Walnut trees are large trees found on all continents and of which there are about twenty species.
There was a walnut tree in Europe but it did not survive the last glacial episodes of the Quaternary.
The common walnut, Juglans regia, is native to the mountainous regions of Asia located between western China, northern India and Iran.
It is such an interesting tree that it was disseminated very early in antiquity further west, first in the region of Iran and present-day Turkey then throughout the Mediterranean region, and finally in the Western Europe.
Sailors then introduced it to the Americas, Australia and New Zealand.
It is a slow growing tree which does not generally bear fruit for 7 years, sometimes longer, but whose longevity is important (100 to 200 years, even more).
The walnut leaves, large enough and long stalked, are composed and imparipinnate, they give off a very characteristic odor when crumpled.
The female flowers are very discreet, greenish, at the end of the small branches, the male inflorescence consists of hanging catkins.
The Fruit is a drupe (the nut) with a green and fleshy pericarp (husk) which covers a shell with two valves which contains the oilseed with the appearance of a small brain (cerebroid).
CHEMICAL COMPOSITION AND PROPERTIES
Green leaves and walnut husk stain contain oxygenated aromatic compounds (naphthoquinones), the most specific of which is juglone, flavonols (hyperoside, junglanoside), and gallic and ellagic tannins.
These substances are also present in tree bark and roots as well as in male flowers (catkins).
Tannins are astringent (forming a chemical complex with proteins and drying up mucous discharge), antiseptic and healing, anti-inflammatory and anti-free radical.
Juglone is a yellow coloring substance for the skin and integuments, anti-inflammatory and apparently active against many microorganisms (bacteria, pathogenic fungi, viruses) and parasites.
It is also cytotoxic and capable of destroying the cells of the epidermis (in particular the keratinocytes which ensure the good health of the skin).
Naphthoquinones (including juglone) contained in walnut leaves that have fallen to the ground and possibly exuded by the roots act as herbicides on plants around walnut trees, considerably limiting their development.
These substances are also toxic to herbivores, especially horses.
Walnut stain is particularly rich in tannin and naphthoquinones (coloring substances).
Some people are allergic to extracts from walnut leaves and walnut husk.
THE WALNUT OF THE COMMON WALNUT JUGLANS REGIA
The shell has no medicinal use.
The almond or kernels (the two cotyledons in the shape of a small brain) are covered with a thin film which contains tannins.
The chemical composition of the walnut varies a little depending on the varieties of walnut (there are many cultivars) and the growing conditions (terrain, climate).
Average composition of a dry nut:
carbohydrates: 13%, half of which is insoluble fiber
lipids: 65% to 70%
water: 4% to 7%
The almond of the walnut has an interesting content in vitamin B1 and B6, and in minerals (iron, manganese, zinc, calcium and potassium)
The quantity of lipids (fatty substances) is of great interest, especially since the percentage of unsaturated fatty acids is high, and well balanced in its omega 3 / omega 6 ratio.
Walnut is very high in calories: around 650 Calories per 100 g of dry walnut without their shell.
People allergic to nuts (peanuts, hazelnuts, macadamia, para nuts, etc.) should test their sensitivity to nuts before consuming them.
Analysis of the fatty acids of the walnut of the common walnut:
palmitic acid (saturated) 5 to 7%
stearic acid (saturated) 2 to 4%
oleic acid (monounsaturated) 20 to 40%
linoleic acid (bi-unsaturated omega 6) 40 to 60%
alpha linolenic acid (tri-unsaturated omega 3) 7 to 12%
Walnut oil is therefore a fluid oil but which tends to oxidize quickly especially if it is heated (it becomes rancid and polymerizes, it is drying) because it contains a high percentage of unsaturated fatty acids.
It contains fatty acids which the body needs but cannot synthesize (essential fatty acids) in a balanced percentage.
It is therefore a very good dietary oil for seasonings but not for frying.
Numerous recent studies have shown that regular consumption of a small amount of walnut or walnut almond oil improves the bad cholesterol / good cholesterol ratio in people with excess and imbalance of cholesterol, an abnormality of their LDL / HDL ratio, as well as in people who have too much triglyceride in their blood (dyslipidemia).
GREEN WALNUT AND WALNUT LEAVES
They are used for their tannin and juglone content. In any case the treatment should not exceed 15 days because of the possible side effects of juglone.
- To dry out inflammations of infectious origin of the digestive mucous membranes (of the oral sphere) and genital: gingivitis, glossitis, mouth ulcers, leucorrhoea, vaginitis.
