Indian astronaut Shubhanshu Shukla has been in space for more than a week, and would have had several meals during this period. On Friday, Shukla said he had shared the food he carried to the International Space Station (ISS) — gajar ka halwa, moong dal ka halwa and aamras — with other astronauts onboard.Having a meal in space is not a piece of cake. It requires planning and organisation. But this does not mean that astronauts eat frugally or depend only on liquid diets. The food is also far from being bland or unappetising.In fact, on the ISS, the permanent space laboratory where Shukla is currently staying, astronauts often enjoy elaborate meals. It is just that they eat packaged food, which is stored and prepared a little differently.How astronauts eat in spaceDue to zero-gravity conditions, food items, like everything else in space, tend to float around. This necessitates a level of organisation not required on Earth.The spacecraft’s safety could be compromised if small crumbs or loose pieces get stuck in some of its critical parts. These can also enter the mouths or nostrils of astronauts, leading to choking or creating breathing problems. As a result, food items are carefully chosen and properly packaged.The act of eating itself, that is, food travelling inside the body’s digestive tract, is not a problem. While gravity might help this process on Earth, it is not a necessity. Put simply, only management of food is an issue in space.Astronauts consume packaged and processed food items, which are usually in dehydrated form. They inject hot water through a needle into the packages before eating the dishes. Shukla’s gajar ka halwa and moong dal ka halwa — prepared and packed by the Indian Space Research Organisation (ISRO) and the Defence Research and Development Organisation (DRDO) — would also have been in this form.Story continues below this adBeverages such as tea, coffee or juices, and Shukla’s aamras, are usually in powder form, which can be mixed with water before consumption. There is provision for heating the food on the ISS.Astronauts on the space station usually have their breakfast and dinner together. Before eating, they secure themselves with footholds to restrict movement. Every astronaut has a food tray with some utensils, including spoons and forks. The cutlery and food packets are fastened to the tray with velcro. Astronauts are advised to snip open only a small part of the package, and dip their spoons inside to pick the food out.Seasonings such as salt and pepper are available, but they are typically dissolved in water which can be added to the food through droppers.After their meals, waste such as food packets is deposited in waste chambers, while cutlery is cleaned with wipes. Utensils cannot be washed with water.Story continues below this adA variety of food choices are available, and astronauts can select their menu or favourite cuisine months ahead of their travel. Once they have made their selection, nutritionists also weigh in with their recommendations to ensure astronauts meet the dietary requirements in space. For instance, astronauts need more calcium, and less sodium and vitamin D to keep their bones healthy.Such food arrangements for astronauts are relatively new. Early space travellers had to make do mostly with food paste, packaged in toothpaste-like tubes or bite-sized cubes. When confined to a spacecraft, like during the journey to the ISS, these forms of food are still useful due to space and storage constraints.Why grow food in spaceDespite technical advancements in packaging, storing, and preparing food items, scientists are now actively working on ideas for growing food in space. This is because, in recent years, astronauts have begun spending a lot more time in space.For example, those going to the ISS typically spend a few months at a time. Due to this, all their food requirements are not transported on the same spacecraft that carries them. Cargo missions to the ISS fly at regular intervals, carrying food, apart from other requirements such as maintenance gear and scientific equipment.Story continues below this adAlso, various space agencies and private companies are now planning even longer stays in space, including the possibility of creating a permanent settlement on the Moon. There are also plans to travel much further distances than ever before in space — on such missions, it might not be economical to supply food from Earth.Space-grown plants, for example, can provide a sustainable food source for such missions. Scientists are currently studying different aspects of growing food in space, and exploring various methods to do so. For instance, they are examining the effects of microgravity on the growth of plants.They are also making attempts to use LED lights to induce photosynthesis. Researchers are developing soilless systems in which plants can be grown in space, and selecting crops most suited to grow in these conditions.Potatoes, soybean, wheat, spinach, tomatoes, and carrots are some crops that have shown promise for space cultivation.Story continues below this adISRO is carrying out multiple experiments related to this subject during Shukla’s stay at the ISS. At least six different varieties of crop seeds will be grown and studied. There is a separate experiment on the growth of microalgae as well. Besides food, these microalgae can be used as potential fuel or even used in life support systems.