Coffee

Family – Rubiaceae
Genus – Coffea
Species – arabica and canephora
Two Types of Coffee About 90 Coffea spp in Africa
Arabica, C. arabica
Tetraploid, self fertile
Ethiopia highlands
>1600m
15-24°C
1300 mm
Best quality
Susceptible to rust

Robusta, C. canephora
Diploid, self incompatible
Rain forest of Congo basin
<750m
24-30°C
1550 mm
Less flavor, acidity
Resistant to rust

Two Types of Coffee About 90 Coffea spp in Africa
Arabica, C. arabica
Medium size tree
14-20’ tall
Medium vigor
Leaves
Smaller
Thinner
Seedlings uniform

Robusta, C. canephora
Medium to large tree
Up to 32’ tall
Vigorous
Leaves
Larger
Thicker
Seedlings variable

Distribution of Cultivated Coffee
Coffee Production and Yield
World Coffee Production
Brazil
21.1%, arabica
Only country with frost possibility in coffee zone
Colombia
13.9%, arabica
Indonesia
7.3%, robusta
Other important producing countries
Vietnam, Mexico, Ethiopia, India, Guatemala, Ivory Coast, Uganda
Major Consumers
High proportion imported by developed countries
USA 23%
EEC 39%
The Seed of the Fruit is the Economic Part A Drupe like a Peach
Both begin bearing in 3-4 years
Time to mature fruit
Arabica, 7-8 months
Robusta, 11-12 months
Productive for 20-30 years
Both need pruning for best production
The Coffee Fruit is called a Cherry
Exocarp
Red skin
Mesocarp
Sweet pulp
Endocarp, hull
Testa (silvery)
Bean (embryo and cotyledons)
The Coffee Fruit is called a Cherry
Exocarp
Red skin
Mesocarp
Sweet pulp
Endocarp, hull
Testa (silvery)
Bean (embryo and cotyledons)
Parchment coffee is the bean, testa, endocarp
Coffee Tree Growth Cycle
Dry and/or cool season
Floral initiation
Reduced vegetative growth
Wet season
Flowers open, fruit set and begin development
Active vegetative growth
Dry and/or cool season
Fruit ripen
Flower buds initiate
Reduced vegetative growth
Coffee Tree Growth Habit
Orthotropic stem
Erect growth
Plagiotropic stems
Horizontal secondary stems growing off of orthotropic stems
These are the fruiting wood
Coffee Farmers
Grown under many conditions
Plantations and smaller farmers
Under shade and in full sun
Monoculture and mixed farming systems
Coffee Production
Propagation
For arabica
Most is done by seed
Clonal propagation
Hybrids
Robusta types
Coffee Production
Planting
Slightly acid (pH 5.2 to 6.3) well drained soil
Beginning of wet season
Vertical position or 30° angle
Spacing – need light for fruit ripening
Arabica, 1350 trees/ha
Robusta, 900-1000 trees/ha
Time to fruiting
Take 3-4 years to obtain mature plant
Fruit on year old wood

Shade and Coffee Production
Both species are understorey trees
Well adapted to shade
Initially coffee was planted under shade
Small holders may use mixed farming
Later unshaded plants were shown to produce higher yields
Shade and Coffee Production
Coffee Production
Training/Pruning objectives
Maximize # plagiotrophic stems (fruiting wood)
Shape trees
Maximize use of space
Ease of management
Maintain open tree to allow good light penetration
Minimize biennial bearing
Remove diseased and dead wood

