Specialized english in food technology

251 39 0
Specialized english in food technology

Đang tải... (xem toàn văn)

Tài liệu hạn chế xem trước, để xem đầy đủ mời bạn chọn Tải xuống

Thông tin tài liệu

NHA TRANG UNIVERSITY Faculty of Food Technology Specialized English in Food Technology Van Tang Nguyen, PhD September 2019 Contents  Introduction to subject  Basic concepts and definitions  Special topics in food technology Special topics in food technology Tropical products: tea, coffee, cocoa, cashew and pepper Fruits and vegetables Fermented products: wine, beer, beverages and other foods Milk and milk-originated products Canned foods Food oils and fats Cane sugar Bakery and confectionary Functional foods 10 Food safety 11 Machines and equipments in food processing 12 New trends in food science and technology Assessment Attendance/attitude: 10% Exercise(s) (40%): Class exercises, home works and student’s presentations Final exam (50%): Reading and writing References [1] International Food Information Service 2009 Dictionary of Food Science and Technology (second edition) Wiley-Blackwell [2] Bùi Đức Hợi cộng Từ điển công nghiệp thực phẩm Anh Việt NXB Khoa học Kỹ thuật [3] Nguyễn Thị Hiền (Chủ biên) 1998 The language of chemistry, food and biological technology in English Trường ĐHBKHN [4] Nguyen, V T (Ed) 2017 Recovering bioactive compounds from agricultural wastes John Wiley & Son, UK & USA [5] Other references suggest by lecturer: Books, articles, websites,… Author's personal copy Tea, Coffee, and Cocoa L Diby, J Kahia, and C Kouame´, World Agroforestry Centre (ICRAF), Abidjan, Ivory Coast E Aynekulu, World Agroforestry Centre (ICRAF), Nairobi, Kenya Ó 2017 Elsevier Ltd All rights reserved Introduction Tea, coffee, and cocoa are cultivated for their young leaves, cherries, and beans, respectively, from which popular beverages are made and consumed worldwide In addition to being used as beverage, cocoa is essentially consumed as chocolate confectionery products The stimulant properties and medicinal values of these beverages are recognized since the ancient times These crops are among the most important agricultural commodities worldwide Tea is the most popular beverage, and it is consumed by 65% of the world’s population, while coffee ranks second with about billion cups consumed daily Nearly kg cocoa bean equivalent is consumed per capita annually in developed countries In 2012, the production of processed tea, green coffee, and cocoa beans was 4.8, 8.8, and 5.0 million MT, respectively This production occurs largely in the developing world (with the exception of tea in China), while the consumption happens mainly in the developed economies For each of these commodities, more than 50% of the production is in only three countries, but unlike other products such as crude oil the market price is regulated by consumption countries The economy of many growing countries depends heavily on the earnings from these crops which support directly or indirectly millions of people in both producing and consuming countries Tea, coffee, and cocoa originated from Asia, Africa, and South America regions, respectively They have been domesticated over time and selected for different production environment and constraints Currently, the production takes place essentially within 20 N and 20 S of the equator in different climate conditions (Figure 1) They are perennial trees or shrub crops that can remain economically viable on the same land for 30–50 years after planting for cocoa and coffee, and more than 100 years for tea The production system is extensive and dominated by smallholder farms It is also characterized by the monocropping practices that raise some environmental concerns The yields are very variable worldwide due to different environment conditions and management practices This article is a summary of basic knowledge on the origin and ecology, the growth and development, the different propagation methods, and the management practices for each of these crops dry winter in the other hand Tea was discovered in China about 5000 years ago, and it was first consumed as medicinal drink and later on as a beverage Its consumption became popular in the seventeenth century when British settlers introduced it in India Currently, tea is produced in more than 50 countries in the world It belongs to the family Camelliaceae and to the genus Camellia which accounts for more than 200 species Cultivated tea plants are hybrids of C sinensis and C assamica In its natural habit, C sinensis is an evergreen shrub of 1–2 m tall with hard, thick, and leathery leaf C assamica is a small tree of 10–15 m tall with broadly elliptic leaf blade of 8–20 cm long and 3.5–7.5 cm wide C sinensis is diploid (2n ¼ 2x ¼ 30) while C assamica is triploid (2n ¼ 3x ¼ 45) Ecology Tea is adapted to a wide range of growing conditions including altitudes ranging from sea level to about 2800 m a.s.l and temperatures varying from À12 to 40  C while optimal temperature ranges from 18 to 20  C C sinensis is more tolerant to high altitude and low temperature, while hot and humid climate are more suitable for C assamica The rainfall range is between 900 and 6000 mm, while optimal rainfall uniformly distributed over the year is about 1600 mm The ideal relative humidity is within 70–90% The best soil should be porous, well drained, with pH of 4.5–5.5 although tea can accommodate pH between 3.3 and Growth and Development Shoot growth and development are the main component of yield in tea Shoot growth is characterized by three chronological stages starting with a slow enlargement of the axillary bud and the release and development of the leaf primordial This stage is followed by leaf unfolding during which shoots extend and the leaves develop During this second stage, the number of shoots increases with soil fertility level, and each shoot harvested replaced itself by 1.1–1.6 new shoots The third stage corresponds to the dormancy of the terminal bud The duration of the first two stages is variety and environment specific The flowers are generally white, occasionally with pale pink pigmentation and are borne singly or in pairs in the cataphyllary axils Tea crops begin to fruit 5–6 years after planting, and each fruit contained two to three seeds Tea Historic and Botany Propagation Tea (Camellia sinensis (L.) O Kuntze) is believed to have originated from the high regions of Southwest China, Myanmar, and Northeast India These areas are characterized by monsoon climates with warm and wet summer in one hand and cool and Tea is propagated mainly through cuttings and seeds Cuttings are harvested from healthy vigorous growing plants that have not been pruned for 4–9 months, and usually the middle portion is preferred Each cutting is about 3–5 cm long with 420 Encyclopedia of Applied Plant Sciences, 2nd edition, Volume http://dx.doi.org/10.1016/B978-0-12-394807-6.00179-9 Encyclopedia of Applied Plant Sciences, Second Edition, 2017, 420–425 Author's personal copy Tropical Agriculture j Tea, Coffee, and Cocoa Figure a) Tea, b) coffee, and c) cocoa production countries in the world (FAO, 2012) Encyclopedia of Applied Plant Sciences, Second Edition, 2017, 420–425 421 Author's personal copy 422 Figure Tropical Agriculture j Tea, Coffee, and Cocoa (continued) one healthy leaf The best period to collect and keep them fresh is on cool and cloudy day The cuttings are planted straight or slightly slanted so that the leaf does not touch the soil They are then transplanted to the field about 12 months later once they are rooted Seeds are planted at a depth of 1.5–2.5 cm, with the ‘eye’ of the seed pointing downward They sprout within one or several months after planting Crop Improvement and Management The initial work of tea breeding focused on yield improvement However, the lack of information on the defense mechanism and stress tolerance has prevented progress on selection for pest- and disease-resistant cultivars Tea production is constrained by more than 100 fungal diseases, among which Camellia dieback and canker are the most serious and are caused by Glomerella cingulata Camellia flower blight caused by Ciborinia camelliae is another serious fungal disease A number of viral, bacterial, nematode, and numerous pests also pose major production challenges To mitigate these challenges, an integrated pest management (IPM) approach is recommended N is the key mineral nutrient for tea being a leaf crop Tea is sensitive to the source of N with ammonium source promoting growth and development while the nitrate source inhibits growth Sulfur and trace elements like Zn, B, and Mo can be applied on needed basis Pruning is one of the most important operations, next to plucking, which directly determines the productivity of tea It prevents top growth and stimulates growth of the bush for comfortable plucking with renewed and vigorous branching pattern It is important to establish a well-developed primary frame and branch system to ensure a complete ground cover as early as possible Coffee History and Botany All commercial coffee species originated from Africa and belong to the genus Coffea The high-quality C arabica originated from the rain forests in the southwestern highlands of Ethiopia C canephora varieties including robusta coffee, grow at lower altitude and perform well in the equatorial, warm, and wet tropics, and they occur naturally in the western Congo basin There exist also two additional minor coffee species, C