Auricularia auricula-judae

What You Should Know

Wood Ear Mushroom, scientific name Auricularia auricula-judae, is a type of edible jelly mushroom with an ear-shaped form that grows on trees, especially elder trees. It has a purplish-grayish brown to dingy brown color, is smooth and wrinkled in the center, and has fine hairs. It grows throughout the year in Europe and America and is commonly used in Asian soups. The species was once thought to be cosmopolitan, but molecular research showed it to be at least seven different species worldwide.

The European species is now referred to as Auricularia auricula-judae, while the commercially grown Chinese and East Asian species is called Auricularia heimuer (black wood ear). The name Judas's Ear comes from a legend linking the ear-like shape of the mushroom to the apostle Judas who betrayed Jesus.

Other names: Wood Ear Mushroom, Judas's Ear, Jelly Ear Mushroom, Czech Republic (Jidášovo ucho), Spain (Oreja de Judas).

Auricularia auricula-judae Identification

1. Fruiting Body

   The fruit body of A. auricula-judae is normally up to 3.5 inches (9 cm) across and up to 0.12 inches(3 mm) thick. It is often reminiscent of a floppy ear, but can also be cup-shaped. It is attached to the substrate laterally and sometimes by a very short stem. Fruit bodies have a tough, gelatinous, elastic texture when fresh, but dry hard and brittle. The upper surface is a reddish-tan-brown with a purplish tint and finely pilose (covered in tiny, grey, downy hairs). It can be smooth, as is typical of younger specimens, or undulating with folds and wrinkles. The colour becomes darker with age. The under surface is a lighter grey-brown and smooth, sometimes folded or wrinkled, and may have "veins", making it appear even more ear-like.

2. Flesh

   The flesh is thin, dense, cartilaginous, translucent, without a pronounced smell.

3. Spore Print

   White.

4. Habitat

   Judas's Ear mushrooms grow on the wood of old trees, deciduous species, and shrubs, mostly found on beech, ash, spindle, or Acer pseudoplatanus trees. Although, it has been found on various types of trees in India's Western Ghats and in rainforests in Australia. It grows in a chaotic way, attached to dead or decaying branches and can form huge clusters in wet conditions. The mushroom can have various shapes, colors, and sizes and lives as a saprophyte or minor parasite causing white rot. It is found in groups or as single mushrooms and is a very prolific species, producing hundreds of thousands of spores even after it has dried up. It grows all year-round on all continents in both temperate and sub-tropical climates.

5. Microscopic Features

   Spores 12–14 x 4–5.5 µm; allantoid; smooth; hyaline in KOH. Basidia 65–75 x 4–5 µm; cylindric; filled with semi-refractive oil droplets; transversely 3-septate; difficult to isolate in a mount due to a gelatinous matrix; sterigmata difficult to locate. Flesh composed of scattered, poorly defined, gelatinized hyphae 2–3 µm wide; medullary zone not differentiated. Abhymenial surface with projecting hyaline hairs 40–125 x 7.5–12.5 µm; cylindric-fusiform; walls 2–3 µm thick; smooth; hyaline to golden in KOH.

Auricularia auricula-judae Look-Alikes

1. Auricularia cerrina

   Recently described on oak (Quercus) from the Czech Republic, but probably more widespread in southern Europe. It can be distinguished by its dark gray to almost black fruit bodies.

2. Auricularia heimuer

   Very similar and has long been confused with A. auricula-judae. It can be distinguished microscopically by its shorter basidia and shorter spores (11–13 × 4–5 μm).

3. Auricularia angiospermarum

   Similar, but has shorter basidia and spores (13–15 × 4.8–5.5 μm).

Auricularia auricula-judae Health Benefits

Wood ear mushrooms have multiple health benefits including:

1. Antibacterial properties

2. Managing diabetes

3. Antitumor properties (due to active component diazane)

4. Lowering cholesterol

5. Anticoagulation and antioxidant properties

6. Radioprotective properties (due to melanin pigments)

7. Anti-quorum-sensing and immunomodulatory properties

8. Polysaccharide as an oral drug delivery

9. Antiviral properties (due to sulfated polysaccharide)

10. Treating anemia and preventing obesity

11. Beneficial for heart health and has anti-inflammatory properties

12. Used in herbal medicine for throat and eye ailments

However, wood ear mushrooms may negatively impact fertility. Pregnant and lactating women and those trying to conceive may want to avoid it.

Auricularia auricula-judae Uses

Culinary use

Though edible, it is not held in high culinary regard because of its jelly-like texture. It has been likened to "eating an Indian rubber with bones in it", while in 19th-century Britain, it was said that "it has never been regarded here as an edible fungus". The species is said to be commonly consumed in Poland.

