Yixing stoneware

I mentioned Yixing in this post on ceramics but these stoneware teapots warrant their own post. Yixing teapots (zisha) are unglazed porous stoneware teapots made from clay that comes from the region of Yixing in Southern China. The Yixing clay has a very unique, iron-rich composition and the resultant stoneware is durable and a good insulator. More importantly, Yixing clay absorbs the flavour of its contents and over time develops a lining of tea deposits that enriches the flavour of tea.  Over years of use, the teapot changes in colour and flavour and these teapots are valued because of the fine teas they have brewed. Each Yixing teapot can only be used for one type of tea and it needs to be seasoned before it is used to clean it and to remove any firing/baking smells.

Yixing teapot

Yixing teapots date back to the 11th century but became popular in the Ming dynasty (1368-1644) when tea leaves instead of powder become popular. Today they are mostly used for pu-ehr and oolong tea and there is no doubt that tea from these teapots is noticeably richer and more interesting. Making pu-ehr in a Yixing teapot is a little bit like serving white wine (or champagne 😉 ). Of course you can serve white wine warm in a plastic cup but if you have spent good money on a nice bottle, you will want to put in an effort to chill it and serve it in a proper wine glass to bring out the flavour.

 

Judging the authenticity of a Yixing teapot can be difficult. For this reason, I tend not to buy expensive Yixing (especially online). The tell-tale signs of real Yixing are solid dull colour but with sparkling flecks throughout. It has a rough surface (not smooth or shiny) and the inside should smell of earth rather than chemicals.

 

There are a huge variety of shapes and sizes but generally speaking they fit into three categories.

  1. Geometric forms – this is the most popular category and cubes and spheres are the most popular geometric forms
  2. Natural – these teapots incorporate elements of nature either by sculpting the teapot based on a natural element or by decoration
  3. Striated – usually the body resembles a flower by building symmetrical segments (petals) into a unit

Decoration (if used) usually takes the form of engraving, inlaying or slip painting.

The price depends on the quality of the clay (zisha or mixed), manufacturing (handmade or moulded), age, size and shape. It will range from €20 for a basic moulded teapot to hundreds of thousands for antique artisan teapots.

The video below shows Chinese yixing artist, Zhou Guizhen, creating a teapot:

 

 

When you drink the water, remember the spring (proverb)

Tea is ~99% water so there is no doubt that the quality of that water will make a difference to the flavours of the cup.
Tap water here is very “hard” so it leaves limescale on teapots and kettles and doesn’t taste great. Buying water is a complicated business though. Bottled Water is so heavily marketed it is difficult to disregard the branding and get a true comparison of the products. Here is a breakdown of the main types of water that are found here in Ireland:

  • Public mains water – goes through a set of treatment process before it is distributed to ensure that it is filtered and sterilised and fit for drinking. The main stages in water treatment are screening, flocculation, sedimentation (clarification), filtration, chlorination, fluoridation and pH adjustment. Chlorine is added to kill bacteria and afterwards ammonia is sometimes added to the water to reduce the taste left by the chlorine. Fluoride is also added to prevent tooth decay.
  • Filtered water – Filtering tap water with a simple jug filters will remove visible solids and most of the chlorine. They will improve the taste but it will not remove fluoride or change the mineral content significantly and so it will not soften the water.
  • Purified/distilled water –Water that has been produced by a process such as distillation, deionization, reverse osmosis or other process. It will have no minerals.
  • Spring water – Comes from underground source but naturally flows on the earth’s surface. It is naturally filtrated by passing through layers of rocks and soil. Spring water may be treated by ozonation, UV light and chlorination and unlike mineral water does not need to have a stable composition.
  • Natural mineral water – Natural mineral water come from natural mineral water springs and contains at least 240 parts per million Total Dissolved Solids (TDS). Natural mineral waters are pure at source and are distinguished from other types of bottled water by its constant level of minerals. It originates from a protected underground water source. No minerals or chemical preservatives may be added to the water.

Tasting water and matching it with food is a whole other world (see Bottled Water of the World). There is a range of factors that are considered in the taste of water but the mineral composition and the acidity level (pH) are two of the main factors for still water. Acidic waters have a pH of less than 7 and alkaline water have a pH greater than 7. Alkaline water tends to taste sweeter and softer than neutral or acidic water. The Total Dissolved Solids (TDS) is the sum total of all the mineral in the water (most commonly Calcium, Magnesium, Sodium and Potassium). These minerals give water a heaviness and it correlates with the hardness of the water.
Below is an interesting graph of pH and TDS plotted for the main water brands (source).

