USE OF A SOAKING PROCEDURE TO IMPROVE DRY BEAN ATTRIBUTES - MILESTONE 7 pdf

013/VIE05: FERMENTATION AND DRYING TRIAL AT NLU September, 2007 ATTACHMENT TO MILESTONE REPORT TRIAL TITLE: “USE OF A SOAKING PROCEDURE TO IMPROVE DRY BEAN ATTRIBUTES” Introduction: It is generally understood that the length of fermentation has an effect on the quality attributes of cocoa Attributes affected include shell content, pH, titrable acidity (TA), cut test results and flavour attributes It has also been demonstrated that soaking of beans in water, after fermentation, leads to dried cocoa with higher brown bean percentages, lower shell content and improved flavour characteristics, (Hollywood, N W 1997) This trial was undertaken to demonstrate whether the effects of fermentation time and soaking were applicable to Vietnamese cocoa Materials and Methods: The factors mentioned in the introduction led to the conduct of a fermentation where sub-samples were taken for drying on days five, six and seven of the fermentation These sub-samples were then divided into two with one half being soaked in water for two hours before placement on the dryer The other half was placed directly on the dryer This lead to dried bean samples being generated as follows: Five days fermented un-soaked Five days fermented plus soaked Six days fermented un-soaked Six days fermented plus soaked Seven days fermented un-soaked Seven days fermented plus soaked Pods were a mixture of clones and hybrids from Dak Lak and stored for eight days prior to breaking Beans were also spread, in an indoor area for four hours, prior to being placed in the fermentation box This spreading procedure led to an 11.98% moisture loss After spreading, 95.5kg of wet beans were left and these were fermented in a wooden box at 45cm bean depth, for seven days Sub-samples were taken on days 5, and These beans were then treated as listed above and dried on a solar dryer at Nong Lam University Beans were turned, in the boxes, on days two and four Temperatures of the fermentations were taken from the top, middle and bottom of the fermenting boxes on a daily basis On each day of the fermentation, samples of fermenting beans were taken for measurements of pH and titrable acidity of the cotyledon and pulp/testa Dry beans were subjected to the tests of pH, titrable acidity, shell content, moisture, cut test and sensory evaluation All tests were conducted as per the CARD Cocoa Analysis Manual Results and Discussion: The temperature of the fermentation, on various days, is presented in figure Temperatures encountered were fairly typical with a decline in temperatures from day three onwards indicating that the fermentation may only need to have been conducted for four or five days Temperaures of Fermentation 50 Temperature oC 45 40 Fermenting beans 35 30 25 Day of Fermentation Figure 1: Temperatures of fermentation during the seven days of fermentation Figure one demonstrates temperature rises typical of a cocoa fermentation The decline in temperature from day five onwards indicates that a fermentation time of six days would probably be sufficient pH Bean components 6.5 pH Bean components 5.5 Cotyledon Pulp 4.5 3.5 3 Day of Fermentation Figure 2: pH of bean components during fermentation for treatment WS1 Typically, during a cocoa fermentation, pH values of the different components equilibrate by the end due to a diffusion of organic acids through the cotyledon from the pulp/testa The rise in pH of the pulp is slower than usual otherwise trends demonstrated in this fermentation could be considered as fairly typical of a cocoa fermentation DRIED BEAN ANALYSIS During the fermentation trial, samples were taken from the fermenting box on days 4, and and then divided for soaking and un-soaked In this way, an effect of fermentation time, as well as soaking could be noted The effect of the different treatments on the pH of the resultant dried cocoa is presented in figure three pH Dried Bean components 5.1 pH un-soaked nib 4.9 soaked nib 4.8 4.7 Day of Fermentation Figure 3: pH of dried bean components taken on days 5, & of the fermentation Figure three demonstrates a higher pH of the nib, due to soaking, on each day of the fermentation sampled pH values tended to decrease with length of fermentation time West African cocoa usually has a pH of around 5.1 The results indicate that a fermentation period of five days, with the soaking procedure, could be suitable for producing a