Are walnuts suitable for people who often use their brains to eat more of?
Mentionwalnuts, and you will most likely think of Tchaikovsky's famous ballet"The Nutcracker", though fewer people have read its original source, Hoffmann's "The Nutcracker and the Mouse King." What we usually come into contact with nowadays are adapted works, but the wildly imaginative ideas and the beautiful elements they convey, such as unity and warmth, have largely been preserved.
Walnut fruit. Image: George Chernilevsky / wikimedia
December 18, 1892, St. Petersburg, the premiere of "The Nutcracker." Image: wikimedia
Why need a phone to crack a walnut
Walnut, which is what we usually callwalnut, and a "nutcracker" is something likewalnut pliers.
Like toys and like ornaments, all kinds of nutcrackers are themselves quite exquisite. Image: pixabay
When I was little, I always thought the"toy soldiers"in "The Nutcracker" were made from walnut shells, which is why it was called a nutcracker, and I also firmly believed it should be a walnut "box," and only later did I learn that it is actually a walnut cracker shaped like a toy soldier, which shocked me for a long time.
It probably cracks the walnut open by "biting" it like this. Image: pearlvids / youtube
Truly related to walnuts,fairy talesthere are quite a few more; in Grimm's Fairy Tales there are several passages about opening walnuts and obtaining various items, for example in "The Iron Stove," the three walnuts the princess opens all contain magnificent dresses. Well, it was precisely these stories that deepened my mistaken fixation back then on the "walnut box."
The "foreign" peach
According to legend, walnuts during the Han Dynastywere introduced to China from the Western Regions, so at the time they were called the "foreign" peach. During the Eastern Han period, "walnut" began to have clear written records, such as in the late Eastern Han "Kong Rong's Letter to Various Gentlemen," which says, "The other day you kindly gave many walnuts, and I deeply understand your sincere regard."
At the time, the walnuts that flowed into China from the Western Regions were basically only the fruit, mostly brought in by merchants traveling between the Western Regions and the Central Plains or tribute offered by envoys. In the translation of Indian Buddhist scriptures of the same period, Buddhist principles explained through Indian walnuts appeared, so some people believe that another portion of walnuts was introduced from India by monks.
Walnut is monoecious with unisexual flowers. Image: JOfoto & Georg Slickers / wikimedia
Although walnut fruit entered China at that time, the walnut tree and its cultivation methods had not yet been introduced or spread. Limited bytransportation and storage conditions, walnut fruit spoiled easily, and after about three years of storage the fruitcould hardly sprout and emerge as seedlings, so at the time walnuts successfully grown from fruit were rarely seen.
It was not until the Two Jins periodthat in the Tibet areapeople gradually began to transplant walnut trees from India, extending all the way toward the Central Plains, and afterward tried planting from the walnuts the trees bore. From then on, the walnut tree truly entered the Central Plains and spread widely.
A walnut tree in autumn. Image: JLPC / wikimedia
Walnuts are not true nuts?
Today, walnut is already a very common "dried fruit," but it is not a true nut.Botanically, a "nut" refers to a fruit composed of a hard pericarp and a seed, and the pericarp does not split open when the fruit matures, such as hazelnuts and chestnuts. In everyday life, "nut" refers to a broader range, and things like pistachios, which have a hard shell and can be eaten, are all called "nuts."
After the walnut matures, the pericarp splits open, and inside is the familiar "walnut." Image: B?hringer Friedrich / wikimedia
Anyone who has peeled a "green walnut" surely knows that the hard walnut we usually eat is actually only its pit, and outside there is still a layer of inedible green pericarp, so the walnut is adrupe。
similar to peach and plum. In the figure, the white text is the botanical drupe, and the green text is the nut. Image: David Burton / FLPA / mindenpictures
In addition, anyone who has peeled a green walnut will surely be deeply impressed by its pericarp - it looks like an ordinary green outer skin, and during peeling there seems to be nothing special, but after a little while you will find,why has the place touched by green walnut juice all turned black?!
This is because green walnut peel containstannins, and after contacting the skin, throughoxidationit takes on a brown color, and its adsorbency is extremely strong; once it gets on the hands, it simply cannot be washed off with water no matter what, and most of the time one can only wait for the skin to metabolize and fade. Some people's skin, after touching the juice of walnut peel, not only turns black but alsobecomes red and itchy; this is because walnut peel also contains some irritatingquinones, which can trigger contact dermatitis and produce allergic symptoms.
