and the United States, which have also been found to have the soil and climate conditions.
Selecting and Preparing Host Trees: Truffles are mycorrhizal fungi, meaning they form symbiotic associations with the roots of certain trees. The most common host trees are oaks (robur - English and ilex - French), and hazelnuts. These trees are inoculated with truffle spores before being planted. Seedlings are often kept in a nursery for 1 to 2 years before planting.
Soil Preparation: Soil preparation begins by testing the soil's pH, as truffles thrive in alkaline conditions, ideally between pH 7.5 and 8.5. Often the soil needs to be supplemented with lime to achieve the desired pH level. Truffles also require well-drained soil, so soil structure often needs to be enhanced by incorporating dolomite, and other soil additives. Once soils have been modified to optimal conditions they generally need a further year to settle prior to planting trees.
Truffle soils must be highly friable (soil that is easily broken down into small fragments) and well-structured, encompassing a wide variety of particle sizes. Optimal soils are loamy, and tend to feature balanced proportions of sand, silt, and clay, which improves drainage.
Planting and Maintenance: The inoculated trees are planted in the prepared soil. Consistent rainfall in summer and attentive soil management are crucial. In areas without consistent natural rainfall during dry periods, irrigation may also be necessary.
In maintaining soil health, biochar has emerged, in recent years, as a kind of "superfood" for soil.
Biochar, a portmanteau, combining the words biomass and charcoal. Resembling a kind of carbonised powder, this seemingly anodyne substance is proving to be something of a gamechanger in the cultivation of truffles.
Biochar, produced from organic materials like wood waste through pyrolysis, has proven to be a very effective additive in the cultivation of Tuber melanosporum.
Essentially, biochar improves soil structure by enhancing porosity and aeration crucial for the development of truffle mycelium. Its high water retention capabilities maintain optimal soil moisture essential for truffle growth, while its alkaline nature helps adjust soil pH to levels favorable for truffles, which prefer slightly alkaline conditions.
Biochar also boosts nutrient retention, providing a slow release of nutrients to truffle mycelium and supports beneficial soil microbes that assist in nutrient cycling and disease protection. Furthermore, its ability to sequester carbon for long periods not only makes it an environmentally sustainable choice but also helps maintain long-term soil fertility, essential for truffle cultivation.
Monitoring Growth: The growth of truffles is monitored over several years, as it can take 4 to 8 years for the first truffles to appear after the trees are planted. During this time, farmers use specially trained dogs to sniff out when truffles are ripe.
Researchers warn that climate change could decimate Europe’s truffle industry by the century's end.
A 2018 joint study by two researchers, Paul Thomas from the University of Stirling and Ulf Büntgen from the University of Cambridge, titled “A risk assessment of Europe’s black truffle sector under predicted climate change” and published in the Science of the Total Environment, highlights some concerning projections. “According to our research, under the most probable scenario of climate change, we anticipate a reduction in European truffle production of 78 to 100 percent from 2071 to 2100,” said Paul Thomas, the study's lead author. As noted by Modern Farmer, truffles are notoriously challenging to farm, with most being harvested from the wild, making them particularly vulnerable to weather conditions.
The prognosis worsens when considering additional climate factors like heatwaves, wildfires, droughts, pests, and diseases. “These elements could precipitate the industry's decline even before 2071,” Thomas added. “The loss of this industry, valued at hundreds of millions of pounds, could have a far greater socio-economic impact, considering its integral role in local culture and history.”
Thomas's team reached these conclusions after examining 36 years of truffle production data from France, Spain, and Italy and correlating these figures with historical weather data and future projections using advanced climate models.
These alarming findings have spurred calls for immediate conservation efforts to protect this iconic species. Thomas suggests that expanding truffle cultivation into areas with potentially more favourable future climates could be a solution. He also recommends adopting agricultural practices such as using mulching materials and modifying cultivation techniques to stabilise soil temperatures and retain moisture. Addressing the broader issue of climate change remains a global challenge, one that the world has struggled to effectively manage thus far.
