Tea Tasting

Dry Leaf

The dry leaf is generally placed on a piece of white paper and the following points are recorded:

. Grade.

. Colour of the leaf.
. Make and style.
. Nose.
. Feel.

Grades

The teas have to be classified as per their grades.

Colour of the Leaf

Tea taster in workGreyness in tea is not desirable as it denotes faulty manufacture; generally during sorting. The thin and varnish like coating on the dry leaf is rubbed off and results in a grey colour. This coating is soluble in water and plays an important part in liquoring properties. If absent, the tea must necessarily have been deprived of its fullest liquoring capabilities. A brown appearance, on the other hand, is often unavoidable with very tippy tea. The reason for this is the hair growth down the shoot, which has been picked for manufacture. The second leaf may have a quantity of hair insufficient to produce a golden appearance known as tip but sufficient to discolour the leaf to that of a brownish colour. Also during rolling some hair may be rubbed off the bud and possibly the first leaf and deposited on the coarser leaf. During firing this hair is affixed to the leaf and results in a brownish leaf appearance.

Some teas produce a reddish appearance at certain times of the year. This is generally found during the autumnal period when growth is slow and the tea shoots become less succulent tinged leaf throughout the year. A reddish appearance in dry leaf is undesirable if caused by coarse plucking. In this case the red appearance brought about by hard and coarse leaf is considerably emphasized by the presence of red stalk.

Make and Style:

This covers the general appearance of a grade. Here the expert decides whether the tea has a well-rolled and tightly twisted leaf as compared to open and flaky. Flaky tea also tends to infuse more quickly with the result that a second application of boiling water will produce inferior liquor compared to the liquor after similar treatment of a well rolled and twisted leaf. Although tip in itself has limited liquoring properties, it is nevertheless an excellent indication that the grade in question has been made from the finer shoots of the tea bush. Tip should be golden in colour and not pale, silvery or dull. Pale or silvery tip is caused by over withering and is usually accompanied by the thin liquors consistent with high withers. Dull tip is often seen in teas with a grey leaf appearance; in this instance tip has been damaged together with the leaf. Incorrect rolling will tend to damage tip and at the same time leave the leaf black in appearance. Should stalk and fibre be present, coarse plucking will be mainly responsible. Stalk in tea is most undesirable and liquors are generally inferior unless stalk and fibre have been produced by a very severe manufacturing treatment such as the C.T.C. process. In this case stalk and fibre are often unavoidable even with fairly succulent tea shoots. Stalk is merely the woody portion of the stem and is noticeable by its red appearance in a black tea. Fibre consists of shreds of stalk. Size of leaf is also a major point and the desirability of a grade being the correct size, large or small will depend on the buyer’s requirements.

Sorting

This should be regular, even and yield pieces of roughly equal size. A mixed tea containing a quantity of another grade, such as B.O.P. containing fannings, an O.P. containing dust etc., is most undesirable.

Nose

This is simply a matter of smelling the dry leaf and except for flavoury sorts is best done by burying the nose in the leaf, exhaling and smelling the aroma given off. The flavoury teas can be more fully appreciated by nosing without warming the leaf previously with the breath.

A considerable amount of information is obtained from nosing the dry leaf. Taints picked up during transit can be easily recognized together with manufacturing faults producing liquors, which are “burnt”, “smoky”, etc. A tea, which is old or out of condition can also be spotted at this stage.

Feel

This merely informs the expert whether and to what degree a tea is spongy, i.e. lacking density. It also ensures that a tea is not damp. If properly fired and preserved, a tea should be crisp to the touch when containing approximately 4% moisture. Teas with high moisture content deteriorate rapidly and are avoided by most buyers.

Decoction

About 2 gm of tea per 100 ml of water is weighed into porcelain pots provided with lids. Water, which has just reached boiling point, is then poured into the pots as quickly as possible. Speed is necessary at this stage to ensure that even the last tea for examination receives water, which is still boiling. Fresh water and water heated to the precise point of boiling is essential. Water, which is stale or has been over or under, boiled, will have a marked effect on the tea liquors. Water used for tasting should have its pH as close to 7 as possible and should not have dissolved impurities, metallic salts, in particular. After the water has been added the tea should be allowed to infuse for five or six minutes. As in all cases of comparison, conditions must be the same and it is of little consequence whether the tea is allowed to infuse for exactly five or six minutes or whether exactly 2 gm of tea is added to each pot provided the conditions are the same.

