Analytical investigation of Rio off-flavor in green coffee

Spadone, J. C.; Takeoka, Gary R.; Liardon, R.

doi:10.1021/jf00091a050

Cited by 109 publications

(78 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…O 2-metóxi-fenol (guaiacol) e seus derivados também foram descritos por vários autores 4,[9][10][11][12][13]17,18 . Os fenóis encontrados em maior quantidade no café torrado são: o 4-vinil-guaiacol (8-20 mg/ Kg de café torrado), o guaiacol (2-3 mg/Kg) e o fenol (1,2-2,2 mg/Kg) 19 .…”

Section: Fenóisunclassified

Componentes voláteis do café torrado. Parte II. Compostos alifáticos, alicíclicos e aromáticos

Moreira¹,

Trugo²,

María³

2000

Quím. Nova

View full text Add to dashboard Cite

This review is about the aliphatic, alicyclic and aromatic compounds (non-heterocyclic compounds) that are present in the volatile fractions of roasted coffees. Herein, the contents, aroma precursors and the sensorial properties of volatile phenols, aldehydes, ketones, alcohols, ethers, hydrocarbons, carboxylic acids, anhydrides, esters, lactones, amines and sulphur compounds are discussed. Special attention is given to the compounds of these groups that are actually important to the final aroma of roasted coffees.Keywords: non-heterocyclic compounds; aroma; roasted coffees. REVISÃO INTRODUÇÃOA bebida produzida a partir do café é considerada uma das mais populares do planeta. Em 1991, o consumo dessa bebida nos Estados Unidos foi de aproximadamente 106 litros por pessoa 1 . No comércio internacional, os grãos de café não-torrados perdem em importância apenas para o petróleo. Essa matéria-prima costuma ser cultivada em regiões de clima tropical e subtropical e, normalmente, representa um item importante da pauta de exportação dessas regiões (ex. Brasil). Uma característica interessante da bebida do café é o fato de não possuir valor nutricional relevante, sendo consumida basicamente devido aos efeitos fisiológicos e psicológicos relacionados à presença da cafeína e, principalmente, pelo prazer e satisfação que seu aroma e sabor são capazes de proporcionar 2 . Dos dois atributos sensoriais mencionados acima, o aroma é indubitavelmente o mais complexo. Enquanto a sensação do sabor é relativamente simples, sendo normalmente classificada em quatro qualidades (doce, salgado, amargo e azedo), as modalidades de aroma ainda estão sendo intensamente discutidas nos meios científicos. No final da década de 60, por exemplo, foram caracterizados 44 tipos básicos de odor 3 . O aroma do café é formado por uma mistura extremamente complexa de inúmeros compostos voláteis que apresentam qualidades de aroma, intensidades e concentrações diferentes. Dessa maneira, a contribuição de cada um desses compostos voláteis para o aroma final do café é bem variada, podendo ainda ocorrer interações sinergísticas e antagônicas entre esses diferentes compostos. Esses compostos voláteis são gerados basicamente durante a torrefação do café verde. O café processado contém mais compostos voláteis do que qualquer outro alimento ou bebida (aproximadamente mil compostos voláteis já foram identificados nesse produto) 4 . Dentre esses compostos voláteis, o grupo dos heterocíclicos vem sendo bastante estudado. Nesse grupo, foram identificados vários compostos que aparentam ser de impacto para o aroma final do café torrado (ex. 2-furilmetanotiol, caveofurano, N-furil-2-metil-pirrol) 5,6,7 . Além dos heterocíclicos, existem vários outros compostos na fração volátil do café que merecem semelhante atenção por parte dos pesquisadores da área. Esses compostos, aqui classificados como alifáticos, alicíclicos e aromáticos, normalmente são encontrados em baixas concentrações, o que dificulta seu estudo quantitativo e a avaliação de suas propriedades sensoriais. D...

show abstract

Section: Fenóisunclassified

Componentes voláteis do café torrado. Parte II. Compostos alifáticos, alicíclicos e aromáticos

Moreira¹,

Trugo²,

María³

2000

Quím. Nova

View full text Add to dashboard Cite

show abstract

“…There are many studies on the off-flavor of coffee (Blank and Grosh, 2002;Cantergiani et al, 2001;Czerny et al, 2000;Lindinger et al, 2009;Spadone and Takeoka, 1990). The most non-preferable flavor among them is Rio flavor, which consists of medicinal, phenolic, iodine-like and chlorine-like flavors found in tap water in Japan.…”

Section: Introductionmentioning

confidence: 99%

“…The most non-preferable flavor among them is Rio flavor, which consists of medicinal, phenolic, iodine-like and chlorine-like flavors found in tap water in Japan. Causal substances of Rio flavor hitherto detected and discussed are 2,4,6-trichloroanisole (TCA) and its precursors, 2,4,6-trichlorophenol (TCP) and 2-methylisoborneol (MIB) (Spadone and Liardon, 1988;Spadone and Takeoka, 1990). 2,4,6-TCP has a high threshold and does not cause an off-flavor unless it exists in large amounts, but 2,4,6-TCA causes an off-flavor even at a low concentration.…”

