The fruits in supermarkets are generally good-looking! Is it because they have been added with something "active"?

When you visit the fruit section of a supermarket, you will easily find a wide variety of strawberries, apples, oranges, cherries, tangerines, mandarin oranges, etc. Each one is plump and attractive, with bright colors, and they taste delicious just by looking at them.

However, many online self-media outlets claim that the reason these fruits are so beautiful is that they have been processed in a shameful way. This seems to be saying that "only fruits that don't look good are pure and natural and healthy to eat." But is this really the case?

Image source: Author

Let me start with the conclusion: Of course not!

The reason why fruits are becoming "more and more beautiful" is mainly due to the rapid development of planting technology in recent years. The development of technology not only makes the fruits taste better, but also makes their appearance more and more beautiful, all of which is to meet the needs of consumers for "both delicious and beautiful".

So, how does planting technology make fruits "both delicious and beautiful"?

Bee pollination

Makes the fruit healthy and plump

When we talk about bees, we immediately think of nectar collection and pollination. Indeed, many crops rely on insect pollination, and bees are undoubtedly the most critical pollinating insects. In the process of collecting nectar, bees transfer pollen from one flower to another, promoting cross-pollination of plants.

However, what you may not know is that the process of bee pollination not only significantly improves the success rate of plant reproduction, but also enables it to produce more healthy and plump seeds and fruits. For example, if there is a lack of bee pollination, the fruit yield of fruit trees such as apples, peaches, and apricots will drop sharply.

Chinese honey bee, source: photographed by the author

After bee pollination, the fertilization process of plants becomes more efficient, which in turn promotes the development of fruits and seeds. During the seed development process, the gibberellins produced will promote the expansion of fruits. This process not only optimizes the nutrient distribution of plants, but also improves their reproductive capacity, thereby significantly improving the quality of agricultural products.

For example, fruits pollinated by bees are superior to unpollinated or artificially pollinated fruits in terms of size, shape, taste and nutritional content . Take strawberries as an example. Bee pollination can make strawberries fuller, reduce the rate of deformed fruits, and increase yields by 30% - 50%. Fruits such as cherries and blueberries have higher sugar content and better taste after bee pollination. Therefore, bees not only increase yields, but also play a key role in the appearance quality of fruits and can improve the flavor of fruits.

The picture above shows the deformed strawberries that have not been pollinated by bees due to uneven pollination (the red fruit particles are pollinated achenes, and the white-green fruit particles are unpollinated achenes). The picture below shows the strawberries that have been naturally pollinated by bees (no deformity). Source: Photographed by the author

Winter pruning of fruit trees + thinning of small fruits

Can effectively avoid fruit nutritional deficiencies

Every autumn and winter, the temperature drops quietly, and nature has a wonderful "energy transfer" - the nutrients of fruit trees slowly flow back from leaves and branches to the trunk and roots. At this time, fruit farmers begin careful pruning to prepare for the next growing season of fruit trees.

Winter pruning is like a "cosmetic surgery" tailored for fruit trees. Fruit farmers cut off unnecessary branches, diseased and insect-infested branches, weak branches, and cross branches according to the expected yield target. This process is not only to remove those unnecessary "burdens", but also to allow nutrients to flow more concentratedly to those branches that are about to bear the heavy responsibility of flowering and fruiting. In this way, nutrients are no longer overly dispersed, thus preventing the fruit from becoming thin and of poor quality due to insufficient nutrition.

When spring comes and the pollination season arrives, whether it is careful pollination by humans or natural pollination by wind and insects, the fruit trees are gradually filled with small fruits. However, this is not the end, but the beginning of a new round of careful care.

At this time, fruit farmers need to thin out the fruits, which is a crucial step as it affects the size of the fruit and the final yield of the orchard. If the fruits are too dense, the nutrients will be overly dispersed, resulting in small fruits and sparse fruit clusters, poor appearance, and difficulty in selling at a good price.

Sunshine Rose fruit clusters before and after pruning (photographed by the author)

Take grapes as an example. Grape pruning not only focuses on the shape of the bunch and the shape of the grapes, but also the strength of the branches. Weak branches often cannot support the growth of the bunch, so the bunch cannot be left. For each bunch of strong branches, fruit farmers will carefully remove the side shoots and retain 15-16 small sub-bunches, so that the bunch becomes a single-layer, tightly arranged cylindrical fruit bunch or a teardrop-shaped fruit bunch. Such a fruit bunch has a beautiful appearance and can stand out in the market, becoming a highly favored premium product.

Proper fertilization can help

Fruits become larger and have better color

As the old saying goes, "Whether there is a harvest or not depends on water, and whether there is a harvest or not depends on fertilizer." Fertilizer is crucial to fruit yield and directly affects the appearance, taste and texture of the fruit. Proper fertilization can make fruit cells divide and expand better, and the fruit will naturally become larger . For example, the reasonable use of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer can increase the volume and weight of the fruit, and the fruit yield will also increase.

Fertilization also affects the color of the fruit . Nitrogen fertilizer can make the green color of the fruit brighter, while potassium fertilizer can make the color of the fruit brighter. For example, after potassium fertilizer is applied to grapes, the anthocyanin content increases and the color becomes darker red.

The flavor of the fruit is related to the content of soluble solids, which mainly include sugar, acid, vitamins, etc. Appropriate fertilization can increase the content of soluble solids. Using organic fertilizers can increase soil organic matter, allowing fruit trees to better absorb nutrients, and the soluble solids content of the fruit will be higher. Potassium fertilizers and calcium fertilizers can make the fruit cell walls thicker and more resilient, and the fruit will taste crisper and tender. However, if too much nitrogen fertilizer is used, the fruit cell walls will become soft, the taste will be poor, and it will not be resistant to storage and transportation.

