How do mealworms multiply

How to grow mealworms in the kitchen

Two young industrial designers took seriously the UN's call to eat more insects and developed a device that can be used to breed mealworms.

It may take some getting used to. Because up to now, mealworms have primarily been about how to drive them out of the kitchen and what to do to prevent the annoying pests from coming back. Two young industrial designers have now turned the tables and spent years researching how to get mealworms to reproduce in a controlled manner in your own four walls in order to then eat them. After all, the FAO, the Food and Agriculture Organization of the United Nations, has been pointing out for years that Western societies should also eat insects to avoid food shortages, but also to protect the environment. The UN is still sticking to this goal, even though it declared 2016 the year of legumes, which is also an excellent source of protein and therefore a meat substitute.

Katharina Unger and Julia Kaisinger have been dealing with insects for a long time. On Thursday they presented the prototype of their Livin Farms Hive, a mealworm breeding station, in Vienna.

“It all started with my diploma thesis at the University of Applied Sciences, where I developed a device that can be used to breed the black soldier fly,” says Unger. She was surprised by the positive feedback that followed on the Internet. “A lot of people got in touch and wanted that too. That really worked. ”So she developed the idea further. Unger - who grew up on a farm in Burgenland - was then in Hong Kong for a year to do research. At the beginning of 2015 she founded Livin Farms together with her colleague Julia Kaisinger.

Instead of the soldier fly, they have now focused on the mealworm. Unger was fascinated from the start by the sustainability and the low effort with which the protein supplier can be grown. “Of course we should eat more vegetables, but that also requires a lot of water and soil.” Insects, on the other hand, need comparatively few resources. The project was financed through the crowdfunding platform Kickstarter. The funding target of $ 100,000 has already been exceeded, and around 200 people from the USA, Canada, Europe and Asia have ordered the device. At the start of the campaign, it was available for $ 499. Yesterday, Saturday, the Kickstarter campaign was ended, after which the production of the devices will start. The first hives will be delivered in autumn.

The life cycle of the mealworm. The hive looks like a white tower with lots of drawers. All life stages of the mealworm have space in it, which means that the mealworm farmer has the life cycle of umpteen small mealworms on his kitchen table. “It was also about showing that you can breed insects cleanly and hygienically.” In fact, you can neither smell the small farm, nor is there an opportunity to try to escape anywhere.

The life of mealworms is from top to bottom. Right at the top, in the first ark, are the beetles, the parents of the mealworms, so to speak, which are the mealworm larvae. The flour beetles live and mate in this “love chest”. Thanks to a fine grid, the eggs fall into the container below and hatch to the mealworm babies. In the next store they grow up gradually. “One week is a stage of development. You can harvest the mealworms in six weeks. "

Waste as flower fertilizer. So in the six shops in which the worms grow, they are fed by opening the drawer and throwing in old bread or kitchen rubbish. After a week, the top mealworms are transported to the next drawer using a lever. The oldest mealworms that can soon be harvested are in the bottom drawer. The faeces of the animals and fine dust particles are filtered out by means of a sieve. “You can use this to fertilize the flowers, for example,” explains Unger. In the bottom drawer, the “harvest drawer”, there are the fully grown mealworms, which are then harvested.

In between there is a small catch basin for particularly precocious mealworms, i.e. those that pupate particularly quickly. Because of their size, they do not fall into the harvest drawer and are simply placed in the first drawer using a grid. There is a small elevation there that the beetles cannot reach, on which the pupae are placed. If they slip, the little beetles crawl down into the "love drawer" and can multiply there. The beetles die of natural causes after a few months and are removed by taking out the drawer and shaking it vigorously - “then the living beetles hold onto the grille, and if you turn it around, you can just throw the dead beetles away . "

In the bottom drawer, the finished mealworms are harvested by placing them in a freezer bag and freezing it. So the animals die a relatively natural death. After about an hour, the worms can be removed and processed. Unger and Kaisinger harvest around 200 to 500 grams of mealworms per week. “That corresponds to four to five meat meals,” says Unger.

The mealworms can either be boiled in hot water, roasted - to eat them like chips - or generally processed like meat. They are relatively tasteless and have a slightly nutty taste. To present the prototype, the two prepared quinoa mealworm balls, salads with roasted mealworms or brownies with mealworms. Unger admits that in the beginning it takes some effort to eat the animals. "It was really strange for me too." In the meantime, however, she has even been able to convince her family. “She was totally shocked at the beginning, but now she's thrilled. My mother cooks with it a lot. "


The FAO, the World Food Organization U.N, In view of the increasing world population, advises that western nations also eat insects. Insects have a high protein, fat and mineral content and can convert two kilograms of food into one kilogram of insect mass. Cattle need eight kilograms of feed to produce one kilogram of body mass.

("Die Presse", print edition, January 10, 2016)