Credit for the sun

In our life, with the progress of the times, the gap between the interests of young people and the older generation is getting bigger and bigger, but there is one activity that is considered a tacit agreement among all ages until now, and that is to put the quilts in the sunlight when the sun is shining.

When I was a kid, I could see the quilts on the tree branches; and when I got to the university campus, I often saw the quilts being taken out to dry under the dormitory building.

Every time the quilt is sun-dried, we feel that the quilt has a unique "sun smell", giving people a comfortable warm feeling. But sometimes we also wonder why only the quilt has this "sun smell", other things do not. Could it be because of mites?

The mites on the quilt

The mite has always been a known but unseen presence for us, ordinary people. If you want to visually see what it looks like, you can only observe it through a magnifying glass, because under normal circumstances the size of the mite is only between 0.1mm and 0.5mm.

Because of its delicate size, it is impossible to eliminate it even if we know it is a pest that affects us greatly, especially when society is not as advanced as it is today.

Generally speaking, there are two types of mites that we are most often exposed to, dust mites and worm mites.

Crepuscular mites are usually found in the hair follicles and sebaceous glands of humans and mammals, with more than 140 species, feeding mainly on sebaceous gland secretions or cellular metabolites and keratin.

The dust mites are divided into dust mites and house dust mites, and the mites in our quilts are the second kind. In addition to our quilts, house dust mites are also found in clothing and carpets.

They are pervasive with their tiny bodies and are called by human body heat to come down to the quilt in the dead of night to feed on the dander shed by the human body. The "sun smell" that comes out of the quilt is the smell of the mites being burnt.

Mites have nothing to do with the "sun smell"

From the perspective of mites, it is really difficult to produce the "sun smell" that we like.

First of all, the temperature of the sun does not scorch them. Mites like a warm environment and are indeed disturbed by sunlight, but they need to reach a certain temperature to be scorched. If you want to scorch them, perhaps only this summer will be eligible to try.

Secondly, the main components of the mite's body are water and protein. If it is the smell of mites being roasted, it should also be the smell of proteins being burned. In our life, if you want to know the taste of protein, you can directly burn hair. The smell with a little burnt odor is very different from the smell of the sun.

We can also exclude it from the comparison of taste.

In addition, there is a mite activity track on the quilt. Although the sun cannot scorch them, it is enough to make the mites dehydrate under heat. Therefore, when one side of the comforter is exposed to the sun, mites will hide inside the comforter. So we always turn the quilt over every once in a while so that the sun can rain on it.

In this way, the mites will try to flee to the lower temperature, and even if it is scorched, its smell will be distributed in patches, not everywhere.

These three aspects are enough to dispel our doubts about the mite carcasses. But the much-loved sun smell, what is it?

Scientists' test: it may be related to photochemical reactions

To figure out the source of the "sun smell", scientists are also quite concerned. Two years ago, Professor Johnson of the University of Copenhagen on this "sun smell" test.

First, they selected three unused and unwashed solid-colored towels, trying to avoid the influence of other factors on the experiment. Then, they chose three different locations for the test, three locations are outdoor direct sunlight, outdoor shade, and indoor.

However, only two of the towels in these three locations produced a "sun smell". This indicates that the "sun smell" has a direct relationship with the sun.

After that, to clarify the composition of the "sun smell", Professor Johnson and others put the towels into a closed device, so that the substances attached to the towels fell off, to facilitate the analysis of these substances.

At the same time, to make the final test results more obvious, the scientists also collected the material attached to the towel without the sun for comparison.

When Johnson et al. compared the spectra of the two, they found that new substances, such as aldehydes, ketones, carboxylic acids, and other organic compounds, appeared on the sun-dried towels. The smell produced by these compounds was all very pleasant and the fragrance was stronger, requiring only a small amount to be detected.

Therefore, the towels are exposed to sunlight to produce new substances and give off a pleasant smell. So how are these substances produced?

Scientists classify it as a photochemical reaction, which means that substances can be exposed to light to produce a series of chemical reactions, such as the yellowing of white shoes and the fading of dyes that we see. When a textile such as a towel comes into contact with sunlight, a series of oxidation reactions occur on its surface, eventually leading to the creation of new organic compounds.

Similarly, our favorite "sun smell" may be the quilted textile or human sebum, or other things stained on the quilt, and the sun's chemical reaction and emitted smell.

For the sunlight component, people are more inclined to be the role of ultraviolet light. With the development of science and technology, mite removal has become easier and easier, even without sunlight. Not only that, some hospitals use ultraviolet light to disinfect empty wards, but the wards also smell like the sun.

Thus, it is likely that ultraviolet light is the main source of the "sun smell".

In our daily life, mites are inexhaustible, but to a large extent, they can "live in harmony" with us. Therefore, there is no need to be too alarmed by mites, provided we pay attention to cleanliness and hygiene. The fact is that you can find a lot of people who are not able to get a good deal on a lot of things.