1. Processing technology of tea Quang H. Luong, MSc. Department of Food Engineering Faculty of Food Science and Technology Nong Lam University – Ho Chi Minh City

2. 11-Aug-152 Course grading  Seminar: 30%  Midterm exam/Lab. Report/assignment: 20%  Final exam: 50%

3. 11-Aug-153 Contents - General introduction of tea - Flavonoids and other components of tea - Technology of tea products (Green, black, Oolong,…teas)

4. 11-Aug-154 History of tea  Reading of reference materials  Since 1690, E. Kaempfer named the bush “Thea” sinensis  In 1753, C. Linné named Camellia sinensis  Camellia sinensis (L.) O. Kuntze

5. 11-Aug-155 Countries grow tea plant

6. World tea market share in 2009 11-Aug-156 Courtesy: http://www.vietnam-tea.com/overview.html

7. 11-Aug-157 Tea growing areas of Vietnam Fig. 2 Vietnam and its location Hà Giang,Tuyên Quang, Cao Bằng, Lạng Sơn Vĩnh Phúc, Phú Thọ, Sơn La, Hòa Bình, Bắc Thái Nghệ An, Hà Tĩnh, Thanh Hóa Lâm Đồng, Gia Lai, Kon-tum

8. 11-Aug-158 Teas and health benefits  Tea as a panacea  Anti-carcinogenic activity Lung cancer, prostate cancer, breast cancer, skin cancer; stomach, pancreatic, oesophageal, and colon cancers  Anti-inflammatory and anti-microbial properties Dental and oral diseases AIDS  Cardioprotective and neuroprotective properties Heart disease Parkinson’s and Alzheimer’s diseases

9. 11-Aug-159 Flavonoids and other components in tea

10. 11-Aug-1510 O OHOH OHOH R1R1 OR2OR2 OHOH HOHO OHOH OHOH OHOH C O X = Forms of Catechin (-)-Catechin: R 1 = R 2 = H (-)-Gallocatechin: R 1 = OH, R 2 = H (-)-Catechin gallate: R 1 = H, R 2 = X (-)-Gallocatechin gallate: R 1 = OH, R 2 = X

11. 11-Aug-1511 O OHOH OHOH R1R1 OR2OR2 OHOH HOHO OHOH OHOH OHOH C O X = (-)-Epi form (-)-Epicatechin: R 1 = R 2 = H (-)-Epigallocatechin: R 1 = OH, R 2 = H (-)-Epicatechin gallate: R 1 = H, R 2 = X (-)-Epigallocatechin gallate: R 1 = OH, R 2 = X

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14. 11-Aug-1514 Technology of tea products

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16. 11-Aug-1516 Plucking Preservation Processing Core stages

17. 11-Aug-1517 Plucking of T-leaves and flushes Courtesy: http://tea-plucking.blogspot.com/

18. 11-Aug-1518 Categories of tea  Based on fermentation level Unfermented tea (Green tea) Full fermented tea (Black tea) Partly fermented tea (Oolong tea, Pouchong tea)  Based on tea-shape Loose, compressed form (tea brick), and powder teas  Based on processing-method Raw and scented teas

19. 11-Aug-1519 Courtesy: http://greentealovers.com/greenteatypeschina.htm

20. 11-Aug-1520 Courtesy: http://www.cookscorner.net/Tea/Antioxidants.html

21. 11-Aug-1521 Green tea processing Tea leaves and flushes Green tea productSteaming/Panning RollingPackaging ClassificationDrying

22. 11-Aug-1522 Oolong tea processing Tea leaves and flushes Oolong tea product Sunned withering Indoor witheringDrying Special rollingPanning Packaging

23. 11-Aug-1523 OTD - Black tea processing Tea leaves and flushesBlack tea products PackagingWithering RollingClassification DryingFermentation

24. 11-Aug-1524 Dried scented tea processing Tea panning (MC = 1.5 – 2%wb) Additive preparing (Drying, grinding) Blending (15 min.) Scented incubation (Temp. = 80 - 85 o C)

25. 11-Aug-1525 Tea blending with fresh flowers Tea Mixing Flower TurningScreening DryingNatural cooling Flower mixingFlower screening ‘Fresh flower scented tea’

26. 11-Aug-1526 Soluble powder tea processing Tea leaves and flushes Rolling/Grinding ExtractionDrying/steaming Aroma strippingFiltration Freeze dryingConcentration Spray dryingSoluble tea powder Packaging aroma

27. 11-Aug-1527 Tea extracts and their applications  Strong infusions Strong infusion are made by soaking tea leaves in alcohol/water mixtures (the catechin content is about 2% w/v)  Soft extracts Soft extract are made by concentrating the strong infusion to a water content of 20-25% (the catechin content is about 20% w/w)  Dry extracts Dry extract are made by spray drying the strong infusion after they have been concentrated to 40-50% solids (Catechin ~ 25% w/w)  Partly purified extracts  Purified catechins

28. 11-Aug-1528 Tea material Develop new T-products Study on bioactivity In vitro Study on animal Sample Blingding Commercial T-refine Products from T-catechins Study on human beings mechanism, toxic, digest, dose,… Trends in studying and developing new products from tea

29. 11-Aug-1529 T-preservation RH of air (%)3045606270808596 EMC of tea (%) 5,86,78,79,010,412,214,820,5 Table 1. Relationship between equilibrium MC of tea and RH of air

30. 11-Aug-1530 T-preservation Table 2. The effect of packaging vs. MC of tea Types of packaging MC of tea (%) 0After 30 days Glass flask with head-pin7,5 Tin box 7,5 Wrap by hands, 2 layers of paper7,512,8 Carton box with T-paper wrapping 7,513,8 Carton box with anti-humidity paper 7,512,7 Control (T without-package)7,514,0

31. 11-Aug-1531 T-packaging

32. 11-Aug-1532 End of lecture, continuing slides for reference

33. Free glutamate in foods 11-Aug-1533 Green tea

34. 11-Aug-1534 O OHOH OHOH H OHOH OHOH HOHO (-)-Catechin

35. 11-Aug-1535 O OHOH OHOH OHOH OHOH OHOH HOHO (-)-Gallocatechin

36. 11-Aug-1536 O OHOH OHOH H O OHOH HOHO OHOH OHOH OHOH C O (-)-Catechin gallate

37. 11-Aug-1537 O OHOH OHOH OHOH O OHOH HOHO OHOH OHOH OHOH C O (-)-Gallocatechin gallate

38. 11-Aug-1538 O OHOH OHOH R1R1 OR2OR2 OHOH HOHO OHOH OHOH OHOH C O X = Các dạng (-)-Catechin (-)-Catechin: R 1 = R 2 = H (-)-Gallocatechin: R 1 = OH, R 2 = H (-)-Catechin gallate: R 1 = H, R 2 = X (-)-Gallocatechin gallate: R 1 = OH, R 2 = X

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41. Aroma bamboo rotationer 11-Aug-1541

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48. Flavonoids in tea 11-Aug-1548 Green T.Black T

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50. 11-Aug-1550 Department of Food Engineering, FST, NLU