Mineral Water Comparison (Source)

Mineral Water Comparison (Source)

For tea making, we are looking for water that is not too mineralised and doesn’t have any dominant mineral that stands out. Distilled water (that has no minerals) is not good either because it is too flat. Ideally tea water would be neutral pH 6-8, have no chlorine and have total dissolved solids (TDS) of ~100ppm.

Still confused about what’s what with water? Interestingly, there are some good explanations in Bret Easton Ellis’s book “American Psycho” (excerpt here)!

Japanese Green Teas

I decided yesterday to taste two Japanese green teas together so I could compare them side by side. The first tea, a Sencha, is the most common type of Japanese Green Tea and would be drank on a daily basis in most Japanese homes.  Sencha is harvested in the Spring from the upper leaves of the tea plant that have been in direct sunlight.

The second tea, a Bancha, is also a common every-day tea in Japanese homes. It is made from later harvests of the tea plant or from the lower leaves and stems. It is therefore a coarser tea and it is considered to be a lower quality and less expensive tea than Sencha.

Although Sencha means roasted tea, both Sencha and Bancha are steamed and rolled soon after harvesting. The difference between the two teas is the quality of the leaves used. Where Bancha has come from lower, older leaves it will have less caffeine and less catechin (antioxidant) than sencha. However, where Bancha has come from a later harvest of upper leaves, it could have more catechins. Below is a short video from My Japanese Green Tea of the steaming, drying and rolling process at a Sencha plant


Sencha is considered a fussy tea in terms of preparation. While Bancha is can be prepared with boiling water for 30 seconds, boiling water on Sencha will bring out the bitterness and kill the flavor so Sencha needs a water temperature of ~80°C and a longer brewing time. For my comparison experiment, I decided to brew them both at 80°C for 2 minutes. If you don’t have a thermometer or a thermostatic kettle (I used my new Breville!), you can guess 80°C by waiting for small bubbles to appear on the inside of the kettle.  The bubbles need to be the size of shrimp’s eyes as opposed to crab eyes (85°C) or fish eyes (90°C)!

Looking at the dry leaf, both are flat leaf, emerald green. From the pictures below you can see that the Bancha includes stems. It probably isn’t obvious from the photos but it is clear when you have the leaves in front of you that the Bancha is also less regular and is more dusty. The Sencha has a deep musky aroma with some sweetness while the Bancha is more grassy with a malty sweetness.

Bancha leaves

Bancha leaves

Sencha Leaves

Sencha Leaves

To prepare these teas, I put 3g of tea in a warmed ceramic teapot and add 150ml of water at ~80°C. I steep for 2 minutes. Both give a yellow/green liquor and both are cloudy but the Bancha is noticeably more cloudy. The taste of the Sencha is bright and grassy with a background meaty taste (unami). There is a sweetness at the start that is matched by a bitterness and astringency that comes out later. The Bancha is grassy and malty sweet with less of the meaty flavor and noticeably less astringency. Both are light and refreshing but I would describe the Bancha as milder, gentler green tea.

I combined each with a small pinch of salt beforehand to see how it brings out the sweetness. For the Sencha it mutes the astringency and gives a rounder flavor but I didn’t notice a big difference with the Bancha. Both of these were samples so I don’t know the price but one of my local tea houses has a Sencha for €11/100g and a Bancha for half of that (€5/100g).

Guinness World Records for Tea

I’m away for this week without access to technology of any kind (no email, phone, internet etc.) so this is a scheduled post that I wrote last Thursday.  I was in holiday mode when I wrote this and was looking for something fun so here are some world records on tea:

 

Largest cup of Tea
The largest cup of tea is 4000 litres (7039.01 pt) in volume and was produced by GlaxoSmithKline Beecham (Private) Ltd (Sri Lanka) for Viva, at Burgher Recreation Club grounds in Colombo, Sri Lanka, on 9 October 2010. The tea cup was named the “VIVA” tea cup. The tea cup itself measured 10 ft in height and 8 ft in width. Six 2000 watt heaters and a stirrer powered by motors and generators maintained the temperature of the tea at 75 degrees celsius.

 

Most cups of tea made in one hour (team of 12)
The most cups of tea made in one hour by a team of 12 was 725 and this was achieved by Devonshire Tea Limited (UK), at ‘Flavour Fest’ festival, in Plymouth, UK, on 19 August 2011. This attempt took place on day one of the event called ‘Food Fest’ in Plymouth.