It has a mild flavor, which may be considered bland. It can be dried and rehydrated, sometimes swelling to 3 – 4 times in size. The species is not edible when raw, needing to be cooked thoroughly.

Fresh mushrooms contain about 90% moisture. Dried specimens may be ground up into a powder and used to absorb excess liquid in soups and stews, as it rehydrates into tiny fragments.

Medicinal use

It was used as a poultice to treat inflammations of the eye, as well as a palliative for throat problems. The 16th-century herbalist John Gerard, writing in 1597, recommended A. auricula-judae for a very specific use. He recommends the preparation of a liquid extract by boiling the fruit bodies in milk, or else leaving them steeped in beer, which would then be sipped slowly to cure a sore throat. The resultant broth was probably not dissimilar to the Chinese soups that use Auricularia cornea.

Carolus Clusius, writing in 1601, also said that the species could be gargled to cure a sore throat.

The species also saw use as an astringent due to its ability to absorb water. There are recorded medicinal usages from Scotland, where it was again used as a gargle for sore throats, and from Ireland, where, in an attempt to cure jaundice, it was boiled in milk. The medicinal use of A. auricula-judae continued until at least 1860, when it was still sold at Covent Garden; at the time, it was not considered edible in the United Kingdom.

Pharmacology

Numerous research papers have been published on possible medicinal applications of a fungus said to be "Auricularia auricula-judae" or "Auricularia auricula", but it is not always clear which species was used for research. At least some papers published from Asia have used locally-sourced material and probably refer to Auricularia heimuer or other regional species known to have potential pharmaceutical applications.

Auricularia auricula-judae Cultivation Notes

Steps to grow a Auricularia auricula-judae are as follows:

1. Obtain tissue culture of the mushroom to produce grain spawn.

2. Choose a suitable fruiting method from log method, artificial log method, and Poly bag method.

3. Select an appropriate substrate for fruiting body production such as dead or dying branches of trees, main trunk, decaying logs, etc.

4. Incubate the substrate with the grain spawn for several weeks.

5. Place the incubated substrate in a suitable environment with proper temperature, humidity, and light conditions.

6. Harvest the mature fruiting bodies and repeat the process to continue cultivation.

Note: Ensure that the fruiting environment is maintained within the temperate and subtropical zones as Auricularia spp. is widespread in these zones worldwide.

Risks and Side Effects for Wood Ear Mushrooms

Rehydrated wood ear mushrooms must be used within one day. Long-soaked wood ear mushrooms or black fungus might be poisonous and harmful to the body.

Additionally, those with an allergy should not consume wood ear mushrooms to avoid food allergy symptoms like nausea, itching, swelling, and hives. In some cases, wood ear mushrooms may act as an anticoagulant and prevent blood from clotting.

Wood Ear Mushroom vs. Black Fungus

Nutritionally, these mushrooms are extremely similar, offering great sources of protein, good carbohydrates, B vitamins, and numerous minerals. Whatever slight differences in nutrients may have been negligible, and this is also true for their health benefits. The health benefits of most medicinal mushroom species are extremely similar.

Wood ear mushrooms grow wild on elder trees and black fungus, sometimes called cloud ear, grows on other trees, but both are found in temperate, sub-tropical forests. The wood ear is a thicker, larger fungi that needs to be cooked longer than black fungus. The smaller, daintier black fungus can be prepared faster.

As for visual differences, Wood Ear mushrooms are thin, curled, light- or dark-brown mushrooms that resemble the ears of the elderly, hence their name. On the other hand, Black Fungus is slightly similar in shape, though not as ear-shaped, but is less fleshy in appearance and much darker in color.

Wood Ear Mushroom vs. Shiitake

Shiitake mushrooms can stand in for the chewy texture of wood ears, although they lack the wood ear's thin, crinkly structure. Remember that shiitake mushrooms add a rich, earthy flavor to any dish, in comparison to the flavor-neutral character of wood ears.

Wood Ear Mushroom vs. Cloud Ear

Cloud ear is often confused with wood ear, a related fungus that also grows on trees. They are both dark-colored and shaped like an ear. Cloud ear is smaller and more tender than the wood ear mushroom, but the two types of fungi can generally be used interchangeably.

Eating Auricularia auricula-judae During Pregnancy

Jew's ear mushrooms, also known as wood ear mushrooms, are considered safe to eat for most people when properly prepared and cooked. However, it's always best to consult with your doctor or a qualified healthcare provider before consuming any new food, especially when you're pregnant. This is because some pregnant women may have dietary restrictions or may be advised to avoid certain types of foods for their own health or the health of their developing fetus.