West African type cocoa Titrable Acidity (mls 0.1N NaOH/g cocoa Titrable Acidity Dried Bean components 5.4 5.2 Un-soaked Nib 4.8 Soaked nib 4.6 4.4 4.2 Day of Fermentation Figure 4: Titrable acidity of dried bean components taken on days 5, & 7, of the fermentation Figure four demonstrates the lower levels of organic acids in nibs from beans which have been soaked and an increase in acidity with length of fermentation time As with pH data, these results indicate that a five day fermentation period, with the soak procedure, could produce a West African type cocoa Percent Brown Beans in Cut Test 80 % Brown Beans 70 60 50 un-soaked Soaked 40 30 20 10 Day of Fermentation Figure 5: Fully brown bean percentage in cut test results for each treatment Figure five demonstrates a dramatic effect of soaking on the fully brown bean percentage Under the current buyer preference for high brown bean counts, this treatment could be strongly recommended as long as flavour attributes are not adversely affected Percent Purple/Brown Beans in Cut Test 80 % Pertly Brown Beans 70 60 50 Un-soaked 40 Soaked 30 20 10 Day of Fermentation Figure 6: Partly brown bean percentage in cut test results for each treatment Figure demonstrates an almost inverse relationship between fully brown beans and partly brown This indicates that a high proportion of beans which would be partly-brown without soaking, become brown with soaking Purple beans (2%) occurred only on day of the un-soaked beans and this is not presented graphically Shell content of dried beans Percentage shell Content 16 15.5 15 % Shell 14.5 Soaked 14 unsoaked 13.5 13 12.5 12 Day of Ferm entation Figure 8: The effect of soaking fermented beans, prior to drying, on shell content Figure demonstrates that the shell content of beans which have been soaked in water, prior to drying is less than that of beans which haven’t been soaked Again this is desirable from the industry stand point as shell is a waste product Summary Results presented indicated that the desirable attributes of less acidity, higher brown bean percentages and less shell were obtained by using the soaking procedure Sensory analysis of samples was not conducted There is a need to confirm whether the soaking procedure produces cocoa closer to the West African standard References: N Hollywood “The effect of fermentation time and washing of cocoa prior to drying on cocoa quality in Papua New Guinea” Cocoa Growers Bulletin, 1997 FERMENTATION AND DRYING TRIAL CARD 05VIE013 NLU DECEMBER, 2007 ATTACHMENT TO MILESTONE REPORT TRIAL TITLE: Comparison of fermentations conducted using stored and un-stored pods, bean spreading prior to fermentation, bean washing post fermentation and box and heap fermentations Introduction: Fermentation trials conducted at WASI in April 2007 had indicated that spreading of beans prior to fermentation led to more rapid temperature increases and higher brown bean percentages in cut test results A previous trial, conducted at WASI, had indicated that more rapid temperature increases, during fermentation, and higher brown bean counts resulted from storage of pods, for one week, prior to fermentation The practice of soaking beans in water, at the end of fermentation and prior to drying was also conducted at Can Tho University in April 2007 and Nong Lam University in September 2007 These trials had demonstrated higher brown bean counts and less acidity and shell content were obtained by soaking beans prior to drying Sensory testing was conducted on the dried bean samples from WASI at Nong Lam University (NLU) in December 2007 and the results were inconclusive as to whether the practices of bean spreading, pod storage and fermentation in a hot house led to improved cocoa flavour As regards pod storage and bean spreading, trials conducted in Malaysia have indicated improved flavour resulting from both practices (Biel, 1987) In Vietnam, cocoa buyers generally pay a premium for beans with the highest brown bean counts Therefore the practices of pod storage and bean spreading were tested again at NLU in December 2007 Heap fermentations and box fermentations were also conducted to note any differences between the two fermentation methods The practice of soaking of beans in water for two hours prior to drying was applied to each fermentation treatment as this also leads to higher brown bean counts (Hollywood, 1997) Materials and Methods: Pods were obtained from the WASI plantation, as