Internationally known, açaí is a fruit with rich nutritional values, such as vitamins, antioxidants, fats and proteins. Consumed as food both outside and inside Brazil, the plant extraction in the country is entirely concentrated on the açaí plantations within the Legal Amazon area, which totaled more than 220,000 tons in 2020, according to data from the Brazilian Institute of Geography and Statistics (IBGE).
In addition to being part of the food culture in the Northern region, açaí serves as a source of income for many families, from extractivism to pulp sales points in cities. Given its importance to the region, scientists have discovered other possibilities to take more advantages of the fruit versatility. At Federal Rural University of the Amazon (UFRA), located in Pará, a leading state in the extraction of açaí, the use of the seed to replace wood in the generation of clean energy and bioproducts is being studied.
The research was coordinated by Professor Lina Bufalino, from São Paulo who has previous experience with the creation of bioproducts stemming from sugarcane and corn bagasse fibers, among others. “Fiber is a cell, found in the plant, which is very resistant, does not degrade easily, and lasts for a long time. We’ve noticed that everything containing fibers could be employed to replace wood. If we make MDF with wood fiber, why not make it with fiber from other materials?”, she contextualizes.
In the North region, the Professor observed the consumption of the fruit in the Brazilian Amazon is mainly by way of the artisanal production of liquid pulp, available at various sales points in the cities. After the liquid is removed, what remains is the residue, the seed, which is often discarded in sacks, in large quantities, and taken to landfill dumps.
“When I noticed this residue, the first thing I observed was the large quantity of fibers, those ‘little hair strands’ around the açaí seed”, recalls Lina. The aspect drew attention because every fiber has great potential to generate bioproducts. “It has the potential to make charcoal, MDF, paper and other bioproducts from this fiber”, she adds.
But, in addition, the seed showed potential for bioenergy – energy obtained from biomass, which is organic matter of plant or animal origin. In the project, the biomass would be the açaí seed, which, when submitted to combustion, has its chemical bonds broken and can generate thermal or electrical energy. The first step was to evaluate the bioenergetic potential of the seed itself. “We believe that a single unit of waste has a high density of stored energy. And the seed has an interesting shape for this use, as it is small and easy to transport”, she informs.
According to Professor Bufalino, the characteristics of açaí seeds are very similar to those of eucalyptus, the main raw material used today for the production of charcoal in the region. This way, the residue would no longer be a simple garbage to be burned in ovens, as in pizza places, replacing firewood and charcoal. “A slight disadvantage we have observed, compared to charcoal from eucalyptus, is the ash content, which is higher in açaí seeds, but we are already working to see how to get around this”, she ponders.
She also refers that, currently some potteries already use the açaí seed as a source of energy, in an amateur way. But the objective now is to stimulate the research progress so that innovation can be taken on an industrial scale. For this purpose, it is necessary to carry out more tests to fully understand the limits and better conditions of the resource use. Therefore, one of the specificities that the research group is currently analyzing is whether the inadequate storage of açaí seeds (bagged in exposed locations under the sun and rain) affects the properties of the residue.
Fruit fibers may turn into sustainable packaging
When studying the potential use of the fibers (the “hairs”) of the açaí seed, the research group also created nanopaper, a type of plastic film, by isolating the cellulose, one of the components of this raw material. According to the professor, this film can be applied to sustainable packaging, and even “smart” packaging, which is able to change color if the food rots. “All this has a lot of potential, we have already created the prototype, now we are studying to move forward. What we are going to do now is try to improve, in a more intense process, mixing other components to see if the characteristics of this fiber change”, she explains. The project team involves students and partner professors from UFRA and from the Federal University of Lavras, in Minas Gerais, where the team uses the equipment to make nanofibers.
The professor points out that taking advantage of these açaí seeds that would be discarded brings not only possibilities of having a cheaper raw material, but also benefits to the environment. “If this inappropriate disposal ends up in rivers, it causes silting. If it accumulates in garbage dumps or on the streets, it degrades the environment by emitting carbon dioxide into the air. Besides, it can also attract venomous animals”, she explains.
Researchers seek matchmaking with startups
After the initial phase of the research, which proved all these potentials of the açaí seed, the team's laboratory is currently undergoing an expansion, so that it can become a reference center and act together with the market. “Startups, for example, are paying attention to this potential of açaí, to transform what we research into a commercial reality”, points out the professor.
At the moment, the team is even partnering with a company to generate a cement slab reinforced with açaí fiber. “Again, açaí would replace wood and this slab could be used to make flooring and ceiling lining. This blend represents a great advantage in a hot region like ours, because it is much more resistant to termites and humidity”, she says. Currently, the team is in the process of perfecting the process in order to comply with commercialization standards.