The requisite time having been given for infusing the leaf, the liquid is poured through a lid between the pot and lid into the tasting cup or bowl. The infused leaf, which remains behind, is placed in a recess in the pot lid. This recess is on the underside of the lid in order that the infused leaf may be visible to the Taster and lid is reversed on the pot with the recess and infused leaf uppermost. In this way the dry leaf, infused leaf, and liquor remain visible and within easy reach of the examiner. Any number of teas prepared from the same kettle of boiling water is called a batch.

Infused Leaf

During the examination of the infused leaf, the following need careful attention:

  • Colour
  • Nose.

Colour and appearance

The perfect colour of infused leaf is that of bright copper or red. Colour should be of an even shade throughout and all the leaves of approximately the same size. Although copper and red are the perfect colours, they are by no means a common feature but are generally reserved for tea produced during the quality period on estates in districts renowned for producing quality tea. It is, therefore, reasonably safe to assume that bright coppery or red infused leaf denotes quality liquor and with redness flavour may also be present. The following terms are used by Tasters to distinguish between degrees of variation:

  • Bright greenish
  • Mixed
  • Dull
  • Dark

Bright greenish: This usually implies that a tea has been under oxidised. Greenness is caused by leaf, which has failed to oxidised fully. Liquors obtained from a bright greenish infused leaf are generally quite brisk but to the point of possessing an unpleasant astringency or greenness. Colour and strength in cup may be lacking and quality will not be at its maximum; flavour on the other hand may not have been suffered.

During the Autumnal period hard green leaf may result in bright green infused leaf but in this case it is unavoidable and is to be expected.

Mixed: -This term is used when variation in colour between individual pieces of leaf is very marked. The term is usually coupled with another such as dull, and more especially green. Pieces of green leaf in infused leaf are simply portions, which have failed to oxidise and are usually caused by coarse plucking, low withers or inadequate rolling. Both coarse plucking and low withering affect rolling; instead of the leaves being twisted they are merely cracked and broken. In this way leaf cells are not ruptured and consequently oxidation does not begin. Daily variations in manufacture will also produce mixed infused leaf in the bulk. Liquor characters will depend on the adjectives accompanying the description “mixed” and may vary between extremes.

Dull: – Common plains teas manufactured during the monsoon period are often dull due to extremes of heat and the ideal conditions for bacterial development. Over oxidation is also responsible for this dull appearance. Liquors are generally coloury but are plain to the palate and completely devoid of quality. A little briskness may be present but never pungency.

Dark: – Dark infused leaf is brought about by badly burning the tea in the firing machines or by severe bacterial infection. In both cases the effect on the liquor is most unpleasant.

Some Tasters prefer to use the term “dull” to cover both the meaning of “dull” and “dark”.

Nose

This is the aroma obtained on smelling the wet infused leaf and is best tasted when the leaf is fairly hot. Delicate aromas as found in Darjeeling are clearly perceptible at this stage. Faulty manufacture causing fruity, burnt, smoky, sour liquors etc., can also be detected from the nose of the infused leaf together with any taints which are foreign to tea.

Liquor

The appreciation of tea liquor is determined by tasting. This is done by sucking in a quantity of liquid and air from a spoon or straight from the tasting cup. The liquid is allowed to roll on the palate while the air taken in with the tea is allowed to pass out slowly through the nose. If necessary, further quantities of air may be taken in through the mouth and ejected via the nose. In this way flavours of the tea become perceptible as well as tastes. Tea tasting is as much a matter of smell as of taste.

The liquid should be tasted at a comfortable temperature and with as much noise as will ensure the sucking of the tea well up on to the palate. After a few seconds the liquid is ejected into a mobile spittoon. During those seconds the tea has been tasted and most of the liquoring properties have been examined.

Milk added to dull liquors produces a grey and slatey colour effect. This dullness is generally linked up with bacterial infection during manufacture although damp and old teas will produce the same fault.

Colour

Depth of colour will vary between all grades from the same estate. Generally the smaller the grade the more coloury the liquor; in this way leaf grades are expected to have a lighter liquor than the Brokens, Brokens a lighter liquor than the Fannings, etc. Geographical location also plays an important part. Brightness is a very important factor. Tea liquors should never be dull to the eye and degree of brightness often corresponds closely to degree of quality. Common teas although possessing good depth of colour, are sometimes dull in appearance.

Quality

This is the essential characteristic of a good tea and is an impression derived from the palate when tea liquor is tasted. Although it is not possible to explain what quality in tea actually tastes like, it is possible to say that common, coarse and plain liquors are severely lacking in this quality.

