4- 010844

DRYÏNG METHOD FOR CACAO BEANS

The présent invention relates to method of reducinglevels of acidity in fermented beans of the cocoa plantTheobroma cacao prior to drying of the beans, to improveand enhance the cocoa flavour of such beans.

The beans of the cocoa plant (Theobroma cacao) are theraw material for cocoa, chocolaté and natural cocoa andchocolaté flavouring. As described by Rohan ("Processingof Raw Cocoa for the Market", FAO/UN (1963)), raw cocoabeans and extracted from the harvested cocoa pod, fromwhich the placenta is normally removed, the beans arethen "fermented" for a period of days, during which thebeans are killed and a purple pigment is released fromthe cotylédons. During fermentation "unknown" compoundsare formed which on roasting give rise to charàcteristiccocoa flavour. Rohan suggests that polyphenols andtheobromine are implicated in the flavour precursorformation. After fermentation, the beans are dried,during which time the characteristic brown pigment forms, and they are then stored and shipped.

Fresh cocoa beans contain 35%-45% moisture according toRohan. An analysis in Rohan of dried unfermented WestAfrican cocoa beans showed that the moisture content was3.65%, the level of tannins (which includes thepolylphenols) was 7.54% and the level of theobromine was1.71%. Cocoâ pulp at pH 3.3 is an idéal medium for theformation of alcohol and organic acids by fermentation.The organic acids in their unionised form are able tocross membrane barriers and so enter the beans where theyencounter a pH of 6.5 and ionise immediately. Theresulting flood of hydrogen ions kills the living cells 010844 2 in the beans by disrupting their normal energy andtransport mechanisms. Enzyme/'substrate reactions, whichunder normal conditions would resuit in the ordereddevelopment of a cocoa seedling, progress chaotically toproduce cocoa flavour precursors from which thecharacteristic flavours of cocoa are derived during theroasting process.

During drying, excess acids diffuse from the beans to theshells where they are lost either by évaporation or bymicrobial décomposition. If the beans are dried tooquickly, water evaporates ahead of the rate of diffusionleading to an unacceptably high concentration of residualacids in the beans. When the beans are roasted toproduce cocoa flavour, high levels of residual acidseither mask any cocoa flavour that is formée or impedethe desired flavour-forming reactions. Either way, thecocoa tastes sharp and acid with very little true cocoaflavour, which is typical of most of the cocoa producedin. Malaysia, Indonesia and other cocoa origin countrieswhere hot air dryers are used. In West Africa on theother hand, most of the fermented cocoa is spread outunder the sun to dry, which may take up to 5 or 6 days.Much lower levels of residual acidity are achieved andmore cocoa flavour is produced from West African beans onroasting. Whereas sun drying is easily managed in WestAfrica where a million or more cocoa farmers may eachproduce no more thari a few bags (62.5 Kg) of cocoa per annum, it ife impractical for estate-scale productionwhere up to 40 metric tonnes of dry beans are producedeach day during peak crop seasons.

At présent cocoa beans are dried either artificially ina current of hot-air, in the cocoa producing countries of 010844 3

South East Asia, or by spreading out the cocoa beans inthe sun to dry in the cocoa producing areas of WestAfrica.

The présent processes for drying cocoa beans are,however, unable to deliver large amounts of good gualitycocoa flavour either because the process is inherentlyinefficient and cannot conveniently be scaled up (sun-dried method) or because the means used to dry the beansproduces high levels of acidity which mask or impair thecocoa flavour produced (hot-air drying method).

It is speculated that organic acids alone are responsiblefor the sharp or acid taste of cocoa produced by the hot-air drying method. However, it is thought unlikely thatthe organic acids themselves account for the excessivelyacid taste, even though they may ultimately beresponsible for it, as there are probably not enough ofthem formed during pulp formation. Furthermore, cocoaflavour intensity and astringency hâve been negativelycorrelated, which suggests that the polyphenolsresponsible for astringency might be the cocoa flavourprecursors. If the enzymatic conversion of polyphenolsto cocoa flavour were inhibited in an acidic environmentthen excess acid would be indirectly rather than directlyresponsible for poor flavour quality, the sharp tastebeing a combination of acidity and astringency rather than acidity alone.