 

Largest tea bag
The largest tea bag weighs 120 kg (264 lb 8.8 oz) and was achieved by All About Tea (UK) on board HMS Warrior in Portsmouth, UK, on 16 November 2011. The tea bag measures 2.48 m (8 ft 1.64 in) in length and width.
This event was in celebration of GWR Day 2011. The tea used is called ‘Portsmouth Tea’ and is a blend of African and Indian teas. The tea bag, which was made from cotton, is capable of making over 50,000 cups of tea.

 

Largest collection of tea bag tags:
The largest collection of tea bag tags is 839 tags and belongs to Daniel Szabo (Hungary), in Budapest, Hungary, on 4 September 2011.
The collection was displayed to the public at SzeptEmber Feszt 2011 and has been featured in several news articles.

 

 

Largest Tea Party
The record for the largest tea party is 32,681 participants and was achieved by Dainik Bhaskar (India) for the City of Indore, at Nehru Stadium, in Indore, India, on 24 February 2008. The official brew for the event was Brooke Bond Red Label and the event was supported by Tea Board of India.

 

Largest Tea Cosy Knitted
The largest tea cosy was knitted by members of the public, Bupa care homes residents across the UK and resident care homes in Spain and New Zealand at Ashley Park nursing home in Guilford, UK, on 9 April 2009. The final tea cosy included 1924 squares in total. It stands at 3.9 metres high and 11.1 metres in Circumference.

 

Largest Tea Monument
This isn’t in the Guinness World Records but World Record Academy says that “MEITAN, China–At 73.8 meters in height, and featuring a floor area of over 5,000 square meters, this unique teapot museum of Meitan, south west China, sets the new world record for the Largest Teapot Monument”

Let the record show….

In case there is an impression that I sit around drinking only good tea, let the record show that I drink my fair share of foul liquids. In the interest of not turning the site into a rant I have gathered some of the worst offenders into one post. Some are bad teas but some are just teas that do not appeal to my palate.

Pu-ehr AntiqueThis first tea is probably the worst of the lot so let’s just get it over and done with. It is a pu-ehr that was stupidly bought by me in a supermarket in France. The dried leaf of this tea has off-notes that is a mix of rancid and tar. If the aroma of the dried leaf is so strong it doesn’t bode well for the liquor but I brewed it anyway. It is undrinkable and I mean undrinkable in the sense of I’m afraid to put the dried leaves into the compost-bin in case it contaminates the compost and I end up eating carrots next year that taste like this tea. As pu-ehr goes, it wasn’t at all expensive (I think around €7-8) but I hate to think of someone who normally buys black tea deciding to experiment with this loose leaf pu-ehr. I can see them now mentally filing pu-ehr into the same category as cod liver oil.

 

 

Pu-ehr lemonThe second offender also involves pu-ehr but in this instance it is more subjective. I very rarely drink flavoured tea and I cannot imagine a situation where I would pick up a packet of lemon pu-ehr and hand over cash for its purchase. I’ve come to the conclusion that it was a a free sample that I picked up somewhere. It tastes unsurprisingly of lemon but it is artificial and dull and is just so wrong.

 

 

This next one is completely subjective and I’m sure plenty of people would like it. I visited Nigiro Tea last year when I was in South Africa to buy some of their famous “Orange & Spices” rooibos which is flavoured with cloves, cardamom, cinnamon and orange. I could have cried when they told me that they were all out and would not be restocking until the following week. I wanted to buy one of their rooibos teas to take home so the shop assistant recommended the caramel rooibos. My conspiracy theory says that she knew I was flying out the next day and figured that the chances of me calling back to complain and return any tea were low so she sold me the dud tea that wasn’t selling. The less paranoid side of me says that some people might actually like this sickly sweet blend.

 

Immune BoostThe Immune Boost from Tea Palace is next on the list. It has a nice list of ingredients: orange peel, ginger, echinacea and ginseng but the taste is bitter and unpleasant. This tea usually ends up in a competition with Lemsip for the award of worst tasting medicinal fluid. In case my taste buds were altered by being sick, I tried to drink this when I was well again but the outcome is the same. It wasn’t bought with flavour in mind but my immune system will have to do without this particular boost.

 

And finally, cold infusions. Yesterday seemed like a good day to embrace the concept of cold infusion after Met Éireann announced that it was the hottest day in Ireland for seven years. I’m still a little bewildered at the idea of of making tea from cold water but I was ready to be the early adopter and started with a green tea/rooibos/lemon myrtle mixture. It doesn’t taste like green tea or rooibos. It is just water with a dull hint of citrusy flavour. I could drink this as a water replacement but definitely not as a tea replacement so after being so open-minded in the build-up to the tasting, I have made the snap decision that cold infusions are not for me.

