Influence de différents traitements technologiques sur la fermentation du cacao et sur la qualité du chocolat au Cameroun
Cocoa was prepared in the Cameroon, taking into account the following different methods of treatment: 1. Duration of fermentation. 2. Frequency of stirring. 3. Washing of fresh beans. 4. Quantity of pod husk and placenta in the mass being fermented. 5. Combined action of the two previous treatments. Temperatures were taken at regular intervals during fermentation. Samples of saleable beans were examined for their different physical and chemical characteristics: 1. Cut-test. 2. Percentage weight of the component parts of the beans. 3. Amount of oxidizable matter by means of the KMnO4 test. 4. Weight by the litre, average weight of bean, and bean size. 5. Amount of ammoniated nitrogen (Conway's micro-diffusion). Organoleptic tests were carried out on the chocolate. Fermentation for 7 days was the best for obtaining good quality cocoa. With a shorter period, the physico-chemical and organoleptic data indicated a fall in quality. Fermentation for eight days gave good quality cocoa, but the danger of developing moulds increased as well as loss in dry weight. The frequency of stirring was an important factor responsible for the final quality. It affected the amount of ammoniated nitrogen, the bitterness, sharp taste and acidity. The most advantageous method of stirring consisted of turning the beans after 24, 48, 96 and 144 hours of fermentation and removing from the fermentary after 168 hours. The washing of fresh beans, as we did, did not affect the fermentation process, but caused a reduction in the output. The litre weight of saleable beans was reduced for the washed beans. The cut-test shows little difference but not in favour of the washed beans. The amount of oxidizable material found by means of the KMnO4 test was less for these beans, which was a sign of more prolonged fermentation (degradation of the polyphenols). On the other hand, an average rate of 4 percent beans were observed to be growing (false germination). The presence of fragments of pod husks and placenta did not in any way harm the fermentation, and up to 10 per cent content, it even accelerated the process. On the other hand, there was a decline in out-put: the weight per litre was lower, and the average bean weight was less. The fermentation seemed to be accelerated, especially with the presence of 10 per cent pod fragments. The recorded effects of these two treatments increased with the duration of fermentation, and affected the physical and chemical qualities of the saleable beans. As regards the organoleptic tests, bitterness and aroma were not affected by washing and fermentation in the presence of pod debris. On the other hand, sharp taste and acidity were considerably reduced by washing. The most important factors which have a bearing on the final quality of the cocoa are: fermentation, frequency of stirring, and washing of beans before fermentation
| Main Authors: | , , |
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| Format: | biblioteca |
| Published: |
Tafo (Ghana)
1971
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| Subjects: | CACAO, FERMENTACION, CHOCOLATE, PROPIEDADES ORGANOLEPTICAS, PROPIEDADES FISICO-QUIMICAS, AROMA, ACIDEZ, CAMERUN, |
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| Summary: | Cocoa was prepared in the Cameroon, taking into account the following different methods of treatment: 1. Duration of fermentation. 2. Frequency of stirring. 3. Washing of fresh beans. 4. Quantity of pod husk and placenta in the mass being fermented. 5. Combined action of the two previous treatments. Temperatures were taken at regular intervals during fermentation. Samples of saleable beans were examined for their different physical and chemical characteristics: 1. Cut-test. 2. Percentage weight of the component parts of the beans. 3. Amount of oxidizable matter by means of the KMnO4 test. 4. Weight by the litre, average weight of bean, and bean size. 5. Amount of ammoniated nitrogen (Conway's micro-diffusion). Organoleptic tests were carried out on the chocolate. Fermentation for 7 days was the best for obtaining good quality cocoa. With a shorter period, the physico-chemical and organoleptic data indicated a fall in quality. Fermentation for eight days gave good quality cocoa, but the danger of developing moulds increased as well as loss in dry weight. The frequency of stirring was an important factor responsible for the final quality. It affected the amount of ammoniated nitrogen, the bitterness, sharp taste and acidity. The most advantageous method of stirring consisted of turning the beans after 24, 48, 96 and 144 hours of fermentation and removing from the fermentary after 168 hours. The washing of fresh beans, as we did, did not affect the fermentation process, but caused a reduction in the output. The litre weight of saleable beans was reduced for the washed beans. The cut-test shows little difference but not in favour of the washed beans. The amount of oxidizable material found by means of the KMnO4 test was less for these beans, which was a sign of more prolonged fermentation (degradation of the polyphenols). On the other hand, an average rate of 4 percent beans were observed to be growing (false germination). The presence of fragments of pod husks and placenta did not in any way harm the fermentation, and up to 10 per cent content, it even accelerated the process. On the other hand, there was a decline in out-put: the weight per litre was lower, and the average bean weight was less. The fermentation seemed to be accelerated, especially with the presence of 10 per cent pod fragments. The recorded effects of these two treatments increased with the duration of fermentation, and affected the physical and chemical qualities of the saleable beans. As regards the organoleptic tests, bitterness and aroma were not affected by washing and fermentation in the presence of pod debris. On the other hand, sharp taste and acidity were considerably reduced by washing. The most important factors which have a bearing on the final quality of the cocoa are: fermentation, frequency of stirring, and washing of beans before fermentation |
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