Innovations in Tea Processing Product diversification Value addition

Innovations in Tea Processing, Product diversification & Value addition Dr M T Ziyad Mohamed B Sc (Jaffna, SL), Ph D (Sheffield, UK) Director – Manufacture, Melstacorp (Pvt) Ltd. , Managing Agents for Balangoda Plantations Ltd. , & Madulsima Plantations Ltd. , E mail: ziyadthaha@yahoo. com; ziyad. teaconsult@gmail. com

75 Years of tea research by TRI of Sri Lanka Published in 2004 On cultivation as well as processing Only recent advances will be presented today. . .

Tea Industry in Sri Lanka Production – 300 mn kg (Orthodox – 92%; CTC – 7%; Green tea - 1%) Auction price – US $ 3. 23 /kg; FOB price - US $ 5. 05/kg!! CTC teas – no demand ? Green tea – not successful – unsuitable plant material? (plenty of research) Organic tea – not very successful (selection of fields – not appropriate!!) Huge potential for green tea and organic tea in EA

Success stories from orthodox manufacture In spite of low(est) field productivity, worker productivity and factory productivity (scale of operation) Tea sector, is doing well… Quality of tea! Attention to details by Tea Technologists

Innovations Selection of Cultivars for different types of manufacture Developed a rapid method using a domestic model microwave oven to screen cultivars suitable for green tea manufacture (very crucial) (Unpublished data)

Comparison of various kinds of Green Tea Polyphenols Amino acids (mg/g dry wt) Gyokuro (Japanese finest grade) 132 48 Sencha (Japanese popular grade) 229 21 258 18 Chinese green tea St Joachim Estate (Sri Lanka) 413 17

Innovations in processing - unit operation wise Withering In SL, 6’ width troughs – uniform withers - commonly used Critical Proper loosening of leaf, for air to travel through! -Wider (15’) troughs, - closed troughs, - reverse withering, - storage tanks - Are hardly used …. Capacity ? Average production 500, 000 kg/ annum ?

Judgment of wither is crucial: 1. Rapid method using domestic Microwave oven to check the moisture content in withered leaf, green leaf & made tea (Ziyad Mohamed et al. , 1998 & 2002)

2. Variable speed drives for trough fans Orthodox manufacture (Deranagama, …. . Ziyad Mohamed, 2002) 20% saving on electrical energy Saving to the country - US $ 4 million / annum 2 a) Development of a control system for withering (VSD) based on RH of the spent air (Boteju et al, 2017) Data acquisition system + Mathematical model

3. Controlling hygrometric differences …. For quality improvement, supply air with a Hygrometric difference Finding from VSD study -17% saving on electricity usage by controlling only the RH (4 – 60 F) Recommended electronic servo control units Did not catch up Furnace cum heat exchanger (air heaters)

KOSHYMA TEA WITHERING SOLUTIONS Recent introduction of technology - 4. Constant difference in dry and wet bulb temperatures- Factories using steam / hot water radiator systems (Murlidhar & Ziyad Mohamed - unpublished data). Withering using low dry bulb temperatures !! Uniform wither - quality improvement Energy saving No delays in manufacture – more crop ? Commercial installations in South India (Chundavurrai, Tenmalay, Haukal, …factories)

5. Experiments using load cells to judge withers – not successful ? (Load cell to cover only section of the trough ? )

Electronic sensors for monitoring Complaint. . Tea processing is an art ? Left to subjective judgment of factory staff !! 6. Introduction of electronics – not successful ! Research on computer aided tea processing ? ? (dust interfering with sensors) Parts of shoots harvested have varying moisture contents – not representative enough !! Sensors to monitor dry bulb and hygrometric differences ? (regular calibration? )

Rolling Sri Lanka produces the best orthodox tea! Reasons for Success – 6’ troughs and orthodox rollers, with “Kitul wood”!! . Optimum fermentation and best grade mix, if the leaf is rolled / twisted properly – Agricultural practices matter – twist High K – leaf may not be succulent and not amenable to twist (Personal observation from India)

