COCOA PROCESSING

Botanical Name: Theobroma cacaoCocoa trees grow best in the tropical rainforests The cocoa tree grows to a height of 15 – 25 ft. A single tree produce 20-50 fruits per year.The pods are 10-18 cm in diameter, having thick leathery rinds

containing 20-50 beans inside in rowsThe seeds are embedded in white or pinkish pulp

Varieties of cocoa treesThere are three broad types of cocoa - Forastero and Criollo, as well as

Trinitario, a hybrid of the two. Forastero

Forastero is hardy and vigorous, producing beans with the strongest flavour.

CriolloWith its mild or weak chocolate flavour, Criollo trees are not hardy

and produce softer red pods, containing 20-30 white, ivory or very pale purple beans.

Trinitario Plants are not found in the wild as they are cultivated hybrids of the other two types.

Composition of cocoa

Cocoa Processing

HARVESTING:Only ripe pods are harvested.

PRE FERMENTATION STORAGE: 3 to 5 days

Ensures correct nib acidification Enhances pre-fermentation activity inside beans

Facilitates rapid rise in temperature Imparts stronger chocolate flavor

POD BREAKING AND COLLECTION OF WET BEANS:Pods are broken without causing damage to beans

Only good beans are collectedDiseased, germinated and caked beans are discarded.

FERMENTATION AND CURING Fermentation has to be carried out within 24-48 hours after breaking the

cocoa pod. It takes about 5-7 days on average and varies according to the species. Forastero - 5–7 days, Criollo- 1-3 days It is responsible for the chocolate flavor and aroma in cocoa and also

external browning of beans. Cocoa beans do not themselves undergo a fermentation at all It is pulp surrounding the beans which is fermented, while simultaneous

‘curing’ process takes place within the beans

Microbial aspects Micro-organisms are responsible for the breakdown of

the pulp that surrounds the beans.This result in the death of the beans and enables the

formation of cocoa flavor precursorsThe pulp is an excellent medium for the growth of micro-

organisms since it contains 10-15% of sugars.

Stages of FermentationStage 1Anaerobic yeasts Sugar Alcohol + CO₂ 24-48 hrs (no air circulation) Rise in temperature pH < 4 acidic Low oxygen Bean death on second day occurs due to acetic acid and

alcohol penetration inside the bean.

Stage 2:Lactic acid bacteriaSugar & organic acids Lactic acidLAB are present from start but only

become dominant in 48-96 hrsStage 3:Acetic acid bacteriaAlso present from start but

become significant at the end when the aeration increases

Alcohol acetic acidExothermic reactionIncreases temperature to 50˚C

Factors influencing Fermentation Pod maturity Pod storage Quantity of beans Quantity of pulp Type of cocoa Duration Seasonal effects Pod diseases

End point of fermentation Bean color changes to brown, becomes plump and filled

with a reddish brown exudate Testa becomes loose and detached from the cotyledons Longitudinal halves of cotyledons show bleached

appearance in the centre with a brownish ring at the periphery

When 50 % of beans show these signs, the lot can be taken out for drying

CuringHigh temperature and influx of acid:

Kill the bean Disrupt the internal structure

Cocoa beans are composed of white cells (fats, proteins) and purple cells (polyphenols)

Due to the disruption compounds in the beans mix and interact within themselves.

Reactions between storage proteins, enzymes (proteolytic, polyphenol oxidase, invertase) and polyphenols result in formation of the crucial chocolate flavor precursors

Chocolate flavor precursorsProteins are degraded by enzymes to polypeptides and

amino acidsReducing sugars (glucose/ fructose) are released.Reduction of astringent and bitter tastePart of polyphenols oxidized into large tannin moleculesPart of polyphenols and theobromine/caffeine (20%)

diffused and exudated from the bean

Importance of Fermentation & CuringThere is no chocolate flavor in cocoa bean without

fermentationChocolate flavor precursors are formed during

fermentation which help in further flavor development

DRYING:Extended process of fermentationSlow but progressive loss of moistureLoss of astringency & bitter taste Loosening of the shell from the beanMoisture content reduced to 6%

ROASTING:Dried beans are roasted at 200˚F to 250˚F for 1-2 hours in

order to develop the flavor of the beans.The beans become brown in color and friable (brittle).

GRINDING :The heat produced during grinding causes cocoa fat to

melt and the melted fat carries with it, in suspension, finely ground particles of cocoa. This is known as ‘Cocoa mass’, ‘Chocolate liquor’ or ‘Bitter chocolate’

This mass solidifies at about 30˚C

PRESSING OF NIBSFilter-pressing to separate out a major part of fat (cocoa

butter)The amount of fat left in the pressed cake can be varied

by the conditions of pressingThe pressed cake is used for producing cocoa powder

COCOA PRODUCTSCocoa butter also called theobroma oil, is a pale-yellow,

pure, edible vegetable fat.

Cocoa powderEnd product of cocoa solids which are low-fat components

and are rich in flavonoids

Chocolate A food preparation in the form of a paste or solid block made

from roasted and ground cacao seeds, typically sweetened.

Researches....Improvement of Cocoa Beans Fermentation by LAB Starter

Addition - M. T. A. Penia Kresnowati, Lenny Suryani, and Mirra Affifah

Addition of microbial starter was thus suggested to improve the

cocoa bean fermentation process. The addition of LAB starter was observed

to accelerate the growth of both lactic acid bacteria and acetic acid bacteria,

leading to the increase in the ethanol, lactic acid, and acetic acid

concentration. Overall it increases the fermentation index and potentially

shortens the fermentation time.

Dynamics of Cocoa Bean Pulp Degradation during Cocoa Bean Fermentation: Effects of Yeast Starter Culture Addition - Laras Cempaka1, Lienda Aliwarga1, Susanto Purwo & Made Tri Ari Penia Kresnowati

This article discusses the effects of the addition of

Saccharomyces cerevisae var. Chevalieri starter culture on cocoa bean

fermentation. The dynamics in the yeast concentration, sugary pulp

compounds and metabolic products were measured during fermentation. A

higher fermentation index was measured for the cocoa bean fermentation

with yeast starter culture, 1.13 compared to 0.84. In conclusion, this

method can potentially be applied to shorten the cocoa bean fermentation

time

Reference...The Functional Role of Microorganisms in Cocoa Bean

Fermentation V. Thi Thuy Ho, J. Zhao, G. Srzednicki and G. Fleet

www.c-spot.com - chocolate flavor profilesHarvesting and Processing Cocoa Beans'Theobroma Cacao' – The Cocoa TreeCocoa – production and processing -Kokou Edoh Adabe

& E. Lionelle Ngo-Samnick