cocoa

Family: Sterculiaceae

Genus: Theobroma

Species: Cacoa

Scientific Name: Theobrama cacao L.

Cocoa is the third important beverage crop next to coffee and tea.

Cocoa is the tropical crops

Important item of confectionary industries and is the only source of chocolate

contain percentage

fat 57

protein 7

carbohydrate 7

theobromine 1.7

moisture 6

ash 2.7

minerals 1.1

pectin 4.1

fiber 2.1

cellulose 1.9

pentosans 1.2

Mucilage & gums 1.6

Tannin & acids 6.6

Cocoa is a native species of tropical humid forest on the lower eastern equatorial slopes of the Andes in South America.

Theobroma literally mean “food of the Gods”. Cocoa was domesticated and the produce used

for the consumption for the Maya and Aztecs. The 1st European drinks cocoa is a Spanish

after conquered Mexico.

Cocoa is the one of the 22 species assigned to the genus Theobroma cacao and only the species have value and economic important.

Other species : T. bicolor T.angustifolium T. grandiflorum

The tap roots of cocoa grows predominantly downward with only few branches.

Under suitable growing condition when the soil is deep they grow to a depth of about 150cm.

The function of the roots is considered to be anchorage.

The main feeding roots are those arise from the tap roots and grow laterally

Most of these roots just concentrated below the soil surface up to the depth 15 to 20cm.

The lateral spread of such roots will be 120 to 150cm around the adult cocoa tree.

The bulk of feeding roots of cocoa is concentrated near the surface.

Any digging of soil can caused injuries to the roots

The cocoa rooting pattern can be modified to an extent by the environment.

Cocoa grow in tiers. The shoots of seedlings that grow upwards is

called “chifon”. After growth 1 – 1.5M chifon cease 3 to 5

lateral branches . Lateral branches called “ fan”. The point which fan arise is called “

jorquette”

Leave of the fan are arranged in one plane and are alternate.

Leave arrangement of chifon will be spiral. Chifon leave have longer petiole.

COCOA FLOWERS.

Cocoa flowers are borne on thickened leaf axils on stems called “cushions”.

In every cushions is up 50 flowers. The cocoa flowers is a compressed cyme and have 5

sepals, petals and 10 stamens in two whorls . Every ovary have 5 united carpels Every flowers contained 40-60 ovules. The flowers which not fertilised will be falled within 24

hours

The pollination was assisted by the small insects called ceratopogonid midges.

The insects are small and barely visible to the naked eyes.

The midges are attracted by the pigmented tissues of the staminodes and the guidelines of the petals.

Flowers starts opening in the afternoon and are fully opening by the forenoon the next day.

The cocoa fruits is a botanically a drupe , often called “pod”.

Each cocoa pod contained 30 – 50 beans. Classifications cocoa pod: a) Criollo b)Forastero c) Trinitario

criollo forestero Trinitario

Pod yellow or red when ripe . Deeply 10 furrowed,markedly

warty.conspicuosly pointed. Pod wall too thin, seed large and oval. Cotyledons white or pale violet which are less

astringent. The beans fermented quickly but yield is very

poor.

Produces highest quality cocoa. Susceptible to stress. Not adaptable all situations. Clone :

A) Central American CriolloB) Venezuelan Criollo

Unripe is green and turn yellow on ripening. In conspicuously ridged and furrowed. Surface smooth, end rounded or bluntly pointed. Pod wall very thicked. Seed flattened ,fresh cotyledons deeply pigmented

and dark violet giving an astrigent product. High yield and hardy. The beans take 5- 6 days for fermentation

Origin from Trinidad. Cross criollos x forasteros. Hetetrogenous and exhibits a wide range of

morphological and physiological characters. Characteristic base on range criollo and

forastero.

The distribution of germplasm collection must be thoroughly international recognized agencies.

A) International Cocoa Genebank , Trinidad.B) Lembaga Koko Malaysia

C) Ghana Cocoa Institute

Priorities in Breeding :a) yield improvement.b) disease ( vsd,black pod etc)c) Pestd) retention flavorse) adaption environmentf) tree shape, pod size and beans characters

The genetic base of cocoa is very narrow. The type of genetic will be based:a) Yieldb) Pod and bean characterc) Reaction of pest and diseased) Adaptation to the environment

Cross – pollinated not advisable. Bud wood from vegetative materials more ideal The introduced material will be quarantined

until be certified from pest & disease

Selection of seedling is can contribute high yield through adaption of :

a) Space and planting distance.b) Shade tolerancec) Soil conditiond) Nutrient supply.