It is difficult to avoid the occasional cup of bad tea but most of the incidents above  could have been avoided by sticking to my guiding principles of tea-buying 😉

  1. Don’t expect to find good quality loose leaf tea in supermarkets
  2. Don’t fall for the sales pitch/taste before you buy
  3. Tea is not a medicine
  4. Tea needs to be made with hot water

 

Rooibos health updates

I have written previously about some of the research on rooibos but since then I came across a few new pieces:

  1. A study looking at the potential of Rooibos to increase the shelf life of Ostrich meat patties!
  2. A piece of on-going research involving the influence of Rooibos on prostate cancer.
  3. A study on the liver-related benefits of Rooibos and Red Palm Oil that was published in Evidence-Based Complementary and Alternative Medicine.

The press releases around the last one grabbed my attention by saying that this research proved that rooibos could improve liver function and protect against oxidative damage to the liver.

Rooibos Natural

 

The inclusion of Red Palm Oil (RPO) in the title sent me off on a tangent to find out more about it. This in turn led to a diversion down the road of Palm Oil and Oxidised Palm Oil. Several hours later I had lost most of Saturday and was so far down a byroad of nutritional science that I didn’t think I would ever find my way back.  But the detour did turn up some interesting information albeit mostly unrelated to rooibos or tea.

It seems that palm oil comes from the palm fruit and is popular with food manufacturers because it is cheap and after processing has a long shelf life, is odourless and is solid at room temperature.  Oxidised palm oil is commonly used in food products and the oxidation seems to be responsible for the generation of toxicants and the introduction of “reproductive toxicity and toxicity of the kidney, lung, liver and heart” (Edem, 2002).

Red palm oil on the other hand comes from the same part of the palm tree but is red in colour from its high concentration of carotenes. Unprocessed, it contains high amounts of antioxidants and is associated with cardiovascular and nutritional benefits. At moderate levels, RPO is believed to promote the utilisation of nutrients, improves immune function and activate hepatic drug metabolising enzymes (Oguntibeju, 2009). Nutritional supplementation seems to show promise in lowering LDL cholesterol and experiments on rats show improved protection of the heart. [For entertainment see Dr Oz’s dramatic endorsements of RPO].

This new rooibos study worked from the basis that both rooibos and RPO had been shown to be liver-protective and it aimed to investigate if the positive effect could be heightened by combining rooibos and RPO. The results suggested that rooibos and RPO both protect the liver but the level of protection was only equal to that of either rooibos or RPO so a synergy in the combined protective effects could not be shown. Unfortunately, the study was carried out on rats so we still can not say for sure that a similar liver-protection effect happens when humans drink rooibos.

In fact, the only report involving rooibos and human liver that I found was a report in the Eur J Clin Pharmacology about a 42 year old patient with a previous medical history who experienced signs of liver damage after starting to drink rooibos. Clearly, a single case is not a basis for any kind of conclusion but it does indicate once again the need for human studies to confirm health benefits.

Tea and Food Pairing

Micro Salad

Micro Salad (Source)

Last summer, I was lucky enough to meet one of the scientists behind molecular gastronomy, Hervé This. I also attended his session at the Euroscience Open Forum entitled “Science and the future of cuisine” where he (along with Mark Post and Bill Yosses) discussed molecular cuisine and the new trend in scientific cooking called note-by-note cuisine. The session was full of fascinating examples of this new cuisine but also covered the practicalities of sustaining the human race by “creating” vegetables and meat in the lab. It was an unforgettable session and tasting the chocolate mousse that was produced without cream or eggs sealed the deal!

In particular though, it drew my attention to the application of science for understanding taste and flavour so when I attended the World Tea Expo a few weeks ago, I was excited to hear Virginia Utermohlen (Cornell University) and Renée Senne talking about their scientific approach to pairing food with tea. Virginia started with the basics of taste and flavour and discussed how the chemicals in tea bind to receptors in our mouths and nose. The session then focussed on the effect that food has on the taste of tea – how some foods will mute the taste of tea while others will enhance it. I was expecting the session to be based around a molecular matching approach but Virginia’s approach was mostly based on trigeminal receptors (for heat and coolness). Cinnamon and mint were used to illustrate the power of these receptors. We were each given a cinnamon sweet which is considered to be “heat” on a taste/temperature scale so it gives a sense of warmth after binding to its receptors. After the taste had developed we took the sweet out of our mouth and replaced it with a mint. The “coolness” of the mint turns off the heat receptors and gives a sense of cold when it binds to its own receptors so the cinnamon taste was completely replaced with mint. After the mint was removed the heat receptors become active again and the heat of the cinnamon came back as residual cinnamon in the mouth was picked up.