Section: Introductionmentioning

confidence: 99%

“…2,4,6-TCP has a high threshold and does not cause an off-flavor unless it exists in large amounts, but 2,4,6-TCA causes an off-flavor even at a low concentration. Spadons et al analyzed Rio coffee from different areas such as Brazil and Puerto Rico, and identified 2,4,6-TCA and 2,4,6-TCP as off-flavor compounds (Spadone and Takeoka, 1990). Even in non-Brazilian coffee, 2,4,6-TCA and musty flavor components such as geosmin have been detected (Cantergiani et al, 2001).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Analysis of Iodine-like (Chlorine) Flavor-causing Components in Brazilian Coffee with Rio Flavor

Kato

Sato

Takui

2011

FSTR

View full text Add to dashboard Cite

Green beans and roasted beans of coffee with Rio flavor were analyzed by gas chromatographyolfactometry to clarify the causal substances of Rio flavor in Brazilian coffee. In addition to 2,4,6-trichloroanisole (TCA) and 2,4,6-trichlorophenol (TCP), which are known as the main causal substances of Rio flavor, a new iodine-like flavor-causing compound, 2,6-dichlorophenol (DCP), was detected. The detected amounts of 2,6-DCP and 2,4,6-TCA were less than 0.1 and 0.1 ppb in Rio flavor-free coffee beans, 0.8 and 1.2 ppb in weak Rio flavored beans, and 3.0 and 2.6 ppb in strong Rio flavored beans, respectively. Musty and chlorine flavors were sensed more strongly in model coffee containing both 2,4,6-TCA and 2,6-DCP than in the coffee containing them individually. In the present study, 2,6-DCP was identified as a new causal substance of Rio flavor, and it was found that the presence of 2,4,6-TCA intensifies Rio flavor, as a synergy effect.

show abstract

“…In fact, 2,4,6-TCA has been reported to be responsible for at least 80% of the cases of cork taint (8), and in a recent study Pollnitz and colleagues reported that 2,4,6-TCA could be detected in 100% of tainted wines (23). The role of chloroanisoles as contaminant agents is not restricted to wine, since the presence of these compounds is well documented in other food materials, such as eggs and poultry (12), chickens (11), pulp chips (10), dried fruits (30), Brazilian coffee (29), and drinking water (21).…”

mentioning

confidence: 99%

Characterization of an Inducible Chlorophenol O -Methyltransferase from Trichoderma longibrachiatum Involved in the Formation of Chloroanisoles and Determination of Its Role in Cork Taint of Wines

Coque

Álvarez-Rodríguez

Larriba

2003

Appl Environ Microbiol

View full text Add to dashboard Cite

A novel S-adenosyl-L-methionine (SAM)-dependent methyltransferase catalyzing the O methylation of several chlorophenols and other halogenated phenols was purified 220-fold to apparent homogeneity from mycelia of Trichoderma longibrachiatum CECT 20431. The enzyme could be identified in partially purified protein preparations by direct photolabeling with [methyl-3 H]SAM, and this reaction was prevented by previous incubation with S-adenosylhomocysteine. Gel filtration indicated that the M r was 112,000, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the enzyme was composed of two subunits with molecular weights of approximately 52,500. The enzyme had a pH optimum between 8.2 and 8.5 and an optimum temperature of 28°C, with a pI of 4.9. The K m values for 2,4,6-trichlorophenol and SAM were 135.9 ؎ 12.8 and 284.1 ؎ 35.1 M, respectively. S-Adenosylhomocysteine acted as a competitive inhibitor, with a K i of 378.9 ؎ 45.4 M. The methyltransferase was also strongly inhibited by low concentrations of several metal ions, such as Cu 2؉ , Hg 2؉ , Zn 2؉ , and Ag ؉ , and to a lesser extent by p-chloromercuribenzoic acid, but it was not significantly affected by several thiols or other thiol reagents. The methyltransferase was specifically induced by several chlorophenols, especially if they contained three or more chlorine atoms in their structures. Substrate specificity studies showed that the activity was also specific for halogenated phenols containing fluoro, chloro, or bromo substituents, whereas other hydroxylated compounds, such as hydroxylated benzoic acids, hydroxybenzaldehydes, phenol, 2-metoxyphenol, and dihydroxybenzene, were not methylated.

show abstract

Analytical investigation of Rio off-flavor in green coffee

Cited by 109 publications

References 15 publications

Componentes voláteis do café torrado. Parte II. Compostos alifáticos, alicíclicos e aromáticos

Componentes voláteis do café torrado. Parte II. Compostos alifáticos, alicíclicos e aromáticos

Analysis of Iodine-like (Chlorine) Flavor-causing Components in Brazilian Coffee with Rio Flavor

Characterization of an Inducible Chlorophenol O -Methyltransferase from Trichoderma longibrachiatum Involved in the Formation of Chloroanisoles and Determination of Its Role in Cork Taint of Wines

Contact Info

Product

Resources

About