Yield criteria:a) Plants yielding not less than 100pods/ yearb) Each 1 pod 350gms – 400gmsc) Fermented 35-40 beans weight 1.0gram dry

bean.

Hybrid method is one of the method to obtain good varieties.

Method of hybrida) Hand pollinationb) Pre selectionc) Clonal seeds garden

HAND POLLINATION

Problem in hybridization

a) Can caused in breeding

b) Can caused no pod sets

c) Hybrid can caused high seedling

The important climatic factorsa) Temperatureb) Rainfallc) Altitude and latitude

15 to 32 °c and this range considered optimum.

These temperature limits set the latitude limits for the best growth of cocoa to within 8° north and south of the Equator

Requirement annual rainfall range 1500mm to 3500mm.

Lower than 1500mm may cause the cocoa stress.

If the rainfall more than 3500mm were favor incidence of disease such as black pod (Phytophthora palmivora).

Cocoa is grown in the wide range of soil. Soil of high rainfall areas are relatively coarse

textured and acidic to neutral in reaction. Very coarse sandy soil are not suitable for

cocoa. The sandy loam soil is the suitable for cocoa

cultivation.

Cocoa can be propagated froma) Seedsb) Vegetative propagation.

Seed propagations is the cheap and easy. However, the seedling is highly variable genetically.

Vegetative propagation can be developed as followed:

a) Buddingb) Rooting of cuttingc) Grafting

Planting a) Cocoa seeds can be sown directly or seedling

planted anytime if soil moisture condition are suitable.

b) The best time for field planting of seedling would be of pre-monsoon (march-april, october-december)

The spacing would be based on the:a) Topographyb) Clonec) Shade patternd) Soil typee) Planting density

Normally the planting distance:1.7m x 1.7m or 2.7m x 2.7m

Cocoa normally cultivated under shade Type of shade

1) Gliciridia2) Coconut3) Legume trees (ex: petai, petai belalang, etc)

In the early stage, 75% shade required. This is brought it down to 25% after matured.

The fertilizer recommendation for cocoa under average management is 100:40:140/plant for a year.

For cocoa under better management where the average annual yield is more than 60 pods, double this dose is tentatively recommended.

Feeding root of cocoa are concentrated on the surface soil, occurring within of 15 cm from the surface.

They are concentrated in a radius of 120 to 150 cm in established (adult cocoa)

Fertilizer may preferably be applied in shallow basins of 120 to 150cm radius and raked in without serious damage to the roots

The genera recommendation in most cocoa-producing countries is to broadcast fertilizer in the entire field without any soil tillage.

Timing the application of fertilizer:a) The stage activity and the season of moisture

availability may have to be consider.b) For irrigated cocoa, fertilizer may be applied in four

equal split during may-june, september-october, december and february.

c) For young cocoa in field, the dose of fertilizer may be one-third the annual dose for adult plant for a first year and two-third for the second year.

d) A cocoa under good management will start giving reasonable yield from the third year, full doses of fertilizer are supplied from this point on.

The purpose of pruning:a) To control the growthb) Excessive development of branchesc) To facilitate harvestingd) To control pest and disease

The first tier should be developed at height not less that 1 to 1.5m

If plant jorquette at lower height, the stem with the developing fan maybe nipped of just below the jorquette.

The chupon should be removes below the height.

The weeds control in cocoaa) Circle weedingb) Slashingc) Selective weeding

Top working is useful to rejuvenate old unproductive plant and also to convert genetically poor yielders to high yielders.

The technique was standardized at the Cadbury plantation

The technique consist of snapping back at the desired tree below the jorquette after the cutting half way

Cocoa does not flower uniformly throughout the year and there are peaks of flowering within 3 months of the year.

These periods of peak flowering are often for the different region.

This depend on climate factors (ex: Ghanaian cocoa)

Normal flowering at peak may-july

Several factors to influence the floweing and fruit set:a) Geneticsb) Environmental factors

i) Moisture stressii) Temperatureiii) Solar intensity

c) Physiological factors

The pods mature is about 150 to 170 days from the days of pollination.

The periods varies depending on environmental conditions.

