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Textures and flavors

From an electronic tongue to a coffee powder analyzer, new pieces of equipment are licensed by Embrapa

Coffee consumers will be the main beneficiaries with two new technologies that are forecast to reach the market by the end of this year. One of them is an electronic tongue, an device developed to evaluate the attributes of the beverage, such as acidity, aroma, flavor and consistency, and the other is a food analyzer, used to detect impurities in samples of coffee powder. The two technologies are part of a package of five innovations developed at Embrapa Agricultural Instrumentation, a unit of the Brazilian Agricultural Research Corporation set up in São Carlos, in the state of São Paulo, licensed in December to companies specially created to transform them into products. The others are a portable tomograph for evaluating soils and wood, a photoreactor for the treatment of pesticide residues in water, and a process for transforming sewage sludge into fertilizer.

The transfer of these innovations is part of Embrapa’s New Agricultural Technology Based Company Development and Technology Transfer Support Program, funded by the Inter-American Development Bank (IDB), which started in April 2004, when an agreement was signed for a partnership in the incubation of companies with the São Carlos High Technology Park Foundation (ParqTec), to stimulate the creation and development of micro and small businesses that use technologies developed at or adapted by the institution. “As they are new products, the entrepreneurs need backing to face the technological challenges that have to be overcome to arrive at the end product, says Ladislau Martin Neto, general head of Embrapa Agricultural Instrumentation.

One trait that unites the entrepreneurs chosen is their profound knowledge and involvement with new technologies. The career of researcher Edson Roberto Minatel is very illustrative. Graduated in computing science and with a doctorate in computer physics, since 1991 he has been studying at Embrapa in the area of software development. In 1999, he achieved the first handing over of technology, of a system for analyzing agricultural spraying that he developed at Embrapa itself, in partnership with the Federal University of São Carlos (UFSCar) and the Agronomic Institute (IAC), an organ linked to the Agriculture and Supply Deparment of the State of São Paulo, headquartered in Campinas. “Today, this software is a success story, not only in Brazil but abroad as well”, says Minatel, who exports the product to the whole of Latin America and to the United States.

Two new opportunities arose with the opening up of the selection process for the technology transfer of the food analyzer and the portable tomograph. “I already knew the works, and I saw the potential of the technologies as a business.” To take part in the selection, he started Whitepix, a company that is going to take care of the necessary improvements to place the two new products on the market, and also to develop a project for analyzing ceramic surfaces, totally automated.

Photoacoustic effect
The research and development work of the food and coffee analysis system began as a challenge for researcher Washington Luiz de Barros Melo, a physicist who worked for 13 years at the Electrical Engineering Department of the São Paulo State University (Unesp) in Ilha Solteira. In 2000, the then general head of Embrapa Agricultural Instrumentation, Paulo Cruvinel, wanted to know whether the photoacoustic technique could be used to detect adulterations in roast and ground coffee powder.

By this technique, used in applications in physics, chemistry, engineering, agriculture and medicine, the photoacoustic effect arises when a beam of light hits a sample inside a closed chamber, full of gas. The light is absorbed by the sample, causing a variation in pressure in the gas, resulting from the flow of heat coming from the sample itself. This variation in the pressure, represented by sounds, is captured by a microphone inside the photoacoustic chamber. Each sound represents a different structural behavior.

In the 1980’s, the group of Professor Helion Vargas, from the State University of Campinas (Unicamp), had already done some experiments with liquid coffee, which resulted in publications in foreign magazines. Melo, in turn, had studied and tested the application of the method in conducting polymers.

At Embrapa, in 2002, Melo assembled a basic piece of equipment for analyzing samples of coffee, but, in the light of the various problems that arose, he decided to work with another technique, known as photothermal, which also uses light and looked more promising. By this method, the incandescent light from a small bulb hits the support where the sample of coffee is placed, which is made up by a small cylindrical part. The thermal wave generated is propagated by the sample until it reaches a pyroelectric sensor, made up of a metallized  polymer thin film that transforms the variation of the heat into an electric current, passed on to the electronic equipment and decoded by a computer program. The program transforms the information into graphs. “When I saw that the situation was promising with the pyroelectric detector, I went in with a project at FAPESP”, Melo says.