insufficient pods were available at NLU, and transported by truck to NLU The following fermentation treatments were conducted: Treatment 1: Box fermentation of 100kg of beans from fresh pods Treatment 2: Box fermentation of 100kg of beans from pods stored for days Treatment 3: Box fermentation of 100kg of beans from pods stored for days and spread in sun for hours prior to placement inboxes Treatment 4: Heap fermentation of 100kg of beans from pods stored for days Treatment 5: Heap fermentation of 100kg of beans from fresh pods All treatments had sub-samples taken for drying on days 4, and These sub-samples were each divided in two with one half being soaked for hours in water (S) and the other un-soaked (U) This led to the following list of dried bean samples: Table 1: List of dried bean samples generated during fermentation trial Dried bean sample Fermentation and drying treatment T1D U T1 D W T1 D 5U T1 D W T1D U T1 D W T2D U T2 D W T2 D 5U T2 D W T2D U Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking T2 D W T3D U T3 D W T3 D 5U T3 D W T3D U T3 D W T4D U T4 D W T4 D 5U T4 D W T4D U T4 D W T5D U T5 D W T5 D 5U T5 D W T5D U T5 D W Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Fermentation treatment dried day without soaking Fermentation treatment dried day with soaking Beans were fermented for six days, with one turn on the second day and with sub-samples being taken, from each treatment, on days 4, and These beans were placed in a solar dryer and were then subjected to physical and chemical testing using standard methods Temperatures of the fermentations were taken from five positions in the top, middle and bottom layers of the fermenting boxes at 8AM, 12 noon and 4PM each day of the fermentation The five temperature measurements for each layer were then averaged for each fermentation treatment The temperature values presented are the averages of those encountered at noon Samples of fermenting beans were taken for measurements of pH, titrable acidity and moisture of whole beans, cotyledon and pulp/testa on days 4, & of the fermentation Weights of 50 beans and the bean components of cotyledon and pulp/testa were also conducted Dry beans were subjected to the tests of pH, titrable acidity, moisture, shell content and cut test Results and Discussion: Temperaures of Fermentations 50 Temperature oC 45 T1 T2 40 T3 T4 35 T5 Ambient 30 25 Day of Fermentation Figure 1: Temperatures of fermentations during the six day fermentation period The fermentation temperatures encountered are unusual in that there is not an accelerated fermentation occurring due to pod storage or spreading of the beans in the sun prior to fermentation This is in distinction to results obtained at WASI and to other trials conducted in Vietnam or reported from countries such as Malaysia and Indonesia All treatments, including both box and heap fermentation methods followed a very similar pattern and reasons for this are not immediately apparent Moisture % Whole Beans 65 60 % Moisture 55 T1 T2 50 T3 T4 T5 45 40 35 Day of Fermentation Figure 2: Moisture content of whole beans during the six days of fermentation As would be expected, the highest initial moisture contents occurred in the fresh beans of treatments one and five Pod storage led to lower initial moisture contents in treatments two and four The lowest moisture content occurred in the beans which had been subjected to pod storage and bean spreading (treatment 3) However as the fermentation progressed, differences in moisture content were not consistent The treatments which generally had the lowest moisture content were two and three but this was not reflected in temperature profiles which could be expected to be higher in these treatments All treatments had decreasing moisture levels as the fermentations progressed This would be due to drainage from the boxes and heaps together with evaporation Weight 50 Whole Beans (g) 135 130 125 120 Weight (g) T1 115 T2 110 T3 105 T4 T5 100 95 90 85 Day of Fermentation Figure 3: Weight of 50 whole beans during the six day fermentation Differences in initial bean weights would be mainly affected by the practices of pod storage, during which moisture loss occurs and bean spreading, where moisture drains off On day one, the weight of whole beans was as could be expected, with fresh beans of treatments one and five having the highest weights, treatments two and four being intermediate and treatment three having the