what? "Shanzhai" is so fierce that you can't even eat authentic fruit these days? Calm down! In fact, "pulp" is a non-existent concept in botany. So, after eating fruit for so many years, what are we eating? It depends on whether you eat apples, peaches, grapes, oranges or watermelon... Please read on!
Peach: classic "pulp"
First, let's understand the development process of a typical fruit.
When the fruits are still flowers, the seeds are not seeds, but called ovules. These little guys who repose the future of the plant are born in the ovary, the belly of the pistil of the flower, which is protected by the wall of the ovary. With the success of fertilization, the calyx, corolla and even stamens used by flowers to help fertilize pistils degenerate and disappear one after another, while the ovule - the future of these plants began to grow healthily, and the ovary protecting them also developed, replacing the calyx and corolla as the most dazzling part of the plant: Fruit. Accordingly, the inner and outer epidermis of the ovary wall and the basic tissue in the middle develop into the inner, outer and mesocarp of the fruit respectively.
Peach is such a typical fruit. Its endocarp (the inner epidermis of the ovary wall) is petrified into a hard shell and coated with only one seed to form a peach kernel. The pericarp of the pericarp is much thinner than that of the pericarp. The basic tissue in the center of the typical fruit ovary wall naturally and smoothly received the important task of attracting predators, and the meat turned into plump and juicy peach meat.
In this way, the three parts of the ovary can develop into typical fruits with skin, pulp and hard core respectively, as well as sister apricots, plums, plums and cherries with the same door as peaches, as well as jujubes far away from each other. They have a common name in Botany - "stone fruit".
Grape: expansion of "pulp"
There is still a lot of pressure for the ovary to produce "pulp", not to mention whether the ovary can successfully develop into fruit by itself. It is not easy to let the layers of the ovary wall develop into inner, middle and outer pericarps independently, just like grapes.
Grape belongs to the "berry" in botany. This kind of fruit may be too much in pursuit of the "juicy" ultimate state of pulp, and even turn the endocarp into the same meat quality as the mesocarp. More extreme is that some endocarps even give up the existence as a whole of the "skin" and liquefy the juice, thus completely leaving the task of "the last line of defense of the seed" to the seed itself. If you don't keep the outer peel to keep the water and structure intact, I'm afraid all the peel of the berry will become sugar water to please the eater.
However, it is precisely with the spirit of pursuing the ultimate pulp of berries that we can have sweet and juicy fruits of different schools, such as grapes, kiwi fruit, tomatoes, blueberries, blackcurrants, persimmons and guava, to satisfy our appetite.
Orange: eat wool?!
The pulp of the berry can be said to be the expansion of the mesocarp and the annexation of the endocarp, while the edible part of another kind of fruit in Botany - "citrus fruit" - completely retreated to the endocarp and abandoned the base of the mesocarp. This is the fruit of Citrus in Rutaceae, such as orange, grapefruit, orange and lemon.
The so-called "orange peel" actually contains the outer and middle layers of peel. The exocarp developed from the outer wall of ovary still plays the role of exocarp, but many oil cells are involved. The mesocarp has changed a lot. Once it was the existence of pulp, it has reduced to a part of the outer skin in the citrus fruit. It gradually looses inward and becomes an "orange collateral", which has become a few tasteless and stripped away part.
Thus, the burden of forming pulp is transferred to the endocarp. At the same time, because there are more seeds, the endocarp is dispersed into many small compartments, namely ovary, each containing several seeds. The glandular hairs growing inward from the endocarp turn into fleshy juice sacs - which become the orange petals we throw into our mouths.
Pear: suck ovary
Even if the layers between the skins are unknown like berries, the above three fruits are completed by the ovary independently. However, it is not a small house that can be reliable. When the children themselves suck up, the fruit will have to be helped by other parts.
When you pick up a Yali pear, in fact, you can't see the part developed by the ovary itself. That's because the ovary of Yali pear has been hiding in the embrace of the receptacle since the flowering period. With the development of the fruit, the receptacle and ovary are healed together. Even the skin and pulp are both fleshy, which can't distinguish you from me. Therefore, the receptacle, which supports the tasks of various parts of the flower during the flowering period, not only cannot complete the task and retire with honor in the fruit period, but also needs to develop again and work for the seeds with the ovary - what an uneasy ovary
Not only the ovary of Yali pear is so unreliable. Its brothers such as apple, hawthorn and loquat also need the power of receptacle to produce their own fruits. However, with the help of the receptacle, the endocarp of these fruits can be vacated to form a relatively hard seed protective layer. They are "pear fruits" in botany.
