The Cheesy Worm: What's Inside Your Cheese?

The idea of eating cheese infested with worms may seem stomach-churning to some, but for the people of Sardinia, it is a delicacy. This cheese, called casu marzu, is made from sheep's milk and contains live insect larvae (maggots). The larvae are introduced to the cheese deliberately, promoting an advanced level of fermentation and breaking down the cheese's fats. While casu marzu has been deemed dangerous and illegal to sell, it remains a beloved part of Sardinian food culture, with locals consuming it for centuries.

Casu marzu, a Sardinian cheese with live maggots, is considered an aphrodisiac

Casu marzu, a traditional Sardinian sheep milk cheese, is known for containing live insect larvae or maggots. The cheese is derived from pecorino and is produced by leaving whole pecorino cheeses outside with part of the rind removed, allowing female Piophila casei cheese flies to lay their eggs in the cheese. A single female P. casei can lay upwards of 500 eggs at once. Once the eggs hatch, the resulting larvae feed on the cheese, breaking down its fats and creating a very soft texture. A typical casu marzu wheel will contain thousands of these maggots, which appear as translucent white worms about 8mm long.

The process of making casu marzu is a delicate one. The ideal milk for casu marzu is collected towards the end of June, as the effects of the reproductive cycle of sheep on their lactation are considered optimal at this time. Local fermentation traditions also associate higher quality casu marzu with exposure to a warm sirocco wind, which is believed to further soften the cheese and encourage maggot activity. The overall fermentation process takes about three months.

Casu marzu is considered a delicacy in Sardinia, with a strong, rare taste that is revered by locals. It is believed to be an aphrodisiac and is deeply rooted in the island's superstition and mysticism. The process of making casu marzu is also steeped in tradition, with historical accounts tracing its origins back to the time when Sardinia was a province of the Roman Empire. Despite its cultural significance, casu marzu has faced legal challenges due to health concerns associated with the presence of live maggots. Italian authorities have banned its sale, and it is also prohibited in the European Union due to food safety regulations. However, the production and consumption of casu marzu persist, with some Sardinians even resorting to the black market to obtain this forbidden treat.

The consumption of casu marzu is not for the faint of heart. When the cheese is cut open, the maggots inside writhe frantically, and some diners hold their hands above the sandwich to prevent the maggots from leaping. While some people choose to avoid ingesting the maggots, others embrace the unique experience. Those who wish to avoid eating the larvae may place the cheese in a sealed paper bag. As the maggots inside the bag become starved for oxygen, they writhe and jump, creating a "pitter-patter" sound. Once the sounds stop, indicating that the maggots are dead, the cheese can be consumed without the live larvae.

Despite the concerns surrounding the safety of consuming casu marzu, there have been no documented cases of health issues specifically linked to the cheese. However, it is important to note that the larvae can potentially survive the stomach acid and remain in the intestine, leading to a condition called pseudomyiasis. Additionally, the larvae may carry harmful microorganisms that could cause infections.

The dangers of eating cheese with worms

Cheese with worms, or more specifically, casu martzu, is a traditional Sardinian sheep milk cheese that contains live insect larvae, or maggots. The larvae are introduced to the cheese deliberately, promoting an advanced level of fermentation and breaking down the cheese's fats. While this may be a delicacy for some, there are several dangers associated with consuming cheese containing live worms.

Firstly, there is a risk of enteric pseudomyiasis, a condition where the larvae survive in the intestine. Although no cases have been directly linked to casu martzu, the possibility exists, and it is a serious health concern. Additionally, these larvae can carry harmful microorganisms that may lead to infections. The potential for infection is heightened by the fact that the larvae can launch themselves up to 15 centimetres when disturbed, increasing the risk of them coming into contact with the skin, eyes, or mouth.

The consumption of casu martzu is illegal in Italy and the European Union due to these health risks. Offenders face heavy fines, and the cheese is banned from commercial sale. However, this has not stopped the production and consumption of this cheese, with some Sardinians continuing to eat it and even considering it a revered part of their cultural heritage.

In conclusion, while casu martzu may be a traditional delicacy for some, the dangers of consuming cheese with worms are significant. The potential health risks, including enteric pseudomyiasis and infections, along with the possibility of food contamination and psychological distress, outweigh any perceived benefits. It is important to approach this food with caution and be fully informed of the risks before considering consumption.

How to eat cheese with worms

Casu martzu, or the Sardinian "rotten cheese", is a traditional sheep milk cheese from Sardinia that contains live insect larvae, or maggots. The larvae are deliberately introduced to the cheese to promote an advanced level of fermentation, breaking down the cheese's fats. The translucent white worms are about 8mm long and, when the cheese is ready for consumption, there can be thousands of them.

