TEA AND CAFFEINE
Benefits of Caffeine
Caffeine does provide many benefits. Its well-known stimulatory effects on the central nervous system result in heightened awareness, focus, and coordination. It also reduces inflammation, helps with short-term memory and mood, and is a component of many medicines.
Caffeine in Tea
While there is less caffeine in brewed tea than in brewed coffee, we also experience that caffeine differently. The polyphenols found in tea bind with caffeine, slowing its absorption.
In addition, tea (and the Boletus radius mushroom) contains a unique amino acid, L-theanine. This amino acid increases alpha brain wave activity, which has a relaxing effect. And, theanine works synergistically with caffeine to improve brain function and attention.
How Much Caffeine Is in Your Teacup?
Many factors come into play, so there is no simple answer. These all affect the caffeine levels in tea:
- Type of tea plant (C. sinensis var. assamica has more caffeine than C. sinensis var. sinensis)
- Origin of plant (clone has more caffeine than seedling)
- Age of plant
- Stress on the plant (e.g., caused by pests)
- Soil conditions (e.g., higher nitrogen level means higher caffeine level)
- Growing season (the faster the plant grows, the more caffeine)
- Amount of shading the plant receives (shading increases the caffeine level, but also increases the theanine level, which offsets the stimulant effects of caffeine)
- Which leaves are plucked (buds and young leaves have more caffeine)
- How the leaves are processed after plucking (e.g., duration and temperature of withering, duration of oxidation)
- Particle size (e.g., fannings vs whole leaf)
- Brewing, which includes:
• temperature of water
• amount of tea
• method of brewing (e.g., loose, teabag)
• brewing time
• which infusion it is
- Amount consumed
Can You Do Anything About the Caffeine Level?
You cannot “wash” caffeine out of tea—nor would you want to remove caffeine in this way because caffeine and flavor go hand in hand. You would need to infuse a teabag, for example, for over five minutes to remove 80% of the caffeine—and clearly the second infusion would have no flavor left!
Plus, other substances that contribute to flavor and health benefits (such as polyphenols) are also extracted quickly, another reason that we want to drink the first brew and not discard it.
With loose leaf tea, the flavor—and the caffeine—is maintained over multiple infusions, particularly with whole leaves. For those teas that have been shaped into pearls or rolled, each infusion will unfurl the leaves more fully, releasing additional caffeine.
However, you can limit the amount of caffeine released by lowering your brewing temperature by 5° with each infusion. A bonus is that this also decreases bitterness in your brew (both caffeine and tannins are naturally bitter tasting, and both are released by hot water).
For our decaffeinated teas, the caffeine is removed with naturally occurring carbon dioxide (CO2). In its supercritical state, the small molecules of CO2 attract the caffeine molecules; the resulting linked CO2-caffeine is filtered out, leaving both the flavor and the polyphenols of the tea largely intact.
Please note that decaffeinated teas are not caffeine free. A small amount of caffeine always remains after the decaffeination process.
However, TeaHaus offers many naturally caffeine-free fruit teas, rooibos, and honeybush. Many herbal tisanes are caffeine free as well.