Twist in the leaf is very crucial decides the grade mix. . Less publications on rolling - why ? ? ? Ø Leaf standard – varies quite a lot Ø Wither % - adjusted according to the leaf standard Ø Table fittings – “Kitul wood” – best friction better twist Ø Type of Batten - Brass or Kitul ? ? Crescent or M & S type; ‘A’, ‘B’ ‘C type Ø Type of Cone (Mild rettie, high rettie or steep rettie? ? ) Ø Charge (Quantity of withered leaf ) Ø Rolling time 30 mins, 20 mins or 15 mins Ø Pressure application Ø Speed of the roller ( 32 – 38 rpm ) Recommendations based on ground conditions ……

Rolling continued…. Single action roller – preferred…. Double action rollers are rejected ? Different batten & cone designs introduced

Research on alternatives to orthodox rollers Criticism - orthodox roller is “batch type” Extensive research on continuous machines ? ? Challenge is to twist the coarse leaf Only in a batch type roller – it is possible !! Sap from tender leaf, helps in twisting the coarse leaf Continuous rollers too were rejected ?

Orthodox – rotorvane manufacture After preconditioning, in orthodox rollers 8” rotorvanes - continuous machine (used in Up country) “Ceylon tea” lost it’s unique flavour characteristics ? ? Quantity too had been affected (3 gm 1. 5 gm per cup)

7. Computer model to select ideal rolling programs (Dahanayake, Jayasinghe & Ziyad Mohamed 2002) to achieve optimum rolling as well as optimum fermentation time for all dhools (fines) 1 st, 2 nd …… Optimum grade mix

Fermentation 8. Simple chloroform test, to assess the fermenting rates of different cultivars (Samaraweera & Ranaweera, 1988) Judgment of fermentation times and order of firing are crucial for ideal grade mix of teas. Do not waste your time, checking the temperature of the fermenting dhool !!

9. Simple Iodometric titration method (Ziyad Mohamed & Priyanthi, 1993) Orthodox as well as CTC manufacture Looking for colour codes ? ? 10. Identification of fermenting rates of latest cultivars (Ziyad Mohamed, 1998; Boteju……Ziyad Mohamed, 2011) Fast fermenting quality clones …. . 11. Thermodynamic properties of fermenting dhools – using modeling Moisture Desorption Isotherms (Boteju, Amaratunge, Ziyad Mohamed, 2012) Practical Applications……….

Drying / Firing Establishment of fuelwood plantations – major failure Especially after 1992 – Privatization of management of estates Recommended 20% of the extent, under fuelwood (1970 s !!) Not implemented ? ? Shortage of firewood ?

Drying / Firing 12. Renewed interest in Short Rotation Coppicing species (Gliricidia, Calliandra…) (Short harvesting intervals compared to 8 years and also provides additional nitrogen) Monocrop – marginal land Intercrop with tea

Research on Fuel efficiency 13. Gasification / 2 stage combustion – Failure C, H CO + H 2 CO 2 + H 2 O Co –generation of thermal and electrical energy Research - only for thermal applications ? ? Imported units and Local units - FAILED!!! Successful in other countries – Reasons - Continuous usage …. 1 month

14. Solar energy for tea drying Direct use is cheaper than storage system Solar energy could be used only for pre heating 25 – 600 C 60 – 1000 C or 1100 C using fuel Research findings indicate 17 – 25% saving (Koneswaramoorthy, Ziyad Mohamed, Galahitiyawa 2004) Huge capital investment ? ? ? Direct use / Sunlight (cloud cover) Night manufacture ?

Driers SL Pioneered Fluid Bed drying for tea – 1974 TRI – CCC Fluid Bed Drier (FBD) – Static bed Best for orthodox - rotorvane teas; Efficiency > 60%; Even firing Sine quo non for CTC manufacture Combination driers for orthodox leafy grade manufacture – Higher fuel efficiency - furnace design!! Not recommended for broken grade teas !!

Two stage drying In either conventional, FBD or combination driers, the enzymes PPO and Peroxidase, do not get completely deactivated affects the quality of tea, during storage (Ekanayake et al, 1987). Exposure to microwave irradiation, denature these enzymes irreversibly.

15. Drying using only microwave energy – Failure (Liyanage……. Ziyad Mohamed, 2004 a). Two stage drying - successful: 16. First stage - microwave energy and Second stage - conventional or FBD drier (Liyanage, … Ziyad Mohamed, 2004 b).