Therefore, if the fruits are to be large, good-looking and delicious, the ratio and timing of fertilizer use are the key.

Fruit farmers will use methods such as "twisting branches to rotate fruits"

Promote the sun exposure on the fruit surface

When buying apples, oranges, watermelons, grapes and other fruits, you may occasionally buy fruits with one side brightly colored and the other side whitish or green. This is most likely due to the sun.

Here are some examples: the ultraviolet rays in the sun stimulate the synthesis and accumulation of anthocyanins in grapes, making the grapes turn purple and red; and the pigments such as anthocyanins and carotenoids in apples will also be affected by ultraviolet rays. Ultraviolet rays can promote the decomposition of chlorophyll in the apple peel into anthocyanins and carotenoids, thus showing a bright red color. The part of the fruit that is not exposed to the sun may turn white and green. So the question is, the sunlight is sprinkled from the sky, what about the bottom of the fruit?

In order to allow sunlight to reach the fruit, fruit farmers generally promote uniform coloring of the fruit surface by twisting branches, rotating fruits, picking leaves, and laying reflective film. For example, during the process of watermelon cultivation, the watermelons are "turned over" many times during the fruit expansion and ripening period, which can make the skin color even without yellow spots. In the process of apple cultivation, reflective film is used a lot. Reflective film is generally laid under the tree when the fruit is about to change color, combined with operations such as twisting branches and picking leaves, to increase the area of ​​the entire fruit that is illuminated, so that the overall color of the fruit is very consistent.

Laying reflective film in apple planting is conducive to uniform coloring of apples (taken from Douyin)

Bagging the Fruit

Make the peel thinner and color more evenly

There is a technology that uses physical means to put a protective cover on the fruit, which is fruit bagging. Fruit bagging can prevent pests and birds from reaching the fruit, and it can also isolate dust and stains, and avoid sunburn and various abrasions and bruises. After bagging, there is less harm from pests and diseases, and the number and amount of pesticides used will be greatly reduced, which not only saves the cost of pesticides but also reduces pollution to the environment.

In addition, bagging has some other advantages. For example, after bagging apples, the peel becomes thinner and more delicate, and the coloring is faster and more even after the bag is removed. Fruits such as apples, pears, and grapes are generally packed in paper bags with better air permeability, while tropical fruits such as bananas and mangoes are packed in cheaper plastic bags.

Grapes are grown to avoid rain and the fruits are bagged (photo taken by the author)

Before bagging, the fruit needs to be sprayed to prevent pests and diseases. This is usually done in the middle of the fruit growth period, and the specific time varies depending on the type of fruit. For example, apples and pears are usually bagged about 30 days after the flowers have faded.

Spraying lime water on the surface of the mandarin oranges during cultivation to protect them from the sun (taken from TikTok)

During the cultivation of Wogan, especially in the summer when the temperature is high and the sun is strong, the fruit is easily damaged by sunburn. Sunburn can cause sunburn on the surface of the fruit, forming scars, and thick and mottled skin, which affects the quality of the fruit. Fruit farmers will spray lime water on the surface of Wogan fruit, which will form a white protective layer on the surface of the fruit, reflecting sunlight and playing a sunscreen role, just like people applying sunscreen in summer to protect themselves from the sun.

After reading this, you may ask: Once the lime water is sprayed, the fruit will be covered with white lime, which doesn’t look good... Don’t worry, read on.

Give the fruit a “bath”

Put on "new clothes"

Some fruits picked from the orchard will be carefully washed. Washing can not only wash away the dust, stains, germs and pests on the surface of the fruit, but also reduce the temperature of the fruit, avoid rotting due to excessive respiration, and thus extend the storage time of the fruit. Usually, the objects of washing are mainly fruits with thick peels, such as citrus fruits. They will use physical methods such as brushes and rollers to clean the surface of the fruit (of course, there will be no traces of lime water).

After washing, some fruits are carefully waxed. After waxing, the appearance of the fruit becomes bright and smooth, and the glossiness is greatly improved, as if it is covered with a gorgeous coat. This layer of wax forms a protective film on the surface of the fruit, just like applying hand cream to the fruit in the dry winter, allowing the fruit to better retain moisture, while greatly enhancing the antibacterial ability and greatly extending the shelf life of the fruit. Therefore, this fruit wax that can both improve the appearance of the fruit and resist bacteria and preserve freshness is deeply loved by consumers.

It is worth noting that regular fruit wax is edible grade, and is a natural wax extracted from animals and plants (such as beeswax, carnauba, crab shells, etc.), which meets food safety standards and is harmless to the human body. However, in extreme cases, some unscrupulous merchants may use industrial wax instead of fruit wax, or spray fruits with excessive amounts of pesticides to preserve them. Therefore, when buying fruits, be sure to choose regular channels such as large supermarkets to ensure food safety and health.

The rapid development of agricultural technology has enriched our dining table. We can more easily enjoy fruits that are cheap, fresh, beautiful and delicious. However, consumers are easily misled and fall into a prejudice: if the fruit is too beautiful, it must be the product of "hard work". The actual situation is that consumers' demand for "beauty" has promoted the advancement of technology, and technology plus the hard work of fruit farmers have jointly created the beautiful fruit in front of you.

Planning and production

Author: Zhang Cong, a graduate student in agronomy and seed industry, majoring in vegetables

Review丨Yang Laisheng, Researcher at Lanzhou Academy of Agricultural Sciences

Planning丨Ding Zong

Editor: Ding Zong

Proofread by Xu Lai and Lin Lin