Regardless of tasters and methods of manufacture five biochemical factors, total oxygen uptake of unprocessed tea shoots and theaflavins (TF), thearubigins (TR), (-)-epigallocatechin gallate (EGCE) and theogallin (TG), of blackteaarethe main contributing factors of colour of North East India plains tea. Similarly, three constituents, TF, TR and (-)-epicatechin gallate (ECG) of black tea, are main the factors for brightness. Four factors, total oxygen uptake and ECG of unprocessed tea shoots and TF and moisture of black tea are the main contributing factors of strength of North East Indian plains tea.

An attempt has been made to determine, by using the miiltiple regression technique, the most importank biochemical constitirents affecting 'briskness ', 'quality' and 'cash valiration' and also

An attempt has been made, by using the multiple regression technique, to determine whether the term 'quality' of the North-East Indian plains black teas has its own single characteristic as recognisable by teatasters or if it is the integration of some of the other important liquor characteristics, viz., colour, strength, brightness and briskness, and to determine the influence of those liquor characteristics including quality on the 'cash valuations' of black teas.The multiple regression analyses showed that in general, regardless of tasters and methods of manufacture, quality of North-East Indian plains black tea was found to depend mainly on briskness, quality being increased with an increase in briskness.Cash valuations, both of crushing, tearing and curling (C.T.C.) and orthodox manufactured teas, in general, depended mainly on quality andlor briskness, cash valuation being increased with increase in quality and/or briskness.

No abstract