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Primary and secondary metabolites from green beans collected from vertical canopy layers related with the sensorial attributes of coffee beverage

Scholz M.B.D.S., Kitzberger C.S.G., Rakocevic M., Durand N.. 2015. In : Proceedings of the 25th International Conference on Coffee Science. Paris : ASIC, p. 42-45. International Conference on Coffee Science. 25, 2014-09-08/2014-09-13, Armenia (Colombie).

The isomers of chlorogenic acids (CQAI), and other chemical compounds in green coffee beans, contribute on formation of complex sensorial attributes of coffee beverage. The aims of this study were to estimate the chemical composition, including CQAI, in green coffee beans collected from canopy vertical layers of Coffea arabica L. (cv. IAPAR 59) and to associate this composition to the sensorial attributes of coffee beverage.The plants were grown in two densities (6,000 and 10,000 plants ha-1), and twoplanting patterns (PP),square (Q) and rectangular (R), resulting in four combinations (Q6, Q10, R6 and R10).Two 40cm-thick layers in vertical profile of coffee canopy were considered (upper layer - Luand inferior layer - Li).The concentration of fats, proteins, sucrose, reducing sugars, phenolic compounds (PC), chlorogenic acids and caffeine in green coffee beans were performed by NIRS. The mass/volume ratio was considered as the green beans density. The following isomers: 3-caffeolquinic acid (3-CQA), 4-caffeolquinic acid(4-CQA), 5-caffeolquinic acid(5-CQA), 5-feruloylquinic acid (5-FQA), 3,5-dicaffeoylquinic acid (3,5-diCQA), 4,5-dicaffeoylquinic (4,5-diCQA) and 3,4-dicaffeoylquinicacid (3,4-diCQA) were determined by ultra fast liquid chromatography. Principal component analysis (PCA) was applied to associate the coffee beans physicochemical components to the plant density, planting patternsand canopy layers. The PCA was efficient to discriminate between two PPs, showing that beans originated from rectangular ones contented chemical composition that was associated to better beverage quality. The free-choice profile technique (FCP) was employed to estimate the sensorial attributes of coffee beverage. FCPindicated that the beverage from Liexpressedsweetness, bitterness, browncolorandlow astringency. In PCA those samples were related to high concentrations of 3,4-diCQA, sucrose, caffeine and proteins.The PCA and FCP analysis showed the influence of berry position on plant architecture. The berries maturated in the self-shaded layer (Li) had the chemical composition that resulted in more appropriated beverage attributes than those ones formed and maturated in sun-exposed (Lu) layer. In the second production year, the rectangular PPs originated berries with better chemical and sensory attributes.

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