The parts that are in the equipment were built  in a meticulous work of a craftsman, by the researcher himself, in Embrapa’s workshop. Melo only arrived at the compact equipment, in its current format, in August 2004. From then until now, some parts were perfected, such as the part in which the sample of powder is placed. “It was modified and, with this, the pressure was distributed and the signal amplified tenfold”, the researcher says. He also developed and built a special sieve for coffee powder, which facilitated his work in preparing the samples for analysis. If the sample contains only coffee, without any impurity, the signal captured by the detector and sent to the computer corresponds only to the structure and composition of the coffee. When the material is adulterated, with straw, corn, barley, coffee dregs or burnt sugar, the signal changes completely. “Depending on the structure and composition of the medium, heat is propagated in a different manner.”

The research was done in partnership with the Brazilian Coffee Industry Association (Abic) and the State of São Paulo Coffee Industry Union (Sindicafesp). Abic is in charge of the Purity Seal program, launched in 1989, which guarantees the quality of the coffee. Although the current legislation, in force since 1938, only regards as pure coffee powder with 1% of impurity, in some brands this percentage reaches 85%. The methodology currently used for identifying adulterants uses photographic images to analyze the surface of the powder, digitally processed by software. In the case of a suspicion of adulteration, the samples are put in chloroform to remove the fat, and after they have dried, the separation of the particles is carried out. “It is a lengthy and subjective process”, Melo says.

Abic is the main party interested in the new technology. Actually, all the companies from the coffee industry have an interest, as they intend to win over more room in the market, both domestic and foreign. After all, Brazil is the second largest consumer market for the product, with 15 million bags a year, compared with the 20 million bags a year in the United States. The main application at the moment is coffee, for what it represents for the Brazilian economy, but the equipment also analyzes impurities in wheat flour, powdered milk, cashew flour and in other foods.

The other innovation passed on by Embrapa, the electronic tongue, is a palate sensor constructed of a nanostructured film with just a few layers of polymer molecules. The electronic tongue does not analyze impurities in the coffee, but the characteristics of each type of this beverage. The differences in other liquids, such as water and wine, can also be evaluated by the sensors of the equipment developed by a research group coordinated by materials engineer Luiz Henrique Capparelli Mattoso. But the transfer made to a company called BR Sensor restricts the application to coffee. Heading up the company is materials engineer Gustavo Figueira de Paula, who took part in the project in the course of his work for a master’s degree at the Federal University of São Carlos (UFSCar).

Abic is also a partner in the development of the electronic tongue. “For at least two years, the association has been supplying samples and assisting in steering the work to meet the needs of the industry”, Figueira de Paula says. The equipment still needs some adjustments, such as being more compact, before being offered to the market. The Regional Cooperative of Coffee Growers in Guaxupé (Cooxupé), in the south of Minas Gerais, with about 9 thousand members, has already been in touch with Embrapa to get to know details of the product. In the harvest period, the cooperative, which exports over 1 million bags a year, tastes as many as 2,500 cups of coffee a day.

Accurate examination
The third technology licensed uses methodology tested and approved by Faber-Castell, a company that produces 1.5 billion pencils a year.  This is the portable tomograph, which employs the same principle as the equipment used in medicine in tomography examinations to evaluate the density of wood. This evaluation is necessary, because the wood from the pinus, used to manufacture pencils, is divided into different categories, according to the kind of product it is intended for. The selection of the matrices for cloning is made from measurements taken in the field. With tomography, the result is known on the spot. “The density distribution map in the areas of the tomographic cut at each point of the tree shows fissures or faults existing in the wood”, says researcher João de Mendonça Naime, the coordinator of the research.

By the traditional method, a piece of wood the size of a pencil has to be taken from the tree, which is taken to the laboratory and evaluated with X-ray equipment. Besides being a method that is invasive for the tree, the examination is impaired because only a small piece of the wood is analyzed. “Without this evaluation, it is often only after three years in the field that it is known for sure whether that one is the best matrix”, Naime says.

