Química Nova

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/13323

Navegar

Filtros

2011 - 20122

Configurações

Autor: search.filters.author.Arruda, Neusa P.Data final: 2019

Resultados da Pesquisa

Agora exibindo 1 - 2 de 2
  • Imagem de Miniatura
    Item
    Correlação entre precursores e voláteis em café arábica brasileiro processado pelas vias seca, semiúmida e úmida e discriminação através da análise por componentes principais
    (Sociedade Brasileira de Química, 2012) Arruda, Neusa P.; Hovell, Ana M. C.; Rezende, Claudia M.; Freitas, Suely P.; Couri, Sonia; Bizzo, Humberto R.
    The influence of pre processing of arabica coffee beans on the composition of volatile precursors including sugars, chlorogenic acids, phenolics, proteins, aminoacids, trigonelline and fatty acids was assessed and correlated with volatiles formed during roasting. Reducing sugars and free aminoacids were highest for natural coffees whereas total sugars, chlorogenic acids and trigonelline were highest for washed coffees. The highest correlation was observed for total phenolics and volatile phenolics (R= 0.999). Experimental data were evaluated by Principal Components Analysis and results showed that washed coffees formed a distinct group in relation to semi-washed and natural coffees.
  • Imagem de Miniatura
    Item
    Discriminação entre estádios de maturação e tipos de processamento de pós-colheita de cafés arábica por microextração em fase sólida e análise de componentes principais
    (Sociedade Brasileira de Química, 2011) Arruda, Neusa P.; Hovell, Ana M. C.; Rezende, Claudia M.; Freitas, Suely P.; Couri, Sonia; Bizzo, Humberto R.
    A fruit chemical composition reflects its maturation stage. For coffee, it is also the reflex of the post harvesting processing type, dry, semi-wet and wet. The object of this work was to verify if headspace solid phase microextraction coupled to gas chromatography (HS-SPME-GC) could be used to discriminate between samples harvested in different maturation stages and treated by different processes. With application of principal component analysis to the area of 117 compounds extracted by SPME, using divinylbenzene/Carboxen/polydimethylsiloxane fiber, it was possible to discriminate, in the roasted and ground coffee, the maturity stage and processing type used.