Morels, raw (edible morels, round morels)

Morels are a very tasty genus of edible mushrooms, especially the edible morel or round morel .

Use in the kitchen:

Insects and dirt tend to collect in the coarsely wrinkled, light to dark brown cap, which resembles a sponge. Therefore, the cap of the morel is cut in half and washed thoroughly with water before use. A brush can also be useful here. The tender flesh of the morel gives soups and stews a nutty, caramel-like taste.

Morels are usually enjoyed pure, without much seasoning, just with a little salt and pepper. The hollow caps can also be stuffed, or you can cut them crosswise to create golden rings that you can fry. ² Dried morels should be soaked in water before use. To render the toxins contained in fresh morels harmless, they should be boiled for at least 20 minutes. Please put any leftovers in the fridge immediately and use them within 48 hours. When you first try to eat morels, make sure you only eat small amounts to minimize the risk of allergies.

Shopping:

Fresh morels are only available in season, most likely at weekly markets. You can find dried morels in many supermarkets, health food stores, Asian shops or online shops. Morels are among the most expensive edible mushrooms. Nevertheless, do not buy the cheapest products, but pay attention to quality. To save time, morels are often dried over a fire, which leaves a smoky taste and reduces the quality. A smell test can be helpful here. Unfortunately, there have also been cases where packages have contained morels (genus Helvella ) in addition to morels (genus Morchella ), which is dangerous. Even if some of the toxins contained are reduced during drying, morels are by no means an edible mushroom. ³

Found in the wild:

Morels are only available from wild stocks. They can be found in forest clearings, abandoned orchards and on pastures. ² They also grow on wood waste and are found in fire sites. They like to live together with ash and elm trees. Attempts to cultivate them have been made, but these have failed for industrial cultivation.

In many European countries, morels are protected species (D) and collecting them is therefore only permitted for personal use. There is often a quantity limit of 2 kg per person per day.

Storage:

Since fresh morels have a short shelf life, it is best to preserve them. Once cleaned, they can be packed in plastic bags and frozen. If well dried, they can be stored airtight and protected from sunlight for up to a year. To dry them, they can be cut in half lengthways and hung up in the room on a string.

Ingredients:

The dry mass of morels contains around 20% proteins and amino acids (arginine, lysine , glutamine). The rest consists mainly of fiber, some carbohydrates and hardly any fat. 100 g of morels contain 100% of the vitamin D content. It also contains B vitamins such as riboflavin (B ₂ ), niacin (ex. B ₃ ) and pyridoxine (B ₆ ). Minerals such as iron , copper , manganese , phosphorus , potassium and zinc are also present. See the ingredient tables at the end of this text.

Health aspects:

The polysaccharides (complex sugars) contained in morels are said to have immune-stimulating, immune-modulating and even tumor-inhibiting effects. ^8,9 The polysaccharides in morel mycelia are antioxidants (stronger than vitamin E). ¹⁰

Dangers/Intolerances:

If eaten raw, intolerances can occur, including symptoms of poisoning. Since morels contain the heat-labile toxin hydrazine, they must be cooked. Hydrazine is classified as probably carcinogenic. Morel syndrome occurs around 6-8 hours after eating raw morels. Vertigo, gait disturbances or visual disturbances are the symptoms, which disappear after around 24 hours. ⁴ Eating cooked morels in combination with alcohol can cause stomach upset. If the fruiting body shows rotten spots, these can also be poisonous. ⁵

If edible morels grow in old apple orchards where the insecticide lead arsenate was used, the mushrooms accumulate toxic lead and arsenic. This can lead to heavy metal poisoning. ⁶

Folk medicine

In traditional Chinese medicine, morels are used to treat digestive disorders, sputum and shortness of breath. ¹¹

Distribution:

Morels are found in Central Europe, North America (East and Midwest) and Brazil. The ecology of morels is highly controversial. Some Morchella species form symbiotic or endophytic relationships with trees, which varies across continents and regions. Others act as soil decomposers. Yellow morels are found primarily under deciduous trees, while black morels are found mostly in coniferous forests, on disturbed soils or in recently burned areas. ⁷

Cultivation, harvest:

Depending on the region, morels grow from March to May (May mushroom). They often only appear for a few days, for example after a warm spring rain.

