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.

 

Nepalese tea – First Flush SFTGFOP

Until 2000, Nepal’s tea exports accounted for only about 150,000 kg per annum. However, due to liberalisation, the Nepalese tea industry has witnessed an exponential rise in tea exports in the last ten years. At present, Nepal produces approximately 18 million kilograms of tea per annum on an area of 18,149 hectares. The climate, soil and unpolluted air in Nepal are said to be ideal for tea and production is incentivised through government subsidies for machinery. CTC manufacturing accounts for 87% of production. The remaining 13% of Nepalese orthodox tea has a reputation for being outstanding.

Nepal First Flush Side ViewI received some tea samples last week from a Nepalese colleague who was kind enough to bring some back from his travels. There were a number of samples but one in particular caught my eye: a first flush SFTGFOP Black tea. As a first flush it was probably picked sometime in March or April and these teas are generally a milder and gentler tea than the leaves that are plucked later in the year.

Nepal First Flush The leaves are short and wiry and although the leaves are mostly brown you can see from the photo the white buds and some partially oxidised green leaves. The smell of the dry tea is strong and grassy.

Preparation: To prepare this tea, I put 3g of the tea in a gaiwan. After rinsing the leaves, I add the boiling water for 30 seconds but I felt it needed a little longer so I left it for about 40 seconds.

First steepThe first cup is sweet-smelling, light yellow and the taste is crisp and light with that very distinctive musky taste. Pungent is a word that suits this tea well (especially the second and third steeping) but not pungent in the usual sense of overpowering sourness but softly pungent as an interesting background that deepens the taste. This tea held well for six steepings with increasing steeping durations each time.

Among the rest of the samples is an Autumn SFTGFOP and I’m looking forward doing a comparison taste in the coming days.

 

Grading Black Tea

I’ve been tasting a lot of black tea over the past couple of weeks but before I start talking  TGFOP and BOP, I thought it would be worthwhile to have a reference article to go through one of the most common grading systems for black tea. The grading system has four separate scales that are based around the size of the leaf. Size is not directly correlated to quality but it is used as an indicator.

 ORTHODOX TEA

Whole leaf – the leaf remains intact during production (not broken or torn)

  • SFTGFOP – Special, Fine Tippy Golden Flowery Orange Pekoe
  • FTGFOP – Fine Tippy Golden Flowery Orange Pekoe
  • TGFOP – Tippy Golden Flowery Orange Pekoe
  • GFOP – Golden Flowery Orange Pekoe
  • FOP – Flowery Orange Pekoe
  • FP – Flowery Pekoe
  • OP – Orange Pekoe

Broken leaf – the leaf has been torn or broken

  • GFBOP – Golden Flowery Broken Orange Pekoe
  • GBOP – Golden Broken Orange Pekoe
  • FBOP – Flowery Broken Orange Pekoe
  • BOP – Broken Orange Pekoe
  • BPS – Broken Pekoe Souchong

Fannings are broken pieces of tea that have a granular texture. The small pieces mean that they release their taste and colour quickly, which makes them suitable for teabags.

  • FBOPF – Flowery Broken Orange Pekoe Fannings
  • BOPF – Broken Orange Pekoe Fannings
  • FOF – Flowery Orange Fannings
  • GOF – Golden Orange Fannings
  • PF – Pekoe Fannings

Dust is a powder tea that is smaller in size than fannings.

  • OPD – Orange Pekoe Dust
  • BOPD – Broken Orange Pekoe Dust
  • PD – Pekoe Dust
  • D – Dust

 

CTC  stands for Crush Tear Curl and is a modern manufacturing method where the tea leaf is chopped to small uniform pieces while it is being oxidised to black tea. This gives small granular pellets. There is a separate grading system for CTC tea that is also broken down into Broken Leaf, Fannings and Dust.

A few notes on the terms:

Orange – Orange does not refer to the citrus fruit or to an orange flavour. It comes from “House of Orange” which was the royal Dutch family where the finest teas were presented in the 1600s.

Tippy refers to the proportion of buds in the tea

Flowery mean that larger leaves as well as buds are present

Tea bag issues

Tea bags have been getting some bad press lately. Well, tea bags are always getting bad press for their contents but this time it is the bag itself causing the problem.

Silken TeabagsIt seems that the tea bags that are described as “silken” are actually made with plastic. Some of these plastics are food-grade nylon or polyethylene terephthalate (PET) but they have a melting point of ~250 °C and are generally not considered harmful to health. However, an article appeared in the Atlantic a couple of weeks ago that said that the molecules of these plastics would start to break down at a lower temperature (~76 °C) which could allow the bags to leach out toxins. The example in the article was a Lipton Pyramid Tea Bag made of PET but there was no concrete evidence of toxicity and no measure of toxins.

Another type of plastic used in these silky tea bags is polylactic acid (PLA), a biodegradable plastic made from cornstarch (which can be genetically modified or not). This bioplastic is commonly used as the input material for 3-D printers and doesn’t seem to carry the same health concerns as PET. While technically PLA is biodegradable and may well break down into its constituent parts (carbon dioxide and water), it needs an industrial composting facility heated to 60 °C and the addition of digestive microbes. In a compost bin, or in a regular landfill, there is no evidence that it will break down there any faster than any other form of plastic (source).

The bad news didn’t stop there though. Apparently paper tea bags may have similar culpability.  Many paper bags are treated with epichlorohydrin as a paper reinforcement to stop the tea bag tearing.  Epichlorohydrin is also used to make insect fumigant and is considered to be a carcinogen and moderately toxic. The exposure limits set by WHO are 0.4 μg/litre. I’m assuming that moderate tea-drinking with these tea bags would leave you well below the exposure limits but I can’t find confirmation of that.

Silken TeabagI tend not to give too much credence to health warnings like these but it might be worth checking the packaging if you use a lot of tea bags.

Da Hong Pao (Royal Red Robe)

I bought this Da Hong Pao (year & season unknown) at the Berliner Teesalon nearly 4 weeks ago but only got around to tasting it last weekend.

Da Hong PaoThis Oolong tea is produced in the Wuyi mountains of Fujian, China. See previous post on Da Hong Pao for the legend associated with this tea. Strip-style Oolongs like this one are unique to China and are easy to spot in a line-up because of their dark colour and stemless twisted leaves.

IMG_5820Preparation (see post here about steeping): To prepare this tea, I put 5g of the tea in a warmed clay teapot. After rinsing the leaves, I add 150ml of water that is just below boiling (when it makes the rumbling sound) and let it rest for 30 seconds. The leaves are not as dark as this type of Oolong would normally be and the tea is a golden yellow on the first steeping. The second and third steeping are darker but never get to the deep amber that would be expected from heavy roasting. There is an earthy smell and definite sweetness in the taste. It is not unpleasant to drink but it lacks the full bodied, rich peaty flavour that this type of tea should deliver. I steeped this tea five times, increasing the steeping durations each time.

The tea €15 for 50g and I consider that too expensive for the quality of this tea.