Grading Ideally - Grading followed by cleaning Not - Cleaning followed by grading ? Do not recommend installation of pickers on top of Trinnick If pickers are removing black tea ………? Should have a good idea about the grade mix produced Modify the existing machines - improve efficiency

18. Introduced a Single frame rotary sifter (SFRS) (Not a Trinnick) With Mesh sizes 24, 12, 10 & 8 Size of meshes …depending on the grade mix Chota sifters – varying lengths of trays – Why? ? Mesh sizes No 10, 12, 16, 24 & 30

3 in 1 machine - work of fibromat, Myddleton, Chota Fibromat connected to the drier discharge

Myddleton Sifters Top tray – jumbo pickers Bottom tray - two meshes No 30, 24 / 20 Fibromat installed with No 40 mesh ? ? (Extracted Dust, Dust 1, BOPF)

East Africa… Best CTC teas But fine tuning is very much possible BEST is the enemy of GREAT !!! Clue – How much is crushed / recycled after firing > 3% ? ? CFUs may not be working properly! (Quality? ) Drying is wrong! Sifting is wrong!

Potential for product diversification Evaluation: a) Product/s identification. b) Market survey – Demand? c) Technical feasibility / R & D. d) Financial feasibility/ Profitability – Huge capital investment may be needed.

Identification of products for diversification i. Different types of tea. ii. Different forms of tea - Loose tea, tea bags, scented tea, iced tea, instant tea, RTD tea… iii. Tea based products - cosmetics, pharmaceuticals, sweets, neutraceutical, dishes, Tea Wine etc. iv. Products derived from tea - extractions – anti-oxidants, flavour compounds, amino acids, caffeine, Theanine

Different types of tea Organic (Bio) tea or Conventional Green tea or Black tea Green tea (Japanese or Chinese type) Black tea (CTC, LTP, Orthodox/rotorvane) Oolong tea White tea / Purple tea Pu-erh tea Brick tea Herbal tea – with and without tea ? ?

Health Claim - Black Tea or Green Tea is better? Black Tea as well as Green tea will have good demand China diversifying into black tea !!! (Caution: Shift from Antioxidant Pro-oxidant) PROCESS? ?

Japanese type or Chinese type in EA? Same raw material, similar unit operations Final product/s? Optimize unit operations careful evaluation (Grade mix) Machinery should be adapted, to suit local conditions (Panners, rollers, Sifting machinery etc. , ) Role of Tea Technologist is vital !!!

Relationship with jat and chemical composition At higher elevations in East Africa Potential for good quality Green tea, provided appropriate cultivars are identified through chemical analysis or microwave oven method Additional demand due to, less use of pesticides…. .

Sri Lankan experience with green tea – (for comparison)… Green tea was not successful … only 1 – 2 % of the total production Issue: Raw material is not right…. large leaf (assamica) varieties

4. Black Tea: Pure orthodox type – appearance and liquors; Orthodox – rotorvane type strength and flavour (compromise!!)

Pure orthodox – East Africa vis-a-vis Sri Lanka Low elevations - preferred High elevations – less maceration, fermentation? ? Technical – OK, Financial – OK, Logistics………. high crop….

Constrains/bottlenecks: I. Jat – large leaf preferred – more polyphenols more colour ii. High Elevation – Low temperature - Chemical composition? Less succulent “filler teas” Fermentation may not be complete – low temperatures ? iii. Automation is difficult - More labour is needed… iv. Need Conventional/Combination driers – lower outputs !! v. Major Bottle neck - Grading – too cumbersome – Number of grades 18 - 20 Michie sifters, with very low outputs are widely used

More staff, more workers with skills required (vis- a - vis CTC ) Cost of manufacture – will be easily about US $ 0. 2/kg more? Apart from capital cost on expensive colour separators, a) Labour output of 30 kg Vs 80 kg for CTC b) Electricity – 1. 3 kg/k. Wh Vs 2 kg/k. WH C) Packing density / cost – 35 Vs 55 kg in a bag (Need Rigid T sacks / Container sacks) d) High Transport cost – 7 tons Vs 11 tons in a 20’ container Land locked countries (except Kenya/Tanzania)

Leaf Quality requirements for leafy grade teas are: blackness, twist and the coloury liquors Technically feasible Quality to match Ceylon teas ? ? (Eg: Vietnam teas) Large leaf preferred …. Logistics may be difficult. Option - to produce part of the quantity (10 – 20%)