lowest weight However, as the fermentation progresses the distinction is not so clear and bean weights not necessarily correspond with moisture levels This may be due to inherent variability in bean sizes Weight 50 Cotyledons (g) 90 85 Weight (g) 80 T1 75 T2 70 T3 T4 65 T5 60 55 50 Day of Fermentation Figure 4: Weight of 50 cotyledons during the six day fermentation Differences in whole bean weights were not reflected in kernel weights This is probably due to the fact that most of the differences in whole bean weights are due to loss of moisture from the pulp There is a general tendency for cotyledon weights to increase with length of fermentation time This may be due to an uptake of moisture from the pulp to the cotyledons Weight 50 pulp/testa (g) 60 55 Weight (g) 50 T1 45 T2 40 T3 T4 35 T5 30 25 20 Day of Fermentation Figure 5: Weight of 50 pulp/testa during the six day fermentation As with whole bean weights, pulp weights on day one, reflect the treatments given to beans Beans from fresh pods (T1 & T5) have the highest pulp weights Beans from stored pods (T2 & T5) have lower pulp weights due to evaporation during storage and beans subject to pod storage and spreading (T3) have the lowest weights As the fermentation progresses, there is a general downward trend This would be due to drainage during fermentation Treatments four and five show the lowest pulp weights by the end of the fermentation and this may be due to greater drainage of moisture from the beans than that in the box fermentations Kernel/Pulp Ratio 2.5 2.3 2.1 1.9 C/P Ratio T1 1.7 T2 1.5 T3 1.3 T4 T5 1.1 0.9 0.7 0.5 Day of Fermentation Figure 6: Kernel to pulp ratio during the six day fermentation In an inverse relationship with pulp weights, kernel to pulp ratios are the lowest for fresh pods (T1 & T5), intermediate for stored pods (T2 & T4) and lowest for stored pods and spread beans (T3) Similarly, by day six, the heap fermentations (T4 & T5) have the highest kernel/pulp ratios pH Bean Components T1 pH Bean Component 6.5 Whole Bean 5.5 Kernel Pulp 4.5 3.5 Day of Fermentation Figure 7: pH of bean components during fermentation for treatment one pH Bean Components T2 6.5 Whole Bean pH 5.5 Kernel Pulp/testa 4.5 3.5 Day of Fermentation Figure 8: pH of bean components during fermentation for treatment two Figures seven and eight demonstrate higher ph values of whole beans from the stored pods on day one Conversely pH values of the kernels of stored pods are lower on day one Pod storage also resulted in higher pH values for the pulp on day one On day six of the fermentation stored pods (T2) had whole bean and cotyledon ph values slightly higher than those of fresh pods (T1) This is usually the case with pod storage causing less acidic beans pH Bean Components T3 6.5 Whole Bean pH 5.5 Kernel Pulp/testa 4.5 3.5 Day of Fermentation Figure 9: pH of bean components during fermentation for treatment three In treatment three, where pods had been stored and then the beans spread, kernel pH on day one was markedly elevated and pulp pH slightly lower than treatment two Whole bean pH on day one was more elevated than occurring from pod storage alone (T2) At the end of the fermentation, the pH of bean components, at around 4.8, was lower than that for treatments one and two pH Bean Components T4 6.5 Whole Bean pH 5.5 Kernel Pulp/testa 4.5 3.5 Day of Fermentation Figure 10: pH of bean components during fermentation treatment four pH Bean Components T5 6.5 Whole bean pH 5.5 Kernel Pulp/Testa 4.5 3.5 Day of Fermentation Figure 11: pH of bean components during fermentation treatment five Figure 10 demonstrates that in the heap fermentation, the stored pods of T4 showed a similar trend in whole bean, kernel and pulp pH values between days one and two as occurred in the stored pods of the box fermentation (T2) Day one pH values, for fresh pods in figure 11, show similar levels as in the box fermentation of fresh pods At the end of fermentation, pH values of bean components of the stored pods in T2 and T4 showed similar trends with a rise in pH occurring between days & to a final pH value around 5.0 In the heap fermentation of the fresh pods (T5), on the other hand, a steep decline in pH levels occurred between days & The final pH value of around 4.40 was the lowest of all treatments TA Bean Components T1 Titrable acidity 2.5 Whole Bean 1.5 Kernel Pulp/testa 0.5 Day of Fermentation Figure 12: Titrable acidity of bean components, during