liberica and C excelsa that are genetically considered as a single complex C liberica originates from West Africa around Liberia while C excelsa comes from the drier parts of Central Africa, mainly Central African Republic Coffee belongs to the family Rubiaceae, which has about 500 genera and more than 6000 species The genus Coffea L comprises more than 100 species, of which only two (C arabica and C canephora) are commercially cultivated C liberica is also cultivated in Encyclopedia of Applied Plant Sciences, Second Edition, 2017, 420–425 Author's personal copy Tropical Agriculture j Tea, Coffee, and Cocoa 423 a small scale to satisfy local consumption Almost all the coffee species are diploid (2n ¼ 2x ¼ 22) and generally selfincompatible except C arabica which is a natural allotetraploid (2n ¼ 4x ¼ 44) self-fertile species at 15 C Tissue culture is used to rapidly multiply elite hybrids and clones Coffee plants can be regenerated using three general procedures, namely, axillary bud branching, shoot organogenesis, and somatic embryogenesis (SE) Ecology Crop Improvement and Management Coffee can be cultivated from a few meters to up to 2000 m a.s.l., although higher altitudes generally produce a better quality crop Temperature is one of the limiting factors for coffee and the optimum range is between 15 C and 24 C Rainfall is the second most important growth limiting factor with range between 1000 and 2000 mm However, in lower rainfall areas, irrigation is a common practice The best soil should be well drained, deep, and rich in organic matter with pH range from 5.4 to 6.0 Coffee breeding is largely restricted to the two species, C arabica and C canephora, that dominate world coffee production However, C liberica has contributed useful characters to the gene pool of C arabica and C canephora through natural and artificial interspecific hybridization Initial breeding objectives were to increase productivity and adaptability to local conditions The appearance of coffee leaf rust (Hemileia vastatrix Berk and Br) in epidemic scale in Southeast Asia between 1870 and 1900 changed the breeding focus worldwide with focus on disease resistance Although conventional breeding is mainly used for coffee improvement, it is a long process involving selection, hybridization, and progeny evaluation In recent years, the coffee genome has been sequenced using highthroughput technology and this has substantially shortened the breeding process Coffee grows well under shade, and naturally occurring varieties can only be cultivated under shade trees as it was practiced in the earlier years However, the release of new full-sun hybrids with high yields circumvented the use of shade resulting in quality depreciation, loss of biodiversity, and other environmental changes Major coffee pests and diseases are outlined in Table The recommended disease management options include the use of tolerant varieties, chemical and biological control as well as best cultural practices Coffee berries removed proportionally more nutrients compared to the harvested products of cocoa and tea K and N are the major nutrients required in coffee production K contributes to fruit development while N is necessary for vegetative growth P uptake is less important, but it is essential for root, flower, and fruit growth and development Other nutrients such as B and Zn are applied on needed basis For optimal growth and productivity of coffee, the trees need to be pruned Pruning helps to establish a strong framework, maintain the ideal crop leaf ratio and rejuvenate the tree There are basically two pruning systems, namely single Growth and Development The growth and development in coffee is divided into vegetative and reproductive phases There are two distinct structures in this phase, the root and the shoot systems The root system is composed of the vertical and lateral roots that grow parallel to the ground and the tap root that grows vertically down the ground The density and length of roots of most important species are age dependent and vary with the planting densities, soil characteristics, and cultural practices The shoot system has two main components, a main vertical trunk (orthotropic) and primary, secondary, and tertiary horizontal branches (plagiotropic) This phase includes flowering, fruit development, and ripening Three to four years after planting, flowers grow in clusters in the axils of the coffee leaves After fertilization, the subsequent fruit development is organized in five stages: (1) pinhead that spreads from to 10 weeks after blossoming, (2) rapid swelling that takes place from 10 to 17 weeks, (3) suspended and slow growth that lasts about weeks after the rapid swelling stage, (4) endosperm filling occurring 