The présent invention seeks to provide a solution tothese problems by providing a means for producingenhanced and improved cocoa flavour from cocoa beans ona commercially useful scale. Whether or not thespéculation set out in the last preceding paragraph is 010844 4 correct, it has been found that the flavour of cocoa canbe improved by the following method.

According to a first aspect of the présent invention,there is provided, a method of processing beans of thecocoa plant Theobroma cacao, the method comprising atleast partially deshelling, and subsequently drying, thebeans.

In the présent application, the term "shell" is used todescribe the seed coat or testa of the cocoa bean. Thedried testa may also be more precisely known as a "hull"or a "husk".

While the invention primarily relates to the processingof the beans of the major cocoa plant species, Th. cacao,the invention is not limited solely to this species andincludes the subspecies Th. cacao cacao and Th. cacaosphaerocarpum. For example, many cocoa varieties arehybrids between different species; an example of such ahybrid is the trinitario variety.

The invention involves at least partially deshellingcocoa beans. The shells may be partially removed or evenmerely opened. In some cases it may be désirable fullyto remove the shells of the beans processed according tothe method. There is also evidence of flavourimprovement if the shell is simply broken to provide anexposed surfdce of nib which may allow the organic acidsto escape. It might not be necessary therefore toseparate nibs from shells completely before drying.

The term "nib" is used in the présent application todescribe a partially or wholly deshelled bean. The term 010844 5 may also descr-ibe a bean which has been deshelled andthen broker, into fragments. Where the bean rem'ains wholeafter removal of the shell, it may also described by theterm "cotylédons".

The removal or opening of the shell of the cocoa beansmay be achieved. by any suitable method, which may bemechanical or Chemical. E-xamples of mechanical techniques, which may be manual ormay be automated using appropriate apparatus, includescoring, scraping, cracking, crushing and/or winnowing.Examples of suitable machines include a rubber crêpingmachine and a custom-built rotating bed of nails. Theshells of the cocoa beans can also be removed manuallybut this is not an economically realistic method.Residual shell particles from beans which hâve beenpartially deshelled or opened could be removed bywinnowing before or after the broken beans hâve beendried and/or roasted.

An example of a Chemical technique is lye-peeling. Lye-peeling is commonly used for vegetable and fruit peelingand may also be suitable for use in the présentinvention. Lye-peeling involves the use of an alkalitreatment of fruit to remove the skins prior to canning.

Deshelled beans or nibs are then suitably dried toproduce the cocoa flavour. The drying process may becarried out in a stream of air which is at an ambienttempérature of from 15°C to 35°C, suitably 20°C to 30°Cand preferably 25°C. The drying at an ambienttempérature may be carried out for a period of from 2 to72 hours, suitable of from 4 to 48 hours and preferably 010844 6 of from 16 to 24 hours. The process may also be suitablycarried out under conditions of ambient humidity. Thisis then followed by drying with air heated to atempérature of from 45°C to 75°C, suitably 50°C to 65°C,more preferably 60 °C to bring the beans to total dryness.Drying at the higher température may be for a period offrom 1 to 12 hours, suitably of from 2 to 8 hours andpreferably of from 4 to 6 hours. Acceptable results canalso be obtained by drying the deshelled beans or nibs atan ambient température alone of from 15 °C to 35 °C,suitably 20®C to 30°C and preferably 25°C.

While the method of the invention primarily hasapplication to air drying processes, as typicallypractised in South East Asia, it may also be used withadvantage in conjunction with sun drying processes astypically used in West Africa. However, it is in the airdrying process that the greatest improvement in cocoaflavour may be achieved.

While it has been stated above that the drying step issubséquent to the deshelling step, it should beunderstood that a certain amount of drying prior to thedeshelling step can be tolerated, even if it is notparticularly advantageous to put the invention intoeffect in this way. The important point is that enoughof the overall drying process should take place after thedeshelling step to enable the advantage of the inventionto be achieved.

There are circumstances, however, when some pre-drying isadvantageous. It has been found, for example, that ifthe skin of the cocoa beans is at least partially driedprior to deshelling, the breaking of the shells may be 010844 7 facilitated under conditions of ambient températureand/or ambient humidity (the term "skin" rs used todescribe the shell of the cocoa bean when the shell iswet). This step may for a time period of from 30 minutesto 6 hours, suitably of from 1 hour to 4 hours andpreferably for 1 hour. The précisé time period to beused will dépend on the amount of beans to be dried andcan be determined by the skilled person in the artwithout any undue burden. Provided that the températureof the cotylédons does not rise above the levelsencountered during fermentation then the enzymicmodifications of the cotylédons, which are believed to beresponsible for the flavour improvement during finaldrying, are unlikely to be affected.

