WO2002071855A1

WO2002071855A1 - Enzime inactivator for green tea processing

Info

Publication number: WO2002071855A1
Application number: PCT/IB2001/002252
Authority: WO
Inventors: Ananda Sarath Ranaweera
Original assignee: Ananda Sarath Ranaweera
Priority date: 2001-01-25
Filing date: 2001-11-23
Publication date: 2002-09-19

Abstract

Green tea has become very popular during the last few years because of its beneficial influence on human health. Special quality characteristics should be maintained in green teas in order to access a very competitivemarket. Extra value can be added to green teas when it is processed using organic green leaf. However, the prices of green tea fall down due to overproduvtion of green tea in tea producing countries. Therefore, cost of production should be reduced to offer green tea at lower prices to be in the international competition. As a solution, a new technique is introduced with a special enzyme inactivator for processing green tea. The green tea leaves are steamed in a blancher (3) with perforated steam tubes which are fixed to a vertical frame, standing parallel to another frame. The leaves are fed to the top of the apparatus and fall freely during the steam treatment. Cost of production in the new system can be reduced due to the application of the automated system.

Description

ENZYME INACTIVATOR FOR GREEN TEA PROCCESSING

TECHNICAL FIELD

The author carries out research and development work to invent more efficient systems for green tea processing. Author has a Patent No 10935 in Sri Lanka for discovery of special type of non-fermented tea. This abstract presents the invention or a special enzyme inactivator for green tea processing.

INTRODUCTION TO THE BACKGROUND ART

Green tea is processed using different inactivation techniques. Basically, the inactivation of enzyme is done by passing green tea leaves or withered tea leaves over a hot surface of metal or using wet steam. Once green tea is produced using two different blanching (enzyme inactivation) systems, characters of final green tea varies significantly depending on the types of enzyme inactivation and inherent characters of green leaf. Demand for green tea is also based on the liquor characteristics of the different type of green teas. Therefore, selection of appropriate blanching technique is important to cater the demanding consumer requirements. However, it is also important to select correct type of enzyme inactivator in order to suit the inherent leaf characteristics of the country or the area. Final selection of correct blanching technique should be done according to inherent green leaf characters, specially the content of ployphenols and amino acids and liquor charaαeristics of final products as well. Colour and strength of green tea liquor is influenced by the state of green leaf (fresh or wither) used for blanching.

Blanching is usually followed by different kinds of rolling and preliminary drying. Partially dried dhools (tea particles) are rolled again to make better shape and size of the dhool prior to the secondary drying. When secondary drying is not sufficient, another drying is carried out along with polishing or rolling. This also makes the final product more even and better looking. Dried tea leaf is graded to maintain the uniformity of the particle size and shape.

However there are many types of process techniques and grades and varieties of green tea available in the market.

Common types of green teas available in the world tea trade:

(1 ) Steam blanched:

• Sencha (most popular)

• Cyokuro (sun shaded)

• Kabusecha (semi sun shaded)

• Ten cha (sun shaded non rolled)

• Tamaryokucha

• Bancha (lower grade)

(2) Panning:

• Ureshinocha (comma-shaped)

• Aoyagicha (tinged with blue)

• Mee cha

• jian cha (Pining)

• Long Jing cha

Machinery to process green tea is very expensive. Therefore it is usually too risky to do research and development work on the acceptability of green leaf character for the green tea quality using the standard commercial green tea machinery.

In addition to the low cost of production, production of high quality green tea is required for better demand for green teas. It is important to maintain a sweeter character in green tea cup for the best price and demand. However, leaf from Sri Lankan, Indian and African origins has more polyphenols and less amino acids compared to those of Chinese and Japanese origins, resulting bitter character in tea liquor. This is very unfavourable in marketing of green teas in European countries. Use of a new blanching unit provides high pressure steam from perforated tubes fixed to paralleiy and vertically stand frame for inactivation of leaf with correct duration of inactivation of enzymes of freely fallen leaf from top to bottom which is beneficial to achieve the preferred character in green teas.

The new blancher and process technology leads to achieve sweeter character instead of bitter character which is caused by high polyphenol content in green leaf used for processing in the origins of Sri Lanka, India and Africa. Correct period and the blanching temperature of steam are the most important parameters to evaluate and maintain to achieve the best quality green tea. However, these parameters should be changed according to inherent leaf characters by carrying out research and development work on product development. The blancher is introduced after considering the aspeαs of controllable parameters to achieve the best results in any part of the world.

