Edible insects on our dining tables: a superfood that has earned the approval of great Michelin-starred chefs and has now become a trendy street food. Their consumption is also promoted by the United Nations as a possible way of combating the world food shortage. In brief, crickets, grasshoppers, spiders and the like are a new form of planetary nourishment, as well as a culinary trend so widely diffused that it has led to food fads of all kinds: scorpion pizza, fried tarantula spiders and bee larvae ceviche are considered by connoisseurs to be the new gourmet delicacies.
But are insects – the food of the future – really the solution to world famine, as we hope they will be? To answer this question and understand whether they are likely to become an effective new model of nutrition, researchers from the University of California in Davis, Usa, have studied the footprint left on the environment by the rearing and consumption of these protein-rich foods.
Their study (Crickets Are Not a Free Lunch: Protein Capture from Scalable Organic Side-Streams via High-Density Populations of Acheta domesticus) published this spring in the science journal Plos ONE has quantified the utilization of resources and pollution that would result from hypothetical cricket farming methods, based on the type of diet the insects are reared on. The study concludes that, as yet, insects may not be considered the key to solving the problem of how to nourish the world’s 9 billion inhabitants in 2050 and that, in some cases, their “protein conversion” ratio would appear to be almost equivalent to that of chickens.
The first assumption on which the researchers have based their studies is that, similarly to all other sources of animal proteins, insects need to grow and be fed before they can become a food source themselves. In the course of the experiment, crickets were reared on five different diets: starting from a diet based on grain, soy and mixed seeds to one entirely consisting of waste products.
In this way, the researchers were able to demonstrate to what extent the insects’ diet is a fundamental variable impacting their size and protein content. Those reared on prime quality seeds grew bigger and offered a higher feed conversion rate (the so-called protein conversion ratio) than those fed on food waste and poorer quality seeds. The latter revealed a lower protein output than that of the farmed meat available on today’s market, whilst some did not even survive long enough to become food. But even in the family of crickets reared on prime quality seeds, the protein conversion ratio did not appear to be so efficient either: it stands at around 35%, a value that is just slightly higher than that of chicken. So, bearing in mind this documented fact, the farming and consumption of insects would not seem to offer greater benefits than a diet of poultry, at least from the nutritional viewpoint.
This does not mean, however, that insects should not be considered an equally important opportunity for our planet’s future: from an evironmental point of view, they need less water to grow and reproduce and they produce less gas emissions than other animals. However, there is still a long way to go before they really become a superfood: a lot of progress still has to be made in terms of technology and research, to study a model of development and farming which is both environmentally friendly and able to solve the problem of world nutrition. Without forgetting the tastiest aspect of this issue, because the insect revolution first broke out in kitchens around the world.