Additionally, the method may advantageously contain aprimary washing step, prior to the drying and deshellingsteps. The removal of mucilage may facilitate thesubséquent breaking of the shells and séparation of nibsand testa.

After drying, roasted or unroasted nibs can be used forproduction of cocoa liquors in the normal way or for theproduction of cocoa butter and cake by filter pressing(of liquor) or by expelling. In general, fermented cocoabeans, dried by the sun or hot-air methods, are normallypacked in jute sacks for storage and transportation.Whole beans are traditionally subjected to a roastingtreatment to develop flavour at températures, typicallybetween 110-Î50°C. The roasting treatment may be precededby a process, such as micronising, which facilitâtes shell removal by winnowing, or winnowing may be carriedout after completion of the roasting stage. In eithercase, the final product of the roasting and winnowing 010844 8 treatments is roasted cocoa nibs, which are then traditionally ground to produce coccliquor may be used directly as an ingrédient in chocolatérecipes (formulations), or may be separately processedfurther, by filter pressing, to produce cocoa butter andcocoa cake. Cocoa cake is subsequently milled to producecocoa powder. In the expelling process, dried beans,with or without a shell or part thereof, are put througha screw press expeller to produce cocoa butter and cake. 10 15

The improved cocoa flavour produced by the method of theprésent invention compared to that obtained by simplytreating the beans by the hot-air methods typically usedat présent is characterised by the flavour having agreater level of cocoa flavour but a reduced level ofacidity, bitterness and astringency.

Cocoa flavour may be classified according to thefollowing categories: cocoa flavour, acid/sharp, 20 astringent, bitter, raw/green, fragrant/floral, brownfruit, late sour and thick mouthfeel. Scores may beassessed on a point System and a high score in a categoryindicates a strong intensity for a particular flavour. 25 As mentioned above, it is possible that the bénéficiairesuit s of the invention are achieved because the partialdeshelling results in a réduction of the level of acidityin the bean. 30 According to a second aspect of the présent invention,there is provided a method of reducing levels of acidityin fermented beans of the cocoa plant Theobroma cacao toimprove cocoa flavour in which the cocoa bean arepartially deshelled, prior to drying the beans, such that 35 the organic acid level in the beans is reduced. 9 010844

Other preferred aspects of the second aspect of theprésent invention are as for the first aspect mutatismutandis.

The invention will now be described by way of examplewith reference to the accompanying Examples which areprovided for the purposes of illustration and are not tobe construed as being limiting on the présent invention.

Example 1: Manual deshelling of beans

Fermented beans, deshelled manually, were dried eitherunder the sun or in a current of air at ambienttempérature or at 40°C. Ail were dry within 48 hours andproduced cocoa liquors which were less acidic andastringent and had more pronounced cocoa flavour thancorresponding liquors produced from whole beans dried forthe same period of time at 60 °C.

First attempts to separate broken shells from nibs useda sink/float process with a solution of sugar in water ora suspension of inert material (limestone or clay) toform a density of gradient. Although reasonablysuccessful on a laboratory scale this was not practicablefor commercial scale production.

Example 2: Manual deshelling of beans and expeller trial 1 tonne of fermented beans was deshelled by hand in orderto provide enough deshelled dried beans for an expellertrial. The deshelled beans were sun-dried and putthrough a screw press expeller. Satisfactory samples ofcocoa butter (considered acceptable for direct usewithout deodorisation) and cake were obtained. 10 010S44

Example 3: Mechanical deshelling of beans usine? rotating bed of nails A device on which beans were eut and torn between a fixedand rotating bed of nails was constructed to provide 50Kg samples of .deshelled nibs for further trials.Deshelled nibs were dried in a current of air at ambienttempérature for 16 hours and then at 60°C to finaldryness. Flavour profiles of cocoa liquors made from thedeshelled nibs, whole beans dried at 60°C throughout andwhole beans subjected to the same drying treatment as thedeshelled nibs are shown below. The liquor from thedeshelled- nibs had more cocoa flavour and was lessacidic, bitter and astringent than those from the wholebeans. The reduced astringency, late sour taste andincreased viscous/thick mouthfeel are indicative ofchanges in the polyphenol chemistry effected by theremoval of the shells prior to drying. Cocoa liquorsfrom the deshelled nibs were also much darker in colour.