Single Stem Training(Central leader)
Cut back orthotropic stem
Encourages plagiotropic stem formation
Repeat for 3-5 years
With each cycle the tree gets bigger
Lower limbs die due to lack of light
Rejuvenate after 3-5 years
To reduce size of tree
Cut back to 40-50 cm height
Single Stem Training(Central leader)
Cut back orthotropic stem
Encourages plagiotropic stem formation
Select one orthotropic as new leader
Repeat for 3-5 years
With each cycle the tree gets bigger
Lower limbs die due to lack of light
Rejuvenate after 3-5 years
To reduce size of tree
Cut back to 40-50 cm height
Single Stem Training(Central leader)
Cut back orthotropic stem
Encourages plagiotropic stem formation
Select one orthotropic as new leader
Repeat for 3-5 years
With each cycle the tree gets bigger
Lower limbs die due to lack of light
Rejuvenate after 3-5 years
To reduce size of tree
Cut back to 40-50 cm height
Multiple Stem Training(Modified Central Leader)
Leave 2-8 orthotropic stems
Pruning
Cut back (or bend) orthotropic stem
Encourages orthotropic stem formation
Select several orthotropic stems to be new leaders
Eliminate growth in center of tree
Multiple Stem Training(Modified Central Leader)
Leave 2-8 orthotropic stems
Pruning
Eliminate growth in center of tree
Continues growing taller
Cropping area moves higher
Multiple Stem Training(Modified Central Leader)
Leave 2-8 orthotropic stems
Pruning
Cut out wood in center
Continues growing taller
Cropping area moves higher

Rejuvenation every 4-6 years
Need to lower fruiting surface
Allow basal suckers to grow

Multiple Stem Training(Modified Central Leader)
Rejuvenation every 4-6 years
Allow suckers to grow
Remove old branches
Stump with “lung”
Once suckers begin to grow remove “lung”

Harvest
Most done by hand
Ripe berries only
Pick every 8-10 days
In Brazil, allow cherries to dry on tree
Machine harvest in Brazil
Oscillating fingers
7-9% immature fruit

Disease and Pests Problems
Losses due to diseases
Africa 15%
Asia 10%
S. Am. 12%
Coffee rust (Hemeleia vastatrix)
History
First in Sri Lanka in 1880
Now throughout world
Control
Robusta/hybrids resistant
Less serious above 1700 m
Cu fungicides
Coffee Berry Disease (Colletotrichum)
Cause berry rot
Disease and Pests Problems
Insert Fig 8.4, p 87
Losses due to pests
Africa 20%
Asia 15%
S. Am. 15%
Coffee Berry Borer
History
Originate in Africa
Now throughout world
Damage
Larvae feed on bean
Control
Berry removal
Chemicals
IPM
Monkeys, birds
Coffee Processing
Bean Processing done on the Farm
Wet Method
Start on Harvest Day
Separate trash and defective berries by flotation
Good berries are depulped same day
Fermentation
Only to remove mucilaginous covering
Excessive heat destroys flavor

Wet Method
Washed
Water under pressure
Dried – spread out to dry
Sun
Artificial heat
Best quality
Gives coffee that is cleaner, brighter, fruitier, better acidity

Dry Method (Natural Method) (Most traditional and least expensive)
Drying (Indonesia, Ethiopia, Brazil, Yemen)
Initial drying done on trees
Spread on concrete, tile or matted surface
2” thick and constantly raked
3-15 days until specific moisture
Pergamino is dry and crumbly

Dry Method(Most traditional and least expensive)
Remove pericarp
Mortar and pestle or machine
Chaff removed via winnowing and picking
Sorted by size, shape, density and color
Packed in 60 kg bags for processing

Industrial Processing(Usually by importing company)
Grading process
Redry and clean the parchment beans before using
Remove testa (hulling and polishing)
Sort on size and density
Roasting (370°F to 540°F)
Removes moisture
Light roast lose 3-5% moisture
Dark roast lose 8-14% moisture
Time (up to 30 min) determines flavor
Decreasing the amount of
Chlorogenic acid
Trigonelline
Grinding

Industrial Processing(Usually by importing company)
Caffeine Reduction
Add water to beans
Extract with
Methylene chloride and ethyl acetate
Residual solvent removed via low level steam drying
Caffeine can be recovered with water extraction of organic solvent

Industrial Processing(Usually by importing company)
Once ground the beans lose flavor rapidly
Grinding
Coarse to medium (600-1100 μm)
Home percolators
Fine grinds (Automatic percolators)
Europe (400-500 μm)
USA (600-700 μm)
Industrial Processing(Usually by importing company)
Instant Coffee
Extract soluble solids, volatile aroma and flavor with water
Drying
Drum drying – poor appearance
Spray drying – loses flavor volatiles
Freeze drying – best product
Best retention of flavor
Produces granules
No evaporation so no loss of flavor
Coffee oil for head space aroma
Any Questions?

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