PS268 Lecture Notes - Lecture 4: Dichloromethane, Health Canada, Coffea
Document Summary
Caffeine is a mild stimulant, methylxanthine biochemical family. Coffee, tea, and chocolate naturally contain xanthines (caffeine, theophylline, and theobromide, in right order) Unlike other alkaloids these are soluble in water. Caffeine has greatest stimulus effect, theobromine has almost none. Theophyline is most potent a caffeine least potent effect on cardiovascular system. Peak blood levels are reached 30 minutes after consuming caffeine and maximal cns effects are reached at two hours. Caffeine blocks the adenosine receptors, when it reaches the brain it releases norepinephrine and dopamine. Caffeinism a condition caused by an excessive intake of caffeine characteristics include insomnia, restlessness, excitement, fast hear rate, tremors and increased urination. Coffea arabica: milder flavour, take longer to develop after planting, near-tropical climate = more expensive and more desirable for most purposes. Coffea robusta: stronger, more bitter flavour, higher caffeine content, used in less expensive coffee and instant blends. Grown in colombia (arabica only) brazil (1), vietnam(2)