“My main goal now is to produce paper and nanopaper. We have already accomplished some researches and the results are promising. When partnering with a cosmetics company, a soap made from an Amazon raw material could already be sold wrapped up in a paper made from açaí”, she exemplifies. “Thus, we can replace what comes from oil, both energy and plastic, for sustainable sources, which would be much more ecologically correct”, she states.
The new utilities can also generate income for the community, from collecting açaí seeds at points of sale to separating the fiber from the seeds, in addition to direct and indirect jobs generated by the industry.
Açaí seeds turned into animal feed
The use of açaí seeds to feed pigs was tested in the south of Amazonas, the second largest state in açai extraction in Brazil. The research, published in 2020, was carried out by a multidisciplinary team of professionals from the Federal Institute of Amazonas (IFAM) and the Federal University of Amazonas (UFAM), belonging the fields of veterinary medicine, agronomy, zootechnics and agriculture.
The project was coordinated by the veterinarian Idalécio Pacífico and developed in the municipality of Lábrea, in the state of Amazonas. “It is a region that produces açaí and, at the same time, there is a great lack of animal feed, because the raw materials are imported from other states, so they arrive there at a high cost, especially in the rainy season. Family farmers, unable to afford such foods, especially corn and soybeans, were already used to feeding pigs with raw açaí seeds added to a little salt sometimes,” says the veterinarian.
As such, the researchers decided to test animal feeds using different amounts of açaí seed added to their compositions. After the treatment period, no significant differences were observed compared to pigs fed with traditional feed.
After proving the potential of the açaí seed to produce alternative feed for pigs, the project was concluded. However, according to Idalécio Pacífico, it shows promising possibilities to be continued, investigating whether there are factors which can negatively contribute to the absorption of vitamins and minerals in pigs and testing this kind of diet in other animals, such as birds.
Technology developed at UFPA results in açaí powder and oil
At the Federal University of Pará (UFPA), a research group coordinated by chemical engineer Raul Carvalho Júnior, has developed the “supercritical technology” to extract the powder and oil from açaí. The initial purpose was to solve a common problem experienced by people from Pará when traveling outside the state: finding açaí of good quality anywhere, without the necessity of freezing it for transport and commercialization, preserving the characteristics of the fruit, which is so important for the Pará cuisine.
“The idea was to separate the powder and oil from açaí, preventing the bioactive components of the fruit, which are highly oxidative, from easily degrading in the presence of sunlight and high temperatures. By being able to isolate the powder and the oil, we prospected these products could be sold separately. When bought by someone and taken home, it would be possible to mix the two components together with water, then, having açaí anywhere”, he says.
However, the research results overpassed the group's expectations, since they observed several other applications for the byproducts. “Açaí oil is like a vegetable oil, including more functional properties. It can be consumed in our daily diet, inhibiting the body's antioxidants, providing omega 3, vitamin E, vitamin A. Açaí powder is also very rich in proteins, minerals and antioxidant bioactive compound, such as anthocyanin, which can be used in the food and cosmetics industries, in addition to medicinal products. But this use still requires deeper research”, explains Raul.
Raul believes that with such findings he can expand the Pará market: “currently, açaí is still sold in a very rudimentary, exploratory and extractive way, without great benefits for the riverine communities, which actually grow it. This scenario occurs because açaí is bought just to be consumed as food, the only criteria demanded by consumers is whether it is “thin” or “thick”, if it is has gone sour or not. After this technology, Pará would have the opportunity to commercialize a new benefited product, being able to negotiate directly with the industries, which adds value to the entire production chain”, ponders the researcher.
Byproducts maintain the main properties of açaí
In addition to obtaining two new products for the market, one of the main positive aspects of the research is the production process itself, since, according to the researcher, the technology developed does not produce negative impacts on the environment, as it is totally free of toxic substances and has low operating costs. “We work with the so-called 'critical point' of the relationship between pressure and temperature of a substance. In this case, we place the açaí pulp in a steel column and insert carbon dioxide, CO2, in a 'supercritical' state - a specific temperature and pressure. CO2 has the ability to penetrate the structure of the açaí and extract the fat from the pulp, resulting in the fruit's oil. Afterwards, the CO2 evaporates and, as final products, we have açaí powder and oil”, he describes.
The byproducts obtained preserve the main properties of açaí. “Açaí remains the same, however, without the oil, without the vegetable fat. That's why we call açaí powder 'fatty free'. It is a defatted powder, keeping the protein, fiber, minerals and anthocyanin, which is the substance that causes the purple color of açaí. As the elements were separated, the concentration of these substances in the byproducts are even more concentrated”, he says.
Now, the researchers are working together in partnership with a startup company in the Science and Technology Park (PCT), in Guamá campus, focusing on the manufacturing potential of the products, which have multiple applications in the industry.