Perhaps the most troublesome snack to eat
However, even if the blackening, itching green outer skin is removed in advance, the hard walnut is still difficult to deal with -How happy a thing it is when someone cracks the shells for you while eating walnuts。
Botanically speaking, the part we eat is actually the cotyledon of the walnut. Image: fir0002 / wikimedia
Among the popular dried fruits there is one that looks similar to walnut, namely"pecan", and it truly is a distant relative of the walnut - the fruit of the American hickory Carya illinoinensis from the Americas. Pecans have along and narrowshape, and are naturallythin-shelled, making them easy to flavor and easy to crack open and eat, and more suitable as a snack than walnuts.
Pecans. Image: pixabay
Among domestic plants there are also several similar to walnut, such as the“"small walnut"that can be seen in the north (Manchurian walnut Juglans mandshurica), as well as theChinese hickoryCarya cathayensis that can be seen in the Anhui and Zhejiang areas, whose taste is about the same as walnut, only the kernel is relatively much smaller.
The Chinese hickory kernels of Lin'an, Zhejiang, are relatively famous. Image: King of Hearts / wikimedia
To be honest, walnuts are really not a conventional choice for a snack. First, cracking them in the shell is troublesome; second, even if you directly buy walnut kernels to eat, the taste is somewhat astringent and unpleasant.
Besides the green pericarp, the seed coat of the walnut kernel also contains tannins, so walnut kernels taste astringent. But now there are many ways to solve this problem, and my favorite method is to make"amber walnuts"using a sugar coating to mask the bitterness - a sweet, fragrant, crisp calorie "bomb" is of course a good snack (serious face).
Once this mouth starts, it cannot stop. Image: Chao Shi Kong / Douguo Meishi
Can eating walnuts really "nourish the brain"?
Many people eat walnuts not to enjoy the pleasure brought by high calories, but because they believe walnuts can "nourish the brain." Some people simply believe in "nourishing the form with the form," while some people who do not believe in "nourishing the form with the form," after studying the components of walnut kernels, also begin to accept the view that they are beneficial for "nourishing the brain."
The Omega-3 fatty acids and zinc contained in walnuts do indeed help brain function, but eating walnutsonly supplements the nutrients the human body needs, merely making the brain temporarily "more energetic." In fact, when a person is born, they almost have all the brain neurons they will have in their lifetime, and the brain no longer grows after completing brain fissure formation. After a certain stage, brain neurons gradually decrease with age - if one wants walnuts to take on the task of replenishing them back, it is really a bitof forcing a "walnut" to do what it cannot.
Then does that mean a walnut that has been caught in a door can... (No! Image: Fir0002 / wikimedia
That said, although walnuts cannot make brain neurons continue to grow and complete "brain nourishment," they still have a certain effect in supplying energy for brain activity and providing needed elements, and cracking two walnuts a day is indeed beneficial for people who use their brains heavily.
Besides eating, they can also be "played with"
Besides the edible ones, there is another type of very famous walnut, namely"wenwan walnuts"。
At first, wenwan walnuts did not include the pits of the main subject today, the walnut, but rather the pits of the just-mentioned Manchurian walnut or Ma walnut (a variety of Manchurian walnut); the surface of these pits iseven more "pitted and bumpy" than walnut, and the shell is thicker. People select "Ma walnuts" with beautiful grain patterns and regular shapes, and after carving and years of handling and playing, they appear to have a "unique" charm.
Panjiayuan in Beijing, home to the largest second-hand goods market in all of China. Image: Yunji / Oriental IC
At first, wenwan walnuts were mainly playthings of "nobles," and with the changes of the times, there is now a fairly considerable group of enthusiasts, and many people are willing to spend large sums to buy wenwan walnuts in good condition.
Where there is a market, there will naturally be people with crooked ideas, and standards for various new-style wenwan walnuts began to appear, and gradually there were also "wenwan walnuts" made from walnut pits. However, matters in this area are rather subjective, and whether they are really just inferior goods passing themselves off as good is hard to say; in short, friends who are new to the hobby should study carefully themselves.
This article is the 284th article of the 4th year of Species Calendar, from Species Calendar author @ArcherEmiya.