Watermelon: supporting actor's victory
Similar to Yali pear, the "Hu (H ù) fruit" of melons such as watermelon is also a "lower ovary", that is, the ovary has been hiding in the embrace of the receptacle since the flower period until they heal. However, the flower receptacle of all kinds of melons may be more open-minded, not mixed with the formation of pulp, but developed into the hard skin of fruit together with the outer peel, returning the task of attracting predators to the two layers of peel inside. Therefore, some people call bottle gourd "berry type" fruit. The edible parts of white gourd and Hami melon are the same as berries, which are the middle and inner peel of the expanded pulp.
But the story doesn't end here. During the flowering period of melons, there is also a protuberance on the inner wall of the ovary for the ovules to grow on and absorb nutrition. This is placentation - in fact, all fruits have placentation, but most of them are very low-key in other fruits. Only in the bottle gourd, the humble supporting role of placentation gets the opportunity to show itself - watermelon is the ultimate development of placentation.
Speaking of this, have you found that there are actually two things with different purposes that taste very similar? By the way, the inner side of the so-called "watermelon peel" is actually the same as the Hami melon flesh, which is the flesh formed by the inner and middle peel. The soul of watermelon - the crispy and sweet melon pulp is actually the placenta in the fruit period - that is, the sweetest part of Hami melon that is often thrown away because it is wrapped with seeds.
Strawberry: no or too much
When it comes to the fleshy receptacle, we have to mention the strawberry, because the fleshy part of the whole strawberry is formed by the expansion of the receptacle, but the pear fruit is the receptacle outside the fruit, and the strawberry is inside the fruit. So where did the ovary of strawberry change in fruit period?
From watermelon to grape, the fruit is developed from the only ovary in the flower, which can be collectively referred to as "single fruit", while the flowers of other plants have many independent ovaries, so when each ovary develops, there are many small fruits. However, the space in a flower is very limited, and the small fruits grow into a whole, that is, the "aggregate fruit" in botany. Strawberry is a kind of aggregate fruit.
In this way, strawberries should not have no ovary, but should have many. Yes, the "seeds" on the surface of strawberries are actually small fruits - "achenes" developed by non fleshy ovaries. What is achene? All you need to know is that they don't have any meat all over them, which is different from raspberries that are polymerized fruits - the small fruit of raspberries is stone fruit, so they eat the flesh developed from mesocarp.
Pineapple: great collective strength
In addition to aggregate fruit, another compound fruit is the botanical "aggregate fruit". This group of guys is powerful. Whether single fruit or aggregate fruit, each flower develops into a fruit, while "fig" is a fruit squeezed out by several flowers (an inflorescence).
Because it involves the whole inflorescence, the flower axis connecting each flower in the inflorescence inevitably participates in the composition of fruit, the most obvious is pineapple.
Pineapple is actually developed from a string of florets. Its edible part involves the flower axis, bracts and ovary of florets in the inflorescence, which are all fleshy and healed together, while the petals and calyx of each floret are hardened and chimeric with each other to form the outer skin of pineapple.
Another group of figs with figs is figs, figs, jackfruit, mulberry and other mulberry plants. However, the flower axis of mulberry is not developed. Its edible part is composed of fleshy calyx of florets. The edible part of fig is very similar to pineapple, but the bowl structure that wraps all the florets is really difficult to bear the name of flower "axis".
Litchi: a sudden rise
Skin, flesh, hard core, isn't this a standard stone fruit? Why should litchi be listed separately? In fact, the edible part of litchi is not only not a typical pulp, but also has begun to break away from the category of "fruit" from a certain point of view.
"Eat 300 lychees a day" -- if Mr. Su Shi ate the peel, I'm afraid the second half of the sentence would become "long words don't be Lingnan people", because all the peel of lychee together form the peeled part, which is really bitter and difficult to handle. Is Su Shi eating a placenta on the inner wall of the ovary? The reason why the placenta is a placenta is that there are seeds on it, but there is a vacancy in the litchi meat where the seeds are connected with the fruit - obviously, it is not the placenta that becomes crystal clear. At this point, all parts of the ovary have been excluded. What is inside? Yes, it's an ovule.
The development of ovules is one of the most complicated processes of plants. Litchi ovules are more special. When they develop, there will be some appendages along with them, and the meat will expand - as you expected, this is the transparent and delicious "flesh" of litchi and the "false seed coat" of litchi. There is no dispute about the definition of lychee and longan, which are not common.
After reading so much, do you know which part of fruit you usually eat? In the future, can we talk like this: "Hey, tonight's dessert is a mixed salad of a false seed coat, a mesocarp and a placenta!" "If you continue to sit in front of the computer, the aril will be robbed!"