The increased demand for organic food, free from pesticides, herbicides and chemical additives, has grown significantly over the last few years, stimulated, in particular, by countries that import agricultural products from Brazil. But the great doubt that afflicts the end consumer, who pays up to four times more for this food, is to know if the product really does meet the concept of organic, in all the stages of the process. To give a guarantee of quality for these foods, substantiated in the form of a green seal – also demanded by the Ministry of Agriculture -, researchers from the Center for Nuclear Energy in Agriculture (Cena), of the University of São Paulo (USP) are developing advanced methods for routine analysis, capable of confirming whether a product really has been produced without any kind of chemical treatment, from the plantation to the point of sale.
More efficient and less expensive than the tests currently available, the analysis will make it possible for the current certification system, based only on an assessment of the process of production, to be perfected. With this, the hope is that the sector will gain more credibility, both in the domestic market and abroad, contributing towards the elimination of the current health barriers for exports.
All the certification work began with research coordinated by Professor Siu Mui Tsai, of Cena’s Molecular and Cellular Biology Laboratory, which started with a project financed by FAPESP, under the Partnership for Technological Innovation (PITE) program. A farm in the city of Batatais, in the Ribeirão Preto region, Shimura’s Alimentos, gave logistic support for the project, which has already resulted in the creation of certification standards of several products, such as coffee, sugar, soybeans, corn, potato and beans. It is a good start, as reference standards for the analysis had to be created, calling for controlled cultivation to guarantee the complete absence of chemical products.
To implement the new analyses and to carry out the certification of farm products in the future, Cena created the Food Safety Laboratory, which is expected to be ready in May. The new unit will be devoted to the certification of agricultural products, including organic food. It thereby hopes to meet the current demand for analyses, generated both by the improvement of the food safety policies and by occasional events, such as the appearance of the mad cow disease and the outbreaks of foot-and-mouth disease.
“As the market becomes more and more demanding, the producers must adapt to new rules, obeying standards that were not required before”, explains Elisabete De Nadai Fernandes, from Cena’s Radioisotope Laboratory. Grain exports, for example, are a concern, because they can be rejected in European countries, like Switzerland, should they contain a percentage higher than 0.1% of transgenic seeds. The inspection is no less strict for the hormones and antibiotics presence in export meat.
End of the uncertainties
At the moment, anyone buying products with the “organic food” seal is not totally free from being fooled. Although there is in Brazil a well structured certification system, with four agencies responsible for inspecting production in the field and for guaranteeing that the producers are following all the technical rules for cultivation and obeying the prohibition over the use of any chemical product, the consumer still has reason for doubts. “Who can guarantee that the fruit has not been sprayed with agro-chemicals for post-harvest conservation, or that the product has not been mixed with or even exchanged for another non-organic one?”, asks Tsai.
For the researcher, the failure of the current system lies in the method of certification, which is based only on an assessment of the production process, and not on the analysis of the end product. This happens because, so far, laboratory research was very expensive and not very sensitive. The most usual method for detecting microbial toxins, immunochemical assay, is not recommended for routine exams, because it would increase even more the cost of production, making the sector’s business unfeasible. The alternative is based on isotopic and nuclear techniques used to detect radioactivity in food, carried out at the Nuclear and Energy Research Institute (Ipen). Food is irradiated and become more susceptible to the analysis of the chemical elements that make them up. “This way, testing organic products is going to be far more accessible, besides being more efficient”, warrants Elisabete.
The technique was used to analyze coffee beans, in one of the research projects connected with Cena. Still at the finishing stage, the thesis for a doctorate by Fábio Sileno Tagliaferro made it possible to identify differences in the concentration of a few substances present in coffee, which are indicators of organic cultivation. Compared with conventional coffee, organic coffee shows lower concentrations of bromine, cobalt, cesium and rubidium, while the level of calcium is higher. The result confirms that the use of agrochemicals leaves traces, which can be detected as alterations in the chemical composition of the food. “They are very small differences, but easily detected, provided that one has a proper laboratory structure and qualified personnel”, explains the researcher.
Putting these analyses into practice on a large scale to attend to the producer may still take from one to two years. Before that, the composition of each product has to be known, that is, the creation of standards that allow comparisons between what are and what are not organic foodstuffs.
The partnership with Shimura’s led to paths not foreseen at the beginning of the project, but which helped to confirm the effectiveness of some procedures for clean production. Right in the beginning, the need arose for finding a solution to closing the productive cycle on the farm. The greatest difficulty was to eliminate the contamination from a pond with dung from pig raising. The solution found by the researcher was to take to the farm an army of earthworms, animals that are by their very nature transforming agents. Beds were then built for the wormery, where waste from the production of corn (grown for pig feed) and manure from the herds (of cattle and pigs) were deposited. In the experiment, the worms used were those that go under the names of African earthworm or African Night Crawlers (Eudrilus eugeniae), which originally from West Africa and measure from 20 de 22 centimeters.
The organic compost (decomposed feces) produced by the worm, identified as worm compost and popularly called humus, has a granulated form that favors the airing of the soil and improves the laying down of roots. In addition, the substances that it contains provide a greater quantity of nutrients that can be assimilated by plants – it is rich in nitrogen, phosphorus (which is what soils lack most), iron, zinc, manganese and mineral salts – and increase the retention of water. Tests with bean plants showed that the plants became more robust, with stronger roots. With humus, the nutrients are released gradually, in a longer action than traditional fertilizing, and may last up to two years.
With the PITE project, it was possible to format the process for making a product that is hardly conventional: worm flour. In this process, the worms remain quarantined and undergo several washes before being sterilized. In a lyophilizer (a freeze dryer), they are frozen at 40 degrees below zero, and then heated up gradually to 40 degrees above zero, to eliminate all the water. Finally, they are ground and encapsulated. The nutritional properties of worm flour have been described in several studies abroad, above all, in the United States, China and Australia, where the product is recommended for feeding growing animals, like chicks, ornamental fish tadpoles, shrimps and birds.
There are indications that worm meal is also a powerful food supplement for humans. “We now know that it reduces cholesterol in the blood and has an anticoagulant action”, explains Tsai. But, according to Hélio Vanucci, a member of the Technical Chamber for Functional Food of the National Agency for Sanitary Surveillance (Anvisa), the release of the product for human consumption still depends on tests that prove its effectiveness and safety.
To encourage the activity of raising worms, the team involved in the project started a project to bring awareness to the farmers, with the distribution of a leaflet, in comics format, where the characters tell of the thousand and one uses of worms, in a humorous manner. In Superworm’s Adventures , the personages take a walk through nature, showing the role played by worms in maintaining the ecological balance, explain how a wormery is built, and show a worm meal factory.
Food Quality and Agriculture in a Market Economy: Organic Production and Certification of Farm Products for Obtaining the Approval of the Green Seal (nº 97/13244-0); Modality Partnership for Technological Innovation (PITE); Coordinator Siu Mui Tsai – Cena’s Molecular and Cellular Laboratory; Investment R$ 124,500.00 and US$ 56,111.11 (FAPESP) and R$ 74,200.00 (Shimura’s)