The production of meat substitutes has grown in recent years, driven by the high demand for food in the world and a greater number of adherents of restrictive diets of animal proteins. According to a study published in the scientific journal Nature, livestock production has more than doubled in recent decades and corresponds to 80% of the world's agricultural land, if considered the pasture fields and plantations for animal feed production. The substitutes intend to offer a sustainable alternative in this scenario.

With the significant increase in livestock, it is the environment that is felt, since this type of production is one of the main contributors of greenhouse gas emissions, such as methane. According to the United Nations Environment Programme (UNEP), livestock emissions about 32% of the total methane emissions in the world – from manure and gastroenteric releases of animals.

To placate the situation, substitutes have been gaining space and the most found in the markets are planted based, or plant-based. These products are present in the form of hamburgers, meatballs, nuggets, "meats" with sauce, such as stroroonoff or mincemeat.  According to food engineer Ana Lúcia Lemos, director of the Meat Technology Center (CTC) of the Food Technological Institute (Ital) in Campinas, "these products will provide a very interesting texture, very similar to that of animal meat." She comments that they supply animal protein nutrition well, but lack other essential nutrients such as vitamin B12, iron and zinc.

The director of the CTC also draws attention to tertiary nutrition, which are other less publicized compounds, such as conjugated linoleic acid present in animal meat and which has numerous health benefits. There is also carnosine and carnitine, which are peptides present in meat in large amounts and have numerous benefits in strengthening the immune system and gaining muscle mass. These compounds are not found in foods of plant origin, for example.

New technologies

Conventional meat production in the world seems to be without much room to expand, which may lead industries to seek innovative alternatives. A new process under development is to replace animal meat with so-called mycoproteins, an alternative source of proteinstemming from the culture of filamentous fungi, as professor Felipe Chambergo, coordinator of the postgraduate degree in Biochemistry and Molecular Biology at the School of Arts, Sciences and Humanities (EACH) of USP in São Paulo, explains.

According to Chambergo, the fungus used is Fusarium venenatum. Foods processed from it have high protein content, are high in fiber and contain low saturated fat content, and are commonly used as a vegan or vegetarian alternative to animal protein. "The fungus is grown in a fermentation process, after which the micellar mass is harvested, drained, frozen and textured. A flavoring and processed is added to become an analogue of ground beef, fish bait, skewers, nuggets, among other presentations of the taste of consumers," comments Chambergo.

Mycoprotein is also a substitute for foods based on plant proteins, such as peas, soy or wheat, for people who are allergic or on diets with restriction of this type of food. Companies around the world are exploring the potential of mycoproteins to develop innovative ingredients and additives for the beverage and food industry. In Brazil, there is still no production and marketing of products containing mycoproteins.

Laboratory meat

Another innovative proposal is the production of in vitro meat, that is, produced in the laboratory. According to Professor Viviane Nunes, specialist in the area of Cellular Physiology of Skin and Tissue Bioengineering at EACH/USP in São Paulo, the technology developed so far still does not solve the use of animal products for cell cultivation in both proliferation and differentiation. This technology has not yet been able to describe the supports used for three-dimensional cell cultivation, a model that facilitates cell proliferation, and how it will dispense with the use of antibiotics used during the cultivation period.

Regarding food security and nutritional composition, "in vitro meat should make up the menu of foods suitable and available to the population, however, there are still few studies in this area. Our group intends to evaluate the nutritional composition of the product aiming at adequate cell cultivation to obtain specific nutrients or to indicate the need for any nutritional supplementation", comments Viviane.

The environment

According to Viviane, what is said is that the production of meat in the laboratory on a commercial scale, without the slaughter of animals, can lead to a savings of 50% in energy consumption, about 99% reduction in land use, 90% reduction in water consumption and 80% less greenhouse gas emissions. However, much study still needs to be done to demonstrate the sustainability of the process, such as the quantification of garbage, such as plastics and other waste that is generated during production.

"Although there is a concern about aspects related to sustainability, it must be shown that cultivated meat will indeed be a sustainable product in the short term. Obviously the improvement of technology, which can take up to decades, should contribute to meet this criterion", says Viviane.

Economic advantages

According to Professor Sérgio Bertelli, from the Faculty of Food Engineering at Unicamp, substitutes "are much more expensive than chicken meat and even beef; a kilo of vegetable hamburger comes to cost on average R $ 100, while a kilo of beef ground meat is about R $ 35. If you think about cultivated meat, the value should be close to R$ 5,000 a kilo, using estimated values of productions outside Brazil."

It is believed that, with the increase in large-scale production, this price will decrease. But initially, the development of technology and the construction of bioreactors that meet a growing demand need major investments. "Equally, appropriate amino acid and growth factor formulations are not currently produced at scales consistent with food production and their projected costs are equally high, so it is critical that production volume is high and costs are decreased, but this requirement has not been achieved by far," viviane says.

Speaking about replacing the mode of meat production, Bertelli states that "a world without meat may seem simple, but it is not." According to the professor, cattle, goats and sheep transform the pasture or residue of other industries into nutritionally rich foods, such as meat and milk. It also draws attention to a number of animal by-products that feed a vast network of other industries such as leather, blood, kids, manure and animal feed flours.