In the last 30 years the truffle industry has been beset by a few scandals. One in particular is worth attention - the shadowy transnational trade of Chinese truffles. Much less known compared to their European or Australian counterparts, Chinese truffles (Tuber indicum and Tuber himalayensis) - originate from the wilds and farms of regions like Sichuan, Tibet, and Yunnan. Chinese truffles, while offering a more accessible and affordable option for some, do not match the quality or the prestige of French, Spanish, Italian or indeed Australian Tuber melanosporum in terms of quality, resulting in their much lower price. Himalayensis, especially, is often confused for Tuber melanosporum due to their similar appearances, and neither Chinese variants have the rich intoxicating aroma of genuine Tuber melanosporum. The real problem for truffle buyers is when they are mixed with genuine melanosporum truffles or used in products enhanced with synthetic truffle oil (2,4-dithiapentane), detecting them becomes a challenge.
Ideally, it’s best to use a truffle as soon as you can after receiving it. However, if you do need to store your truffle, it's best to do so in an airtight container placed in the lower section of your refrigerator. Ideally, using truffles within 2-4 days after they are harvested ensures minimal loss of flavour and aroma. This timeframe is perfect for infusing truffles with foods like butter, eggs, cheese and meats. If the truffle is slightly older when you receive it, definitely use it quickly.Â
If you don’t wish to store your truffles with other food items you should wrap the truffles in fresh paper towels to absorb any moisture and maintain dryness. Place the wrapped truffles in a sealed container and store them in your refrigerator. If you don't plan to use the truffles within 24 hours, remember to check them daily and replace the paper towels with new ones each day to prevent moisture buildup and potential mould growth if not changed every 12 to 24 hours.
What about the question of whether or not to store truffles in rice? While some like to store truffles in rice, and yes, it does impart a lovely scent to rice, it is important to know that rice actually extracts moisture from truffles very quickly, causing them to become dry.
To gain the most from a black truffle, minimal preparation is required. Truffles should be used liberally to enhance your dishes. Remember, it's better to enjoy a dining experience in which the truffle is the star of the show, than it being muted and playing "second fiddle."
Here are some tips to maximise their impact in your dishes:
Slice: Use a Truffle slicer - a specialised tool designed for slicing truffles into thin, uniform slices. The sharp stainless steel blade is adjustable, allowing you to set the thickness of the slices according to your preference.
Microplane: The Microplane has made big inroads in the culinary world because of its ability to shave a truffle into delicate "wool" like shavings. The Microplane creates tiny, wispy curls which unfurl exposing more of the truffle's surface area, releasing the truffle's aroma fully.
Infusing: Enhance butter by infusing it with truffle gratings using a Microplane. Truffle butter is a versatile ingredient, adding depth to risottos, and pastas. See recipe below.
Black Truffle Butter
Ingredients:
250g high quality unsalted butter (Gippsland Jersey, Pepe Saya, Échiré etc)
2 tablespoons black truffle, grated on a Microplane
2 teaspoons Olsson's Sea Salt or Maldon Sea Salt
Method:
- Allow butter to come to room temperature.Â
- Add all ingredients to a glass bowl and mash together.
- Remove butter mixture from bowl and lay the butter in a log shape on plastic wrap or baking paper.Â
- Roll tightly into a log.
- Store in the refrigerator and consume within 2 weeks or place in the freezer.
Finishing Touches: Add truffle slices towards the end of cooking to preserve their flavour. They pair wonderfully with creamy or buttery dishes, such as pasta, risotto, scrambled eggs, or mashed potatoes.
Pairing with Complementary Ingredients: Black truffles pair excellently with mild ingredients that don't overpower their complex flavour. Ingredients like Parmigiano Reggiano, cream, leeks, lobster and scallops. When using with chicken it is best to make a log of truffle compound butter, cutting the butter into disks and place thin truffle slices on the butter disks which are then placed liberally under the skin before roasting.
Black truffles can transform ordinary meals into extraordinary culinary experiences. By selecting, storing, and incorporating truffles into your dishes correctly, you can unlock their full potential and enjoy the depth and complexity they bring to your table. Whether you’re a seasoned chef or an enthusiastic home cook, experimenting with truffles will undoubtedly add great flair to your cooking repertoire.
What dish will you elevate with the magic of truffles?