Trigeminal Receptors

Thermal Nociceptors (Source)

From there, we went on to apply the model to Black (hot), Oolong (warm) and Green (cold) tea. The general premise was to use food of similar heat or coolness together to avoid unpleasant tastes and to allow the tea and the food to complement each other and enhance each others flavours. So Oolong (warm) could not be mixed with Cardamom (hot) because the hot spice would mute the taste of the warm drink. Crème fraiche going well with Mexican food is an example where flipping hot and cold can result in a positive effect. It makes sense to some extent but still didn’t clear up some of the well-known anomalies of molecular matching (e.g. strawberries clashing with black tea and sugar clashing with green tea). It is an interesting model to consider alongside other food pairing methods and certainly goes a long way to explaining why I like my chilli-chocolate with black tea.

Ceramics

Bone Ash

Ingredients for Bone China (Source)

Someone told me during the week that some vegetarians and vegans don’t use bone china teacups. I wasn’t aware of this but it made for some interesting reading about the differences between bone china, porcelain and stoneware. I found out that bone china is made from a translucent white ceramic clay but it is set apart from fine china by containing a minimum of 25% bone ash. The animal bones are burned and ground before it is added to the clay. Bone China tends to be slightly translucent in nature. It is easier to manufacture than fine china, is strong, does not chip easily, and has an ivory-white appearance.

Porcelain - Sue Paraskeva

Porcelain Sue Paraskeva (Source)

Porcelain is a type of ceramic that is made from kaolin clay. It is also referred to as china or fine china. Kaolin is white clay that retains its white color when fired. It is usually covered with a clear glaze. Porcelain becomes vitrified (glass-like) during the second firing of a two-fire process at temperatures of over 1,300 degrees Celsius. It is considered “vitrified” if it absorbs less than 0.2 percent of its own weight. Porcelain tends to be finer quality than stoneware.

Yixing Clay Teapot

Yixing teapot (Source)

Stoneware is also a type of ceramic but differs in color and also in the way it is fired. Porcelain is fired twice but stoneware is vitrified during a single firing and the temperature is a little lower than used for Porcelain. The finish is warmer in color than Porcelain. An easy way to tell porcelain from stoneware is to look at the bottom rim, porcelain will be white whereas stoneware will be a natural color with a colored glaze on top. Yixing teapots (the famous unglazed porous teapots) are a type of stoneware that is made from clay from the region of Yixing in Southern China.

Finally, earthenware, again a type of ceramic, is made from white porous clay that is fired at a low temperature. It cannot hold water and is more chalky and easier to chip than stoneware. Terracotta is a type of earthenware. It is usually more suited to decorative use rather than household use.

Ode to my Bodum cup

The Bodum Tea for One

The Bodum Tea for One (Source)

Ok, I can’t write an ode but I do love this cup and I only realised how much when I tried replacing it. I don’t use this cup for preparing real tea at all but the Bodum “tea for one” is perfect for herbal teas.

Things I love about this cup:

  • It is double-walled with a vacuum between the walls so it keeps the liquid inside hot (especially with the lid on)
  • The double wall means that the outside doesn’t get too hot to handle
  • It came with the brew basket which has a mesh that is fine enough to prevent even small particles getting through (handy for when you grind herbs)
  • Some herbal teas need to have their vapours contained in order to maximise benefits and the lid is perfect for that.
  • The size of the brew basket means that bulky herbs are not a problem
  • The glass cup allows me to gauge how strong the tea is
  • The lid doubles as a saucer for the brew basket to stop it dripping
  • It doesn’t have a handle – weird I know, but I like that it doesn’t have a handle. It’s more symmetrical.
  • I’ve had this for over five years, use it three or four times a week and it is still not broken or chipped.
  • It is easy to clean. I’ve always hand-washed mine but it is dishwasher safe.
  • It is a good size for herbal teas (350ml)
  • The brew basket doesn’t absorb the flavour of the tea so you don’t get the flavour of the last herb that was prepared in it.
Yo-Yo Set

Yo-Yo Set (Source)

The “tea for one” is no longer available on the Bodum website and seems to be replaced with the Yo-Yo set. It looked like it might do the trick but it didn’t. It is not double walled and the lid is smaller than the cup so there are gaps all around that let out heat and vapours. A more minor issue is the handle. It just looks wrong but I would get over that if it were not for the other two problems. I foresee a bleak future for this cup at the back of the top shelf.

The situation is not completely hopeless. I can still buy the double-walled glasses on their own and try to find a brew basket and lid that fits them afterwards. In the mean time though, after five years of taking my bodum cup and strainer for granted, I’m now afraid to use it in case I break it.