Auricularia auricula-judae Nutrition Facts

The nutritional content of 100 g (3.5 oz) of dried fungus includes 370 kcal, 10.6 g of protein, 0.2 g of fat, 65 g of carbohydrate, 5.8 g ash, and 0.03% mg of carotene. Fresh mushrooms contain about 90% moisture.

Cooking and Storage Notes for Wood Ear Mushrooms

Cooking:

1. Soak dried wood ear mushrooms in warm water for 15-30 minutes until they are soft. Drain and rinse before using.

2. Add the rehydrated mushrooms to stir-fry dishes, soups, stews, or sauces for a crunchy texture and a mild, earthy flavor.

Storage:

1. Dried wood ear mushrooms can be stored in an airtight container for several months in a cool, dry place.

2. Fresh wood ear mushrooms should be stored in a paper bag in the refrigerator for up to one week. Avoid storing them in a plastic bag, as this can cause them to become slimy and spoil faster.

Recipe: Auricularia auricula-judae Salad

Ingredients

1. 4 cups rehydrated wood ears, trimmed and washed

2. 3 cloves of garlic, finely chopped

3. 1-2 fresh red chili peppers, deseeded and chopped (optional)

4. 1½ tablespoons Chinese black vinegar

5. 1 tablespoon light soy sauce

6. 1 teaspoon sugar

7. 1 teaspoon sesame oil

8. 1 tablespoon finely chopped scallions (and/or cilantro)

Instructions

1. In a medium-sized pot, cook the wood ears in boiling water for 3-4 minutes.

2. Drain and rinse under cold running water to cool them completely. Set aside and let any excess water drain off. You can also use a salad spinner to get rid of the excess water.

3. In a large bowl, mix together the garlic, peppers, vinegar, light soy sauce, sugar, and sesame oil until the sugar dissolves. Next, add the wood ear kmushrooms and mix well. Cover and let marinate in the refrigerator for 30 minutes.

4. Make sure to stir and mixture again before serving, as the sauce tends to settle to the bottom. Plate and garnish with the chopped scallion and/or cilantro.

5. Serve your Auricularia auricula-judae salad as a side dish or appetizer!

Recipe: Vietnamese Egg Meatloaf

Ingredients

1. 20 g wood ear mushrooms (~ a scant 1/2 cup)

2. 500 g ground pork

3. 200 g shrimp minced

4. 5 large eggs (3 whole, 2 separated into yolks and whites)

5. 200 g shallots diced (3-4 medium shallots)

6. 1 medium carrot shredded

7. 2-3 cloves garlic minced

8. 50 g mung bean noodles

9. 2 tbsp fish sauce

10. 1 tbsp sugar

11. 1 tsp salt

12. 1/2 tsp black pepper freshly ground

Instructions

1. Soak the wood ear mushrooms in warm water for 15-20 minutes, or until softened and pliable. Once the mushrooms are ready, chop them into thin slices, or mince them.

2. Soak mung bean noodles in cold water for 10-15 minutes. Once they're soft and flexible, cut them into approx. 5 cm (2 inch) pieces.

3. Combine all of the ingredients EXCEPT FOR the two reserved egg yolks in a large bowl. Mix thoroughly, ensuring that the eggs and egg whites are distributed evenly.

4. Line a large, flat pan with parchment paper. A brownie or cake pan works nicely, but anything that's not too deep and fits in a steamer will work. If you don't have parchment paper you can use aluminum foil or some vegetable oil to line the pan.

5. Spread the mixture in the pan. Smooth out the surface as much as you can.

6. Whisk the egg yolks with a pinch of salt. Pour them evenly over the surface of the meatloaf, tipping the pan to get the mixture to the edges if necessary.

7. Place the meatloaf in a steamer. Cover and steam for 20 minutes. You may need to adjust the cooking time if your pan is on the small side, as it will make the meatloaf thicker. If in doubt, check the internal temperature with a meat thermometer - it's done at 71°C (160°F).

8. When uncovering the finished meatloaf, take care to let condensation on the lid drip away from the egg mixture to avoid discoloring it (there's nothing dangerous with getting water on the top, but it's less attractive). Let the finished meatloaf sit for about 10-15 minutes before slicing and serving alone or with broken rice.