The overall effect of cooking truffles in cream and cheese based pasta sauces is the development of a rich, complex flavour profile that is truly greater than the sum of its parts, creating a delightful sensory experience like no other.Â
When truffles are cooked with dairy, for example, a fascinating interplay of chemical reactions occurs between the volatile organic compounds (VOCs) in the truffles and the organic compounds in the milk. Essentially, cooking forces pH changes due to the truffle's acidic content, altering the stability and release of VOCs. And of course….cooking does tend to make some volatile compounds more prominent while diminishing others, based on their thermal stability and volatility, but that’s another discussion. Overall, though, the basic takeaway point is this: when truffle is combined with dairy this combination both enhances existing flavours and aromas and creates wonderful new ones.Â
Here's a brief breakdown of what happens chemically:
Protein and Fat Interactions: The proteins in milk, primarily casein and whey proteins, bind with some of the VOCs, particularly the sulphur compounds, altering their volatility and impacting the perception of their aromas, giving the truffle scent different nuances.
Milk fats dissolve and absorb hydrocarbons, terpenes, and sulphur compounds from the truffles, helping to retain and slowly release aromatic molecules during and after cooking, enhancing the overall flavour experience.
Carbohydrate Reactions: The primary carbohydrate in milk is lactose which does not itself react extensively with truffle VOCs. However, the cooking process does induce certain non-enzymatic reactions when reducing sugars react with the amino acids in truffle. This results in the release of complex and rich flavours and aromas.
Enzymatic Reactions: Milk contains enzymes like lipases and proteases which break down fats and proteins respectively. When truffles are introduced, these enzymes modify the VOCs through oxidation or hydrolysis, which alters sulphur compounds, modifying the truffle's characteristic aroma, and likewise resulting in the release of complex and rich flavours and aromas.
Creation of New Compounds: When truffle VOCs and milk compounds are subjected to heat, new compounds form through reactions like esterification. Esterification is a chemical reaction where an acid and an alcohol combine to form a compound called an ester. In terms of cooking truffles, this reaction occurs when the natural acids in truffles react with the alcohol present in milk due to fermentation processes, forming new esters that have unique and wonderful new flavours and aromas.
White truffles, celebrated for their intoxicating aroma and subtle flavour, are best enjoyed both shaved fresh sitting atop dishes and also incorporated into sauces and slightly warmed. This advice is contrary to what you might read elsewhere, but in our section above on the interaction between truffles and lactic acid we outline why this is a culinary myth worth debunking. Garnishing dishes like pasta, risotto, or eggs with shaved truffles just before serving also optimally releases their aroma, warmed slightly by the dish's heat.
The common belief that all white truffles originate from the northern Italian city of Alba is a misconception. In truth, Alba, located in the province of Cuneo, Piedmont, does not directly produce truffles as they do not grow within town limits. While some truffles are found in the surrounding regions, the dense vineyards around Alba aren't conducive to truffle growth, which typically requires forested areas.
Truffles are indeed found throughout Piedmont, but the proportion of Europe's white truffles that come from near Alba is likely under 5%. Contrary to popular belief, Alba truffles are not the only 'authentic' white truffles; others are not 'imitations'. In truth high-quality truffles actually come from the Balkan Peninsula - especially the Istrian region of Croatia or the large oak forests of Southern Hungary, and Serbia — regions far from Alba.Â
The term "Alba truffles" became popular due to historical marketing efforts by Giacomo Morra, who branded the Alba white truffle and promoted it globally by sending them as gifts to celebrities. This has led to a long-standing misconception that has benefited Italian truffle companies, promoting the idea that the best truffles can only come from Italy. However, many truffles found in Eastern Europe are often sold as Italian, a practice known within the industry and facilitated by historical undervaluation in these regions.
The evolving truffle market is shifting towards transparency, with suppliers eager to disclose the true origins of their truffles. This change is supported by chefs and diners who value authenticity and quality over geographic origin. In summary, the magic of white truffles isn't lost by knowing their real origins; if anything, it enhances the appreciation of these exquisite fungi, whether they come from Italy, Croatia, Hungary, Serbia, Northern Greece or beyond.