Strength

This denotes substance in liquor and is generally described by a qualifying adjective such as “some”, “a little “or” good. Liquor colour is a good guide to strength; pale and light looking tea liquors generally have less strength than coloury liquors. This, however, should only be used as a rough guide as it is not uncommon to find coloury liquor, which is lacking in strength and a light looking liquor with good strength. Within grades from the same estate, strength normally follows colour and the colouriest grades, usually Dusts, are the strongest. Teas from North East India are renowned for their strength and this is most pronounced in Assam manufactured by the C.T.C. process.

Briskness

A live taste in tea liquor as opposed to flat or soft. Fresh spring water may possibly be described as being brisk when compared with cold boiled water. The taste is perceived from the gums and the under side of the tongue.

The extremes of briskness are pungent and soft. While certain districts are well known for producing pungent liquors, e.g., those in Assam and South Indian teas during the quality periods in particular, others produce tea with only a little briskness. The majority of these teas are manufactured during the monsoon period on low elevation estates. While it is not possible to produce pungent teas from all estates, it is nevertheless possible to produce soft liquor by faulty manufacture. This is generally linked up with extreme heating of the green leaf, bacterial infection, over oxidation or the packing of made tea with a high moisture content.

Briskness in tea liquor is a most desirable feature

Flavour

Flavour is a most apparent aroma, which is perceived through the mouth as distinct from via the nose. The most delicate flavours are found on estates at high elevations. Indian teas from Darjeeling and the Nilgiri Hills are renowned for their fine flavoury liquors. Other flavours which are not as delicate or “refined” may be found on high or low elevation estates in other parts of the world. The fineness of flavour produced from an estate will vary according to the time of year. For this reason the most valuable Darjeeling teas are manufactured during the Second Flush period.

The flavour of tea also varies from country to country and district to district. A Tea Taster for instance would have no difficulty in differentiating between the flavours of Darjeeling.

Manufacturing Faults

Faults in manufacture, which affect liquoring properties, are many and varied. Desirable liquor characters, such as quality, flavour, briskness, etc., may be completely lost due to faulty manufacture. Other manufacturing errors may leave a marked and most unpleasant taste in the tea liquors. Those most commonly encountered are caused by firing at incorrect temperatures producing either stewed or burnt liquors. The firing machine is also responsible for teas having a smoky taste in cup.

Bacterial infection during manufacture is far from uncommon and is borne out by the number of fruity and sour teas which is put up for sale in practically every auction. Bacteria are often the cause of much liquor failing which are far too frequently put down to other manufacturing errors.

Tea should be packed at maximum moisture content of 4 %. To pack with moisture content of less that 3 % would be uneconomical. Packing with more than 4 % moisture will affect the keeping properties of the tea and eventually result in liquors becoming tired, flat, mouldy, out of condition etc.

Taints

Tea in the green leaf stage as well as made tea is subject to picking up taints from any odoriferous source. The following taints and sources are the ones most frequently encountered in tea liquors.

Taints

Sources

Oil

Oil firing machines, line shafting or tea stored close to oil.

Chesty, Cedary

Immature or Odorous chest panels or battens.

Spicy, Peppery

Contamination with Chilly, Pepper etc.

Metallic

Unsuitable metal used in the green leaf stage, possibly during fermentation.

Papery

The wrapping of tea samples in unsuitable paper.

Chemicals

Pesticides, weedicides, etc.

Tea Cream

Clouding of tea is a result of the colloidal precipitate that is formed. This is called “tea cream”. Tea creaming takes place when black tea is cooled below 40OC. A weak complexation is formed between caffeine and polyphenols (theaflavins and thearubigins). The tendency to cream down varies from tea to tea. In black tea without milk, complexation and subsequent precipitation that occurs is negligible due to low (just 4%) caffeine.

In tea with a similar association takes place between the milk protein casein and various polyphenols. Due to the availability of casein in milk-tea the complexation is greater resulting in larger precipitation.

Tea Scum

Tea scum or the dark skin on the top of the brewed tea is the results of the high molecular weight component, which are, formed due to the influence of calcium and bicarbonate ions at the water interface. Very little scum is formed on a cup of very strong tea as the acidic tea polyphenols themselves partly neutralize the bicarbonate ions.

Lemon Tea

While lemon is added to liquor pH of the liquor is reduced and liquor becomes lighter and thin. At the reduced pH all of TF and also parts of TR are converted into anionic form, which imparts more bright and intense colour. This ionization also hinders protein complexation and therefore the briskness cannot be sensed on taste buds.