Wednesday, August 5, 2009
The Devils Brew aka Christian Crank
Many of you know that I was court mandated to stay away from coffee years ago. Luckily, I can still buy it for my friends and watch them drink it. I can drink as much Tea as a South African cricket team during a luncheon interval but coffee creates serious problems for this filter. Apparently, my reaction is not to caffeine but to some other constituent of coffee. So, all this month, we will delve deep into the molecular make up of coffee and it's Non-volatine chlorogenic acid content.
Chlorogenic acids belong to a group consisting of compounds which are known as polyphenols, which are antioxidants. The content of chlorogeneic acid in dried green coffee beans of robusta is 65 mg/ g and of arabica 140 mg / g, depending on the timing of harvesting. At roasting temperature, more than 70% of chlorogenic acids are destroyed, leaving a residue of less than 30 mg/g in the roasted coffee bean. In contrast to green coffee, green tea contains an average of 85 mg polyphenols/g. These chlorogenic acids could be a valuable inexpensive source of antioxydants. Chlorogenic acids are homologous compounds comprising caffeic acid, ferulic acid and 3,4 dimethoxycinnamic acid which are connected by an ester-bond to the hydroxy groups of quinic acid (1alpha, 3R, 4 alpha, 5R-tetrahydroxy-cyclohexane carboxylic acid). The anti-oxydation capacity of Chlorogenic acid is more potent than of ascorbic acid (vitamine-C) or mannitol, which is a selective hydroxy-radical scavenger. Chlorgenic acids have a bitter taste in low concentrations such as 50 mg / 1 L water. At higher concentrations of 1 g/ 1 L water they have a sour taste. Chlorogenic acid increase the solubility of caffeine and are important modulaters of taste. More later.