Dolfin Earl Grey Chocolate

Earl Grey Chocolate

Dolfin Earl Grey Chocolate

I picked up this packet of Dolfin Earl Grey Chocolate in Belgium. Plenty of chocolatiers are making tea-flavoured chocolate but it’s still not that common to find here (apart from matcha Kit Kats!).

I’m definitely not an expert but buying chocolate in Belgium seemed like a safe bet. This is dark chocolate but only has 52% cocoa. On the positive side, the flavour of earl grey is subtle, it’s not overly sweet and the tea in the chocolate makes a natural crunch that is pleasant. The outer packaging is not bad either with its cute resealable envelope pouch. On the negative side, the chocolate is not smooth but grainy and doesn’t melt easily so I ended up chewing the chocolate. I found the quality of the chocolate too distracting to enjoy the taste and unusually (for me) the bar has been left untouched for several weeks. I think Earl Grey has the potential to go very well with dark chocolate but this Dolfin bar just didn’t pull it off.

Caffeinated: How Our Daily Habit Hooks, Helps and Hurts

Murray Carpenter approaches caffeine as a drug because most of us take it every day, it has predictable physiological effects and we are dependent on it. His new book Caffeinated: How Our Daily Habit Hooks, Helps and Hurts (Hudson Street Press) was launched on 13 March and sounds like it will make for a very interesting read:

  • Women on birth control metabolize caffeine twice as slowly—which means they get double the jolt from the same cup of coffee
  • Smokers metabolize it twice as fast so they needto up their intake to get the same buzz
  • Some people are genetically predisposed to metabolize caffeine slowly and they will be extremely sensitive to caffeine
  • 100 milligrams of caffeine daily is enough to get an adult dependent
  • 250ml of cola has ~24mg of caffeine but Coke used to contain ~80mg of caffeine (the same as Red Bull today)
  • Caffeine withdrawal-symptoms can include lethargy, irritability and headaches
  • Post-operative headaches are linked to caffeine withdrawal
  • Migraine, hangover and cold medicines often include caffeine and caffeine suppositories can be used medicinally
  • Extroverts get more cognitive enhancement from caffeine
  • A tablespoon of pure caffeine would kill you
Caffeinated Owls - Dave Mottram (Image Source)

Caffeinated Owls – Dave Mottram (Image Source)

 

As I previously wrote, there have been several papers written on the effect of caffeine on sleep disruption and even more papers written on the positive and negative effects of caffeine on other health issues. A major problem in this type of research is that the papers tend to use very different values for the caffeine content in beverages and foods  and most ignore the effects of other substances like theobromine, tanninic acid, caffeol etc.

For tea in particular it can be hard to pin down the precise caffeine content. Preparation plays a large role and differences in the time and temperature of steepings, the size of the tea leaf and the type of tea used will all influence the caffeine content of tea. The plant variety, soil, nutrients, picking season and the part of plant used will also play a role.

After a lot of searching, I eventually collected some reliable information on the caffeine content of tea.

[Note: moderate caffeine use is generally considered to be 200 – 300 milligrams per day]

 

Tea (~200ml after one steeping of three minutes)

Chinese white tea – 75mg

Darjeeling white – 56mg

Indian Green – 59mg

Kenyan Green – 58 mg

Chinese Oolong (Ti Kwan Yin) – 37mg

Assam (FTGFOP) – 86mg

Darjeeling Black (SFTGFOP1) – 54mg

 

For comparison here are some for coffee and other beverages:

Coffee (~200ml)

Coffee (ground roasted) – 115mg

Coffee (instant) – 80mg

Cola – 20mg

Decaffeinated coffee – 4mg

Espresso, single shot – 75mg

Espresso, double shot – 150mg

Red Bull (250ml can) – 80mg

 

Chocolate

70% Green and Black dark chocolate (30g) – 4.5mg

Green and Black milk chocolate (30g) – 2mg

White chocolate (30g) – 0mg

Caffeine

I was reading an old article from Bord Bia that said that tea consumption was on the rise at night-time. The reason given was that “people are at home more often and tea is a comforting affordable reliable beverage”.

There have been several papers written on the effect of caffeine on sleep disruption and even more papers written on effect of caffeine on other health issues (good and bad). A major problem in this type of research is that all the papers tend to use very different values for the caffeine content in beverages and foods.

There are plenty of reasons for the variations. Preparation plays a large role and differences in the time and temperature of steeping, the size of the tea leaf and the type of tea used will all influence the caffeine content of tea. The variety of plant, care of the plants, soil nutrients, picking season and the part of plant used will also play a role.

Caffeine Crystals under the microscope

Caffeine Crystals under the microscope (Source)

Caffeine is a white, odourless crystal that occurs naturally in coffee, tea and chocolate and is added to colas and energy drinks. After a lot of reading, here is a summary of caffeine content in tea from sources that seems reliable:

Tea (~200ml after one steeping of three minutes)

Chinese white tea – 75mg

Darjeeling white – 56mg

Indian Green – 59mg

Kenyan Green – 58 mg

Chinese Oolong (Ti Kwan Yin) – 37mg

Assam (FTGFOP) – 86mg

Darjeeling Black (SFTGFOP1) – 54mg

 

For comparison here are some for coffee and other beverages:

Coffee (~200ml)

Coffee (ground roasted) – 115mg

Coffee (instant) – 80mg

Cola – 20mg

Decaffeinated coffee – 4mg

Espresso, single shot – 75mg

Espresso, double shot – 150mg

Red Bull (250ml can) – 80mg

 

Chocolate

It seems to be generally accepted that there are 6mg of caffeine per 30g serving. But it seems to vary a lot:

70% Green and Black dark Chocolate (30g) – 4.5mg

Green and Black milk chocolate (30g) – 2mg

White chocolate (30g) – 0mg

Cadbury dairy milk (28g) – 15mg

Herbal tea

Herbal tea – 0mg

(Note: other substances like theobromine, tanninic acid, caffeol also play a role)

 

I found it surprising how high the caffeine content of green tea is. Many claim that green and white tea have less caffeine than oolong or black tea because of the minimal oxidation. It seems to be well-proven now that this is not the case. White tea in particular uses the bud of the plant which has been shown to have a higher caffeine content that the leaf. I guess most people wouldn’t have a can of coke before bed but I wonder if they know that a Chinese white tea has three times as much caffeine?

With a few exceptions, herbal tea or tisanes have no caffeine at all. That includes Rooibos so there is a huge selection of tea alternatives for night-time. I’ve been going through a rough time with sleep lately so now I only drink tea up to about 3pm and right before bed I drink hops tea. It seems to really help. And no, by hops tea I don’t mean beer though sometimes that helps too :-).

 

Main Sources:

Barone JJ, Roberts, H.R. (1996), Caffeine consumption, Food and Chemical Toxicology, Volume 34, Issue 1, January 1996, Pages 119–129.

Richardson, B. (2009), De-bunking the At-Home Decaffeination Myth Story, Fresh Cup January 2009

Chin JM, Merves ML, Goldberger BA, Sampson-Cone A, Cone EJ. (2008), Caffeine content of brewed teas. J Anal Toxicol. 2008 Oct;32(8):702-4.