Table 1

Whole beans at 60 °C Whole beans 16/60°C Deshelled nibs 16/60°C Cocoa flavour 4.6 4 6.4 Acid/sharp 4.2 4 2.6 Astringent 5.1 5.1 3.5 Bitter 4.3 4.S 3.4 Raw/green 3.7 3.8 2.3 Fragrant/floral 3.9 3.4 4.4 Brown fruit 2.9 2.6 4.5 Late sour 3.3 4.7 2-9 J Thick mouthfeel 3.4 | 3.8 5.3 1 11 010844

The three drying treatments used weré (i) whole beansdried at 60°C throughout, (ii) whole beans - 16/60°C -dried in a current of air at ambient température for 16hours then at 60°C to final dryness, (iii) deshelled nibs16/60°C were dried likewise as (ii). Scores on 10 cmline scale. Higher scores dénoté stronger intensities.The improvements in flavour hâve been confirmed infurther trials. Cocoas hâve been tasted as cocoa liquorsand as plain chocolatés.

Example 4: Mechanical deshelling of beans using rubber crêpinq machine (no pre-washing step and no skin drying step)

Fermented beans hâve also been put through a rubbercrêping machine. A spacing of 3/16 of an inch betweenthe rollers rotating at slightly different speeds tearsthe beans while leaving larger pièces of shell intact.The débris is dropped onto a rapidly rotating cône whichthrows it onto a screen sieve. Pièces of nib passthrough the screen. Larger pièces of shell are retainedfor recycling until the degree of séparation of nib andshell fragments is satisfactory. The efficiency of bothbean breaking on the crêping machine and séparation ofnibs and shells is improved by prior treatment of thefermented beans with a pectolytic enzyme to remove excessmucilage.

Example 5: Mechanical deshelling of beans using rubber crêping machine with pre-washing step and skin drying step

Beans straight from the fermentation box were paddledmechanically under running water for 10 minutes to remove 12 010844 residual mucilage and are then skin dried at 60°C for up LU ôU luillütetï dcpciidiriy Ou txlO bcd dOptii. riOiuGVcil ufmucilage and skin drying facilitâtes subséquent breakingof the beans and séparation of nibs and testa.

Provided that the température of the cotylédons does notrise above the levels encountered during fermentation,the enzymic modifications of the cotylédons, which arebelieved to be responsible for the flavour improvementsduring final drying, are unlikely to be affected.

The skin dried beans were then broken manually or byputting them through the rollers of a machine used tocrêpe latex (known as a rubber crêping machine). Thestainless Steel rollers, which hâve diamond eut surfacesand are at a gap setting of 3/16", rotate at slightlydifferent speeds and so eut, crush and tear the beans.

The débris comprising broken nibs and shells (testa) wasthen dried in a current of air by one of two procedures.The current of air was either passed through the débrisin a box with a base of fine métal or nylon gauze, or thecurrent of air was passed over the débris spread out inthin layers on trays.

The dried débris was roasted, crushed lightly to removeany adhering shells from nibs and winnowed to separatethe nibs and shells. . Roasted nibs containing less thanthe statutory, 1.5% shell were finally milled into cocoaliquor. 13 010844

Example 6: Effects of different drying treatments

Comparative example 6(a)

The previous standard treatment used to dry whole beansis to dry the beans in a current of hot air at 60 °C for48 hours which resuit s in beans with a whole beanmoisture content of 7.5%.

Although washed beans, subjected to the above conditionsof hot bed drying, gave slightly better flavour thanunwashed beans, the flavour improvement, while beingdirectionally similar, was much less pronounced than whenthe beans were broken to expose the nibs prior to drying,i.e. as in treatments described in examples 6(b), 6 (c) , 6 (d) , 6 (e) , 6(f) and 6 (g) below.

Example 6(b)

Two kilogram samples of broken beans were dried byburying them in nylon net bags in the mass of whole beanson the hot air dryers using the standard air températureof '60 °C. The bags were inserted towards the end of the48 hour period of drying when the bulk mass of beans wasdrier than the broken beans, which therefore did notabsorb any moisture from the whole beans.