- In certain skin disorders: eczema, acne and chronic skin infections, sweating disorder, hyperhydrosis.
- To try to balance type 2 diabetes and prevent complications.
- In certain digestive disorders which are part of irritable bowel syndrome or which follow an imbalance of the intestinal flora and which are often associated with acne or recurrent skin infections: false constipation which is accompanied by secretion with abundant mucosa and intestinal cramps, watery diarrhea without the smell of fermentation.
A handful of fresh green leaves or 10 g of dry leaves in 1 liter of water for the oral route and 1/2 liter of water for external treatment, boil 2 to 3 minutes, infusion 10 to 15 minutes.
One cup once or twice a day by mouth (diabetes).
Mouthwash twice a day (inflammation and infection of the mouth).
Skin application on a gauze that is kept for one to two hours or in a foot bath diluted in lukewarm water.
Vaginal irrigation once or twice a day (leucorrhoea)
Alcoholic tincture of walnut leaf or husk
and glycerine maceration of buds
These are preparations that are easier to store, dose and use.
10 to 50 drops of tincture 3 times a day for a maximum of two weeks then 15 days of therapeutic discontinuation.
30 to 50 drops of 1D glycerine maceration for a maximum of two weeks then 15 days of therapeutic discontinuation.
The alcoholic tincture can be diluted 1/5 or 1/10 with boiled water and used in the same way as the aqueous decoction.
Walnuts are an interesting food, but they can only be eaten in small quantities because they are very rich in fat and also contain tannins.
Several studies show that the regular daily consumption of the equivalent of 20 to 25 g of shelled walnuts (or 2 to 4 nuts depending on their size) improves the composition of blood lipids (cholesterol, triglycerides and HDL and LDL lipoproteins).
It is of course necessary to take into account the calorie intake (120 to 150 Kcal).
Regular consumption of fresh and dry nuts helps ensure a good balance of the intestinal flora with sometimes an improvement in irritable bowel symptoms and regularization of intestinal transit.
WALNUT CULTIVATION, NUTS HARVESTING, WALNUT OIL
One can put in the ground (in place or in seedlings) the fresh nuts in the fall and they germinate in the spring, after 2 to 3 years the small walnut tree is in put in place.
When you want a particular variety, grafting is imperative.
It must be remembered that the walnut is a large tree which can hamper the development of other plants or trees.
Walnut trees are now very often grafted onto a rootstock (black walnut for example) that grows faster and is resistant to certain diseases of common walnut.
Fresh walnuts can be chopped before full maturity when they are still in their green envelope, they are then eaten by removing the thin film covering the almond. The mature nut is dried for one to two months and more if one wants to obtain quality oil, it can be kept dry until the next harvest.
You can extract walnut oil in a traditional way, but you need a small but powerful press.
The almonds (kernels) of the very dry walnuts are finely crushed in a chopper (like a meat grinder) then slightly heated without exceeding 50 °.
They can then be pressed by putting the hot dough in a very solid cloth, the walnut oil weakly colored in yellow keeps quite well in glass containers (if possible tinted) in the dark and in a cool place.
Some people may be allergic to walnut leaves and therefore to their extracts (infusion, alcoholic tincture, shampoo). Food allergy to nuts is possible and more dangerous because the allergic shock is more violent, this allergy is most often crossed with allergy to other nuts (almonds, hazelnuts, macadamia nuts, Para nuts) and peanuts .
WALNUT WINE AND WALNUT HUSK LIQUEUR
These preparations are more anecdotal but traditional, they can nevertheless be considered as medicinal preparations.
WALNUT WINE: macerate 200g of chopped fresh leaves in a liter of good white wine for 4 or 5 days, sweeten as desired and filter.
WALNUT HUSK LIQUEUR: macerate for 3 months 500g of green walnut bark or walnut husk cut into pieces in a liter of ethyl alcohol at 45 ° (rum for example); filter and mix with 3 liters of wine, sweetening as desired, then consume before the meal, once or twice a day.
These two preparations retain the tannins and the juglone but remember : alcohol and sugar mixture is not a recommended diet.
A BEAUTIFUL TREE WITH EDIBLE ALMONDS AND MEDICINAL LEAVES
The common walnut, Juglans regia native to Asia provides a quality wood and an annual harvest of edible nuts which contain a dietary oil.
Its leaves and parts of the fruit contain medicinal tannins and antibacterial and antifungal quinones..
Copyright 2020 : Dr Jean-Michel Hurtel