The stage of maturity of pods is best judged by change of color of the pods

Unripe pods shows green or red depend on clone or hybrids

The change of color start from the grooves on the pods and then split into the entire surface

The pods start change the color is shows ripe pods and can be remain on the tree within 1 month

The interval is between 18 days to 1 month The safer periods to harvest at fortnightly interval This is to prevent the incident of the black pod

disease. Fruits are borne on the cushion. The good

harvesting practice is to avoid cushion damages on the pods.

The harvested pod can be store for 2 – 7 days. This enhances the pre-fermentation activity

including a) Reduce acidityb) Rise in temperaturec) Increase chocolate flavour

Cocoa is affected by more than 1500 insects in different cocoa growing countries in the world

Only a small numbers is of economic important Among the major pest infecting cocoa:

a) Cocoa pod borerb) Tea mosquito bugc) Mealy grey weevild) Cockchafer beetlee) Ratf) squirrels

Pot rot (Phytopthora palmivora, P capsici,P megakarya and P citrophthora)

The pod become black and occurred during rainy season.

The whole pod will infected by the fungus. The beans however can be escaped if the infection

not serious. Regular pruning can minimized the infection or

Bordeaux mixture or copper oxychloride at 15 days interval

BLACK POD

Charcoal pod rot(Lasioplodia thebromae) The pod occurs during dry season. Pale yellow spot on the pod and enlarge into

chocolate brown. Use Rovral ( Iprodione) or bordeaux mixture

CHARCOAL DISEASE

Monilia pod rot( Moniliophthora roreri ) The infection only in young pod and become

black and falls. The control by removed the infection young pod

by weekly interval

MONILIA DISEASE

Vascular streak dieback( Oncobasidium dieback )

the disease may occur on the main stem of seedling or on the branch of older seedling.

1st symptom the pale yellow on second or third leaf at seedling stage.

Treatment use fungicide Thiram

VASCULAR STREAK DIEBACK

Pink Disease( Corticium salmonicolar) Fan branches and small twigs are infected and

pinkish color . Removed the branches infected and sealing

with shellcote or Bordeaux mixture.

Ceratocystis wilt ( Ceratocystis fimbrata) The disease caused by damaged beetle borer

or pruning wounds. The mature leaves will wilted and dry and

remain at the branch for several weeks Used insecticide and fungicide mixture or

minimized wounding during pruning and harvesting

Fermentation The raw cocoa beans are covered with sugary

mucilaginous pulp . The beans covered with pulp will called “wet

beans “ The economical part was called “nib”. The raw nib was bitter and no aroma , flavor or

chocolate taste.

The chocolate flavor developed by 2 process. Fermentation ( grower) Roasting ( manufacturer)

Heap fermentation

The pulp contains 84.5% water, 10% glucose and fructose, 2.7% pentosan, 0.7% sucrose, 0.6% protein, 0.7% acids and 0.8%inorganic acid.

The changes due to development of microbial populations

This continues 24-36 hours activity of yeast leads to the production of CO2

at the aerobic process.

This process to developed of lactic acid bacteria which assist in the breakdown of sugar

1) Ripeness of pods2) Pod disease3) Types of clone4) Quantity of cocoa5) Duration6) Turning7) Seasonal effect

2 types1) Box maturation: the bean set for fermentation in the

box are to be mixed as usual on the third and fifth days. Five extra turn may occur on the sixth and seventh days, and beans may taken out on the eighty day.

2) Dried maturation: beans may be kept to thickness of 25 cm and dried at 50oC. Stacking to depths lower or higher than 25cm result in poorer quality presumably because of too fast drying of bean in the former and lack of adequate aeration in the latter.

Box maturation Dried maturation

Traditional standard methodsa) Heap methodb) Tray methodc) Box methodd) Basket methode) Curing on drying platform.

1) Color of the beans2) External shell color3) Smell of fermenting mass4) Development of heat5) Plumpy nature of the beans and color of the

exudates.

Sun drying Artificial drying

International standard stipulate:1) The ambient humidity must not exceed 70%2) The bag must be stored at least 7cm from the

ground, normally on a duckboard to allow free air circulation

3) There must be passage at least 60cm wide between the walls and the bags and between bags of different type of cocoa.

4) Protection against storage pests/rodents must be ensured.

5) Step must be taken to avoid contamination by odors, off flavor or dust

6) The moisture content should be checked at frequent intervals