Recipe: Pork Belly with Bell peppers and Wood Ear Mushrooms

Ingredients

1. 1 pound pork belly, cut into half-inch slices

2. 1 cup dried wood ear mushrooms, soaked in cold water for 2 hours and chopped roughly

3. 1 bell pepper, cut into chunks

4. scant ¼ cup soy sauce

5. ¼ cup water

Instructions

1. Sear pork in a dry wok over medium-high heat until golden brown on all sides.

2. Then add the bell pepper and stir-fry for a couple of minutes. Add the soy sauce and mushrooms. Stir-fry for about 5 minutes to marry all the flavors.

3. Add ¼ cup water, cover, and simmer for 5-10 minutes over medium heat. Stir one last time and serve!

Recipe: One-Pot Vegan Mushroom Stroganoff

Ingredients

1. 1 tbsp oil

2. 6 oz cremini mushrooms - washed, trimmed, halved, and sliced

3. 1/2 cup shallots - finely minced

4. 3/4 cup mixed dried mushrooms

5. 1/2 tsp dried thyme leaves

6. 1/2 tsp black pepper - freshly ground (plus more for garnishing)

7. 1/4 tsp coarse salt

8. 4 cups vegetable broth

9. 4 cups wide pasta

10. 1 tbsp cornstarch

11. 1/4 tsp Maggi seasoning sauce

12. 1 tsp yellow mustard

13. 1/2 cup vegan sour cream

Instructions

1. Heat the oil in a heavy-bottomed pot or skillet over medium heat. Add the cremini mushrooms and shallots. Sauté until the shallots are translucent and softened, 5–7 minutes.

2. Add the rehydrated mushrooms, thyme, black pepper, and salt. Sauté for one minute. Add the pasta and the vegetable broth. Bring to a boil, then reduce the heat and simmer, covered, for 10 minutes, stirring occasionally. Uncover the pot and continue simmering until most of the liquid has been absorbed or reduced, and an additional 2–5 minutes. Stir frequently, scraping the bottom of the pan with a wooden spoon.

3. Remove from the heat and mix in the Maggi seasoning sauce, mustard, and sour cream. Taste for seasoning, adjusting if necessary. Serve immediately, sprinkled with fresh chives or parsley, nutritional yeast (if using), and more freshly ground black pepper.

Auricularia auricula-judae Taxonomy and Etymology

Auricularia auricula-judae, commonly known as Judas's ear, was first described as Tremella auricula by Carl Linnaeus and later redescribed by Bulliard as Tremella auricula-judae. In 1822, it was transferred to the Exidia genus as Exidia auricula-judae by Swedish mycologist Elias Magnus Fries. In 1888, the species was finally named Auricularia auricula-judae by Joseph Schröter, with the specific epithet "auricula-judae" meaning "ear of Judas".

Auricularia auricula-judae Synonyms and Varieties

• Tremella auricula-judae Bull., 1789

• Auricularia auricula (L.) Underw.

• Auricularia auricularis (Gray) G.W. Martin

• Auricularia lactea (Quél.) Bigeard & H. Guill.

• Auricularia sambuci Pers.

• Exidia auricula-judae (Bull.) Fr., 1822

• Gyraria auricularis Gray

• Hirneola auricula (L.) H. Karst.

• Hirneola auricula-judae (Bull.) Berk., 1860

• Hirneola auricularis (Gray) Donk

• Merulius auricula (L.) Roth

• Peziza auricula (L.) Lightf.

• Peziza auricula-judae (Bull.) Bull., 1791

• Tremella auricula L., 1753

• Tremella auricula-judae Bull.

• Auricularia auricula-judae f. auricula-judae (Bull.) Quél.

• Auricularia auricula-judae var. auricula-judae (Bull.) Quél.

• Auricularia auricula-judae var. lactea Quél.

• Auricularia auricula-judae var. lactea Quél., 1886

• Hirneola auricula-judae subsp. auricula-judae (Bull.) Berk., 1860

• Hirneola auricula-judae var. auricula-judae (Bull.) Berk.

• Hirneola auricula-judae var. lactea (Quél.) D.A. Reid

• Tremella auricula-judae var. caraganae Pers., 1801

Sources:

Photo 1 - Author: Dominicus Johannes Bergsma (Creative Commons Attribution-Share Alike 4.0 International)

Photo 2 - Author: Michel Langeveld (Creative Commons Attribution-Share Alike 4.0 International)

Photo 3 - Author: ronald_flipphi (Creative Commons Attribution-Share Alike 4.0 International)

Photo 4 - Author: Michel Langeveld (Creative Commons Attribution-Share Alike 4.0 International)

Photo 5 - Author: Stephen James McWilliam (Creative Commons Attribution 4.0 International)