If you are brave enough to try this delicacy, there are a few things to keep in mind. Firstly, it is considered unsafe to eat the cheese if the maggots are dead, so only eat it if they are still alive (or if they have been killed by refrigeration). Secondly, the larvae can launch themselves up to 15cm when disturbed, so it is recommended to hold your hands above the cheese to prevent them from leaping.

If you do not want to ingest the maggots, you can place the cheese in a sealed paper bag. The maggots will writhe and jump in the bag, creating a "pitter-patter" sound. Once the sounds stop, the maggots are dead and you can eat the cheese.

When eating casu martzu, it is often cut into thin strips and spread on moistened Sardinian flatbread (pane carasau). It is typically served with a strong red wine like cannonau.

Please note that casu martzu is banned in Italy and the European Union due to safety concerns, and it may be difficult to obtain outside of Sardinia. There are also health risks associated with consuming the cheese, as the larvae can survive in the intestine and cause pseudomyiasis.

The history of wormy Sardinian cheese

Also known as Casu Marzu, this Sardinian sheep milk cheese is famous for containing live insect larvae, or maggots. The name Casu Marzu literally translates to 'rotten cheese' in Sardinian. It is derived from pecorino cheese, which has been produced in Sardinia since the Bronze Age.

Casu Marzu is made by deliberately introducing the larvae of the cheese fly (Piophilidae family) to the cheese. The female P. casei lays her eggs in the cheese, and when these hatch, the resulting maggots begin to eat through the cheese, breaking down its fats. This process softens the cheese and promotes an advanced level of fermentation. The texture of the cheese becomes very soft, with a liquid called "lagrima" (meaning "teardrop" in Sardinian) seeping out.

The overall fermentation process takes three months. The cheese is considered unsafe to eat when the maggots have died, so it is usually consumed when they are still alive. The maggots can launch themselves up to 15 centimetres when disturbed, so diners hold their hands above the sandwich to prevent them from leaping. Those who do not wish to ingest the maggots place the cheese in a sealed paper bag. The maggots, deprived of oxygen, then writhe and jump in the bag, creating a "pitter-patter" sound. When the sounds stop, the maggots are dead, and the cheese can be eaten.

Casu Marzu is considered a delicacy in Sardinia, and aficionados believe it to be an aphrodisiac. It is also believed to be safe to eat, despite the potential health risks associated with consuming live larvae. The cheese has been banned in Italy and the European Union due to food safety regulations, but it is still produced and consumed illegally, with some even attempting to have it declared a traditional food.

The origins of Casu Marzu are unclear, but it is believed to have been consumed for centuries, possibly dating back to the time of the Roman Empire. Local gastronome Giovanni Fancello traced the history of Sardinian cuisine to this period, noting that worm-eating was mentioned by Pliny the Elder and Aristotle. The cheese gained infamy when it was featured on a cooking show by Gordon Ramsay in 2011, and it has since become a notorious delicacy among tourists.

How to make cheese with worms

Casu marzu, also known as the "maggot cheese", is a traditional Sardinian sheep milk cheese that contains live insect larvae. Here is a step-by-step guide on how to make this infamous cheese:

Step 1: Prepare the Sheep Milk

Start by boiling sheep's milk at 35°C. Once the milk reaches the desired temperature, add rennet, which will cause the liquid to coagulate and eventually curdle. This process should take around 25 minutes.

Step 2: Moulding and Brining

Next, pour the curdled milk into moulds and let it set for 24 hours. After this, transfer the cheese into a brine solution for further curing.

Step 3: Introduce the Maggots

Now comes the crucial step that sets casu marzu apart: introducing the maggots. Leave the cheese in the open air with part of the rind removed. This will invite female cheese flies (Piophila casei) to lay their eggs in the cheese. A single female fly can lay up to 500 eggs at once.

Step 4: Maggot Maturation

The eggs will hatch into larvae, which will then begin to eat and digest the cheese. The acid from the maggots' digestive system breaks down the cheese's fats, resulting in a very soft texture. The ideal time to consume the cheese is when it contains thousands of these maggots, which is usually after a few months.

Step 5: Consumption

Casu marzu is often consumed with the maggots still alive, as this is considered a part of the cultural tradition in Sardinia. The cheese is typically cut into thin strips and spread on Sardinian flatbread, paired with a strong red wine. However, due to health concerns, it is important to note that the cheese has been banned in many countries.

The larvae can jump up to 15 centimetres when disturbed, so diners hold their hands above the sandwich to prevent the maggots from leaping. If you wish to avoid ingesting the maggots, you can place the cheese in a sealed paper bag. The maggots, deprived of oxygen, will eventually die, and the cheese can then be eaten.

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