fermentation of treatment one TA bean components T2 Titrable Acidity (mls 0.1N NaOH/g) 2.5 Whole bean 1.5 Kernel Pulp/testa 0.5 Day of Fermentation Figure 13: Titrable acidity of bean components, during fermentation of treatment The titrable acidity values presented for fresh and stored pods in figures 12 and 13 did not always reflect the trend in ph values presented in figures & On day one, kernels of stored pods had a lower pH than kernels of fresh pods and this is reflected in higher titrable acidity levels in the stored pod kernels However, with whole beans on day one, stored pods had higher pH and higher titrable acidity levels than fresh pods Also pulp pH and titrable acidity levels, for stored pods were both higher than those for fresh pods This is possibly due to a difference in organic acid composition and other factors caused by pod storage On most other days, titrable acidity levels tended to be inversely related to pH in both treatments As indicated by pH values, stored pods had lower levels of titrable acidity by day six of the fermentation TA bean components T3 Titrable Acidity (mls 0.1N NaOH/g) 2.5 Whole bean 1.5 Kernel Pulp/testa 0.5 Day of Fermentation Figure 14: Titrable acidity of bean components, during fermentation, for treatment In treatment three, where beans were spread after pod storage and breaking, titrable acidity levels tended to be more consistently inversely related to pH than in treatments one and two Treatment three had the lowest pH values on day six of fermentation and this was reflected in it having the highest titrable acidity levels of the box fermentations on this day TA bean components T4 Titrable Acidity (mls 0.1N NaOH/g) 2.5 Whole bean 1.5 Kernel Pulp/testa 0.5 Day of Fermentation Figure 15: Titrable acidity of bean components, during fermentation of treatment (heap fermentation stored pods) 10 TA Bean Components T5 Titrable acidity 2.5 Whole bean 1.5 Kernel Pulp/testa 0.5 Day of Fermentation Figure 16: Titrable acidity of bean components, during fermentation of treatment (Heap fermentation, fresh pods) In the heap fermentations of treatment (stored pods) and treatment five (fresh pods) some large differences occurred to the pH and titrable acidity levels to that in corresponding box fermentations treatments In treatment five, titrable acidity levels were generally inversely related to pH values However with the pulp, pH and titrable acidity tended to increase together between days and Between days & pH levels fell sharply and this was reflected in a sharp increase in titrable acidity measurements This treatment had the lowest pH and highest titrable acidity levels of all treatments at the end of six days fermentation Therefore, in this case, the heap fermentation of fresh pods (T5) resulted in more acidic cocoa than the box fermentation (T1) In treatment four (stored pods), the pH of all bean components were higher than in treatment five (fresh pods) on day one pH values of kernel and whole beans increased on day and this was reflected in a decrease in titrable acidity From day two to day five pH values of kernel and whole beans declined sharply and this was reflected in titrable acidity levels rising As with pulp between days and in treatment five, pH and titrable acidity values of pulp had an apparent anomaly of both rising from day to in this treatment This may be associated with a change in organic acid composition e.g declining levels of citric acid being replaced by acetic and lactic acids From day five to six, there was a sharp rise in pH values and this was reflected in a sharp decline in titrable acidity On day six, at the end of the fermentation pH and titrable acidity levels were similar for treatments two and four i.e box and heap fermentations of stored pods 11 DRIED BEAN ANALYSIS During the fermentation trial, sub-samples were taken from the fermenting boxes on days 4, and Half of each sub-sample was soaked in water for two hours before placing on the drier and the other half placed on the drier immediately In this way, an effect of both fermentation time and washing cocoa could also be noted The effect of the different treatments on the pH, titrable acidity and shell content of the resultant dried cocoa is presented in tables 1, & respectively pH and titrable acidity of dried cocoa pH Dried Beans 5.8 5.6 T1U 5.4 pH T1W T2U 5.2 T2W T3U T3W 4.8 4.6 Day of Fermentation Figure 17: pH of dried beans from the box fermentation treatments