19–28 weeks, and (5) ripening stage that extends from to 12 months after flowering Propagation Coffee is propagated through seeds, cuttings, grafting, and tissue culture For cuttings, the non-lignified orthotropic shoots with one node are harvested early in the morning when the relative humidity is comparatively high The cuttings are kept in propagator for rooting and then potted in nursery containers filled with compost for 2–3 months before replanting in the farms Grafting has been used to graft C arabica species (which have a root system susceptible to nematodes) on C liberica (which is resistant) The best grafting methods are simple cleft grafting, top grafting, side grafting, and shield grafting that are used to propagate natural hybrids and clones With seeds, in order to reduce the risk of cross pollination, fully ripened berries from trees growing in the center of a block are used They are harvested, pulped, and dried for immediate germination on sand bed before transplanting them in polybags containing appropriate substrate For conservation, the seeds are further dried to a moisture content of about 41% and can be kept viable for more than years in airtight polythene bags Table Major coffee pests and diseases, causal agents, and prevailing areas Pests and diseases Causal agents Prevailing areas Coffee leaf rust (fungus) Coffee berry disease (fungus) Stem borers (insect) Hemileia vastatrix Africa, Asia Colletotrichum kahawae Coleoptera: Cerambycidae Pseudomonas syringae Hypothenemus hampei Leucoptera coffeella Africa, Asia, and South America Africa, Asia, and South America Africa Bacterial blight (bacteria) Coffee berry borer (insect) Coffee leaf miner (insect) Encyclopedia of Applied Plant Sciences, Second Edition, 2017, 420–425 Africa, South and Central America All production areas Author's personal copy 424 Tropical Agriculture j Tea, Coffee, and Cocoa stem (single trunk) and double stem (multiple trunk) The fundamental difference is the number of stems and branches maintained on the trees of fruit and seed maturity Growth stages and last 150–200 days after anthesis The last growth phase (growth stage 9) is the senescence Propagation Cocoa History and Botany Cocoa (Theobroma cacao L.) is native to South (Amazon forest) and Central Americas It has been known and cultivated by the Mayas and the Atzeques for about 2000 years The crop was first moved from its area of origin and expanded throughout Mexico by the Atzeques While the Spanish settlers discovered the crop in the Caribbean in the sixteenth century, cocoa was cultivated as cash crop only in the seventeenth century It was introduced in West Africa through Sao Tome and Principe in 1822 by the Portuguese settlers The genus Theobroma belongs to the order Malvales and to the family Malvaceae (previously Sterculiaceae) Theobroma includes 22 species of which only T cacao and T grandiflorum have economic values with T cacao being by far the most important of the two T cacao is both self-incompatible and self-compatible depending on the genotypes, and it is diploid (2n ¼ 20) Ecology Cocoa is an evergreen understory tree with a height of up to ca 9–10 m in its natural habit, although cultivated cocoa are managed at a shorter height While cacao can grow under temperature varying from 20 to 30  C, the optimum growth occurs under 25–28  C The ideal rainfall range varies from 1500 to 3000 mm, which should be well distributed throughout the year with less than months of dry season Relative humidity is a major limiting factor in cocoa production and RH above 80% is required Cocoa can grow on a variety of soil types; however, the best soil should be deep, light with sufficient organic matter and pH varying between 5.5 and Cocoa is mainly propagated by generative and vegetative methods With the generative method, cocoa seeds are directly sown in the field or raised in nurseries for about months before transplanting in the field It is recommended that seeds are produced from known parentage to limit genetic variation in the progenies The vegetative propagation is suitable for genetically heterogenous planting materials It includes mainly cuttings, grafting, and SE Cuttings are collected from young fan branches or orthotropic shoots and are rooted in potting substrates before transplanting them on farms Grafting consists of using scions from elite cocoa plant materials and grafting them on young cocoa seedlings or mature trees, referred to as rootstocks (Figure 2) SE is a tissue culture cloning method that uses plant parts (immature flowers for cocoa) to regenerate plantlets Crop Improvement and Management Cocoa breeding work has been focused on yield and disease resistance This has been achieved by crossing materials from the three genetic groups ‘Criollo,’ ‘Forastero,’ and their hybrids ‘Trinitario.’ It is expected that the recent reclassification of cocoa into 10 genetic groups and the mapping of cocoa genome will accelerate the selection of plant materials adapted to current production challenges Cocoa is susceptible to a number of pests and diseases that are location specific and cause an estimated loss of 30%–40% of world’s production The causal agents of the major pests and diseases are fungi, virus, and insects (Table 2) Cocoa swollen shoot virus is one of the main threats to cocoa production in West Africa The crop is also susceptible to many obligate hemiparasitic plants The pests and diseases management options are similar to those recommended for coffee Growth and Development T cacao has nine principal growth stages as per the BBCH (Biologische Bundesantalt, Bundessortenamt und Chemische Industrie, Germany) growth classification scale Growth stage includes seed germination where the seedling exhibits a fast growth of the tap root on which rootlets are formed These rootlets develop further into lateral roots for nutrients acquisition Growth stage comprises leaf development on both principal stem and lateral branches Leaf growth is characterized by a leaf flush where about 10 leaves initiate simultaneously and expand for about 40 days before the next flush Growth stage includes the elongation of the principal stem and the development of jorquette of lateral branches and chupons that occur 1–2 years after planting Growth stage consists in the elongation of the lateral branches The growth stage in the BBCH scale does not apply to cocoa, but only to cereals Growth stages and entail the emergence of the inflorescence and flowering, respectively A cocoa tree can produce up to 120 000 flowers per year, from which only 0.5–5% reach maturity Growth stages and correspond to the development Figure Elite cocoa clones grafted on mature trees used as rootstocks Encyclopedia of Applied Plant Sciences, Second Edition, 2017, 420–425 Other techniques 3.1 Minimally processed foods Source: http://www.paleo-britain.co.uk/just-eat-real-food/ 3.1 Minimally processed foods The purposes of minimally processed foods Source: Bansal et al (2015) 3.1 Minimally processed foods Types of minimally processed foods Source: Bansal et al (2015) 3.1 Minimally processed foods Methods available for shelf-life extension of minimally processed products Source: Bansal et al (2015) 3.2 Hurdle systems Source: Rahman (2015) 3.2 Hurdle systems Drying, steaming, blanching Source: Pal et al (2017) 3.3 Addition of natural preservatives Source: Carocho et al (2014) 3.3 Addition of natural preservatives Source: http://naturalsociety.com/37-better-food-preservatives-antimicrobials-chemical-crap-put-food/ 3.3 Addition of natural preservatives Source: http://naturalsociety.com/37-better-food-preservatives-antimicrobials-chemical-crap-put-food/ 3.4 Edible films Source: https://www.slideshare.net/LatikaYadav/edible-coatingnew-15019835 3.4 Edible films Source: https://www.slideshare.net/LatikaYadav/edible-coatingnew-15019835 3.4 Edible films Source: https://www.slideshare.net/LatikaYadav/edible-coatingnew-15019835 3.4 Edible films Source: https://www.slideshare.net/LatikaYadav/edible-coatingnew-15019835 3.4 Edible films Source: https://www.slideshare.net/LatikaYadav/edible-coatingnew-15019835 References [1] Ahvenainen, R 2003 Novel food packaging techniques Elsevier [2] Gould, G.W 2012 New methods of food preservation Springer Science & Business Media [3] Jermann, C., Koutchma, T., Margas, E., Leadley, C., Ros-Polski, V., 2015 Mapping trends in novel and emerging food processing technologies around the world Innovative Food Science & Emerging Technologies 31, 14-27 [4] Lozano, J.E., Anon, C., Barbosa-Canovas, G.V., Parada-Arias, E 2000 Trends in food engineering CRC Press [5] Señorans, F.J., Ibáñez, E., Cifuentes, A., 2003 New trends in food processing Critical Reviews in Food Science and Nutrition 43(5), 507-526 ... processing line Milk processing Storage  Separating  Homogenizing  Pasteurizing / Ultra-high-temperature processing / Cooling  Filling Raw milk storage „„ „„ „„ „„ Milk processing Milk processing involves... accompanied by an increase in accessibility of the canned seafood protein component, with a 10.1% increase in smoked surf clams, an 8.5% increase in smoked mixed seafood and an 8.6% increase in smoked... Integrative Medicine Integrative medicine is a holistic approach to healthcare, that takes into account the whole person, including body and mind in the healing process A major component of integrative

Ngày đăng: 10/07/2020, 23:24

Từ khóa liên quan

Tài liệu cùng người dùng

  • Đang cập nhật ...

Tài liệu liên quan