Scientia Agrícola
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12094
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Item Agronomic practices toward coffee sustainability. A review(Escola Superior de Agricultura "Luiz de Queiroz", 2023-10-23) Martinez, Herminia Emilia Prieto; Andrade, Sara Adrián López de; Santos, Ricardo Henrique Silva; Baptistella, João Leonardo Corte; Mazzafera, PauloThe coffee sector is estimated to have a retail market value in excess of USD 83 billion, and over 125 million jobs have been created in the global coffee chain. The coffee specialty market has recently increased significantly, generating opportunities to certify coffee beans produced by sustainable practices. This avoids practices potentially harmful to the environment. Agroforestry, organic farming, intercropping, and soil conservation strategies are examples of sustainable alternatives in the production of coffee. In this review, we focus on practices for the sustainable management of coffee plantations that can help farmers fight problems caused by global warming. More specifically, we address soil organic matter and microbiota, the use of Urochloa grass as intercrop in coffee plantations, shading systems (including agroforestry), and organic coffee production. We concluded that from the agronomic viewpoint, we already have production techniques that can replace traditional ones with significant advantages accruing to the quality of coffee orchard ecosystems. Nevertheless, we need scientific research efforts to deal with the existing gaps and the engagement of the whole coffee chain as a means of guaranteeing an adequate profit to those smallholders who adopt and maintain sustainable practice and are capable of bringing several positive changes to the coffee crop, including the use of microbia-based commercial products and new organic sources of nutrients to complement chemical fertilizers and improve coffee quality.Item Simple procedure for nutrient analysis of coffee plant with energy dispersive X-ray fluorescence spectrometry (EDXRF)(Escola Superior de Agricultura "Luiz de Queiroz", 2013-07) Tezotto, Tiago; Favarin, José Laércio; Paula Neto, Ana; Gratão, Priscila Lupino; Azevedo, Ricardo Antunes; Mazzafera, PauloNutrient analysis is used to estimate nutrient content of crop plants to manage fertilizer application for sustained crop production. Direct solid analysis of agricultural and envi- ronmental samples by energy dispersive X-ray fluorescence spectrometry (EDXRF) was chosen as alternative technique to evaluate the simultaneous multielemental quantification of the most important essential elements in coffee (Coffea arabica L.) plants. Inductively coupled plasma atomic emission spectrometry and certified reference materials made from leaves were used to calibrate and check the trueness of EDXRF method for the determination of the concentration of several nutrients in coffee leaves and branches. Fluorescence spectrometry proved to be ad- vantageous and presented low cost as loose powder samples could be used. Samples collected from a field experiment where coffee plants were treated with excess of Ni and Zn were used to verify the practical application of the method. Good relationships were achieved between certi- fied values and data obtained by EDXRF, with recoveries ranging from 82 to 117 %.Item Extração e dosagem da atividade da polifenoloxidase do café(Escola Superior de Agricultura "Luiz de Queiroz", 2002-10) Mazzafera, Paulo; Gonçalves, Kátia Viviane; Shimizu, Milton MassaoA atividade de polifenoloxidase (PFO) tem sido usada como indicadora da qualidade de bebida de café. Foram feitas comparações entre o método tradicionalmente usado para extração de polifenoloxidase de café e outro, onde impediu-se a oxidação de fenóis durante a extração, com posterior eliminação por filtração em coluna de exclusão. Um método intermediário entre os dois também foi testado. As medições de atividade foram feitas por espectrofotometria e por consumo de O 2 . Os métodos tradicionais de extração e dosagem da atividade de PFO sofrem forte interferência de fenóis presentes no extrato, não permitindo reprodução dos dados publicados na literatura. Por espectrofotometria foi possível diferenciação apenas entre café de bebida Mole de cafés de bebida Dura e Rio, mas não entre as duas últimas. Café de melhor qualidade, bebida Mole, apresentou maior atividade de PFO. Extração de PFO na presença de antioxidantes e complexadores de fenóis, seguida pela eliminação dos mesmos por cromatografia de exclusão é essencial para uma avaliação correta. Entretanto, usando este procedimento e consumo de O 2 , a atividade de PFO também não diferenciou os três cafés testados, exceto o Mole dos dois outros. No lugar de DOPA (3,4 – dihidroxifenilalanina), usado comumente nas dosagens por espectrofotometria, sugere-se o emprego de ácido clorogênico (ácido 5-cafeoilquínico).Item Degradation of caffeine by microorganisms and potential use of decaffeinated coffee husk and pulp in animal feeding(Escola Superior de Agricultura "Luiz de Queiroz", 2002-10) Mazzafera, PauloCoffee husk and coffee pulp are coffee processing by-products. Coffee husk is obtained when harvested coffee is processed by the dry method, and coffee pulp is produced by the wet method. In Brazil, coffee is usually processed by the dry method, therefore an expressive amount of husk is obtained every year. Some of the husk is used as organic fertilizer but, other applications are very limited, mainly because it is a bulky product. The presence of tannins and caffeine diminish acceptability and palatability of husk by animals. This review discuss degradation of caffeine by microorganisms, with special attention to bacterial, biological decaffeination of coffee husk and pulp and its subsequent use on animal feeding. The known biochemical routes of caffeine degradation by microorganisms are initially discussed; problems concerning physiological effects in animals, focusing on the limitations imposed by caffeine as an antiphysiological component are raised; the use of microorganisms to decaffeinate coffee husk and pulp is discussed. The discussions offer a view on decreasing caffeine content of coffee husk and pulp, which would allow the use of larger amounts of these products in animal feeding, partially replacing traditional components such as cereal grains.