Danger of confusion:

Morels can only be easily confused with one poisonous type of mushroom, the morels. One of these is the poisonous spring morel ( Gyromitra esculenta ), whose cap is twisted like a brain. The edible morel has a honeycomb-shaped chambered cap.

Sometimes morels are confused with edible verpel species (eg foxglove verpel, wrinkled verpel), although the cap is actually easy to distinguish. ¹ Verpels are not declared as edible mushrooms. They are protected and lack the typical morel aroma, which is why collecting them is not recommended.

General information:

The genus morels ( Morchella ) belongs to the Ascomycota. The spores have tubular structures. There are around 80 Morchella species. The best-known morel species are the edible or round morel ( Morchella esculenta ) and the bonnet morel ( Morchella semilibera ). ¹ The round morel ( Morchella rotunda ) and the common morel ( Morchella vulgaris ) are generally considered to be varieties within the same species ( Morchella esculenta ). Species differentiation is rather difficult and remains the subject of scientific debate. ¹²

Another use of morels is solid-state fermentation (SSF). Morels are used to break down starch and help to increase the nutritional value of corn flour during this solid-state fermentation. Oriental foods in particular are enriched with enzymes in this industrial method. ¹³

Literature / Sources:

1. Laessoe T. Mushrooms. The big identification book. Dorling Kindersley Publishers: London; 2014.
2. Mabey R. Edible. Wild plants, mushrooms, mussels for natural cooking. Haupt Verlag: Bern; 2013.
3. Müller R. Dried morels put to the test. Some mushrooms cause stomach ache. 09.05.2017 srf.ch [Internet]
4. Hall IR, Buchanan PK, Stephenson SL, Yun W, Cole ALJ. Edible and Poisonous Mushrooms of the World. Timber Press: Portland; 2003.
5. Groves JW. Poisoning by morels When taken with alcohol. Mycology. 1964;56(5):779–780. doi:10.2307/3756634.
6. Shavit E, Shavit E. Lead and arsenic in Morchella esculenta fruitbodies collected in lead arsenate contaminated apple orchards in the northeastern United States: A preliminary study. Fungi Magazine . 2010;3(2):11–18.
7. Dahlstrom JL, Smith JE, Weber NS. Mycorrhiza-like interaction of Morchella with species of the Pinaceae in pure culture synthesis. Mycorrhizae. 2000;9(5): 279–285. doi:10.1007/PL00009992.
8. Gang J, Fang Y, Wang Z, Liu Y. Fermentation optimization and antioxidant activities of mycelia polysaccharides from Morchella esculenta using soybean residues. African Journal of Biotechnology. Mar.2013;12(11):1239–1249, doi:10.5897/AJB12.1883.
9. Duncan CJG. Pugh N, Pasco DS, Ross SA. Isolation of a galactomannan that enhances macrophage activation from the edible fungus Morchella esculenta . Journal of Agricultural and Food Chemistry. 2002;50(20):5683–85. doi:10.1021/jf020267c
10. Elmastas M, Turkekul I, Ozturk L, Gulcin I, Isildak O, Aboul-Enein HY. Antioxidant activity of two wild edible mushrooms ( Morchella vulgaris and Morchella esculanta ) from North Turkey. Combinatorial Chemistry & High Throughput Screening. 2006;9(6):443–48. doi:10.2174/138620706777698544.
11. Ying J, Mao X, Ma Q, Zong Y, Wen H. Icones of medicinal fungi from China. Y.Xu. Science Press: Beijing;1987.
12. Kellner H., Renker C., Buscot F. Species diversity within the Morchella esculenta group (Ascomycota: Morchellaceae) in Germany and France. Organisms Diversity & Evolution. June 2005; Vol. 5/2: 101-107. doi: 10.1016/j.ode.2004.07.001.
13. Zhang GP, Zhang F, Ru WM, Han JR. Solid-state fermentation of cornmeal with the ascomycete Morchella esculenta for degrading starch and upgrading nutritional value. Journal of Microbiology and Biotechnology. 2009;26(1):15–20. doi:10.1007/s11274-009-0135-y.