Figure 17 demonstrates an increase in pH values with length of fermentation time for all box fermentation treatments It also demonstrates higher pH values for washed beans for each day of all fermentation treatments It can also be noted that the lower the pH of un-washed cocoa is, the greater the elevation of pH caused by washing With un-washed cocoa, it was surprising to note that the highest pH cocoa obtained was from fresh pods (T1U) Stored pods (T2U) had the lowest pH values and stored plus bean spreading (T3U) had intermediate values This is in contradiction to the previous trial conducted at WASI and what is frequently reported in other countries The reason for this is not immediately apparent After washing, the pH values of all treatments were fairly similar 12 Titrable acidity Dried Beans 2.5 2.3 TA (mls 0.1N NaOH/g) 2.1 1.9 T1U 1.7 T1W T2U 1.5 T2W 1.3 T3U 1.1 T3W 0.9 0.7 0.5 Day of Fermentation Figure 18: Titrable acidity of dried beans from the box fermentation treatments In figure 18, titrable acidity levels tend to be inversely related to pH values in every case on days & However on day six there is an anomaly of the stored and spread beans (T3) having higher titrable acidity on day six even though its pH value is higher on day than In the fermentation of treatment 3, titrable acidity did increase sharply between days & but this does still not explain a lack of inverse correlation between pH and TA in the dried bean sample pH Dried Beans 5.8 5.6 5.4 pH T4U T4W 5.2 T5U T5W 4.8 4.6 Day of Fermentation Figure 19: pH of dried beans from the heap fermentations of stored (T4) and fresh pods (T5) In the heap fermentations pH of un-washed dried beans increased between days & for the stored pods (T4) but declined for fresh pods (T5) This seems to relate to the pH of whole beans during the fermentations In T4 13 (stored pods) whole bean pH increased from 4.71 to 5.14 between days & In T5 (fresh pods) pH decreased from 5.3 to 4.6 between days & This decrease in pH in treatment appears to have been negated by the wash procedure In every case, apart from T5 Day 5, soaking of beans in water resulted in increases in pH values of dried bean samples Usually high pH cocoa has a higher chocolate flavour level This indicates that the soaking treatment could be a useful methodology in producing a West African type cocoa TA Dried Beans Titrable acidity (mls 0.1N NaOH/g) 2.5 2.3 2.1 1.9 T4U 1.7 T4W 1.5 T5U 1.3 T5W 1.1 0.9 0.7 0.5 Day of Fermentation Figure 20: Titrable acidity of dried beans from the heap fermentations of stored (T4) and fresh (T5) pods For treatment four, pH values were reflected in an inverse relationship with titrable acidity levels However in treatment five a large decrease in pH between day five and six is not accompanied by corresponding increase in titrable acidity levels The reason for this is not immediately apparent 14 Shell content of dried cocoa Shell % Dried Beans 18 17 16 T1U % Shell 15 T1W T2U 14 T2W T3U 13 T3W 12 11 10 Day of Fermentation Figure 23: Shell content of dried beans from the box fermentation treatments Shell % Dried Beans 18 17 16 % shell 15 T4U T4W 14 T5U T5W 13 12 11 10 Day of Fermentation Figure 24: Shell content of dried beans from the heap fermentations of stored (T4) and fresh (T5) pods In most cases, shell content increased with length of fermentation time This is due to an accumulation of polyphenolic breakdown products, in the pulp, during fermentation and drying In the box fermentations, both practices of pod storage and bean spreading resulted in lower shell content No effect of pod storage was noted in the heap fermentations In all cases soaking of beans resulted in a decrease in shell content, due to removal of some of the pulp during the soaking process For six day fermented cocoa, the two lowest shell contents 15 obtained were for washed beans from pods subjected to storage and from pod storage and bean spreading This would result in a more desirable product for buyers as shell is a waste product Cut test results for dried cocoa Percentage fully brown beans in cut test 100 90 % Brown beans 80 T1U 70 T1W T2U 60 T2W T3U 50 T3W 40 30 20 Day of Fermentation Figure 25: Percent brown beans in cut test of dried beans from the box fermentation treatments Percentage brown beans in cut test 100 90 % Brown beans 80 70 T4U T4W 60 T5U T5W 50 40 30 20 Day of Fermentation Figure 24: Percentage brown beans in dried beans from the heap fermentations of