Termite attack
Besides evaluating the density of the wood in the field, the method serves to verify the conditions of urban trees, many of them impaired from termite attacks. For this application, it is necessary to use a source of radiation with more energy, because of the difference in the diameter of the tree planted for industrial purposes, which is thinner, compared with ornamental trees used in the cities. For the pinus, for example, the tomography is done with a source of cesium 137, a radioisotope that emits gamma radiation. But for trees of a larger diameter, there has to a radioactive source like cobalt 60. Pulp and paper companies have already shown interest in the innovation, for controlling the quality of the wood.

The fruit sector, particularly fruit for export, is amongst the potential customers for the photoreactor for treating pesticide residues in water, one of the technologies licensed. During the process of cleaning the fruit, the water used gets contaminated with residues of the agrochemical applied. The big problem that afflicts the packing houses, which take care of the selection and packaging of farm products, is how to treat this discarded water.

As the equipment currently available to do this treatment is expensive, the researchers from Embrapa, supervised by Martin Neto, the general head of Embrapa’s unit, and Débora Milori, a researcher in optics, began to look for a low cost alternative. To do so, they developed a piece of equipment, at the prototype stage, that uses a process of photodegradation to decompose the pesticide present in the water. The technique, known as photocatalysis, uses a source of ultraviolet light and a catalyst, in this case titanium dioxide, a semiconductor responsible for accelerating the chemical reaction that breaks down the pesticide molecules, removing them from the water.

“Our forecast is, in the next six months, to carry out an adaptation of the product, which is going to depend on the quantity of residue generated and on the volume of water, and, by the end of the year, to be on the market with it”, says José Roberto Garbin, from Natureza Ativa, the company that is going to take care of perfecting the technology. Garbin took part in the development of the equipment, carried out during his research for a doctorate at the Physics Institute of the University of São Paulo (USP), in partnership with Embrapa. The theme of the thesis was studying the mechanisms of reaction in the photodegradation of pesticides. Aside from the packing houses, other market niches that the company intends to serve are the rural producers, which have to wash every day their protective clothes and the equipment used in the application of pesticides, besides companies that carry out the recycling of the packaging used for these products.

Expensive transport
The recycling of residues coming from the treatment of residential sewage is also covered by the technology passed on to the company called Aliança Orgânica. The process of making use of the sludge from sewage began to be developed in 2003, under the coordination of researcher Wilson Tadeu Lopes da Silva, and it was able to count on the participation of a former researcher from Embrapa, Antonio Pereira de Novaes. The idea arose from a demand from the construction company Sobloco, responsible for a condominium at Riviera de São Lourenço, in Bertioga, on the coast of São Paulo. After the sewage from the condominium is treated by a physical-chemical process, in which the solid is separated from the liquid, the water becomes crystal-clear, but sludge is left over. This material had to be transported in trucks to the sanitary landfill of Mogi das Cruzes, a town some 60 kilometers away, which made the treatment process more expensive. “This sludge has organic matter and is a nutrient for plants that can be put to use in agriculture, if it is properly worked on”, says Lopes da Silva.

The process developed, which eliminates the pathogenic germs and stabilizes the organic matter for it to be incorporated into the soil as fertilizer, is made up of two stages. First, a mixture is made of the sludge with green tree prunings and grass clippings in suitable proportions, in furrows, in rectangular heaps. The bacteria naturally present in the medium go into action and begin to feed on the nutrients. Inside these heaps of organic matter, the temperature reaches 65°C on account of this microbial activity. “At that temperature, the pathogenic microorganisms, like the fecal coliforms, do not survive”, Lopes da Silva says.