The broken beans were dry (approximately 5% nib moisture)after 4 hours and gave distinctly better flavour (lessacid/sour, acrid, bitter and astringent) than a 2 kgconed and quartered sample from the mass of beans whichoriginated from the same mixed planting materials andwith the same fermentation history but dried for 48 hourson the hot bed dryers, i.e. in comparative example 6(a)above. 14 010844

Example 6 (c)

Flavour was further improved by drying the broken beansin a current of air at ambient température for 16 hoursand then for a further period of up to 4 hours at 60 °C,as above, to 5% nib moisture. In these trials the brokenbeans were dried at about 4 cm bed depth in boxes with afine wire mesh (mosquito net) based and solid sides,inserted in bulk samples of. fermented beans being driedat about 12 to 18 inches bed depth on fiat bed dryers.This example used a "high" velocity air flow to dry thecocoa beans.

The beds were dug out so that the boxes could be insertedwith the mesh base in direct contact with the perforatedfloor of the drying platform. The heat source to thedrying bed was turned off one hour before the boxes wereinserted. If the bulk beans on the drier were still wetand/or deep, most of the air onto the drier waschannelled through the thin layer of broken beans in theboxes, that being the point of least résistance. Theflow rates of air through the broken beans were estimatedat between 15 and 30 cubic métrés per minute. Underthese conditions the broken beans dried very quickly.Draeger tube estimâtes of acetic acid concentration showed that acid low was rapid also from about 40ppm attime zéro, the acetic acid concentration had dropped tolOppm after only 4 hours before reaching a limitingconcentration of less than 5ppm after 16 hours.

There was very little différence in flavour betweenbroken beans dried at 60°C throughout under theseconditions and samples taken after 4, 8, 12 and 16 hoursambient drying under these conditions pr-ior to finaldrying at 60°C. There is obviously more to the process 15 010844 than the rapid removal of acid. If indeed the flavourimprovement results from the enzymic modification of thenibs under conditions of reducing acidity, then theenzymic reactions will need time to progress and may doso only when the nibs remain sufficiently moist. Fastdrying whole beans at high températures might hâve 3possible disadvantages - acidity is retained, the highertempérature deactivates the enzymes involved and thebeans dry too quickly.

Example 6 (d).

In this example a diesel fuelled drier with plentifulsupplies of palm kernel shells for solid fuel burners wasused. The bed was covered with jute (gunny) sacks todirect a much reduced air flow through the broken beansin boxes which occupied a tiny proportion of the totaldrying area. When the powerful fan was switched on toblow air at ambient température, the sacking covering thefloor billowed like a thin carpet on a draughty floor andthe· air flow through the broken beans was reduced to 5 to10 cubic métrés per minute.

Under these conditions the acetic acid concentration,starting again at 40 ppm was reduced to only 28ppm after5 hours and had reached the limiting concentration ofless than 5 ppm after between 20 and 24 hours. It wasnoticeable that the nibs which were still appreciablymoist were much darker in colour than those fromtreatment in example 6(c).

Cocoa liquors had much more cocoa flavour, were lessastringent and were darker in colour and more viscousthan ail previous samples from the présent trials. Therate of drying was reduced still further by increasing 16 010844 the bed depth of broken beans in the boxes to 8cm. Theflow rate was then about 3 cubic métrés per minuteinitially rising gradually to about 7 as the beans driedand offered less résistance to air flow through theboxes.

Example 6(e)

Prior to example 6(d), and while recognising thatconsiderably more flavour improvement was needed, it wasdecided to test the flavour stability of dried nibs.

Plain chocolatés were made from nibs from example 6(c).Half of the chocolatés were kept in a fridge and theother half at room température (air conditioned). Afterpréparation of the first batches of chocolaté, the nibswere divided and stored, one portion deep frozen andanother at ambient température. One week later furtherbatches of chocolaté were made from nibs from the twostorage conditions. The chocolatés were stored as beforeand were allowed to condition for at least 4 days fromthe time of préparation before tasting.

Whereas there were no appréciable différences in flavourbetween chocolatés from the same batch stored in thefridge or at room . température, there was a markeddétérioration in the flavour of chocolatés made from nibsstored for 1 week at ambient température. A rancid fatand bitter note had developed.

This began to fit in with a common but ill defined off-flavour that had been observed throughout the course ofthe work. It was described as "wheaty" and it had beenobserved when the new drying process was applied in theMARS laboratory in Kuala Lumpur. It was also described 17 010844 as "rancid fat"- or "cereal". The note was particularlypronounced in deshelled beans which had been sundried.