PROCESS

(1 ) Green Leaf colleαion

(2) Steam blanching

Newly designed blancher Refer Drawing 3 (attached)

(3) CTC rolling (3 times), refer the Drawings 1 & 2 (attached) * or orthodox type rolling

(4) Drying (in a conventional dryer)

(5) Secondary rolling

(required only for orthodox rolling)

(6) Final drying in a conventional dryer

(7) Grading (standard tea grading system) * Optional operation

(1 ) Green Leaf collection:

Any tender leaf is suitable for processing

(2) Steam blanching:

Newly designed steam blancher can be effeαively used to inaαivate enzyme before CTC rolling or any other maceration such as orthodox rolling.

(3) Rolling:

CTC or other type of roller can be adjusted to suit the requirement of grade percentage of the final produα. This should be planed according to the market requirement and the demand. Other types of rolling can also be carried out to produce leafy grades.

(4) 1 ^st Drying:

Any conventional dryer can be used to dry macerated dhools. Preferable moisture content of 3% should be maintained at the dryer end dhool samples of CTC green teas. Perforations below 2.2 are recommended for trays of ECP dryers or CTC type and 2.8 to 3.2 are recommended for leafy green tea types. For orthodox type leafy teas, one more drying is required.

(5) 2"* Rolling:

This is required only for orthodox rolled teas. After 1 ^st drying, partially dried dhools should be rolled again to achieve twist appearance.

(6) Final drying:

The same conventional dryer can be used to dry rolled dhools to the 396 final moisture level.

(7) Grading:

Standard grading machinery can be used effeαively to separate uniform size of tea particles. This should be done to satisfy the market or buyers requirement. OBIECΠVES

(1) To introduce Dust grade green teas to satisfy the demand of green tea bag requirement.

(2) To reduce the cost of production using new automated system.

(3) To accommodate high capacity of green leaf without any delay in batch arrangements.

(4) To introduce green tea with preferable liquor charaαeristics.

(5) To give option to seleα different type of rolling.

(6) To introduce sweeter tea irrespective of inherent charaαers and high polyphenol content.

BENEFITS

(1 ) Generate high revenue by value addition as foreign exchange.

(2) Save money by not importing standard green tea machinery for green tea processing.

(3) Low investment for processing green tea. CTC line or orthodox system available in a factory can be used for green tea processing after some modifications.

Claims

PATENT RIGHT CLAIMED FOR De-enzymer or Blancher: This new De-enzymer can be used to inaαivate enzymes of green leaf or withered leaf before maceration. The new De-enzymer shown in Drawing 3 consists of a motor driven leaf conveyor belt with leaf spreader, two anti direαional parallel steam spray units. Each unit consists of number of steam tubes with very small holes fixed parallel to each other on vertical frame. Both units are conneαed to a steam line separately. Leaf fed to the blancher by a motor driven conveyer form the top, treated by steam with pressure, falls to the bottom of the unit for colleαion (converized leaf colleαor fixed at the bottom). CLAIMED FOR: (A) De-enzymer

(1 ) Use of perforated steam tubes vertically or horizontally fixed to a frame which (one part or a unit) stands vertically and parallel to other unit in which steam sprays steam anti direαionally to inaαivate enzymes of leaf (refer Drawing 3).

(2) Use of this unit as single unit or more than one, smaller units separately in order to inaαivate enzymes of leaf freely fallen from top to bottom (refer Drawing 1 & 2).

(3) Use of this blaching unit combined with CTC or orthodox type maceration for green tea produαion.

OTHER CLAIMS:

Use of perforated steam tubes in other shapes such as oval, round, reαangle, square fixed on a frame, stands vertically to allow leaf falls from top to bottom automatically or leaf conveyed by vertical mechanically driven chamber. (B) Process technology

Use of this new blancher to inaαivate enzyme to process non or semi fermented teas along with process technology described in the article under process.

Products:

Use of BTl , BT2, BT3, Cha Broken (CB) and Cha Broken Special (CBsp) as whole names or part of any grade. These grades have been patented under the Patent of 10935 of same author in Sri Lanka.