stored (T4) and fresh (T5) pods 16 Brown bean percentages shown in figures 21 and 22 indicate that the practices of spreading the beans, prior to fermentation and soaking of beans prior to drying, result in higher levels of fully brown beans in the cut test Also, an increase in brown bean counts, with length of fermentation time, occurs In this trial, pod storage did not result in higher brown bean counts This is in distinction to results produced in previous trials at WASI and NLU and to results from trials conducted in other countries (Biel 1987) Fermentation in heaps as opposed to boxes did not influence brown bean counts The highest brown bean counts were obtained in six day fermented beans, subject to pod storage and bean spreading, prior to fermentation Conclusions: Results obtained indicate that the practices of pod storage and bean spreading, in conjunction with washing of cocoa prior to drying, result in cocoa of several more desirable attributes These attributes include lower shell content, less acidity and higher brown bean counts With cocoa subjected to these three processing steps, four or five day fermented cocoa is preferable to six day fermented cocoa, as far as shell content and pH levels are concerned With six day fermented cocoa, shell content is higher and pH values are above the desirable range of 5.0-5.2 usually encountered in West African cocoa However on the basis of brown bean percentages, which is the main criterion applied by buyers when determining price, six day fermented cocoa has the highest level of this bean type Cocoa currently being produced in Vietnam is usually processed applying pod storage of about a week and six day or longer fermentation periods In Dak Lak province, premiums are paid for cocoa with an 80-90% brown bean count and to achieve this, farmers ferment up to nine days In the Mekong delta region, six day fermentations, in conjunction with pod storage, are usually applied and this results in brown bean percentages acceptable to buyers In comparable countries such as Malaysia or Indonesia, seven days pod storage and six day fermentation periods are also generally recommended The two additional practices applied in this trial i.e bean spreading prior to fermenting and then washing of cocoa prior to drying are fairly simple procedures which a farmer could easily conduct Neither of these procedures is generally applied in any cocoa producing country As far as flavour is concerned, the practice of washing of cocoa has been demonstrated to result in cocoa with higher chocolate flavour, lower acidity and astringency and reduced “off” flavours in trials conducted in Papua New Guinea (Hollywood, 1997) There is therefore a need to repeat this trial on a larger scale and with commercial buyers and chocolate manufacturers to finalise the flavour and processing aspects of cocoa produced with the four variables i.e length of fermentation time, pod storage, pod storage plus spreading of beans and washing of cocoa prior to drying As such a co-operative trial would require time and resources out side the scope of this project, recommendations will be made on the basis of results to date In the cocoa processing manual, the practices of one week pod storage, spreading of beans and washing of beans post fermentation will be recommended A fermentation period of six days will be recommended solely on the basis of higher brown bean percentages for which buyers currently pay a premium References: Dr Boel Biel and Bernd Meyer “The influence of pod ripening, pod storage and bean spreading on the pulp constitution and fermentation of cocoa” Malaysian Agricultural Research and Development Institute (MARDI) report, November 1987 pp 37-47 N Hollywood “The effect of fermentation time and washing of cocoa prior to drying on cocoa quality in Papua New Guinea” Cocoa Growers Bulletin, 1997 17 ... in treatment appears to have been negated by the wash procedure In every case, apart from T5 Day 5, soaking of beans in water resulted in increases in pH values of dried bean samples Usually high... 4: Heap fermentation of 100kg of beans from pods stored for days Treatment 5: Heap fermentation of 100kg of beans from fresh pods All treatments had sub-samples taken for drying on days 4, and... fermentation in a hot house led to improved cocoa flavour As regards pod storage and bean spreading, trials conducted in Malaysia have indicated improved flavour resulting from both practices