It had also been noticed that dried nibs developed a 5 whitish appearance during storage which at first wasfeared to be mould growth but was later recognised as fatbloom. The bloom disappeared on holding the nibs in aclenched fist for a few minutes or after placing the nibsin a warm oven. If free fat was deposited on the large 10 surface area of finely divided nibs, it was however felt to be inadvisable to blow air at 60 °C through a bed ofbroken beans for up to 4 hours in order to complété thedrying process. 15 From that observation the treatment of example 6 (f) was devised which appears to hâve given the best flavourquality from the présent sériés of trials (see example 8'and Table 3 - below). 20 Example 6(f)

Broken beans were dried by blowing air at ambienttempérature for 24 to 26 hours over the débris spreadthinly on trays. The partially dried nibs, a few werestill rubb.ery and therefore not completely dry, were 25 stored and made into liquors without any furthertreatment to fully dry the nibs. Liquors made from nibsdried at ambient température throughout hâve shown thelowest levels of "whéaty" or "rancid" flavour and mayindeed be completely free from that flavour defect. 30 Furthermore, the nibs did not develop any fat bloom while stored for three days at tropical températures inMalaysia.

Example 6(g) Recommended process 35 on the basis of the observations from the above’ examples 18 010844 6 (a) to 6(f), the following preferred process was devisedusing standard fermented beans after δ days boxfermentation.

The beans were washed for 10 minutes to remove residualmucilage and then skin-dried, keeping the externaltempérature of the skin dried beans below 45PC. The skindried beans were broken either manually or mechanicallybetween rollers. The broken beans were then spread ontrays and dried for about 24 hours in a current of air atambient température blown over but not through thedébris. After 20 hours drying the nib moisture was lessthan 7.5%. A dark purple brown colour in the dried nibswas achieved which produced a dark and viscous liquorwith distinct cocoa flavour and low astringency andacidity. Particles of dry shells that were free ofadhering nibs were removed by coarse winnowing orsieving.

Re'sults of taste trials

Examole 7 : Tests of different génotypes BAL209, PBC123, NA33 and UIT1 each with 0 and 10 dayspost harvest pod storage and prepared by (1) fast dryingwhole beans and (2) broken beans according to example6 (c) were tested. Fifty kilograms of wet beans werefermented in baskets according to BAL/BCCA flavour trialprocedure.

The results are the averages of 2 tests of each liquorfrom a first set in which the four génotypes with thesame drying treatment were tested and from a second setof 4 comprising a single génotype with the 2 pod storage 19 010844 I I ! ’·'ΛΤ·>'·. · <ht’ i_ x. ti ci u u ici x u o

/4 v“«t r *î vi /“T \u.x. y xny 4- V-»U-iAt

η f· t z-irt e«'wVAA'-AX ko JL samples of whole beans of ail four génotypes areavailable.

Results in Tables 2 and 3 show that slow drying of brokenbeans has consistently improved the flavour and is moreeffective in increasing cocoa flavour and reducingastringency than the post harvest pod storage treatment.Improvements were particularly pronounced when the newdrying procedure was applied to BAL209 and UIT1 bothwithout pod storage. This suggests that the dryingtreatment is affecting the polyphenol composition.

When polyphenol concentration and astringency are high,as in BAL209 and UIT1, a great proportion of the criticalmaterial is altered and the effect is then more dramatic.In addition to increasing cocoa flavour intensity andreducing astringency, the new drying process tends toretain the characteristic secondary flavours of thegénotypes, e.g. the brown fruit/floral notes of PBC123and NA33 and the bitterness of UIT1. 20

