Recebido para publicação em 15/05/2014 e aprovado em 11/10/2014. 1 Engenheira-Agrônoma, Doutora. Departamento de Fitotecnia, Universidade Federal de Viçosa, Campus Viçosa, Avenida Peter Henry Rolfs, s/n, 36570-000, Viçosa, Minas Gerais, Brasil. herminia@ufv.br (autora para correspondência Nutrição mineral do cafeeiro e qualidade da bebidaOs nutrientes minerais interferem na qualidade final do café por duas vias, uma direta, por seu papel no metabolismo da planta e acúmulo de compostos químicos desejáveis, do ponto de vista do aroma e sabor do café, e, outra, indireta, por seu papel na produção de compostos que desfavorecem o desenvolvimento microbiano nos grãos. Neste trabalho, procurou-se destacar as características químicas dos grãos associadas à qualidade da bebida e suas possíveis interações com os macro e micronutrientes, bem como relatar os resultados de pesquisa que relacionam nutrição mineral, qualidade da bebida e produção de compostos a ela associados. Palavras-chave: Coffee mineral nutrition and beverage qualityMineral nutrients influence the final quality of coffee in two ways: first directly, for their functions in plant metabolism and accumulation of desirable chemical compounds from the standpoint of flavor and taste of coffee; and indirectly, for its role in producing compounds that are harmful to microbial growth in beans. In this study, we focused on the chemical compounds of green coffee related to good beverage quality and its possible interactions with macro and micronutrients. We also report research findings that relate mineral nutrition, beverage quality and production of compounds in coffee beans.

ResumoO trabalho teve como objetivo avaliar a produtividade e a qualidade de frutos de mamoeiro 'Sunrise Solo' em função de doses de nitrogênio e boro. O trabalho foi desenvolvido na fazenda Chan de Jardim no Centro de Ciências Agrárias-UFPB no Município de Areia, em um solo de textura arenoargilosa classificado como Neossolo Regolítico. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições e duas plantas úteis por parcela com bordadura simples. Para a composição dos tratamentos, utilizou-se a matriz experimental Plan Puebla III, onde se definiram as doses para nitrogênio (0,0 -111,2 -200 -288,9 -400 g planta -1 , e para boro (0,0 -0,83 -1,5 -2,16 -3,0 g planta -1 ), totalizando dez tratamentos. A adição de nitrogênio aumentou a produtividade, o peso médio dos frutos e o número de frutos por planta. As doses de nitrogênio e boro aumentaram o diâmetro e comprimento do fruto, rendimento de semente e teor de sólidos solúveis totais. O pH da polpa decresceu linearmente com o aumento das doses de N e de boro. Houve efeito significativo das doses de N sobre o teor de vitamina C. Palavras-chave: Rendimento, mamão, qualidade, nutrição AbstractThe study aimed to evaluate the yield and fruit quality of papaya 'Sunrise Solo' as function of nitrogen and boron fertilization. The experiment had a randomized block design with four replications, two plants per plot with a single border. To make up the treatments, we used the experimental array Plan Puebla III, which set the rates for nitrogen (0.0 to 111.2 -200 -288.9 -400 g plant -1 , and B (0.0 -0.83 -1.5 -2.16 -3.0 g plant -1 ), in a total of ten treatments. The addition of nitrogen increased the yield, average fruit weight and number of fruits per plant. The nitrogen and boron increased the diameter and length of the fruit, amount of seeds and content of soluble solids. The pH of the pulp decreased linearly with increasing doses of nitrogen and boron. It was observed a significant effect of N rates on the level of vitamin C.

Zinc is essential for the synthesis of amino acids, carbohydrates, and proteins, which are directly related to the chemical composition of raw coffee (Coffea arabica L.) beans, and it may influence the quality of the beverage. This study aimed at evaluating the influence of Zn doses on the chemical composition of coffee beans and beverage quality. Increased Zn availability in the growth medium maximized attributes related to beverage quality, such as polyphenol oxidase activity, color index, and contents of sucrose, caffeine, and trigonelline, reaching maximum values in plants with Zn leaf contents within the sufficiency range of 8.0 to 12.7 mg kg−1. Zinc doses lower or higher than the one that provided maximum quality (∼2 μmol L−1 in nutrient solution) increased the attributes related to loss of beverage quality, such as content of total phenols, 5‐caffeoylquinic acid, leached K, and electrical conductivity. Zinc supply influences the quality of coffee beans, having a positive effect on polyphenol oxidase activity, color index, and contents of sucrose, caffeine, and trigonelline. Adequate Zn doses reduce total phenol content, 5‐caffeoylquinic acid, leached K, and electrical conductivity. The leaf contents, which related to the minimum or maximum points of the quality attributes studied, varied between 8.0 and 12.7 mg Zn kg−1.

The objective of this work was to evaluate the effect of copper on the chemical composition of coffee beans and on the quality of the beverage, relating both of them to the Cu leaf contents in coffee (Coffea arabica) plants. Coffee plants were grown in a hydroponic system containing 0.2, 0.4, 0.8, 1.6, and 3.2 μmol L-1 Cu until fruit setting. Coffee bean production was evaluated, and, after the cherries were dried, the following characteristics were determined: leaf Cu content; total titratable acidity; color index; electrical conductivity; leached K; polyphenol oxidase (PPO) activity; concentrations of caffeine, trigonelline, organic acids, total phenols, chlorogenic acids (3-CQA, 4-CQA, and 5-CQA), sucrose, glucose, arabinose, mannose, and galactose; and sensory quality of roasted beans. Cu increased bean yield, PPO activity, and the concentrations of organic acids, 3-CQA, sucrose, and arabinose. Total titratable acidity, total phenols, 4-CQA, and 5-CQA were reduced with increasing Cu doses. Leaf contents related to the maximum and minimum values of desirable and undesirable quality attributes ranged from 5.6 to 11.4 mg kg-1 Cu, respectively. Copper affects the production and chemical composition of coffee beans, and the attributes related to quality are maximized in plants with low leaf contents of the nutrient.

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