Análise de trilha dos principais constituintes orgânicos e inorgânicos sobre a cor do caldo em cultivares de cana-de- açúcar

• Autor(a) principal: Santos, Fernando Almeida
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/4497
• topic: Cana-de- açúcar; Melhoramento genético; Modelos estatísticos; Sugarcane; Plant breeding; Statistical models; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA

Brazil is the main producer and exporter of sugar in the world. For 2008, its production is estimated to reach more than thirty million tons. One requirement for exportation of the sugar is its coloration, that must be in accordance with the International Commission for Uniform Methods in Sugar Analysis - ICUMSA. The color ICUMSA (sugar) can also be applied to the juice of the sugarcane. As less intense is the color of the juice, the clearest will be the sugar. As this color becomes more intensive, the sugar acquires darker coloration, becoming inadequate to exportation. This study was carried out to determine the effect of both organic and inorganic compounds on the color of the juice in cultivars of sugarcane. The trial was conducted in the experimental area pertaining to the Department of Plant Sciences, Universidade Federal de Viçosa, Viçosa-MG. The evaluations were accomplished in ratoon, on April and October 2007. The randomized experimental design was used, as being eight cultivars (RB72454, RB867515, RB835486, RB855156, SP80-1816, SP79-1011, RB855536 and RB92579) and five replicates. Ten plants in each plot were sampled for the accomplishment of the analyses. The juice was extracted by hydraulic press. The technological analyses (BRIX, POL, pH, PURITY, AR, ART and FIBER) were performed according to the method CONSECANA- SP. For analysis of the inorganic compounds (Cu, Al, Mg, Ca, K and P), the perchloric-nitric digestion was accomplished and the reading was performed in the spectrophotometer plasma. The extraction of the aconitic acid and phenolic compounds were accomplished with methanol/water (70:30) and hexane, as well as quantified by High Efficiency Liquid Chromatography - CLAE. For determination of the color by ICUMSA, the spectrophotometry method was used. The results showed the variables under study to differ in their degree of direct influence on the color of the juice. Copper and phenolic compounds were the characters providing the better explanation for the color of the sugarcane juice. However, the other characteristics must be taken into account due to high correlation, therefore suggesting the application of the selection index.