Coffee carbohydrates

Abstract

This review summarises recent advances in the chemistry, physiology and molecular properties of coffee carbohydrates with a particular focus on the cell wall polysaccharides. The results of detailed chemical studies have demonstrated novel structural features of both the galactomannans and the arabinogalactan polysaccharides of the green and roasted coffee bean. For the first time immunological probes based on monoclonal antibodies for specific polysaccharide epitopes were used to reveal the patterns of distribution of the galactomannans, arabinogalactans and pectic polysaccharides in the coffee bean cell wall. Finally, the results of physiological and molecular studies are presented which emphasise the growing awareness of the potential role the metabolic status of the green bean may play in final coffee beverage quality. Key words: Coffea, cell wall, beverage quality, seed. Carboidratos do café:Este artigo sumariza os mais recentes desenvolvimentos nas áreas de química, fisiologia e propriedades moleculares dos carboidratos do café, com um particular interesse nos polisacarídeos presentes nas paredes celulares. Os resultados dos estudos químicos detalhados demonstraram novas características estruturais tanto nos galactomananos como nos polissacarídeos dos arabinogalactanos do grão de café verde ou torrado. Pela primeira vez, estudos imunológicos baseados em anticorpos monoclonais foram usados para revelar a distribuição dos galactomananos, dos arabinogalactanos e dos polissacarídeos pectídicos na parede celular do grão de café. Finalmente, os resultados dos estudos fisiológicos e moleculares são apresentados de maneira a sublinhar a influência do status metabólico do grão verde do café na qualidade final da bebida. Palavras-chave: Coffea, parede celular, qualidade da bebida, semente.

Mutu Fisik Biji dan Citarasa Kopi Arabika Hasil Fermentasi Mikrob Probiotik Asal Pencernaan Luwak

“…Proses tersebut tidak sekedar degradasi lapisan lendir yang tersisa di permukaan kulit tanduk, tetapi juga terjadi peristiwa kimiawi yang sangat berguna dalam pembentukan karakter citarasa, yaitu pembentukan senyawa prekursor citarasa, seperti asam organik, asam amino, dan gula reduksi (Avallone, Brillouet, Guyot, Olguin & Guiraud, 2002;Jackels & Jackels, 2005;Redgwell & Fischer, 2006;Lin, 2010). Oleh karena itu, proses fermentasi merupakan tahapan yang penting dalam pengolahan kopi secara basah, mengingat pengaruhnya yang positif bagi peningkatan citarasa (FAO, 2004;Mondello et al, 2005;Singh & Singh, 2013;Correa et al, 2014).…”

“…Saat proses fermentasi terjadi peristiwa kimiawi yang sangat berguna dalam pembentukan karakter citarasa kopi, yaitu pembentukan senyawa prekursor citarasa seperti asam organik, asam amino, dan gula reduksi (Jackels & Jackels, 2005;Redgwell & Fischer, 2006;Lin, 2010). Buah kopi yang dimakan hewan luwak mengalami proses fermentasi dalam sistem pencernaannya selama ± 12 jam, kemudian dikeluarkan bersama feses pada proses ekskresi (Marcone, 2004a;Hadipernata & Nugraha, 2012).…”

Pengaruh Elevasi dan Pengolahan terhadap Kandungan Kimia dan Citarasa Kopi Robusta Lampung

“…Fermentasi merupakan peristiwa kimiawi yang sangat berguna dalam pembentukan prekursor citarasa biji kopi, yaitu asam organik, asam amino, dan gula reduksi (Avallone, Brillouet, Guyot, Olguin & Guiraud, 2002;Bytof, Knopp, Schieberle, Teutsch & Selmar, 2005;Jackels & Jackels, 2005;Redgwell & Fischer, 2006;Lin, 2010). Kandungan senyawa prekursor citarasa yang lebih banyak menghasilkan kualitas hasil penyangraian maupun seduhan kopi lebih tinggi dan mengandung senyawa citarasa lebih banyak sehingga mempunyai citarasa serta aroma lebih baik (Assis et al, 2005;Galilea, Fournier, Cid & Guichard, 2006;Bytof et al, 2007;Arruda et al, 2011).…”

Reducing the acidity of Arabica coffee beans by ohmic fermentation technology

“…The coffee flavor has influenced the way of processing, especially the process of fermentation and roasting (Avallone et al, 2002;Jackels and Jackels 2005;Pimenta et al, 2009;Budryn et al, 2011;Wang, 2012). Fermentation is a chemical event that is useful in forming the precursor flavor of the coffee beans in the form of organic acids, amino acids and reducing sugars (Avallone et al, 2002;Bytof et al, 2005;Jackels and Jackels., 2005;Redgwel and Fischer, 2006;Chang Lin, 2010). Differences in the coffee processing will produce different flavors, mainly due to different chemical composition (Farah et al, 2006;Bytof et, al., 2005;Taba, 2012).…”