What are the characteristics of space food?

In the process of space orbit flight, all kinds of objects in the spacecraft, including people, are in weightlessness, and the original concepts such as orientation and weight on the earth have lost their original meaning and are in a state of free floating. Dry powder food will float in the cabin and be inhaled into everyone's respiratory tract, affecting health; Falling into the equipment will affect the function of the equipment. Therefore, different special requirements are put forward for the processing, weight and volume of space food.

The basic requirements of space food are: first, try to eat less coarse grains, because coarse grains are not easy to digest; Second, high absorption rate, less residue, light weight, small volume and rich nutrition; Third, it must be stored at 37.7℃ for 6 months without decay and deterioration; Fourth, it must conform to the astronauts' eating habits and tastes, which can arouse their appetite and eat happily.

Space food has undergone a series of evolution and improvement from simple to complex, from distortion to simulation, and great changes have taken place.

Although the astronauts' food is rich and varied, they still complain about the bad taste of the food and report to the ground control center that the taste is unpredictable, sometimes sweet, sometimes lacking the proper taste of the food, and sometimes even tasteless.

Why do astronauts' tastes change so much in space? This problem has attracted the attention of scientists, because the study of this problem will help to understand the influence of space environment on human central nervous system.

As early as 1973 and 19744, NASA scientists studied this problem in the "Sky Lab", but they did not get satisfactory results.

1984 10 10 In October, American and Canadian astronauts jointly conducted space science experiments on the space shuttle Challenger. One of the experiments is to reveal the mystery of taste change in space. Canadian astronaut Mark Cano measured the saltiness, sourness, sweetness and bitterness of the space shuttle before takeoff, during flight and after landing. Considering that people's olfactory nerves can also affect the sense of taste, Kano also measured his sense of smell for vanilla, lemon juice, spearmint and clear water in these three stages. The experimental design is very detailed.

But unfortunately, this experiment failed to uncover the mystery of taste in space. On the contrary, some scientists believe that the mystery has not been uncovered because there is something wrong with the experimental method. Because people's sense of taste varies from person to person, it is doubtful whether the data measured by a single astronaut from himself is reliable and universal.

Astronauts in the former Soviet Union also encountered the problem of stale space. Because they have worked in space for hundreds of days, they are more susceptible to taste changes. Therefore, scientists in the former Soviet Union conducted more detailed and in-depth research. Their advanced electronic taste tester measured the taste changes of astronauts in space, but they did not reach a clear conclusion.

Without convincing experimental results, scientists can only speculate on the mystery of taste changes in space. Most scientists believe that under weightlessness, the blood in the human body will flow upward, which will make the nasal cavity congested and lead to the inactivation of the taste nerve. A few scientists believe that the air flow in the space shuttle cabin is different from that on the ground, which is the real reason for the taste change of astronauts. Some people even speculate that weightlessness has affected the saliva secretion in astronauts' mouths, thus changing their taste.

Because the mystery of taste change in space has not been solved, NASA can only help astronauts improve the taste of space food by providing more condiments.