What to eat during space travel? Artificial food may become the mainstream in the future

As the saying goes: "Three meals a day, life is a necessity", we need food to live. In the past, our food mainly came from natural resources that can be eaten directly or indirectly, such as cereals, potatoes, vegetables, fruits, meat, eggs, milk, fungi and algae. For thousands of years, we have been accustomed to this diet. Have you ever thought that one day in the future, our food may be created?

Friends who love space science fiction movies must have noticed this scene: people in outer space rely on artificial staple foods and meat to sustain life. In reality, some scientists believe that food is an important factor restricting human conquest of space. The good news is that this problem is gradually being solved. Nowadays, cell-cultured meat, synthetic biological milk, and nutritionally fortified recombinant rice have gradually come out, and there may be more artificial foods in the future.

What are artificial foods?

Artificial food is also called bionic simulated food. As the name suggests, it is a new type of food that is made by scientific means from raw materials and tastes similar to natural food.

Artificial food is not fake or inferior food. When it comes to artificial, many people will think of fake and inferior food made by a few lawless elements using technical means, such as the rice and seaweed made of plastic that have been reported before. Artificial food is just as edible and nutritious as traditional food. The difference lies in the different ways of obtaining it. Therefore, the safety of artificial food can be fully guaranteed.

How are artificial foods made?

The manufacture of artificial food is a combination of bionics principles and modern technology. First, it is necessary to determine the shape and structure of the food to be simulated, especially considering the purpose, taste, color and other factors of the food. Secondly, prepare the corresponding raw materials according to the needs, such as plant fiber, starch, sugar, etc., and screen and process them. Thirdly, use the corresponding technical means to manufacture food. For example, 3D printing technology and microbial fermentation, etc., different food manufacturing methods are slightly different.

Take artificial meat as an example, it can be divided into two types. One type of artificial meat is also called plant protein meat, which is mainly made from soy protein because it is rich in protein and a small amount of fat. The other type is cell cultured meat made from animal stem cells, and meat obtained by this technology has attracted more attention.

In 2012, Dr. Mark Post, a scientist at Maastricht University in the Netherlands, finally succeeded in cultivating cell-cultured meat for the first time in the world. He first extracted a small piece of meat from a living animal, then filtered the muscle tissue and separated it into muscle cells and fat cells, and then placed the required muscle cells in a culture dish and added serum for cultivation.

The serum provides the muscle cells with necessary nutrients, such as amino acids, vitamins, carbohydrates, etc., giving the cells the feeling of still existing in living tissue. The cells use the various nutrients in the culture medium to replicate and proliferate. As the number of cells increases, they form bands, just like natural muscle cells forming fibers in living tissue. The final tissue is like processed boneless meat, and we finally get the cell-cultured meat we want.

Unlike artificial meat, artificial milk uses 3D printing technology. First, the DNA sequence of the cow is printed out and then inserted into the DNA sequence of yeast. Then, casein, lactoprotein and lactoglobulin are obtained through yeast fermentation. These proteins are then mixed with plant nutrients and fats to finally obtain a liquid food similar to milk. The nutritional value of synthetic milk is not much different from that of ordinary milk, but the shelf life is significantly longer than that of ordinary milk.

What are the advantages of artificial food compared to traditional food?

Artificial food increases the ways to obtain food, shortens the production cycle, and has a broader application prospect. Due to geographical, seasonal, climatic and other conditions, the acquisition of traditional food is somewhat limited. For example, even the most high-yielding rice is affected by meteorological conditions and pests and diseases, and the yield cannot be stable. Artificial rice is different. The use of edible fungi to ferment coarse grains can be done regardless of spring, summer, autumn and winter, and there is no need to worry about rain, snow and hail. Artificial rice can be obtained in just 3 to 4 months. For example, the production of artificial meat can be completed in laboratories and factories. No feed is required in the whole process, which not only improves efficiency, but also is not restricted by the scene. It is very suitable for space travel and harsh natural conditions.

Artificial food can improve the nutritional content of food and enhance the nutritional value of food. Whether it is artificial milk, artificial meat or artificial rice, their starting point is based on the nutritional composition and taste of traditional foods, and they are replicated and imitated by means such as synthetic biology. Not only are most of the nutrients consistent with traditional foods, but they can also be appropriately changed according to human needs. For example, human milk oligosaccharides that can regulate intestinal flora are added to artificial milk during the production process. During the production process of artificial meat, it is also possible to control what kind of fat is allowed to enter it to make it more beneficial to human health, such as adding omega-3 fatty acids that have heart-protecting effects. Therefore, from the perspective of nutritional content, artificial food can make it more nutritious and is expected to be superior to nutritional fortification and genetic modification technology.

Will artificial food replace traditional food in the future?

Artificial food and traditional food will be the main source of nutrition on our table. Even if the nutritional content of artificial food is not much different from traditional food, and it is expected to be produced at low cost and in large quantities in the future, it still cannot replace traditional food in terms of flavor and people's long-standing food culture.