TABLE 2

Table 2. Effects of drying treatments applied to génotypeswith 0 and 10 days pod storage. F t avour characteristic BAL209 NA33 O-HA O-NP 10-HA 10-NP O-HA O-NP 10-HA 10-NP Cocoa flavour intensity 1.9 5.9 4.7 6.4 5.1 7 6.1 7.7 Acid/sharp 3.6 1.3 2.6 1.4 2.6 1.4 2.2 1 Astringent 5.9 . 1.6 3.9 1.6 2.5 1.4 2.1 1.4 Bitter 4.9 1.1 3.1 1.3 2.3 1.1 2.1 0.9 Fragrant floral 0 0 3.1 1.4 0 0 1.4 1.2 Brown fruit 0 0 09 0 1 2.7 2.9 2.1 Viscous/thick mouthfeel 5.3 7 6.2 7.2 6.6 8 6.9 8 PBC123 UIT1 Cocoa flavour intensity 6 6.9 6.3 7.5 2.3 4.7 2.2 4.5 Acid/sharp 2.2 1.1 2.6 0.9 2.9 1.5 2.5 1.1 Astringent 2.1 1 2.5 1 5.2 2.5 4.9 2.4 Bitter 1.6 1.2 2.2 0.9 4.6 . 2.1 4 1.8 Fragrant floral 0 0 0 0 0 0 0 0 Brown fruit 2.8 1.9 2.6 1.8 0.5 0 0 0 Viscous/thick mouthfeel 7.1 7.6 7 7.8 5.2 6.6 5.3 6.4

Key to table : Génotypes, BAL20'9, NA33, PBC123 and UIT1. O-HA = 0 Days pod storage and hot air dried. 10-NP = 10 Days pod storage and new drying process [example 6 (c) ] . 10-HA = 10 Days pod storage and hot air dried. 10-NP = 10 Days pod storage and new drying process [.example 6 (c) ] . 21 010844

Characteristics- were scored for intensity on 10cm. openline scales. Higher scores dénoté stronger intensifies.Scores are the averages of 2 blind tests of each liquor.Différences greater than 1.0 are significant. TABLE 3

Table 3. Effects of pod storage and drying treatments on flavour characteristics averagedover ail four génotypes. N « 16 for each treatment. Cocoa flavourintensity Acid/sharp Astringent Viscous/thick mouthfeel 0 Days pod storage 5 2.1 2.8 6.7 10 Days pod storage 5.7 1.8 2.5 6.9 Hot air drying 4.3 2.7 3.6 6.2 New drying process6(0 6.3 1.2 1.6 7.3

The new drying process is more effective than pod storagein bringing about the desired changes in these fourcritical flavour characteristics.

Example .8: Beans from mixed planting materials - BAL standard process versus new process

Twenty five kg samples were taken on eight successivedays just before the fermented beans were due to go on tothe hot bed dryers. 2 kg cohed and.quartered samples innet bags were dried together with 2.5 tonne lots offermented beans from which the 25 kg samples had beentaken. The remainder of the 25 kg sample was washed,skin dried and broken manually. The broken beans weredried according to the above drying treatments in example6(c) (4 samples), example 6 (d) (3 samples) and example6(f) (1 sample). SUBST1TUTE SHEET (RULE 26) 22 010844

The results in' Table 4 show that the new drying processimproved the flavour on ail eight occasions. The dryingtreatment of example 6(d) was better than the treatmentof example 6 (c) and the best overall treatment wasexample 6{f) in terms of increased cocoa flavour andreduced astringency combined with a lower score for"wheaty/rancid" flavour than in any of the other dryingtreatments of broken beans from the examples. TABLE 4

Table 4. Effects of drying treatments Air at 60° * T reatment 6(0# T reatment 6(d)# Treatment 6(f)# Target flavour $ Cocoa flavour intensity 1.7 4.6 6.1 6.6 7.1 Acid/sharp 5.4 2.5 1.5 1.5 1.3 Astringent 5.2 3.5 1.9 1.7 1.7 Bitter 4.4 2.8 1.6 1.1 1.1 Fragrant/floral 0 0 0.6 0.6 1.3 Viscous/thick mouthfeel 4.9 6.4 6.8 7 7.6 Wheaty/rancid Absent Présent Présent Wk/Absent Wk/absent Number of samples 8 4 3 1 1 Total number of tastings 10 > 7 9 2 3

Key to table: * - BAL standard beans, whole hot air dried. 8

Samples tested. 6 (c) # = Drying treatment in example 6(c). Broken beansdried in current of air for 16 hours then for4 hours at 60°C. 23 010844 6(d)# = 6(f># = 5 $ =

Drying treatment in example 6 (d). Brokenbeans. Slower ambient air drying for 20-24hours followed by hot air drying for 4 hours,Drying treatment in example 6 (e). Brokenbeans. Slower ambient air drying for 24-26hours. No further treatment.

Target flavour from earlier experiments(resuits not shown).