Cocoa Foods

Cocoa Theobroma cacao or The food of Gods Characteristics of cocoa plant Tree height from 15 – 25 ft. 20-50 fruits per year Pre requisites for tree cultivation warm and humid environment . Temperatures of 18-35 degrees with high humidity

Top Cocoa Beans Producers in 2010 Top cocoa producers Top Cocoa Beans Producers in 2010 (million metric tons)  Ivory Coast 1.242  Indonesia 0.844  Ghana 0.632  Nigeria 0.360  Cameroon 0.264  Brazil 0.235  Ecuador 0.132  Togo 0.102  Dominican Republic 0.058  Peru 0.047 World Total 4.082

Types of cocoa tree Criollo Cocoa tree Forastero Cocoa tree

Composition of coca beans

Fermentation of coca beans Fermentation within 24-48 hours after breaking the cocoa pod. 5-7 days on average cut 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.

Fermentation The pulp around the beans is sticky and needs to be separated. The pulp starts loosening from the bean in the 1st microbial stage. Turning of the beans aids to the fermentation process In 1st 2 processes the temperature rises due to the exothermic reactions to almost 49-54˚C By the end of 3rd stage, the temperature drops rapidly and most of the pulp has drained away as a liquid.

External appearance of cocoa beans

There are 3 stages of fermentation: Anaerobic yeasts Sugar  Alcohol + CO₂ 24-36 hrs Rise in temperature pH < 4 acidic Low oxygen Bean death on second day occurs due to acetic acid and alcohol

Stage 2: Lactic acid bacteria Sugar & organic acids  Lactic acid LAB are present from start but only become dominant in 48-96 hrs

Stage 3: Acetic acid bacteria Also present from start but become significant at the end when the aeration increases Alcohol  acetic acid Exothermic reaction Increases temperature to 50˚C

Schematic representation of Fermentation of coca seeds

Curing Acetic acid penetrates into testa (husk) of cocoa beans. High 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 precursors Proteins are degraded by enzymes to polypeptides and amino acids Reducing sugars (glucose/ fructose) are released. Reduction of astringent and bitter taste Part of polyphenols oxidized into large tannin molecules Part of polyphenols and theobromine/caffeine (20%) diffused and exudated from the bean

Importance of fermentation & curing There is no chocolate flavor in cocoa bean without fermentation Chocolate flavor precursors are formed during fermentation which help in further flavor development

Imporatance of fermenattion & curing Fermentation helps in the separation of pulp and beans Omission of fermentation prevents the possiblity of ever developing a true chocolate flavor and defect cannot be removed by later attempts of fermenting With lower temperatures the putrefaction bacteria will start to proliferate and longer fermentation would cause hammy off-flavors typical for over fermented cocoa beans

Drying Extended process of fermentation Superficial browning in cocoa beans continues to deepen Slow but progressive loss of moisture Loss of astringency & bitter tasteloosening of the shell from the bean Shrinking of furrowed cotyledons into 2 almost separate halves Moisture content reduced to 6% The enzymatic action as evidenced by colour changes in the bean should be allowed to proceed to conclusion

Drying If the beans are dried too quickly some of the chemical reactions started in the fermentation process are not allowed to complete their work and the beans are acidic with a bitter flavor. If the drying is too slow moulds and off flavors can develop. Temperature should not exceed 65˚C Types of drying: sun-drying mechanical drying

Importance of drying Sun-drying is best for good quality Significant lowering of strong acid/sour flavor: volatile acetic acid evaporates through husk during slow drying non-volatile lactic acid is partly transported by water from the bean to the husk Strong oxidation browning of polyphenols leading to reduced astringency and bitterness Flavor forming reactions occur

Roasting Dried beans are artfully roasted at 200˚F to 250˚F for one to two hours in order to develop the flavor of the beans. The beans become brown in color and friable (brittle).

Changes occurring in roasting Development of pleasant aromatic complex (chocolate flavor) Evaporation of organic acids and astringents of volatile nature Chemical modification of tannins and other non-volatile that remain, with consequent reduction of bitterness Darkening of cotyledon color to deep attractive brown Elimination of excess moisture Loosening the shell from cotyledon