Shiitake

Description

The Shiitake mushroom is one of the best culinary mushrooms. Especially in Japan and China it is used a lot in the kitchen. Not only because of its taste, but also because of its medicinal properties. 

The Shiitake has its origins in Asia, especially China, Japan, Korea, Vietnam and Thailand, and has been cultivated here for centuries. Originally it grows mainly on hard wood, including oak, walnut, sweet chestnut and beech. In fact, it parasitizes this tree species and feeds itself on the dying wood. The mushroom has a light to dark brown cap. The gills under the cap are attached to the stem and run off. In young mushrooms, the cap is slightly rounded inward. There are two types of Shiitake mushrooms on the market. The most common one is the species with thick, fleshy hats. This is also called Tong gu in Chinese. The other, less used species has a wider opened cap and thinner flesh. This species is called Koshu. The Shiitake belongs to the most cultivated mushrooms in the world. Approximately 83% of the entire Shiitake production takes place in Japan. Also in the Netherlands and Belgium the variety is very popular and in the nowadays there are some nurseries here as well. Originally, the Shiitake mushroom is cultivated on wood stems. In the meantime this also happens in other ways, mainly on wheat straw, oak sawdust and water.

As a medicinal mushroom Shiitake has a beneficial effect on cholesterol levels and blood pressure. The mushroom, or a supplement, should be taken regularly. Too high a blood pressure can lead to problems with the heart, including a heart attack or stroke. A study done with rats shows how Shiitake mushroom helps to lower blood pressure. For nine weeks the rats were given 5% Shiitake in powder form together with water. After this period their blood pressure and cholesterol levels were lower. 

In Traditional Chinese Medicine Shiitake is used for numerous applications. Already in times of the Song Dynasty (960- 1127) the Shiitake was cultivated for medicinal use. Shiitake is mainly prescribed for problems with the heart, but also for cancer. Furthermore, the mushroom is advised for people with a weakened immune system. Also in Japan, Korea and in the east of Russia the Shiitake has an important role as a medicinal mushroom. Here it is used to keep the body young and vital and to keep the blood circulation flowing well. In the traditional medicine of Japan it is used in cases of exhaustion and problems with the liver. The polysaccharides present in Shiitake could possibly play an important role in helping the immune system ward off diseases and infections. The anti-inflammatory effect of Shiitake also helps to slow down the ageing process. Chronic inflammations can cause pain in the joints, weight gain, anxiety, sleep problems and problems with the intestines. An unhealthy lifestyle with little exercise and a 'typical western diet' can lead to chronic inflammation. 

People who have too much fat in their daily diet have a higher risk of high cholesterol levels. The risk of liver damage also increases. A study with rats looked at how Shiitake could counteract the harmful side effects of a diet that is too high in fat. The rats were given a Shiitake supplement for one month (100mg/kg per day). As a result, the supplement counteracted the oxidation of fatty acids and reduced the harmful parameters of an overfat diet.

Botanical name

Lentinula edodes

Common names

The name Shiitake comes from Japanese. It’s is a combination of 'mushroom' (take) and 'that grows on the pasana tree' (shii). In China this mushroom is also referred to as Xiang gu, which means 'good smelling mushroom'. 

Active ingredients

Shiitake contains several active substances, including vitamins, minerals, amino acids, alkaloids (eritadenine) and organic acids. It also contains the active polysaccharides (beta-1,3 D-glucans, lentinan).

Shiitake contains a large amount of vitamin C and B vitamins (including vitamin B-5 and B-6). It also contains copper, magnesium, vitamin D and fibers. Four Shiitake mushrooms provide 39% of your daily requirement of copper, 33% of your recommended daily allowance of vitamin B5 and 10% of your recommended daily allowance of selenium. Vitamin B-5 is, among other things, important in maintaining healthy skin, hair and nails. Shiitake also contains niacin (Vitamin B-3). This vitamin is important in maintaining your energy level. Shiitake mushroom also contains significant amounts of zinc. Zinc helps the body fight oxidative stress and prevent infections. Stopping oxidative stress slows down the ageing process.

It contains very few calories (only 44 calories per 15 grams of dried mushroom). As a vegetarian it is interesting to consume Shiitake regularly. It contains many of the same amino acids that are also present in meat. The ingredients responsible for the cholesterol-lowering effect are the polysaccharides, terpenoids and lipids. Shiitake also contains a substance called lentinan. This polysaccharide can slow down the growth of leukaemia and is therefore promising in the treatment of cancer. In Japan and China, lentinan is prescribed by doctors as an additional therapy in the treatment of stomach cancer. One of the reasons for this is to boost the immune system. 

Use

In Asia you can find the Shiitake mushroom in many dishes, including Shiitake soup and wok dishes. The taste of the mushroom is full and spicy. When dried, it enriches its taste even more. In its dry form, it has more of an umami flavour, which is much appreciated. Umami is described as the 'fifth taste', in addition to sweet, sour, bitter and salty. This taste is fleshy and savoury. 

As a supplement you will find Shiitake in the form of capsules, which can easily be taken. In this way you can easily and relatively cheaply take in your daily quantity of Shiitake. It is important to choose an organic Shiitake supplement. The mushroom easily absorbs substances from its environment, both favourable and unfavourable. Organic production only guarantees the desired contents, without harmful toxins such as pesticides, herbicides and chemical fertilizers. 

Warning

Generally Shiitake mushrooms are very safe. Some people may show an allergic skin reaction after consuming a product containing Shiitake. This can lead to red spots on the skin, which disappear after 3 to 21 days. Usually this concerns the raw or not properly cooked mushroom. In very rare cases it also occurs in preparations of the mushroom. 

Cultivation

Originally the Shiitake grows on dying wood from hardwood tree species. Meanwhile, they are also grown on a substrate that is colonized with mycelium. The substrate is often a mixture of sawdust, straw and water. 

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