In the second phase of the process, called the maturing stage, another bacterium is inoculated to improve the humus, a kind of organic fertilizer. The process has now been tested with success, but it will be up to Aliança Orgânica, whose partners work with basic sanitation and organic fertilizers, to transform the technology into a product, because the system has to be molded to each customer, mainly due to the analysis of the composition of the sludge in the different kinds of sewage. From the plans of the companies that have licensed the technologies, even with the adjustments needed at this current stage of transition, they should all be on the market in a year at the most. The contracts signed stipulate the payment to Embrapa of 5% in royalties on sales.

Winning ideas
The process of constructing artificial lakes for environmental purposes and making water available was the winner in the category Management of Water Resources category of the Banco do Brasil 2005 Social Technology Award. The proposal is to give awards to projects that ally popular wisdom, social organization and scientific knowledge. The lake project is based on covering the bottom of these environments with a plastic tarpaulin. It was developed by Embrapa Wheat and Sorghum, a unit of the Brazilian Agricultural Research Corporation installed in the town of Sete Lagoas, in Minas Gerais. Coordinated by agronomist engineer Luciano Cordoval de Barros, the lined lakes are now used by packing stations, pig farmers and communities that have community gardens. In the first two cases, the lakes are used for depositing and cleaning water with excrement, by means of treatment with aerobic and anaerobic bacteria that consume all the organic matter existing in the dirty liquid, before it is reused in other functions on the properties or poured into rivers or streams. In the case of the gardens or when used in put-and-take fisheries (fish and pay) and in fish farming, the tarpaulin, which has on top of it a 25 centimeter layer of earth, does not let the water penetrate into the ground and acts like a reservoir, when the catchment from rivers is not sufficient at certain times of the year. Besides the R$ 50 thousand from Banco do Brasil, the Multiple Use Lake for Environmental Protection project also received R$ 5 million from Petrobras, which was a partner in the organization of the award, to finance the dissemination of the technology in Brazil. The bank also enjoyed support from the United Nations Educational, Scientific and Cultural Organization (Unesco) and the PricewaterhouseCoopers audit firm. The award has three thematic categories, and one of them is water resources. The other two were Children’s and Adolescents’ Rights, the winner of which was the Ambulant School project, of the Santa Fé Beneficent Association, from São Paulo, and Education, with the Connections of Learning project, for the Shantytown Observatory of Rio de Janeiro.

The first is an educational and research support system about the origin and family conditions of children and adolescents who live on the streets of the cities. The proposal of the Ambulant School is to develop a school in a square which these children and adolescents attend, for them to be better known and understood, including as far as their family situation is concerned. This work has to be done following an ethnographic analysis (of anthropological and social characteristics) to be carried out in areas with 4 square kilometers in 40 days. The objective of the Connections of Learning project is to keep youngsters from poor homes at public universities, by means of a network made up of students, inhabitants in popular communities, teachers and postgraduates, which, besides providing a research and extension scholarship financed by the Ministry of Education for the pupil, instigates community participation and production of knowledge with scientific rigor about the communities and drawing them closer to the university.
The other categories are regional. The winners were, in the Center-West region, the Modern Campo Grande Teaching Association, of Campo Grande (MS), in the Northeast, the Association of Dwellers of the Palmeira Estate of Fortaleza (CE), in the North, the Ilha das Cinzas Agro-Extractivist Workers Association, in the municipality of Gurupá (PA), in the Southeast, the Ecological Researches Institute (Ipê), from the town of Teodoro Sampaio (SP), and in the South region, the Pequeno Cotolengo Paranaense, of Curitiba (PR). Other information about the award can be found in the website:

The projects
1. Characterization of polymeric sensors of interest to agroindustry (nº 00/11177-9); Modality Regular Line of Research Grants; Coordinator
Luiz Henrique Capparelli Mattoso — Embrapa; Investment R$ 32,470.12 and US$ 31,794.55 (FAPESP)
2. Development of methodologies using photothermal techniques – photoacoustic and photopyroelectric — for the determination of impurities added intentionally to food (nº 00/12373-6); Modality Regular Line of Research Grants; Coordinator Washington Luiz de Barros Melo — Embrapa; Investment R$ 19,913.36 and US$ 27,950.00 (FAPESP)