The identification of ingredients and functions in food requires time and process. With the continuous development of modern food analysis technology, we have a relatively clear understanding of the types and contents of the main nutrients in food, but some ingredients in food and their functions have not been fully studied in depth. For example, in the past, we believed that dietary fiber was "garbage" that humans could not absorb and use, but with the recognition of the importance of intestinal microorganisms, the importance of dietary fiber has gradually become clear, and it has even been classified as the seventh nutrient.

Take artificial milk as an example. Many people believe that 87% of milk is water, and the rest is protein, carbohydrates, fat, vitamins and other substances. In fact, in addition to basic nutrients, there are many active substances with extremely low content but biological effects, such as biologically active β-lactoglobulin, α-lactoglobulin, lactoferrin, immunoglobulin, etc. At present, our scientific research has not yet fully figured out how many kinds of biologically active substances are in milk and what role they play. From this perspective, artificial milk can only be a simple imitation of milk, and cannot be a real substitute or surpass.

In what areas will artificial food be used in the future?

Artificial food technology is a very important step in the process of human cognition and transformation of the world, and it is of great significance to the future survival and development of mankind.

On the one hand, the world population will still face a huge food gap in the future. The world consumes a total of 1.2 billion tons of food each year. Although the world's total food production has increased year by year, with the continuous increase in population and the frequent natural disasters caused by global climate change, these factors will affect global food security. In the face of these problems, people around the world are actively responding through various means, from regulating population growth to actively looking for new sources of food, but they are still unable to cope with food security issues. Therefore, artificial imitation of traditional food is a development direction for future food. If one day, the earth really becomes resource-depleted, it seems that only artificial food can truly solve all problems.

On the other hand, artificial food is conducive to human exploration of space. Just like the movie "The Wandering Earth", when traveling in space, the problem of logistics supply is the most serious. Artificial food can be based on synthetic biology technology to produce the required food using organic and inorganic substances in a very limited space. Whether it is staple food, meat or milk, it can be solved. It not only satisfies nutrition, but also provides a suitable taste. The most important thing is that it is convenient to supply and can be produced under specific conditions. Just imagine, isn't it a beautiful thing to drink a cup of hot milk, eat a sandwich, and admire the stars in outer space while flying in space?

What other artificial foods are worth looking forward to in the future?

Artificial food technology can be used in many aspects. As long as there is demand, there will be output. For example, vegetarians can look forward to the emergence of plant-based meat. Different from traditional vegetarian meat, plant-based meat can be made from bean protein, water, brown rice, coconut oil, beet juice and potatoes, etc., and is similar in appearance and taste to meat, with almost the same nutritional value. Of course, the same technology can also be used to make plant-based fish, cell culture technology to make more meat products, and 3D printing technology to make more foods, even meat products.

How long will it take before we can eat artificial foods?

There are still certain barriers to the manufacture of artificial food, and it cannot be supplied in large quantities in the short term. Taking cell-cultured meat as an example, it has been proven that the use of muscle for in vitro proliferation under sterile conditions is technically feasible, but the scale is still small. On the one hand, although we can imitate the environment required for cell growth and provide sufficient nutrients, the stability of cells cultured in vitro is still poor. Cell metabolism, self-repair functions, etc. will be affected, so all cells will undergo some changes in the process of in vitro culture to a greater or lesser extent. On the other hand, after cells have been cultured in vitro for more than 15 generations, the possibility of cells mutating and transforming into tumors is very high, but the value-added capacity of muscle cells themselves is limited, so late-stage cells must be used in the cultivation process, and the use of such cells can only produce two results, one is that the aging cells die, and the other is that the cells become cancerous, all of which increase the uncertainty of in vitro proliferation.

However, the emergence of any new technology may have two sides, and while it is being used, it must also be well controlled.

In his science fiction novel "Eternal Food", former Soviet writer Belyaev described that in the future, people will use fungi to create "eternal food". As long as it is placed in the air and exposed to sunlight, it will grow by synthesizing oxygen. Moreover, it tastes like jam. After the hunger problem was solved, other problems arose. "Eternal food" was everywhere, causing food prices to plummet and farmers to go bankrupt. This also sounded a wake-up call for us. While artificial food technology is popular in the future, whether it will have an impact on the traditional food industry should also be considered in advance.

No matter how artificial food develops in the future, it is an inevitable trend. While we are optimistic, we still need to remain cautious.

This article is a work supported by Science Popularization China Starry Sky Project

Author: Zhang Yu

Reviewer: Tan Yuqing, Associate Professor, College of Food Science and Nutritional Engineering, China Agricultural University

Produced by: China Association for Science and Technology Department of Science Popularization

Producer: China Science and Technology Press Co., Ltd., Beijing Zhongke Xinghe Culture Media Co., Ltd.