Orthodox / Orthodox- Rotorvane : EA teas will not match Ceylon tea – high grown? ? Climatic conditions are too conducive for growth ? ? 1. SCALE OF OPERATION? Batch process– space consideration 2. Withering - Withers (55% - 58 % moisture) – feasible? 3. Rolling - Orthodox rollers still used for pre-conditioning Why? 4. Roll Breaking – Dhool extraction after each Rotorvane cut – using sifters (roll breakers)

4. Fermentation - CFUs ca be used adequate space for fermentation (3 hr) of each dhool separately (LABOUR) 5. Firing: Firing order of dhools needs changing – batch to batch (human error) … VP Vs Seedling tea 6. Drying: FBDs are better than conventional driers. TRI – CCC FBD is the best (SL Experience) – Capital cost 7. Higher COP –cost of labour, electricity, packing, transport

New blender designs or manual blending (Capacity)? ? ? Factory floor …teas lying all over – more space needed!! Stock holding is high – 6 -10 days stock held cash flow issues? ? Time taken from bush to cash? ? ? Shipping cost is high……. Handling: Particle breakage !!! Auction/Brokerage – More number of lots – logistics ? ? ? Huge ware houses are needed!!!! Look at the bottom line !!!

Benefits of Value addition SRI LANKA (FOB Prices) % SL Rs/kg Tea In Bulk 41 495. 86 3. 82 Tea In Packets 49 519. 77 4. 00 Tea In Bags 7 1, 078 8. 29 Instant Tea 1 884. 64 6. 81 Green Tea 2 1, 171. 81 9. 02 100 563. 94 4. 34 TOTAL US $/kg Auction Average – US $ 3. 23 per kg Export earnings – US $ 1. 5 billion

5. i. Value Addition added tea: Tea bags … Good demand, price & quality are issues ii. Scented (flavoured) tea– Mint, Earl Grey, Cardomom (natural) Technology is simple, bulk tea is scented by importers/sellers iii. Carbonated or Ready to drink (RTD) tea – in many flavours Tea content < 1% of the SS; “DE-CREAMING” - necessary? iv. Iced tea – Demand in USA, Canada. Technology is simple, Loose tea, instant tea or tea bag is used by importers Ceylon tea is preferred – liquor colour and less creaming !!! v. Instant tea – flavor is lost … more colour in your liquor

Different types of tea bags available in the shelf Double Chamber Pyramid type

6. Strategy: Creating market opportunities Strategies to penetrate tea bag market – international, regional or local? International tea bag market is somewhat saturated! Analyze the value chain – it will be difficult to penetrate into the bottom end Improve quality of tea and aim at niche market

7. Products incorporating tea as a component i. pharmaceuticals, ii. neutraceuticals, iii. cosmetics etc. , iv. sweets (toffee, ice cream, cakes, yoghurt) v. tea cider or tea wine (TRI SL has a patent) vi. Dishes – soup, seafood, salad, smoked duck…. . (China) Promotion through Health benefits of tea. Market survey and promotion are needed!!

a) Seafood steamed with Chinese tea b) Chicken served with Pu-erh tea c) Oolong tea served with shrimps

Tea Sweets Tea Chocolate Tea yoghurt Tea Toothpaste

Extractions i. Flavour – a lucrative business – in the West/Japan/Far East (Eg: Seasonal teas from SL used for flavour and catechins) ii. Catechins and polyphenols as antioxidants, iii. Caffeine – stimulant … used in energy drinks iv. Theanine – medicinal properties – mental relaxation v. Dyes …. . vi. Others - tea seed oil vii. Proteins as animal feed from waste tea. Technology available Market + Cost / benefit?

Presenting tea in different packaging … SL pioneered packing Pure Ceylon tea in; i. Ceramic containers, ii. Handicraft pouches, iii. Coconut (whole) shells etc. , Value addition for tea as well as the packing material…

Product diversification would require, funds for a) R &D –– Strengthen R & D at Research Institutes & Universities b) Market research - expensive c) Subsidy for value addition machinery and factory modernization d) Strengthen training facilities Sri Lankan success – un-interrupted cess funds (Upto 2000) - generated by the industry and channeled right back to the industry, without going to the treasury - for above purposes Eg: i. CTC – 85% of capital cost - through subsidy (1990’s) ii. > 75% for tea bagging machinery…. iii. 33% subsidy for most orthodox machinery

Thank you very much for your attention