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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

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Resultados da Pesquisa

Agora exibindo 1 - 3 de 3
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    Post-harvest processing of coffee: an overview
    (Editora UFLA, 2021) Das, Suryatapa
    Coffee is known as one of the most popular beverages around the world. Coffee belongs to the botanical family Rubiaceae and genus coffea. The two most economically important species are C. arabica (arabica coffee) and C. canephora (robusta coffee).The health benefits of coffee are due to presence of many biologically active components such as caffeine, chlorogenic acid, nicotinic acid, quinolinic acid, trigonelline, tannic acid, and pyrogolic acid. The postharvest processing of coffee cherry involves dry or wet processing, grading, sorting, marketing, blending, and roasting. A series of physical and chemical changes occur during coffee roasting that are responsible for the development of pleasant aroma and flavour of coffee.
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    Discrimination of commercial roasted and ground coffees according to chemical composition
    (Sociedade Brasileira de Química, 2012) Souza, Romilaine M. N. de; Benassi, Marta T.
    Roasted and ground 38 commercial coffees and coffees of known species (arabica, robusta) were characterized by principal component analysis using as variables nicotinic acid, trigonelline, 5-o-caffeoylquinic acid (5-CQA), caffeine, kahweol and cafestol, which are potentially indicative of species. The objective of the study was to assess the relevance of such parameters in coffee discrimination. Nicotinic acid allowed the characterization of roasting degree. Trigonelline and 5-CQA presented variability among arabica and robusta coffees as well as among comercial ones. Thermostable parameters (caffeine, kahweol and cafestol) had high discriminative potential between the species. In general, high levels of caffeine and low levels of diterpenes (kahweol and cafestol) were related with higher proportions of robusta in the products, which were observed by the decreasing kahweol/cafestol ratio and increasing caffeine/kahweol ratio. The use of these new parameters (kahweol/cafestol and caffeine/kahweol ratios) was suggested as tools for assessing the addition of robusta in commercial coffees.
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    Statistical procedure for the composition of a sensory panel of blends of coffee with different qualities using the distribution of the extremes of the highest scores
    (Editora da Universidade Estadual de Maringá - EDUEM, 2019) Cirillo, Marcelo Ângelo; Ramos, Mariana Figueira; Borém, Flávio Meira; Miranda, Felipe Mesquita de; Ribeiro, Diego Egídio; Menezes, Fortunato Silva de
    The identification and interpretation of discrepant observations in sensory experiments are difficult to implement since the external effects are associated with the individual consumer. This fact becomes more relevant in experiments that involve blends, which scrutinize coffees with different qualities, varieties, origins, and forms of processing and preparation. This work proposes a statistical procedure that facilitates the identification of outliers while also evaluating the discriminatory powers of a sensory panel concerning the differentiation of pure blends and coffees. For this purpose, four experiments were performed that tested coffees with different qualities and varieties. The results suggest that the statistical procedure proposed in this work was effective for discriminating the blends relative to the pure coffees and that the effects of the concentrations and types of processing did not interfere with the statistical evaluations.