Grades

Despite more or less intense sifting, bulk obtained after drying are still heterogeneous. Tea ranges in size from that of a speck of dust to a leaf approximately 4 cm long and 1cm wide. The fractions are to be brought to the desired sizes and forms with adequate uniformity and cleanliness conforming to trade requirement. Tea is, therefore, sorted into pieces of roughly equal size. Four main sizes are produced, namely, Whole Leaf Grades, Brokens, Fannings and Dusts. Within each of these sections tea is further split up into grades of varying qualities. Whole Leaf Grades are the largest sizes produced and depending on the actual grade within the section may range from a long and wiry stem, 1cm to 2cm in length, to a round and knobby twisted leaf similar in size and shape to that of a small garden pea. Of the former style there are the Orange Pekoes and long Leafed Pekoes.

Broken grades consist of smaller than the Whole Leaf Grades, are generally about 1cm in length and are largely made up of leaf as opposed to stem. In this section are the Broken Orange Pekoes, Broken Pekoes, Broken Pekoe Souchongs and the Broken Teas. Fannings Grades are smaller still and sizes of more than 1/8 of an inch are rare. Fannings contain small parts of the leaf, which have broken off either during rolling or sorting and consist mainly of Broken Orange Pekoe Fannings, Orange Fannings, Pekoe Fannings and Fannings.

Dust grades are self-explanatory regarding size and are generally made up of the Pekoe Dusts, Dusts and Churamoni Dusts.

Within the Trade grades are abbreviated by using the first letter only of each word. In this sense a Broken Orange Pekoe becomes a B.O.P., an Orange Fannings becomes an O.F., etc.

The Grades and sub-grades are as follows:

Various machines sort out all grades

Sorting

The guideline for sorting orthodox and CTC tea sorting is given below:

1. Orthodox tea

The bulk mal initially is passed through a Myddelton Stalk Extractor. The Myddelton's are fitted with trays of either 17/64/0.125" and or 3/16/0.125". The top and bottom trays of Myddelton should be so adjusted that only broken grades are removed. These feed directly into the sorter conveniently sited near the Myddelton. The bottom tray of the Myddelton should contain mainly whole leaf grades and these should feed into wire mess googie having No. 12, 10, 8, and 6 meshes. Through No.12 FTGFOP, No.10 TGFOP, No.8 GFOP and No.6 FOF grades will be obtained. The spill from the googie will go to the breaker cum stalk separator machine. From breaker the mal will go to a Myddelton. From the top tray of Myddelton the mal will go to pucca sorter and following broken grades will be obvtained. From the bottom tray of Myddelton the smaller grades will be obtained through another pucca sorter.

2. CTC Tea

The following sorting process is now-a-days very much popular. The CTC bulk mal is passed through a fibre extractor and a pre-sorted. From the pre-sorted the larger leaf will go to a sorting machine from where the broken grades are obtained. Medium size particles will go to another sorting machine to give fannings. Likewise the smaller particles will go to a third sorting machine from where dust grades will be obtained. The following diagram will show the process.

Tocklai Tea Breaker

Breakers are used to reduce the particle size of orthodox tea. These breakers use the principle of crushing, which, if not used judiciously, may lead to greying of tea. Besides, picking of stalks has to be done manually and is thus a labour intensive process.

Unlike these breakers, the breaker developed at Tocklai, known as the Tocklai Tea Breaker (TTB), has a unique action. In this unit, the tea is passed on to a Roller running at high speed. The roller, which is fitted with rods throws the tea on a stainless steel striker plates at a certain force (action is like throwing the tea against a wall). Tea being brittle, breaks but the stalk does not. The striker plates deflect the tea back on the roller, which in turn, throws it back again on the next lot of striker plates. Thereafter the tea passes on to the second roller for repeat operation.

Since no crushing is involved, a) the tea retains its bloom, b) mostly leaf and broken grades are produced and c) most of the stalk remains intact.

The tea, after breaking, is passed through a Middleton or a Sorter, during which approximately 50% of the tea is recovered as leaf and broken grades. The balance coarse tea is again passed through the TTB and the Sorter. The process is repeated till the final coarse mal consist mostly of stalk.

Packing

After the tea has been manufactured and sorted into its respective grades, it is necessary to pack it in suitable containers so that, its quality does not deteriorate. Bulpacking containers should be fed from a hopper at a regular rate or fed and the containers should be filled expeditiously. Tea should never be forced down by hand to save the same from loss of bloom, damage and dust. The CTC teas made from underwithered teas are likely to be damaged more, unless handled carefully.

The moisture content of the made tea and its shelf-life are closely related. Maximum amount of tea should be packed in the container because oxygen and moisture in the free space promotes bacterial growth and enzymes are regenerated affecting the TFs in particular. After filling, the containers should be closed promptly.

Tea should contain no more than 4% moisture ,when it is packed preferably 3%. There is no harm in bringing the moisture content down to say 2.5%, but no extra benefit will result. Furthermore reducing moisture much below 3% is a costly operation, as the rate of loss of moisture becomes very slow at that low moisture content.

Teas made from day to day vary both in leaf and liquor. Hence before packing into chests it becomes necessary to bulk all the leaf intended to be sent in one break to ensure uniform leaf and liquor in each container. Tea of the grade are tipped on to a canvas sheet, spread on the floor of the packing room in a circle and then shovelled into the centre of the canvas. During the process of sorting and bulking, tea picks up moisture and more often than not the moisture content is much above 4%. It is therefore necessary to final fire the tea in order to bring down the moisture content to about 3%. This final firing is known as `gapping'.

Opinions differ about the desirability of gapping. Some believe that gapping has a detrimental effect on the quality of tea and say that it is desirable not to gap the tea before packing, provided the moisture content of the tea is not more than 4.5%. It is true that gapping has a slightly detrimental effect on the quality of the tea, but it is likely that quality will be preserved over a longer period if the tea is gapped.

Sampling should be done in such a way that it is representative of the whole bulk of tea from which it has been taken. If the sample is taken from the top layer of the heap then it is quite likely that the percentage moisture in the sample will be more than in the bulk of the tea due to the absorption of moisture on the surface from the atmosphere. Similarly if the sample is drawn from the bottom layer of the heap lying on a damp floor, then the leaf, which is liable to contain more dust and small broken leaf, will have high moisture content. A correct and representative sample should be drawn from different places in the heap. The container used should be clean and air tight. A sample should not be pressed in a container as the leaf is liable to be broken while under pressure. Samples, it should be collected with hands clean and free from any odour. Hair oil taint is very common in tea samples. If the container is an aluminium one the joint should be sealed completely with cellotape. If the container is made of plastic, the lid should be screwed firmly. If the plastic container is overfilled it becomes difficult to fix the lid firmly. Labels with full details including date of manufacture and name of estate should be pasted on top of the containers for identification.

Bulk packing containers should be fed from a hopper at a regular rate or feed and the containers should be filled expeditiously.